Q 1. What does an anomaly mean?
Ans. It means deviation from normal or something which has grown in an abnormal way.
Q 1a. Name the different types of developmental anomalies.
Ans. Table 1.1 shows different types of developmental anomalies:
Congenital anomalies: The defects, which are present at birth or before birth during the intra-uterine life, are known as congenital anomalies.
Hereditary developmental anomalies: When certain defects are inherited by the offspring from either of the parents, it is called hereditary anomaly. Such types of anomalies are always transmitted through genes.
Acquired anomalies: Acquired anomalies develop during intrauterine life due to some pathological environmental conditions. They are not transmitted through genes.
Hamartomatous anomalies: A hamartoma can be defined as an excessive, focal overgrowth of mature, normal cells and tissues, which are native to that particular anatomic location. Any developmental abnormaly occurring due to such hamartomatous change in the tissue are known as hamartomatous developmental anomalies.
Idiopathic anomalies: Developmental abnormalities of unknown cause are called idiopathic anomalies.
Q 1b. What is the most common developmental malformation in the head and neck region?
Ans. Cleft lip and palate.
Q 1c. What is a lip pit (pit means a large cavity or hole)?
Ans. Lip pit is a developmental anomaly of the lip; which appears as a small depression on the lip either unilaterally or bilaterally.
Q 2. What are the characteristics of lip pits?
Ans. Lip pits are more common among females. They may occur either as isolated entities or may occur in association with cleft lip and/or cleft palate.
Q 3. How the opening of the lip pits clinically appears?
Ans. The opening of the lip pit appears as a circular or transverse slit.
Q 4. Why mucus secretion is often seen from the opening of the lip pits?
Ans. Mucus secretions can be seen from the opening of the lip pit if it is communicating with an underlying minor salivary gland.
Q 5. What are commissural pits (commissure is the area where upper and lower lips join)?
Ans. Commissural pits are developmental anomalies, which appears as a congenital invagination on the labial commissural area.
Q 6. What is double lip?
Ans. Double lip is a developmental anomaly characterized by a horizontal fold of excess or redundant tissue on the mucosal side of the lip (upper lips are mostly affected).
Q 7. How does double lip clinically appear?
Ans. Clinically double lip appears as a cupid’s bow (double curve) when the lip is tense but it is not visible when the lip is at rest. Patient with double lip often shows double vermillion borders when they smile.
Q 8. Double lip is often associated with which syndrome (A syndrome means a group of symptoms, which characterize a disease)?
Ans. Ascher’s syndrome; the features associated with this syndrome include—double lip, dropping of the upper eyelid and non-toxic thyroid enlargement.
Q 9. What is frenal tag (tag means an attachment or a small outgrowth)?
Ans. Frenal tag is the developmental anomaly characterized by a redundant piece of mucosal tissue projecting from the labial frenum.
Q 10. What is Peutz-Jegher’s syndrome?
Ans. Peutz-Jegher’s syndrome is a hereditary condition characterized by gastrointestinal hamartomatous polyposis in association with mucocutaneous pigmentations.
Q 11. What are the clinical manifestations of Peutz-Jegher’s syndrome?
Ans. Brown-black melanin pigmentations on the perioral region, precocious puberty in some cases, intestinal polyposis with abdominal pain and rectal bleeding, etc.
Q 11a. In Peutz-Jegher’s syndrome, the pigmentations occur in which areas?
Ans. It occurs both intraorally as well as extraorally, but mostly in the circumoral area.
Q 11b. In Peutz-Jegher’s syndrome, how the facial pigmentations differ from those of the intraoral areas?
Ans. Intraoral pigmentations are more permanent while the facial pigmentations may fade away in later life.
Q 12. Name the diseases which are often clinically confused with Peutz-Jegher’s syndrome.
Ans. Albright syndrome, Addison’s disease and oral melanotic macule.
Q 12a. Name the diseases, which exhibit cutaneous pigmentations.
Q 13. What is oral melanotic macule (macule means a discolored spot on the mucosa or skin)?
Ans. Oral melanotic macule is an idiopathic, benign pigmented lesion of oral cavity; characterized by increased focal melanin pigmentations in the oral mucosa.
Q 14. What is the clinical appearance of oral melanotic macule?
Ans. Oral melanotic macules clinically appear as small, flat, asymptomatic, brown or black areas over the vermilion border of lip, gingiva and buccal mucosa, etc.
Q 15. What are the histologic features of oral melanotic macule?
Ans. Histologically oral melanotic macule exhibits diffuse accumulations of melanin granules in the basal keratinocytes and in the lamina propria region.
Q 16. What is uvula elongata (elongata means tall or long) and what are the problems it might create?
Ans. Uvula elongata is a developmental anomaly characterized by abnormally long uvula, which touches or hangs lower than the base of the tongue. Sometimes, it may cause coughing or gagging sensations as the elongated uvula touches the epiglottis or the base of the tongue.
Q 17. What is cheilitis glandularis (cheilitis means inflammation of the lip)?
Ans. Cheilitis glandularis is a developmental anomaly characterized by swelling of the lip due to chronic, progressive enlargement of the labial salivary glands.
Q 18. What are the clinical findings in cheilitis glandularis?
Progressive multinodular swelling of the lip with eversion or induration of the surface
Erosion or ulceration in the lip
Occasional crusting and infection.
Q 19. What are the different types of cheilitis glandularis?
Ans. Cheilitis glandularis can be of three types: Simple, superficial ulcerative and deep suppurative types (Table 1.2).
Q 20. What are the chief histological features seen in cheilitis glandularis?
Ans. In cheilitis glandularis, the surface epithelium can be normal or hyperplastic or occasionally dysplastic; underlying minor salivary glands exhibit hypertrophy, inflammation and distention of gland acini with squamous metaplasia of the ductal epithelium.
Q 21. What is cheilitis granulomatosa?
Ans. Cheilitis granulomatosa is a developmental anomaly of lip, which produces a sudden, diffuse painless, nodular swelling of the lip; especially the lower lip.
Q 22. What are the features of Melkersson-Rosenthal syndrome?
Ans. The Melkersson-Rosenthal syndrome constitutes facial paralysis, cheilitis granulomatosa and fissured tongue.
Q 23. Name the common diseases which may be clinically similar to cheilitis granulomatosa.
Ans. Sarcoidosis, angioneurotic edema, Crohn’s disease and cheilitis glandularis, etc.
Q 24. What are Fordyce’s granules?
Ans. Fordyce’s granules are ectopic collections of numerous sebaceous glands within the oral cavity; (ectopic means presence of something in an abnormal position or location) however these glands are generally unassociated with hair follicles.
Q 25. How the Fordyce’s granules appear clinically in the oral cavity?
Ans. Fordyce’s granules clinically appear as multiple, small, discrete, rice-like or milia–like, yellowish-white granules beneath the oral mucosa. They are commonly seen over the cheek, upper lip and gingiva, etc. often in a bilaterally symmetrical pattern.
Q 26. What is the clinical significance of Fordyce’s granules?
Ans. Although these are asymptomatic and apparently harmless entities; however, diseases like sebaceous cysts or adenomas may develop occasionally from the pre-existing Fordyce’s granules.
Q 27. What is focal epithelial hyperplasia (hyperplasia- means increased size of tissue due to increase in number of its constituent cells)?
Ans. Focal epithelial hyperplasia (commonly known as Heck’s disease) is a condition characterized by multiple papillary or sessile hyperplastic areas in the oral mucosa.
Q 28. Describe the clinical appearance of focal epithelial hyperplasia.
Ans. Clinically focal epithelial hyperplasia presents multiple, small, pedunculated, nodular or plaque like soft tissue growths in the labial and buccal mucosa. Occasionally, several hyperplastic lesions may cluster together to produce a typical “Cobblestone” (a naturally rounded stone, larger than a pebble and smaller than a boulder) appearance on the oral mucosa.
Q 29. Describe in brief the histological appearance of focal epithelial hyperplasia.
Ans. Hyperparakeratosis of the surface epithelium with extensive acanthosis (increased thickening of the spinus cell layer) with thickening and elongation of the rete-pegs. The cells of the upper spinus layer often have enlarged nuclei and vacuolated clear cytoplasms (koilocytes).
Q 30. Name the lesions, which look very similar to focal epithelial hyperplasia.
Ans. Leukoplakia, psoriasis, keratoacanthoma and veruciform xanthoma, etc.
Q 31. What is a nevus?
Ans. A nevus can be defined as a congenital, developmental, tumor-like malformation of the skin or mucous membrane.
Q 31a. What is white sponge nevus?
Ans. White sponge nevus is a congenital mucosal abnormality characterized by bilateral, asymptomatic, deeply folded or corrugated, soft or spongy, white lesions in the oral cavity; which affects several members of the same family.
Q 32. What is the other name of white sponge nevus?
Ans. White sponge nevus is also known as Cannon’s disease.
Q 33. Describe the histologic appearance of white sponge nevus.
Ans. Excessive thickening of epithelium with hyperparakeratosis, acanthosis and spongiosis. Intracellular edema in the spinus cell layer with vacuolated cytoplasms and shrunken (pyknotic) nuclei (pyknotic means small or reduced in size).
Q 34. Does white sponge nevus undergo malignant transformation?
Ans. There is no evidence that this lesion undergoes malignant transformation.
Q 35. Name the lesions, which look clinically very similar to white sponge nevus.
Ans. Leukoplakia, hereditary intraepithelial dyskeratosis, lichen planus and candidiasis, etc. (dyskeratosis—premature or abnormal keratinization).
Q 36. What is fibromatosis gingivae?
Ans. Fibromatosis gingivae is a rare hereditary condition characterized by diffuse, non-inflammatory hyperplasia of the gingival tissue.
Q 37. Describe the pathogenesis of fibromatosis gingivae.
Ans. The disease occurs due to diffuse infiltrative hyperplasic proliferation of the fibroblast cells and mature collagen fibers of the gingival tissue.
Q 38. How the gingiva appears clinically in fibromatosis gingivae?
Ans. There will be dense, diffuse, smooth or multinodular, painless, swelling of the gingiva especially in the interdental papilla region. Sometimes, the markedly enlarged gingiva tends to cover the entire crowns of the erupted teeth.
Ans. Cowden’s syndrome is sometimes associated with gingival fibromatosis and the other features of the syndrome include facial trichilemmomas, cobble-stone appearance of oral mucosa, follicular keratosis of facial skin and neoplasm of various types, especially breast cancer.
Q 40. What is retrocuspid papilla?
Ans. Retrocuspid papilla is a developmental anomaly characterized by a slightly raised area of mandibular alveolar mucosa; which as the name implies, is located lingual to the cuspids.
Q 41. What is agnathia?
Ans. Agnathia is the developmental anomaly of jawbone, characterized by complete failure of formation of either maxilla or mandible or even both jaws at a time.
Q 42. What is micrognathia (micro means small)?
Ans. Micrognathia is the anomaly characterized by development of small jaws.
Q 43. What are the types of micrognathia?
Ans. Micrognathia may be of two types—true micrognathia and pseudomicrognathia.
Q 44. What is true micrognathia?
Ans. True micrognathia is the developmental condition where the jawbone is truly and measurably smaller than normal.
Q 45. What is pseudomicrognathia (pseudo means false)?
Ans. Pseudomicrognathia is the condition where a normal sized jaw appears smaller either because it is positioned too much posteriorly in relation to the skull or because the opposing jaw is larger in size.
Q 46. Name few diseases in which micrognathia can occur.
Q 47. What are the common clinical manifestations of micrognathia?
Ans. Patients will have retruded chin and a small face; there will be difficulty in feeding the child, difficulty in proper articulation of words and speech. Dental chances will include improper alignment of teeth with crowding and malocclusion, etc.
Q 48. What is macrognathia (macro means large)?
Ans. Macrognathia is an orofacial anomaly characterized by development of an abnormally large jaw.
Q 49. What are the types of macrognathia?
Ans. Macrognathia can be of two types:
Q 50. What is true macrognathia?
Ans. True macrognathia is the developmental condition in which the jawbone is truly and measurably larger than normal.
Q 51. What is pseudomacrognathia?
Ans. Pseudomacrognathia is the developmental condition, in which a normal sized jaw appears large either because it is placed too much anteriorly in relation to the skull bone or the opposite jaw is smaller in size.
Q 52. Name the conditions which may cause true macrognathia.
Paget’s disease of bone
Q 53. Describe the clinical manifestations of macrognathia.
Ans. Clinically macrognathia presents the following manifestations:
Mandibular protrusion (when lower jaw is affected)
Gummy smile (mostly maxillary)
Ramus of mandible forms a less steep angle with body of the mandible
Excessive condylar growth
Q 54. What is facial hemihypertrophy (hemi means half)?
Ans. Facial hemihypertrophy is a developmental condition characterized by disproportionate unilateral enlargement of the face.
Q 55. What are the clinical features of facial hemihypertrophy?
Unilateral enlargement of the facial soft tissues, bones and teeth
Both upper and lower jaws are enlarged on the affected side while the other side is normal
The ear and the eye on the affected side may be enlarged
Skin on the affected side of face is thick and coarse with hypertrichosis (hypertrichosis means—excessive growth of hair)
Teeth on the affected side may often erupt prematurely
Tongue is larger in one side with enlarged papillae.
Q 56. What is facial hemiatrophy (atrophy means decrease in size of a tissue due to decrease in the size of its constituent cells)?
Ans. Facial hemiatrophy is a developmental anomaly, which is just opposite to facial hemihypertrophy and is characterized by progressive decrease in the size of one side of the face.
Q 57. What is the other name of facial hemiatrophy?
Q 58. Describe the clinical features of facial hemiatrophy.
One side of the face appears smaller than the other side
The skin, muscles and bone all are atrophic on the affected side
The cheek looks hallowed and eyes appear depressed
Teeth on the affected side are smaller in size
Delayed eruption of teeth on the affected side.
Q 58a. What is a torus palatinous?
Ans. It is a developmental bony overgrowth seen in the hard palate.
Q 58b. What is a torus mandibularis?
Ans. It is a developmental bony overgrowth that occurs bilaterally on the inner aspect of mandible above the myelohyoid line.
Q 59. What are the most common developmental defects in the orofacial region?
Ans. Cleft lip and cleft palate (cleft means split or divided).
Q 59a. What is mosaicism in genetics?
Ans. It is the differential expression of same gene depending on the parent of origin.
Q 60. Name the common clefts in the orofacial region.
Clefts of the primary palate
Cleft of the secondary palate
Oblique facial cleft
Submucosal cleft palate
Pits of the lip.
Q 60a. Define cleft lip.
Ans. Cleft lip is a congenital developmental anomaly characterized by a ‘wedge-shaped’ defect or cut in the lip; which is more often seen in the upper lip.
Q 61. Define cleft palate.
Ans. It is a developmental defect of palate characterized by lack of complete fusion between two lateral halves of the palate resulting in a cleft. Cleft in the palate leads to communication between oral and the nasal cavity.
Q 62. What are the common causes of orofacial clefts?
Ans. Hereditary cause and environmental cause.
Q 62a. How heredity plays a role in the development of cleft lip and cleft palate?
Ans. Heredity is the most important single factor in the development of cleft lip and cleft palate. There can be either defect in multiple genes (polygenic influence) or defect in any single gene (monogenic influence).
Q 62b. Name the environmental factors responsible for development of cleft lip and cleft palate.
Nutritional factors such as deficiency of or excess of vitamin A and deficiency of riboflavin
Maternal smoking (during pregnancy)
Psychogenic, emotional or traumatic stress in pregnant mothers
Relative ischemia to the area due to defective vascular supply
Mechanical obstruction by enlarged tongue
High dose of steroid therapy during pregnancy
Substances such as alcohol, drugs or toxins in the circulation.
Q 62c. How clefts develop in the upper lip or premaxilla?
Ans. Cleft of the upper lip and premaxilla occur due to failure of mesodermal penetration and subsequent obliteration of the ectodermal grooves between the median nasal process, lateral nasal process and the maxillary process.
Q 62d. Unilateral cleft in the upper lip occurs due to failure of fusion between?
Ans. Median nasal and maxillary process.
Q 63. How does isolated cleft palate develop?
Ans. An isolated cleft in the palate develops due to failure of fusion between two palatal shelves in the midline.
Q 64. How the failure of growth of mandible and subsequent movement of tongue can result in cleft palate?
Up to the 8th week of intra uterine life the tongue lies between two palatal shelves of the growing upper jaw; however, during ninth and tenth week of intra uterine life the tongue gradually moves downwards as the mandible enlarges and this allows rotation and subsequent fusion of the two palatal shelves.
If the mandible fails to grow and does not make a downward progress during the intra-uterine life, then the tongue remains static between the two palatal halves and this restricts the fusion two palatal shelves; resulting in cleft palate.
Q 65. What is the incidence rate of cleft lip and cleft palate?
Ans. The incidence rate ranges between 1 in 500 and 1 in 2500 childbirths.
Q 65a. What is the most common type of cleft among males?
Ans. Cleft lip and cleft palate.
Q 65b. What is the most common type of cleft among females?
Ans. Cleft palate alone.
Q 65c. In case of cleft lip, which side of the face is commonly affected?
Q 66. What is the Davis and Ritchie classification of cleft lip and cleft palate?
Ans. According to Davis and Ritchie, cleft lip (CL) and cleft palate (CP) is classified in the following way:
Group I: Clefts anterior to the alveolus(unilateral, median, or bilateral CL)
Group II: Post-alveolar clefts (CP alone, soft palate alone, soft palate and hard palate, or submucous cleft).
Table 1.3 shows classification of cleft up and cleft palate.
Q 67. Describe the Veau classification of cleft lip and cleft palate.
Ans. The Veau classification of cleft lip and cleft palate is as follows:
Group I (A): Defects of the soft palate only
Group II (B): Defects involving the hard palate and soft palate
Group III (C): Defects involving the soft palate to the alveolus, usually involving the lip
Group IV (D): Complete bilateral clefts.
Q 68. Describe the Kernahan and Stark symbolic classification of cleft lip and cleft palate.
Ans. The Kernahan and Stark symbolic classification of cleft lip and cleft palate is as follows:
Areas 1 and 4: Lip
Areas 2 and 5: Alveolus
Areas 3 and 6: Palate between alveolus and the incisive foramen
Areas 7 and 8: Hard palate
Area 9: Soft palate.
Q 69. What is the International Confederation of Plastic and Reconstructive Surgery Classification of cleft lip and cleft palate?
Ans. According to the International Confederation of Plastic and Reconstructive Surgery the cleft lip and cleft palate is classified in the following way:
Group II: Clefts of the secondary palate (hard palate, soft palate, or both)
Group III: Any combination of clefts involving the primary and secondary palates.
Q 69a. Which type of cleft lip is seen more often?
Ans. Unilateral complete type.
Q 70. What are clinical features of cleft lip and cleft palate?
Ans. Cleft lip and cleft palate clinically presents the following features:
Difficulty in breastfeeding
Nasal regurgitation of food/drinks
Retrusion of maxilla with narrow arched palate (retrusion means—towards the back)
Defective phonation (speech)
Presence of deformity, displacement and impaction of upper anterior teeth
Deflection of nasal tip towards the non-cleft side.
Q 71. Why breastfeeding is difficult to the babies having cleft palate?
Ans. Breastfeeding is difficult to babies having cleft lip or cleft palate, as they cannot generate sufficient suction while sucking milk.
Q 72. Why nasal regurgitation of drinks occurs in case of cleft lip or cleft palate (regurgitation means bringing out swallowed food)?
Ans. As cleft palate creates a communication between the oral and the nasal cavities, when ever patients try to take food or liquid it comes out through nose which is called as nasal reflux or regurgitation.
Q 73. What is the mildest form of cleft palate (mild means little or slight)?
Ans. The mildest form of cleft palate is when the cleft is involving only the uvula.
Q 74. What is the worst form cleft lip and cleft palate?
Ans. Bilateral complete cleft lip with cleft palate is the worst situation where complete separation of the anterior palate occurs, which projects towards the mid portion of the lip and is attached only by the nasal septum.
Q 75. When should a child of cleft lip be ideally treated?
Ans. Cleft lip is treated surgically in the first week after birth, when the blood hemoglobin level is high and the kid is protected by the maternal antibodies. However, sometimes the surgery may be deferred until the baby attains 2 to 3 months of age, as by this time, the infant becomes adapted to its independent existence.
Q 76. When should a child of cleft palate be ideally treated?
Ans. Generally cleft palates are corrected surgically at the age of 18 months or immediately after that. This particular time is selected, since after this age there will be development of speech and any further delayed in treatment will cause abnormal speech development.
Q 76a. Speech retardation may be considered if the child does not speak by what age (retarded means stopped or slowed down)?
Ans. 24 months of age.
Q 77. What is an obturator?
Ans. Obturator is a prosthesis, which is given in untreated adult patients with cleft palate. The appliance helps in keeping the palatal clefts closed and thereby helps in speech and taking food.
Q 78. Name some common syndromes associated with cleft palate.
Median cleft face syndrome
Oral facial digital syndrome
Q 79. What is aglossia?
Ans. Aglossia is a developmental anomaly which means complete absence of tongue.
Q 80. What is microglossia?
Ans. Microglossia is the developmental anomaly in which the tongue is very small or rudimentary in size.
Q 81. What are the clinical symptoms associated with microglossia?
Difficulty in sucking milk by the child
Smaller mandibular arch
Q 81a. Do patients with microglossia have severe speech difficulties or difficulty in taking food?
Ans. Patients with microglossia generally don’t have severe speech difficulties or difficulty in taking food.
Q 82. What is macroglossia?
Ans. Macroglossia is a relatively common developmental disorder in which the tongue is abnormally large in size.
Q 83. What are the causes of macroglossia?
Ans. The causes of macroglossia are divided into two broad groups—congenital causes and acquired causes.
Q 84. Mention the congenital (patient born with the disease) causes of macroglossia.
Idiopathic muscular hypertrophy of tongue (idiopathic means cause is unknown)
Lysosomal storage disease, e.g. Hurler’s syndrome and Hunter’s syndrome
Beckwith’s hypoglycemic syndrome
Multiple endocrine neoplasia syndrome
Lingual thyroid nodule
Gargolysm (hereditary defect of mucopolysaccharide metabolism)
Neonatal diabetes mellitus (neonatal means—newborn; neonatal period—first 28 days of life).
Q 85. Mention the acquired (patient had the disease after birth) causes of macroglossia.
Infiltrative diseases of tongue, e.g. amyloidosis and sarcoidosis.
Systemic conditions, e.g. uremia and iatrogenic factors (iatrogenic means problem developed in a patient as a result of some treatment)
Traumatic conditions of tongue, e.g. surgery, hemorrhage, tongue biting, intubation injury and radiation injury, etc.
Endocrine disorders, e.g. acromegaly, cretinism, hypothyroidism, diabetes and myxedema, etc.
Lymphatic obstruction of tongue due to any malignant tumor
Inflammatory conditions in the tongue, e.g. syphilis, Ludwig’s angina, tuberculosis, scurvy, actinomycosis and pellagra, etc.
Cystic lesions of tongue, e.g. dermoid and epidermoid cyst.
Q 86. What is relative macroglossia?
Ans. Relative macroglossia is a condition in which a normal sized tongue appears large, especially in those cases where actual size of the mouth is small.
Q 87. Mention few conditions in which relative macroglossia may be seen.
Ans. Maxillary retrusion, restricted growth of nasopharynx (part of pharynx above the soft palate that is continuous with the nasal passages), enlarged tonsils or adenoids, mandibular retrognathism, low palate with reduced volume of oral cavity and habitual forward positioning of tongue, etc.
Q 88. What is the commonest cause of macroglossia?
Ans. Development of lymphangioma in the tongue.
Q 89. What is apparent macroglossia?
Ans. Apparent macroglossia is a condition where the tongue appears abnormally large due to its poor muscular control, although there is no real increase in the bulk of the tongue tissue. Apparent macroglossia is often seen in cretinism and in Happy puppet syndrome.
Q 90. Mention the clinical manifestations of macroglossia.
Difficulty in speech and eating food
Pressure on the teeth with diastema formation
Indentations can be seen on the lateral borders of tongue
Blockage of the pharyngeal airway due to macroglossia may result in a condition called obstruction sleep apnea.
Q 90a. Name one syndrome which is associated with macroglossia.
Ans. Beckwith’s hypoglycemic syndrome (which also includes features like neonatal hypoglycemia, mild microcephaly, umbilical hernia, high birth weight and postnatal somatic gigantism, etc).
Q 91. What is ankyloglossia (ankylosis means abnormal adhesion or immobility)?
Ans. Ankyloglossia or tongue tie can be defined as a congenital developmental condition characterized by fixation of the tongue to the floor of the mouth; causing restricted tongue mobility.
Q 92. What are the types of ankyloglossia?
Ans. Ankyloglossia may be of two types—partial or complete.
Q 93. What is partial ankyloglossia?
Ans. When the tongue is partially fixed to the floor of the mouth it is called partial ankyloglossia or tongue tie; in this condition slight functional movement of the tongue is possible.
Q 94. What is complete ankyloglossia?
Ans. When the tongue is completely fixed to the floor of the mouth with no functional movement it is called complete ankyloglossia.
Q 95. How can it be checked if a patient has tongue tie or not?
Ans. Under normal circumstances the patient should be able to touch the anterior palate with the tip of his or her tongue: but in ankyloglossia the tip of tongue will not reach up to that limit.
Q 96. What are the clinical signs and symptoms of ankyloglossia?
Difficulty in pronunciation of certain consonants and diphthongs such as L, R, T, D, N, TH, SH, Z etc. (diphthong means a gliding vowel in the articulation of which there is a continuous transition from one position to another)
Infants feel difficulty in sucking breast milk
Deformities in dental occlusion especially development of open bite and mandibular prognathism
Difficulty in swallowing food, taking ice-creams and maintaining the oral hygiene
Tension in the anterior lingual gingival with development of gingival recession and diastema (gap between teeth) formation between lower incisor teeth.
Q 97. What is cleft tongue?
Ans. It is a congenital developmental disturbance characterized by partial or complete cleft in the tongue.
Q 98. How cleft tongue develops?
Ans. Cleft tongue usually develops due to partial or complete failure of union between the two lateral lingual swellings during embryogenesis.
Q 99. What are the types of cleft tongue?
Ans. Cleft tongue may be partial in which there is a deep groove in the midline of the tongue or it may be a complete type in which the tongue shows a complete cut along the long axis.
Q 100. What are the clinical problems associated with cleft tongue?
Ans. Cleft tongue is mostly asymptomatic, although sometimes irritation can be felt due to accumulation of food debri or microorganisms at the bottom of the cleft.
Q 101. What is a fissured or scrotal tongue (fissure means crack or cleft or split)?
Ans. Fissured tongue is a congenital developmental malformation; characterized by presence of numerous shallow or deep groves (fissures) on the dorsal and lateral surface of the tongue.
Q 102. What are the clinical features of fissured tongue?
Presence of several fissures or groves on the tongue
The fissures often radiate from a central groove on the dorsal surface of tongue in an oblique direction (Groove means a long, narrow cut or depression)
The average depth of these groves is about 6 millimeter
It is mostly an asymptomatic condition
However, collection of food debris and microorganisms in these fissures or groves may sometimes cause discomfort.
Q 103. Name the syndrome which is often associated with fissured tongue.
Ans. Fissured tongue is often associated with Melkersson-Rosenthal syndrome and the other features of the syndrome include cheilitis granulomatosa and facial paralysis.
Q 104. What is median rhomboid glossitis (rhomboid—having shape of a rhombus)?
Ans. Median rhomboid glossitis is a developmental anomaly characterized by the presence of an asymptomatic, elongated, erythematous patch of atrophic mucosa on the middorsal surface of the tongue.
Q 105. Why median rhomboid glossitis develops?
Ans. It presumably develops due to persistence of the tuberculum impar on the surface of dorsum of the tongue during the development of tongue.
Recent investigators however believe that median rhomboid glossitis is not a developmental anomaly and it occurs due to chronic infection of tongue by the fungus (candida albicans).
Q 106. Describe the clinical appearance of median rhomboid glossitis?
Ans. Median rhomboid glossitis clinically appears as a diamond or lozenge shaped depapillated area located along the median fissure on the dorsum of the tongue just anterior to the circumvallate papilla.
Q 107. What are the symptoms of median rhomboid glossitis?
Ans. Median rhomboid glossitis appears pale pink or bright red in color, there may be occasional soreness in the area otherwise it is asymptomatic; however, patients often mistake it as tongue cancer due to its suspicious look.
Q 108. What is geographic tongue?
Ans. Geographic tongue or benign migratory glossitis is a common developmental anomaly characterized by multifocal, patchy irregular area of depapillation of tongue characterized by frequent remissions and recurrences.
Q 108a. What are the other names of geographic tongue?
Ans. Benign migratory glossitis or erythema migrans.
Q 109. How geographic tongue clinically appears?
Ans. Geographic tongue clinically presents multiple, irregular, well-demarcated, erythematous areas on the dorsum of the tongue with desquamation of the filliform papilla. The border of the lesion is surrounded by a slightly raised, yellowish–white line and within the lesion the fungiform papillae appear as elevated, red dots.
Ans. Filliform papilla.
Q 110. Why geographic tongue is called migratory glossitis?
Ans. In geographic tongue there is desquamation of fillifom papilla at multiple locations on the dorsum of the tongue; the initial lesions heal up in a few days time but they reappear again at newer locations every time. As the lesions apparently exhibit a sense for migration from one area to the other; the disease is called migratory glossitis.
Q 110a. Which tongue anomaly may be associated with geographic tongue very often?
Ans. Scrotal tongue.
Q 111. What is black hairy tongue?
Ans. Hairy tongue is a developmental anomaly characterized by hypertrophy of the filliform papilla of tongue along with loss of normal desquamation process; which leads to an abnormal hair-like growth of the papilla with formation of a pigmented, thick, matted layer on the tongue surface.
Q 112. Name the factors which help in the development of black hairy tongue.
Poor oral hygiene
Prolonged use of antibiotics
Q 113. Describe the clinical appearance of black hairy tongue.
Ans. There is hypertrophy and elongation of the filliform papilla of tongue, some of which may be as long as half a centimeter; once these enlarged papillae are mixed up with food debris and microorganisms they produce a thick, matted layer on the dorsal surface of tongue. Hairy tongue may produce halitosis and gagging sensations.
Q 113a. Which papillae are enlarged in black hairy tongue?
Ans. Filliform papilla.
Q 114. What is lingual thyroid nodule?
Ans. Accessory accumulation of functional thyroid gland tissue within the body of the tongue is called lingual thyroid nodule.
Q 114a. What is foramen cecum?
Ans. It is the remnant of thyroglossal tract in the tongue.
Q 115. How lingual thyroid nodule develops?
Ans. The thyroid gland normally develops at the site of foramen cecum of tongue during embryogenesis and afterwards it migrates inferiorly along the thyroglossal tract to its ultimate destination in the antero lateral surface of the trachea in the anterior neck. However, if all or part of the thyroid analog fails to migrate after the initial development, then lingual thyroid nodule develops.
Q 116. How lingual thyroid nodule clinically manifests?
Ans. The lingual thyroid nodule clinically presents a deep seated, nodular, exophytic mass on the tongue, measuring about 2 to 3 cm in diameter and is located posterior to the foramen cecum mostly in the midline.
Q 116a. What symptoms are produced by lingual thyroid nodule.
Ans. Sometimes it can produce change of voice (dysphonia), bleeding, pain, difficulty in swallowing (dysphagia), respiratory obstruction (dyspnea) and a feeling of tightness in the throat, etc.
Q 117. What is a thyroglossal tract cyst?
Ans. The thyroglossal tract cyst is an uncommon developmental cystic lesion arising from the embryonic remnants of the thyroglossal tract.
Q 118. What is the typical location of thyroglossal tract cyst?
Ans. The cyst is located on the midline of the neck, anywhere between the base of the tongue above and the thyroid gland below; however, most of the cysts develop below the hyoid bone.
Q 119. Describe the clinical appearance of thyroglossal tract cyst.
Ans. The cyst presents a slow enlarging, asymptomatic mobile swelling in the midline of anterior neck above the thyroid gland.
Q 120. What is lymphoepithelial cyst?
Ans. Lymphoepithelial cyst (previously called branchial cyst) is a developmental cystic lesion of uncertain pathogenesis.
Q 121. What is the common location of lymphoepithelial cyst?
Ans. The most common location of lymphoepithelial cyst is the lateral aspect of the neck; anterior to the sternomastoid muscle; few lesions occur intraorally.
Q 122. What is the typical clinical appearance of lymphoepithelial cyst?
Ans. Lymphoepithelial cyst generally presents as an asymptomatic, circumscribed, movable swelling on the lateral aspect of the neck anterior to the sternomastoid muscle.
Q 123. What is microdontia?
Ans. Microdontia is the condition in which the teeth in the jaws are smaller than normal in size.
Q 124. What are the types of microdontia?
Ans. Microdontia may be of two types—generalized microdontia and localized or focal microdontia. Moreover, microdontia can also be divided into two more types—true microdontia and relative microdontia.
Q 124a. What is true microdontia?
Ans. When teeth in the jaw are truly and measurably smaller than normal in size the condition is called true microdontia.
Q 124b. What is relative microdontia?
Ans. Relative microdontia is the condition in which teeth of normal size may look smaller because the size of the jaw is larger.
Q 125. What is generalized microdontia?
Ans. Generalized microdontia is the condition in which all the teeth in the mouth are smaller than normal in size.
Q 125a. What is true generalized microdontia?
Ans. When all the teeth in upper and lower jaw are uniformly and measurably smaller than normal in size the condition is known as true generalized microdontia.
Q 125b. What is relative generalized microdontia?
Ans. Relative generalized microdontia is the condition in which all normal sized teeth in the jaw will look smaller as they are placed in an abnormally large maxilla and mandible. In other words larger size of the jaw makes an illusion of microdontia although the teeth are not really smaller in size.
Q 126. What is localized or focal microdontia?
Ans. Localized or focal microdontia is the condition in which one or few teeth in the mouth are smaller than normal in size.
Q 126a. Name the permanent anterior tooth that most often shows variation in size.
Ans. Maxillary lateral incisor.
Q 127. Name some conditions which are associated with microdontia.
Ans. Hereditary ectodermal dysplasia, dens-invaginatus, cleft lip and cleft palate, facial hemiatrophy, congenital syphilis and supernumerary teeth, etc.
Q 127a. Which tooth most often exhibits microdontia?
Ans. Maxillary lateral incisor.
Q 127b. Name few teeth which often show macrodontia.
Ans. Maxillary lateral incisors and maxillary third molars are most commonly affected; however maxillary and mandibular second premolars are also sometimes affected.
Q 127c. In microdontia, which tooth is most commonly affected?
Ans. Maxillary permanent lateral incisor.
Q 128. What are the clinical problems associated with microdontia?
Ans. Microdontia may cause spacing between teeth, cosmetic problems, food impaction with increased susceptibility to caries formation and periodontal problems, disturbance in speech and problems in chewing, etc.
Q 129. What is macrodontia?
Ans. Macrodontia is a condition in which size of the teeth in the jaws are measurably larger than normal.
Q 130. What is true generalized macrodontia?
Ans. When all the teeth in both jaws are truly and measurably larger than normal in size, the condition is termed as true generalized macrodontia.
Q 131. What is relative macrodontia?
Ans. Relative macrodontia is the condition in which teeth of normal size appear larger because of the smaller size of jawbone.
Q 132. What is focal macrodontia?
Ans. Focal or localized macrodontia is the condition in which a single or few teeth are larger in size as compared to the remaining teeth in mouth.
Q 133. Name the conditions in which, macrodontia frequently occurs.
Ans. Pituitary gigantism, fused teeth, gemination of tooth and facial hemihypertrophy, etc.
Q 134. Macrodontia of single tooth is most frequently seen in which region of dental arch?
Ans. Incisor areas.
Q 135. Define anodontia (ano means nil).
Ans. Anodontia can be defined as a condition in which there is congenital absence of teeth in the mouth.
Q 136. What are the types of anodontia?
Ans. Anodontia can be of the following types:
Q 136a. What is the other name of anodontia?
Ans. Anodontia is also known as oligodontia or hypodontia (oligo means little or small).
Q 137. What is true anodontia?
Ans. True anodontia refers to genuine absence of tooth in mouth due to lack of formation of tooth in the jaw.
Q 138. What is pseudoanodontia?
Ans. Pseudoanodontia is the condition in which teeth are actually present in the jaw but are not erupted and hence are not visible in the mouth.
Q 139. Give few examples where pseudoanodontia is seen?
Ans. Impacted teeth or submerged teeth.
Q 140. Name some conditions where true anodontia often occurs.
Hereditary ectodermal dysplasia
Radiation injury during childhood
Cleft lip and cleft palate
Q 141. Name the teeth which are often missing in case of anodontia.
Among the permanent teeth—third molars, maxillary lateral incisors and mandibular premolars, etc.
Among the deciduous teeth—maxillary lateral incisors.
Q 141a. Which individual tooth is missing most often in case of anodontia?
Ans. Mandibular second premolar.
Q 142. Name the teeth which are least likely to be missing in anodontia.
Ans. Mandibular first molars and mandibular lateral incisors.
Q 143. What are the common clinical problems associated with anodontia?
Ans. Disturbance in chewing food and speech, cosmetic problems or poor look, food impaction with increased susceptibility to caries and periodontal disease, malocclusion and failure of growth of alveolar bone in the area where the tooth or teeth are missing.
Q 144. What is a supernumerary tooth (Supernumerary means present in excess of the normal or requisite number)?
Ans. Presence of any extra tooth in the dental arch, in addition to the normal series of teeth (i.e. 20 in deciduous dentition and 32 in permanent dentition) is known as supernumerary teeth.
Q 145. When supernumerary teeth are present in the mouth, the condition is called?
Ans. The condition is called hyperdontia or polydontia.
Q 146. What are the possible causes of development of supernumerary teeth?
Heredity: These are more commonly seen among the family members of the affected individual as compared to the general population
Dichotomy (division into two) of the tooth bud
Localized conditioned hyperactivity of the dental lamina
Fragmentation of the dental lamina during development of cleft lip and cleft palate.
Q 147. How supernumerary tooth develops?
Ans. Supermumerary tooth develops either from the accessory tooth bud in the dental lamina or from splitting of a regular normal tooth bud during odontogenesis.
Q 148. Supernumerary teeth develop more often in relation to maxilla or mandible?
Ans. These are more commonly seen in relation to maxilla.
Q 149. Which dentition is more often affected by supernumerary teeth?
Ans. These are more often seen in permanent dentition and rarely seen in deciduous dentition.
Q 149a. Maximum supernumerary teeth develop in which jaw, and of which dentition?
Ans. Maxillary jaw and permanent dentition.
Q 150. Name the different types of supernumerary teeth.
Ans. Supernumerary teeth may be of several types, which are as follows:
According to the site of development:
According to the morphology:
Conical type (often peg shaped)
Tuberculate type (contains more than one cusp or tubercle)
Supplemental type (duplicates any normal tooth but much smaller in size)
Odontome associated type (occurs as miniature teeth in relation to odontomes).
Q 151. What is a mesiodens?
Ans. Mesiodens are the most common of all supernumerary teeth and these are located in the midline, on the palatal aspect, between the roots of two upper central incisors.
Q 152. What is a distomolar?
Ans. Distomolar is a supernumerary tooth which is usually present on the distal aspect of normal molar teeth in the dental arch.
Q 153. What is a paramolar?
Ans. Paramolar is a supernumerary tooth which develops either on the buccal or the lingual aspect of normal molar teeth in the dental arch.
Q 154. How the supernumerary teeth appear in the mouth?
Ans. Supernumerary teeth can be either single or multiple in number, they may be impacted or erupted and may occur either unilaterally or bilaterally in the dental arch. These teeth are mostly small, often morphologically deformed and miniature type.
Q 154a. When supernumerary teeth erupt in the mouth?
Ans. These teeth may erupt either before or after the eruption of the normal teeth.
Q 154b. Name the problems often caused by the supernumerary teeth.
Crowding of teeth in the dental arch
Obstruction in the path of eruption of any normal tooth
Increased caries incidence and periodontal problems
Rotation or protrusion of teeth
Displacement of the normal teeth in the jaw
May be associated with dentigerous cyst.
Q 154c. Name few conditions which are associated with supernumerary teeth.
Cleft lip and cleft palate
Q 154d. What are accessional teeth?
Ans. Teeth those have no deciduous predecessors are called accessional teeth, e.g. the permanent molars.
Q 154e. What are successional teeth?
Ans. The permanent teeth those have deciduous predecessors are called successional teeth, e.g. all teeth other than permanent molars.
Q 154f. Which teeth are called cuspids and which are called bicuspids?
Ans. The canine teeth are called cuspids while the premolars are called bicuspids.
Q 154g. Which tooth is called ‘eye tooth?
Ans. A canine tooth of the upper jaw is also called an eye tooth.
Q 154h. Which tooth is also called stomach tooth’?
Ans. A canine tooth of the lower jaw is also known as a stomach tooth.
Q 155. What is premature eruption of tooth?
Ans. Premature eruption can be defined as a situation when a tooth erupts into the oral cavity much ahead of its normal time of eruption.
Q 156. What are the examples of premature eruption of tooth?
Ans. Natal teeth and neonatal teeth; these are not supernumerary teeth but are part of the regular component of deciduous dentition.
Q 156a. What is transposition of teeth?
Ans. When two teeth change their position in the jaw or are put into different places or order; the condition is called tooth transposition.
Q 156b. Which are the commonest teeth involved in transposition?
Ans. Overall, the most common transposition occurs between maxillary canine and first premolar.
Q 157. What is a natal tooth?
Ans. Natal tooth is an erupted deciduous tooth which is present at birth.
Q 158. What is a neonatal tooth?
Ans. Neonatal tooth is a deciduous tooth which erupts during the first 28 days of life.
Q 159. Which teeth exhibit premature eruption more often than others?
Ans. Deciduous mandibular central incisors.
Q 160. Name the systemic condition in which premature eruption of all permanent teeth occurs?
Q 160a. A mother complaining that her daughter’s lower permanent anterior teeth are coming from lingual aspect of the deciduous anteriors, what treatment is suggested?
Ans. No treatment is needed as this is a normal phenomenon.
Q 160b. Which deciduous tooth exfoliates last of all?
Ans. Maxillary canine.
Q 161. What is delayed eruption?
Ans. Delayed eruption refers to the first appearance of teeth in the oral cavity at a much later time than what is normally expected.
Q 161a. Will the alveolar bone develop if no tooth erupts in mouth?
Q 162. Name the systemic conditions associated with delayed eruption of tooth.
Decreased secretion of growth hormone
Radiation therapy of the jaw in early life
Fetal alcohol syndrome.
Q 163. What are the local factors associated with delayed eruption of tooth?
Obstruction from an impacted tooth or a supernumerary tooth
Obstruction from a tumor or cyst in the jaw
Abnormal position of the crypt
Retained deciduous teeth
Cleft lip and cleft palate
Premature loss of primary teeth
Fracture of jaw during the time of eruption of tooth
Crowding of teeth.
Q 164. What is impaction of tooth?
Ans. Impaction is defined as the cessation of eruption of tooth caused either by a clinically and radiographically detectable physical barrier in the eruption path or by ectopic positioning of the involved tooth.
Q 165. What are the causes of impaction of tooth?
Ans. Micrognathia, malocclusion, rotation of tooth, retained deciduous tooth, supernumerary tooth, cysts or tumors in the jaw, cleidocranial dysplasia and Gardner’s syndrome, etc.
Q 166. Name the teeth which may be commonly impacted.
Commonest teeth to be impacted: mandibular and maxillary third molars
Second next common teeth: mandibular second premolars and maxillary canines
The supernumerary teeth.
Q 167. What are the different types of tooth impaction?
Q 168. What is complete impaction?
Q 169. What is partial impaction of tooth?
Ans. When an impacted tooth is partly enclosed by bone and partly covered by the gingival soft tissue, it is called a partial impaction of tooth.
Q 170. What is a submerged tooth?
Ans. When there is cessation of eruption of a deciduous tooth after gingival emergence it is called a submerged tooth. The occlusal surface of this tooth lies just above the gingiva but much below the occlusal plane of the remaining permanent teeth.
Q 170a. Which teeth are more often submerged?
Ans. Mandibular deciduous second molars.
Q 171. What is an embedded tooth?
Ans. When an individual tooth fails to erupt for no apparent reason it is called an embedded tooth. The tooth lies below the gum line and there is no physical barrier present as may be seen in case of impaction.
Q 172. What is mesioangular impaction?
Ans. When the long axis of an impacted tooth is inclined mesially (towards the midline of dental arch) in respect to the remaining teeth in the jaw.
Q 173. What is distoangular impaction?
Ans. When the long axis of an impacted tooth is inclined distally (away from the midline of dental arch); in respect to the remaining teeth in the jaw.
Q 173a. Which type of impaction is more common between mesio and distoangular variety?
Ans. Mesioangular impaction is more common.
Q 174. What is horizontal impaction?
Ans. Horizontally impacted teeth lies parallel to the long axis of the jaw bone.
Q 175. Name the common X-rays used in the diagnosis and evaluation of impacted teeth.
Intraoral periapical radiographs (IOPA)
Panoramic radiograph (orthopantomogram)
Right and left oblique lateral radiograph of the jaw
Standard occlusal radiograph
Paranasal sinus view radiographs.
Q 176. Name the possible clinical manifestations of tooth impaction.
Recurrent infection, pain and swelling in the jaw
Increased risk of periodontal diseases
Increased risk of caries in adjacent teeth
Predisposition of dentigerous cyst development (predispose means to make something liable)
May precipitate development of tumor in the jaw (precipitate means cause to happen something suddenly or unexpectedly)
Unusual presence within the maxillary antrum
Weakness in the jaw bone and increased risk of fracture
May predispose to the development of osteomyelitis, cellulites and space infections, etc.
Q 177. What is eruption sequestrum (a sequestrum is a piece of dead bone that has become separated from normal or healthy bone during the process of necrosis)?
Ans. A small fragment of necrosed bone is sometimes seen overlying an erupting tooth which is called eruption sequestrum. This type of bone fragment is probably detached from the alveolar ridge during the emergence of the erupting tooth outside gingiva.
Q 177a. Name the anomalies of tooth, which develop during the stage of morphodifferentiation.
Q 178. What is gemination of tooth? (gemination means doubling)
Ans. Gemination is a developmental anomaly characterized by a partial cleavage in a single tooth germ resulting in the formation of two partially separated crowns and one root.
Q 179. What is twinning (twinning means formation of a twin)?
Ans. The term twinning refers to complete and equal division of a single tooth germ into two; it result in the formation of one normal and one supernumerary tooth.
Q 180. In case of gemination, which teeth are most commonly affected?
Ans. Gemination mostly affects deciduous mandibular incisors and permanent maxillary incisors.
Q 181. What is fusion of tooth?
Ans. Fusion can be defined as the union of two adjacent normally separated tooth germs at the level of dentine during tooth development.
Q 182. Describe the characteristics of fusion of tooth.
Ans. Fusion results in one anomalous large tooth formation in place of two normal regular sized teeth and the tooth have either a single enlarged root or two roots.
Q 182a. Fusion of tooth more often affects which dentition?
Q 183. What is the most important criteria of fusion of tooth?
Ans. The most important criteria for fusion are that the fused teeth must exhibit confluent dentin.
Q 184. How do we differentiate between gemination, twining and fusion?
Ans. The differentiation can be made simply by counting the number of teeth in the dental arch.
Full complement or number of teeth are present in the dental arch in case of gemination
One extra tooth is present in the jaw in case of twinning
One regular tooth will be missing from the dental arch in fusion.
Q 185. What is concrescence (concrescence means coalescence or growing together of parts originally separate)?
Ans. Concrescence is a developmental anomaly characterized by union of roots of two or more adjoining completely formed teeth along the line of cementum.
Q 186. How concrescence occurs?
Ans. Concrescence probably occurs as a result of traumatic injury to the jaw, which causes loss of interdental bone and brings roots of the neighboring teeth in close proximity to one another. Finally fusion occurs between the roots of two or more separate teeth due to deposition of cementum between them.
Q 187. Which teeth are often joined together in case of concrescence?
Ans. Permanent maxillary molars are more often joined in case of concrescence (because roots of these teeth are anatomically placed very closed to one another).
Q 188. What is the best way to diagnose concrescence?
Ans. In case of concrescence, clinically the teeth look normal and unsuspecting; therefore, it is best diagnosed with the help of radiographs, which reveal obliteration of periodontal ligament space in the inter-radicular areas of the involved teeth.
Q 189. What is the clinical significance of concrescence?
Ans. In undiagnosed cases attempted extraction of the affected tooth may cause trauma to the jaw or may result in removal of many teeth instead of one.
Q 190. What is dilaceration?
Ans. Dilaceration is a developmental anomaly in the shape of tooth; which is characterized by a sharp bend or a curve either in the root or in the crown of a formed tooth.
Q 191. How dilaceration develops in a tooth?
Ans. It is generally believed that injury to the deciduous tooth with subsequent pressure on the developing permanent tooth may cause displacement of the hard calcified portion of the later away from its normal axis and later on, the unclassified portion of the said permanent tooth develops with an unusual angulation.
Q 192. What is the best way to diagnose dilaceration and how does the tooth appear in it?
Ans. Dilaceration can best be diagnosed with the help of radiographs and the tooth typically appears hook shaped due to bending in the root.
Ans. Dilaceration in a tooth must be detected by radiographs and care should be taken while extracting such teeth since these are more prone to fracture.
Q 194. What is taurodontism (tauro means bull)?
Ans. Taurodontism or bull-like tooth is a peculiar developmental condition in which, the crown portion of the tooth is enlarged at the expense of its roots.
Q 195. Why taurodontism develops?
Ans. The condition probably develops due to failure of the Hertwig’s root sheath to invaginate at the proper horizontal level during tooth development.
Q 196. Describe the clinical appearance of a tooth with taurodontism.
Ans. The affected tooth in taurodontism is often rectangular in shape with large crown, elongated pulp chamber and short rudimentary root. The tooth also has minimum constriction at the cervical area and moreover the furcation area of the tooth is more apically placed than normal.
Q 196a. What are the principal features of taurodontism?
Ans. Enlarged tooth crown, large pulp and short roots.
Q 197. Name the teeth which are commonly affected in taurodontism.
Ans. Taurodontism commonly affects the multi-rooted permanent molars and sometimes the premolars. It is rarely seen in the primary dentition.
Q 198. Name some diseases which may be associated with taurodontism.
Ans. Down syndrome, Klinefelter syndrome, amelogenesis imperfecta and hypodontia.
Q 199. What is dens-in-dente?
Ans. Dens-in-dente is a common developmental anomaly of tooth characterized by a folding or invagination on the surface of the tooth towards the pulp.
Q 200. What is the other name of dens-in-dente?
Ans. Dens invaginatus.
Q 201. In dens-in-dente what is the typical appearance of the affected tooth?
Ans. Dens-in-dente produces a typical appearance called tooth-within-a-tooth.
Q 202. Name the tooth which is most commonly affected in dens-in-dente?
Ans. Maxillary lateral incisors.
Q 203. What are the types of dens-in-dente seen?
Ans. It can be mainly of two types: coronal type and radicular type.
Q 204. Describe the coronal type of dens-in-dente.
Ans. Coronal type of dens-in-dente occurs when the invagination or folding is seen in the crown portion of the tooth.
Q 205. What are the subtypes of coronal type of dens-in-dente?
Ans. The coronal type is further divided into three subtypes, which are as follows (Table 1.4):
Q 206. What is a radicular type of dens-in-dente?
Ans. In dens-in-dente if the invagination occurs in the root portion of the tooth it is called the radicular type and the condition presumably occurs due to folding of the Hertwig’s sheath during the development of root.
Q 207. What are the different clinical forms of dens-in-dente?
Ans. Depending upon the extent or depth of the invagination towards the pulp, dens-in-dente can be divided into three forms—mild, intermediate and extreme and these are mostly determined by radiographs.
Q 208. Describe the mild form of dens-in-dente.
Ans. The mild form of dens-in-dente exhibits a deeply invaginated or accentuated lingual pit area in the affected tooth.
Q 209. What is the intermediate form of dens-in-dente?
Ans. Intermediate form of dens-in-dente radiographically reveals a small, pear shaped invagination of the enamel and dentine into the pulp chamber; this produces a typical appearance of tooth-within-a tooth.
Q 210. Describe the extreme form of dens-in-dente.
Ans. In extreme form of dens-in-dente the invagination extends beyond the pulp chamber in the root of the affected tooth.
Q 211. What is a dilated odontome?
Ans. The extreme form of dens-in-dente is sometimes known as “dilated odontome”.
Q 212. What is the clinical significance of dens-in-dente?
Ans. In dens-in-dente the base of the pit or the deep invagination generally is composed of a thin and often defective layer of enamel and dentine, this makes the tooth extremely vulnerable to caries soon after the tooth erupts into the oral cavity. As a result most of the teeth with dens-in-dente frequently develop pulpitis, pulp necrosis, periapical cysts or periapical abscesses, etc.
Q 213. Define dens-evaginatus.
Ans. Dens-evaginatus is a rare developmental anomaly of tooth, in which a focal area of the crown projects outwards and gives rise to a “globe shaped” or “nipple shaped” protuberance on the occlusal surface.
Q 214. How does dens-evaginatus develop?
Ans. Dens-evaginatus probably develops as a result of excessive localized elongation and proliferation of the inner enamel epithelium as well as the odontogenic mesenchyme into the dental organ.
Q 215. Name the tooth which is most commonly affected in dens-evaginatus.
Ans. The condition primarily affects the premolars.
Q 216. What happens when deliberate cutting or grinding is done to the extra cusp or protuberance on the tooth in dens-evaginatus?
Ans. Since the extra cusp contains a vital pulp-horn, its deliberate cutting or grinding may result in pulp exposure with pain, pulpitis and the other associated symptoms.
Q 217. What is talon cusp? (talon means a claw, especially one belonging to a bird of prey).
Ans. Talon cusp is a developmental anomaly characterized by a projection from the lingual aspect of tooth that often resembles an eagle’s talon.
Q 218. Name the teeth in which talon cusps are commonly seen.
Ans. Maxillary and mandibular permanent incisors.
Q 219. How talon cusp clinically appears?
Ans. This abnormal cusp arises from the cingulum area of incisor teeth, which extends up to the incisal edge as a prominent T-shaped projection.
Q 220. What is enamel pearl (pearl means a hard, lustrous spherical mass, typically white or bluish-gray, formed within the shell of a pearl oyster)?
Ans. Enamel pearl is a white, dome shaped calcified projection of enamel, usually located at the furcation area of a molar tooth.
Q 221. Enamel pearls are commonly seen in relation to which tooth?
Ans. Maxillary molars are more frequently affected than any other teeth.
Q 222. What is enamel hypoplasia (hypo means less and plasia means formation)?
Ans. Quantitatively defective enamel having normal thickness is known as enamel hypoplasia.
Q 223. What is enamel hypocalcification?
Ans. Qualitatively defective enamel having normal thickness is called enamel hypocalcification.
Q 224. What are the causes of enamel hypoplasia.
Hypocalcemia (lack of calcium in blood)
Exanthematous disease (any disease with skin eruption and rash, e.g. measles)
Some types of epidermolysis bullosa
Q 224a. What is Turner’s tooth?
Ans. Hypoplastic tooth due to local infection or trauma is called Turner’s tooth.
Q 224b. Which teeth are most frequently affected by Turner’s hypoplasia?
Ans. Maxillary incisors.
Q 224c. Which vitamin deficiency can lead to enamel hypoplasia?
Ans. Vitamin A and D.
Q 224d. What kind of dental malformation can result from disturbance of growth in the first 6 months of life?
Ans. Enamel hypoplasia.
Q 225. What is the hereditary type of enamel hypoplasia?
Ans. Amelogenesis imperfecta.
Q 226. How focal enamel hypoplasia appears clinically?
Ans. Focal enamel hypoplasia clinically presents a white opaque spot on the smooth surface enamel.
Q 227. How generalized enamel hypoplasia clinically appears?
Ans. Generalized enamel hypoplasia clinically presents horizontal line of small pits or grooves on the enamel surface.
Q 227a. A generalized growth failure during the first year of life will have what type of impact on tooth enamel?
Ans. Enamel hypoplasia.
Q 228. What is mottling of enamel (mottling—a condition of spotting with patches of color)?
Ans. Mottling of enamel is a type of enamel hypoplasia which occurs as a result of damage to the ameloblast cells due to fluoride toxicity.
Q 229. How the mottled enamel clinically appears?
Ans. The affected tooth often has chalky or typical paper white opaque enamel with areas of flecking or pitting (Opaque means impenetrable by light; neither transparent nor translucent).
Q 230. Describe the effects of raised fluoride levels on enamel and bone.
Ans. The effects of raised fluoride levels are given in the Table 1.5.
Q 231. What is amelogenesis imperfecta (amelogenesis means process of formation of enamel of tooth)?
Ans. Amelogenesis imperfecta is a heterogenous group of hereditary disorders of enamel formation affecting both deciduous and the permanent dentition.
Q 232. Name the types of amelogenesis imperfecta.
Ans. There are four types of the disease which are as follows:
Type I: Hypoplastic type of amelogenesis imperfecta
Type II: Hypomaturation type of amelogenesis imperfecta
Type III: Hypocalcification type of amelogenesis imperfecta
Type IV: Hypomaturation-hypoplastic type with taurodontism.
Q 233. What is the characteristic feature of hypoplastic type of amelogenesis imperfecta?
Ans. There will be defective formation of enamel matrix.
Q 233a. How does the teeth appear in hypoplastic type of amelogenesis imperfecta?
Ans. The teeth exhibit either complete absence of enamel from the crown surface or there may be a very thin layer of enamel on some focal areas of the crown.
Q 234. What type of enamel is present in tooth in hypopcalcification type of amelogenesis imperfecta?
Ans. Enamel is soft and can be pierced or easily removed with the help of dental explorers.
Q 234a. Describe the appearance of teeth in hypomaturation type of amelogenesis imperfecta.
Ans. Here the enamel is of normal thickness but it does not have the normal hardness and translucency (snow-capped tooth). The enamel can be pierced with an explorer tip with firm pressure.
Q 235. How does the teeth appear in hypocalcification type of amelogenesis imperfecta?
Ans. In hypocalcification type of amelogenesis imperfecta the enamel is of normal thickness but is soft and can be easily removed with a blunt instrument.
Q 236. What is hypomaturation hypoplastic type with taurodontism?
Ans. This is a rare condition where taurodontism is reported in association with amelogenesis imperfecta.
Q 237. What are the chief clinical features of amelogenesis imperfecta?
Ans. Chalky discoloration of tooth, presence of thin, soft enamel on the tooth surface or no enamel at all severe abrasion of teeth, etc.
Q 237a. What is the usual color of teeth in amelogenesis imperfecta?
Ans. The teeth are often yellowish-brown in color.
Q 238. What is the snow-capped teeth?
Ans. In the mildest form of hypomaturation type of amelogenesis imperfecta, the enamel is of near normal hardness and the teeth exhibit some white opaque flecks at the incisal margins. These types of teeth are known as snow-capped teeth.
Q 239. Name some conditions in which malformation of crown of tooth is seen?
Peg-shaped laterals (the teeth whose sides converge or taper together incisally).
Environmental enamel hypoplasia
Fusion of tooth
Gemination of tooth
Vitamin-D resistant rickets
Radiotherapy during infancy.
Q 240. Define dentinogenesis imperfecta.
Ans. Dentinogenesis imperfecta is an inherited disorder of dentin formation, characterized by excessive formation of defective dentin; which results in obliteration of pulp chambers and root canals of tooth.
Q 241. What is the other name of dentinogenesis imperfecta?
Ans. Hereditary opalescent dentine (opalescent means resembling an opal in the display of various colors).
Q 241a. Dentinogenesis imperfecta occurs during which stage of tooth development?
Ans. During the stage of histodifferentiation.
Q 242. What are the types of dentinogenesis imperfecta?
Ans. Dentinogenesis imperfecta is of three types which are as follows:
Type I: Dentinogenesis imperfecta associated with osteogenesis imperfecta
Type II: Dentinogenesis imperfecta not associated with osteogenesis imperfecta
Type III: Dentinogenesis imperfecta Type III or Brandywine type.
Q 243. Describe the clinical appearance of dentinogenesis imperfecta.
Initially after eruption, the teeth appear amber-like but afterwards the teeth become either gray or yellowish-brown in color with a bluish reflection from the enamel
The teeth in dentinogenesis imperfecta often have tulip shape, which is characterized by a broad crown and a narrow constricted cervical area
The overlying enamel is structurally normal in most cases; however, this enamel is lost rapidly from the dentin surface soon after the teeth erupt in the oral cavity
Q 243a. What is the usual appearance of teeth in dentinogenesis imperfecta?
Ans. The teeth often appear translucent and yellowish-gray in color.
Q 243b. In dentinogenesis imperfecta, why there is early loss of enamel from the tooth surface?
Ans. Due to defect in the dentino-enamel (D-E) junction; D-E junction is normally scalloped but it is straight in this disease, causing poor locking between enamel and dentin.
Q 244. How type I and type II variants of dentinogenesis imperfecta differs from type III?
In type I and type II variants of dentinogenesis imperfecta there is excessive deposition of dentin with obliteration of pulp chambers
In type III there is little dentin formation in the tooth with large pulp chamber
Moreover the type III variant often exhibits multiple pulp exposures and periapical lesions in deciduous teeth.
Q 244a. Which type of dentinogenesis imperfecta shows multiple pulp exposures in deciduous teeth?
Ans. Dentinogenesis imperfecta type-III.
Q 245. What is ‘shell tooth’ (shell means a hard calcareous covering of an animal)?
Ans. In type III dentinogenesis imperfecta the affected tooth exhibits extremely large pulp chamber surrounded by a thin shell of dentine and enamel; this results in a classic appearance of the tooth which is called shell tooth.
Q 245a. Shell teeth are characteristically seen in which type of dentinogenesis imperfecta?
Ans. Type III dentinogenesis imperfecta.
Q 246. Describe the radiological features of type I and II dentinogenesis imperfecta.
Ans. The affected teeth have bulb-shaped or bell-shaped crowns with abnormally constricted cervical areas.
There will be varying degrees of obliteration of the coronal as well as the radicular pulp chamber (obliteration means completely concealing).
Q 247. Describe the radiological features of type III dentinogenesis imperfecta.
Ans. The affected tooth exhibits extremely large pulp chamber surrounded by a thin shell of dentine and enamel (shell tooth).
Q 248. What is the characteristic of dentino-enamel junction in a tooth with dentinogenesis imperfecta?
Ans. The dentino-enamel junction appears smooth or flattened instead of being scalloped as seen in a normal tooth.
Q 248a. Name another disease in which loss of scalloping of dentino-enamel junction is seen in the teeth.
Ans. Ehlers-Danlos syndrome.
Q 249. Name the diseases in which pulp of the teeth will be enlarged?
Dentinogenesis imperfecta type III
Vitamin D resistant rickets.
Q 249a. Name the conditions where obliteration of pulp chamber of the tooth often occurs.
Ans. The conditions are:
Dentinogenesis imperfecta type I
Dentinogenesis imperfecta type II
Dentin dysplasia type I.
Q 250. What is dentin dysplasia?
Ans. Dentin dysplasia is a hereditary disorder of tooth characterized by defective dentine formation and abnormal pulpal morphology with normal enamel.
Q 251. What are the types of dentin dysplasia?
Ans. The condition is classified into two types:
Type I or radicular dentin dysplasia
Type II or coronal dentin dysplasia.
Q 252. What is the other name of dentin dysplasia?
Ans. The condition is also known as root-less teeth.
Q 253. Describe the clinical features of type I (radicular) dentin dysplasia.
Ans. In this type the crown of the tooth is normal while the roots are extremely short and rudimentary; as a result the teeth often exfoliate prematurely.
Q 254. How does such tooth in type I dentin dysplasia appear radiographically?
Ans. Obliteration of pulp chamber is a common feature, there may be presence of unexplained periapical radiolucencies; mandibular teeth may have W shaped roots.
Q 255. Describe the histological features of type I dentin dysplasia.
Ans. Histologically, the mantle dentin appears normal and the remaining dentin often resembles what is called a series of sand dunes or lava flowing around boulders; moreover, remnants of pulp tissue may occasionally be seen between the normal and the abnormal dentin.
Q 256. What is the clinical appearance of tooth in dentin dysplasia type II (coronal type)?
Ans. Both deciduous and permanent teeth are affected by this disorder; the permanent teeth are of normal color; whereas the deciduous teeth exhibit an amber-gray color with some translucent or opalescent appearance.
Q 257. What is the radiological appearance of teeth in dentin dysplasia type II?
Ans. The deciduous teeth in dentin dysplasia type II reveals obliterated pulp chambers and root canals, thereby resembling dentinogenesis imperfecta and the permanent teeth exhibit large pulp chambers with a typical thistle tube appearance. Unlike dentinogenesis imperfecta there is no cervical constriction of the teeth in dentin dysplasia type-II.
Q 257a. Thistle tube appearance is present in which type of tooth anomaly?
Ans. It is seen in permanent teeth with the anomaly of dentin dysplasia type-II.
Q 257b. Name one important radiographic finding in coronal type dentin dysplasia.
Ans. Thistle tube appearance of pulp chamber in the affected tooth.
Q 258. What is regional odontodysplasia?
Ans. Regional odontodysplasia is an unique non-hereditary developmental disturbance of teeth; characterized by defective formation of enamel and dentin along with abnormal pulp.
Q 259. What is the other name of regional odontodysplasia?
Ans. Ghost tooth.
Q 260. What are the clinical features of regional odontodysplasia?
Ans. Several contagious teeth in the dental arch are affected at a time and the teeth are often deformed with soft leathery surface and are yellowish-brown in color. The affected teeth exhibit either delayed eruption or a complete failure of eruption.
Q 261. What is the radiological appearance of regional odontodysplasia?
Ans. There is marked decrease in the radio density of these teeth as a result of defective mineralization and because of this they often have a ghostly appearance. Moreover, the pulp chambers of such teeth are extremely large and open.
Q 261a. Which teeth are most often affected by regional odontodysplasia?
Ans. Maxillary permanent central incisors.
Q 262. Describe in brief the histological appearance of regional odontodysplasia.
Ans. The enamel layer is attenuated and disrupted, the dentin is very thin and globular with irregular tubules and a wide predentine layer. Large pulp chamber exhibits numerous pulpal calcifications.
Q 263. Name the diseases associated with malformation of roots of teeth.
Dentin dysplasia type-I
External resorption of tooth.
Q 264. What is hypercementosis?
Ans. Hypercementosis is the increased, abnormal thickness of cementum of teeth which results from abnormal cementogenesis.
Q 265. Enumerate the causes of hypercementosis.
Paget’s disease of bone
Q 266. What is hypocementosis?
Ans. Hypocemtosis or acementosis is a rare developmental anomaly of tooth characterized by lack of cementum formation.
Q 267. Name the diseases associated with hypocementosis of teeth.