History Taking and Clinical ExaminationCHAPTER 1

If properly and thoroughly performed, medical history and physical examination are the best diagnostic aids to arrive at a specific diagnosis. Without a comprehensive history and a properly performed examination of the patient, the clinician would be just a hit-or-miss technician. For a clinician to be successful in the diagnostic procedure, there has to be an integration of subject knowledge, experience, intuition, and common sense. It must also be emphasized that learning process in never complete. Throughout life, acquiring knowledge remains as a continuum of events and the clinician must keep himself acquainted with the latest information and results of research.

A new concept that finds wider application even in dentistry is something called as evidence-based dental practice. Evidence-based dentistry is a method for rapidly aggregating, distilling, and implementing the best evidence in clinical practice (according to Sackett et al., 1996 and Straus et al., 2005). Practice of evidence-based 2dentistry involves the best clinical evidence and clinical judgment together with patient values and circumstances, to improve healthcare.

As a subject area, oral medicine is relatively new. The history of evolution of oral medicine is also not precise. The reason for this may be the overlap of various spheres of medical and dental sciences in oral medicine. The efforts and investigations of many scientists have helped in the emergence of oral medicine as a discipline in the dental curriculum. When we go through dental history, we can find out that Thomas E Bond (Fig. 1-1) can be considered as the father of oral medicine. He was the first person to have authored a book on maxillofacial pathology.

According to the British Society of Oral Medicine, Sir Jonathan Hutchinson (1828–1900) (Fig. 1-2), surgeon to the London Hospital, can probably be regarded as the father of oral medicine and encompassed oral medicine as practiced in the totality of medicine. He is particularly well known for describing ‘Hutchinson's interstitial triad’ seen in congenital syphilis, i.e., ‘interstitial keratitis, notched incisor teeth and deafness.

In the 19th century, oral mucosal disease was only really detailed in textbooks of dermatology and it was not until 1948 when Hubert Stones, of the University of Liverpool, published his book entitled Oral and Dental Disease that the general medical aspects of oral disease were emphasized.

In the 1950s, an interest in oral medicine was shared by those who already had clinical expertise and a research interest in oral surgery and oral pathology. However, it was the Nuffield Foundation's decision to fund the first two Chairs in oral medicine that was pivotal in the establishment of the specialty. Martin Boyes filled one of these chairs in oral medicine at Newcastle University and Martin Rushton filled a chair in dental medicine at Guy's Hospital. The Nuffield Foundation also funded scholarships and fellowships, which were subsequently awarded to many of those individuals who were attracted to the new discipline of oral medicine throughout the 1950s and 60s.

The Eastman Dental Hospital had already become the Postgraduate Dental Institution (1948) and has, since then, played a significant role in the delivery of postgraduate courses in oral medicine for trainees from both the UK and overseas.

In Wales, Brian Cooke established his oral medicine unit in Cardiff and, in Scotland, David Mason headed the Department of Oral Medicine and Pathology in Glasgow.

David Mason also founded, along with Dean Millard of the University of Michigan, the prestigious series of world workshops in oral medicine which continue to flourish.

As diagnostic investigations involving immunopathology, hematology, biochemistry, and imaging improved, together with advances in therapeutic interventions, such as corticosteroids, it became apparent that oral medicine was gradually separating from oral pathology. It was also increasingly challenging for individuals to maintain the knowledge and expertise required to encompass both disciplines.

In the 1990s and the beginning of the 21st century there were, however, a diminishing number of oral pathologists who were also practicing clinical oral medicine. Another factor which separated the two disciplines was the fact that oral medicine was originally linked with oral surgery in training overseen by the Royal College of Surgeons, whereas the training program in oral pathology was under the auspices of the Royal College of Pathologists.

Diagnosis essentially forms the basis for therapy. Without properly diagnosing the disease process of the patient, treatment will be ineffective. In many of the clinical situations, it may be possible to arrive at a diagnosis just by listening to the history and performing a thorough physical examination. However, in other instances, routine or even specialized laboratory procedures may be necessary to arrive at a diagnosis.

Diagnosing an oral lesion may at times prove difficult because of the multiplicity of oral diseases and also due to the similarity of several of the lesions. Some of the oral diseases have typical clinical appearance and it would be very easy to diagnose them.

One of the greatest advantages in diagnosing oral lesions is that, direct visualization of oral cavity is possible. Ready access of various structures in the oral cavity also makes it easy to perform any examination procedures.

In the present day as many branches of dentistry have distinct advantages of facilitating performance of treatment procedures, the importance of oral medicine as a subject area has been sidelined. The general belief is that it merely acts as a screening department which directs the patients to other departments for procedures. This thought has to be changed because diagnosing oral diseases is important on the one side and a significant number of patients are also being treated in the department, especially for oral mucosal lesions. Essentially, oral medicine is equivalent to the general medicine of a medical institution.

Most of the oral diseases are primarily of local origin, originating within the oral region due to a local cause. However, it must be emphasized that there are many oral diseases that have a systemic origin. In some cases, treating the systemic problem is also important for the management of the oral problem.4

Recording patient's history is an important step in the diagnostic process. Many clinicians feel that the time spent for recording the case history is a waste. However, it must be emphasized that recording the patient's history is of paramount importance in the clinical practice because this would help in the identification of any underlying medical problems of the patient which may have an implication in the dental treatment. It must be borne in mind that the time spent for recording the case history is not a waste, rather it is a systematic approach in the effective patient management process. History also includes the following:

Nowadays, many clinicians attribute more importance to the laboratory investigations than the physical examination of the patient. This is not a correct method of clinical practice. While performing a thorough physical examination, vital information about the physical condition of the patient and the nature of the disease process will be known to the patient. By performing only a cursory physical examination, too much emphasis must not be given to the laboratory investigations alone.

The role of laboratory studies is to confirm or rule out a tentative diagnosis. In many situations, vital information are available while performing a physical examination. However, to confirm it and to institute appropriate therapy, laboratory investigations may be necessary. Investigations can be anything from routine examination of blood pressure of the patient, radiographic examination, blood glucose determination, aspiration, or biopsy procedures.

It must be borne in mind that when the diagnosis is easily arrived at, unnecessary and complicated investigations must never be advised. Simple investigations must be carried out before embarking up on complicated and more expensive investigations.

The basis for modern therapy is diagnosis. It must be emphasized that both history taking and physical examination play important roles in identifying the disease process. Physical examination should always follow a properly taken case history.

In case of certain medical problems, the prognosis of an ideal dental treatment may not be quite satisfactory. Therefore, medical risk assessment of the dental patient also alters the treatment plan.

The following is an outline of a structured case history.

It would be helpful if the patient is addressed in his/her name so as to gain the confidence of the patient. Many of the patients reporting for dental procedures would be anxious and apprehensive. Addressing the patient in his/her name greatly helps in gaining the confidence of the patient. It will have a familiarity as well as calming effect of the patient.

It has been proven that whenever a patient presents with a complaint such as pain, there is also an emotional component to it apart from the organic basis of the complaint. Addressing the patient in his/her name and a compassionate attitude from the part of the clinician would go a long way in the success of a dentist-doctor relationship.

Recording of the identification data or routine data of the patient consist of the following informations:

Chief complaint is recorded in the patient's own words and in chronological order if the 6patient has more than one complaints. Also, it should be emphasized that the chief complaint must be recorded in a complaint form and not suggesting the treatment. For example, it should be never recorded that patient requires cleaning.

The following are the salient points to be remembered while recording the patient's chief complaint:

If a patient is properly informed about the significance of the medical problems, he/she would be happy to disclose any of their medical problems and he/she would appreciate the care and concern the dentist exhibits in identifying the medical problems of his/her patient.

The patient who presents for dental treatment should be specifically asked about the following medical conditions which have relevance in the dental treatment:

Some patients who report to the clinician may have cancerophobia (fear of having cancer), if any of their relatives might have suffered from oral cancer. Convincing these patients is a very difficult exercise. Many patients would demand even biopsy procedure to be performed on them, even without any lesion present in their oral cavity.7

General examination (the first three components of general examination) may be carried out as the patient is entering the operatory or as the patient is walking towards the dental chair. The last four entities are collectively called as the vital signs.

General examination also includes examination of specific anatomic regions as outlined below after the discussion of vital signs.

Normal oral temperature is 98.4°F or 37°C. Axillary temperature is 0.5° lower and rectal temperature is 1° higher. Fluctuation in the temperature is associated with meals, hot bath, etc. Evening temperature is 1°F higher than the morning temperature.

Hypothermia or drop in the temperature (a temperature below 35°C) occurs where the mechanisms to create heat production are ineffective. Temperatures below 35°C, or a trend to decrease towards this level is considered abnormal.

Temperature drops in the following conditions:

Elevation of temperature (pyrexia) is suggestive of febrile illness or infection. Temperatures above 37.4°C, or a trend of temperature increase towards and above this level warrants attention.

Hyperthermia (a temperature above 37.5°C) occurs as a result of a resetting of the temperature set point caused by the release of pyrogens from certain cells, usually as a result of cellular ingestion of bacteria. Other causes may include the following:

Any variation in the temperature produces a physiological response to bring it back to a set point (around 37°C). The center for controlling the temperature is in the hypothalamus of the brain.

Recent ingestion of food, high respiratory rates, and smoking may all affect the oral temperature.

The role of oxygen flow in producing cold gas currents has also been investigated as a factor in causing erroneous data and should be considered if erroneous results or results that are inconsistent with the patient's other clinical assessment data occur. As with all clinical assessment data, measured values should be viewed as part of a trend or fluctuation from baseline values.

While checking for the pulse, the fleshy portions of the index and middle fingers must be gently pressed on the arteries. The thumb should never be used for checking the pulse as the thumb contains its own artery which pulsates. In a child, always the brachial artery in the upper arm should be used.

Normal pulse rate is 72 per minute. It is rapid in children. In the newborn babies it is about 140 per minute. In older individuals the pulse rate may be 55–65 per minute. Tachycardia is seen after exercise, fever, thyrotoxicosis, emotional upsets etc.

Blood pressure increases as age advances and 150/90 mmHg is considered as the upper limit. Blood pressure is elevated in the following conditions:

Both the systolic and diastolic pressure measurements are important—if either one is raised, it means that the blood pressure is high.

To take a blood pressure reading, the patient must be relaxed and comfortably seated, with the arm well supported. Alternatively, the patient can lie on an examination couch.

The blood pressure can be measured by a sphygmomanometer [blood pressure (BP) apparatus)] or electronically using electronic BP apparatus.

When we breathe more than the medically accepted norm, CO₂ is lost and it reduces the body oxygenation due to vasoconstriction and the suppressed Bohr effect caused by hypocapnia (CO₂ deficiency). Hence, overbreathing leads 11to reduced cell oxygenation, while slower and easier breathing (with lower respiratory rates) improves cell oxygen content.

Medical research suggests that the respiratory rate is the marker of pulmonary dysfunction that gets progressively worse with advance of a large number of chronic health conditions.

Determination of the pulse must be made surreptitiously while the pulse is being recorded. Normal respiratory rate is 16–20 per minute. In children it is faster and in adults it is slower.

Respiratory rate is increased in the following conditions:

Palpate directly over the joint when the patient opens and closes the mandible, and the extent of mandibular condylar movement can be assessed. Normally, condylar movement is easily felt. Have the patient close slowly, and the condyle moves posteriorly against the palpating finger. Tenderness elicited by this maneuver is invariably associated with articular inflammation. The joint is auscultated during mandibular motion. The normal joint functions relatively quietly. Listen for crepitus or grinding and clicking or popping sounds.

The degree of mandibular opening is measured using the distance between the incisal edges of upper and lower anterior teeth. Opening of less than 35 mm is considered abnormal in an adult. There is no upper limit of normal, but few patients can exceed 60 mm comfortably. Observe the opening pattern for deviation. The mandible often deviates toward the affected side 12during opening because of muscle spasm or mechanical locking by a displaced meniscus.

Mandibular opening is initiated by action of the suprahyoid muscles. Simple rotation of the mandibular condyle in the glenoid fossa accounts for the first 25 mm of interincisal opening. Further opening is due to a forward gliding or translation of the condyle along the posterior slope of the articular eminence. Forward motion of the condyle is guided by action of the lateral pterygoid muscle. Mandibular closure is due to action of the temporalis, masseter and medial pterygoid muscles.

The masticatory muscles are the masseter, temporalis, medial pterygoid, and lateral pterygoid. Apart from these muscles, there are accessory muscles. These are the suprahyoid muscles, such as digastrics, stylohyoid, mylohyoid, and geniohyoid and infrahyoid muscles, such as sternohyoid, thyrohyoid, and omohyoid.

The masseter muscle extends from the zygomatic arch to the ramus and body of the mandible. The fibers of this muscle are broad, extending from the region of the second molar on the surface of the mandible to the surface of the ramus. It has two parts, superficial and deep. Its origin (superficial layer—anterior 2/3^rd of lower border of zygomatic arch and zygomatic process of maxilla, middle layer—anterior 2/3^rd of deep surface and posterior 1/3^rd of lower border of zygomatic arch and deep layer—deep surface of zygomatic arch) and insertion (superficial layer—lower part of lateral surface of ramus of mandible, middle layer—middle part of ramus and deep layer—upper part of the ramus and coronoid process) make it very useful for the movement of the jaw and for applying good bite force for mastication. Masseter muscle is a powerful muscle because of its multipennate arrangement of fibers.

The main functions of masseter muscle are elevation of the mandible, lateral movements of the mandible for efficient chewing and grinding of the food, unilateral chewing movements, and retraction of the mandible. Masseter muscle can be palpated both intraorally and extraorally. It is the most common muscle involved in myositis ossificans. The muscle that commonly undergoes hypertrophy in bruxism is the masseter. Masseter muscle is palpated over the ramus of the mandible by asking the patient to clench the teeth.

The functions of temporalis muscle are elevation of the mandible, retraction of the mandible, and crushing of food between the molars. Posterior fibers draw the mandible backwards after it has been protruded. It is also a contributor to lateral grinding movement.

Sudden contraction of temporalis muscle will result in coronoid fracture, which is rare. Temporalis muscle is palpated over the temporal facia region of the forehead.

The functions of lateral pterygoid muscles are to depresses the mandible, protrude it forward for opening of the jaw and lateral movements. It is the most commonly involved muscle in myofascial pain dysfunction syndrome (MPDS). 13It is also the only muscle of mastication which is attached to the TMJ. Lateral pterygoid forms the roof of the pterygomandibular space. Direct palpation of lateral pterygoid muscle is not possible. However, indirect palpation is possible by running and pressing the palpating finger over the maxillary tuberosity region.

The functions of this muscle are elevation of the mandible, closing of the mandible and side to side movement. Medial pterygoid muscle can be palpated only intraorally. It is also involved in MPDS.

Trismus following inferior alveolar nerve block is mostly due to involvement of medial pterygoid muscle.

Medial pterygoid muscle is palpated by running the palpating finger along the medial aspect of the mandible.

Provisional diagnosis requires confirmation by suitable laboratory or diagnostic procedures or any other investigation. It has to be remembered that while recording provisional diagnosis, only the relevant probabilities must be considered.

Once the results of all the investigations are available, the history, physical examination findings, and the results of laboratory or other investigation results must be logically and systematically analyzed and appraised in order to arrive at the final diagnosis which forms the sound basis for treatment.

In certain situations, there may be a delay for the laboratory investigations to be made available. In such situations, empirical treatment may have to be instituted before the final diagnosis is reached.

Differential diagnosis refers to listing of more than one probable diagnoses which may have similar clinical course, symptoms, presentation or appearance and further investigations are necessary for confirming the condition or disease. The fact should be emphasized that the differential diagnosis should not include irrelevant assumptions which do not have even a remote resemblance to the condition that the patient presents with.

The differential diagnosis must be recorded on a priority basis with the most probable diagnosis listed first followed by the other probabilities. In many of the clinical situations, there will be only one clear-cut diagnosis and basically the treatment plan should be based on this conclusion and without any investigative procedures.14

The laboratory investigations should be pertinent and specific to the problem and absolutely essential for confirming the diagnosis. However, in certain situations, laboratory investigations are warranted in ruling out a suspected problem. The most commonly performed medical laboratory investigations are the following:

In many clinical situations, there may be requirement of various imaging techniques for arriving at definitive diagnosis. Various imaging techniques used in the dental practice are the following:

Biopsies also form part of the investigations. Biopsy refers to removal and examination of a part or whole of a lesion. The following are the various biopsy procedures:

The following are the precautions to be taken while performing surgical biopsy:

The frozen section technique is helpful to allow a stained slide to be evaluated within 10 minutes of taking the biopsy. This technique is usually performed when the patient is in the operating table. It must be emphasized that frozen sections are used only if the quickness of the result would make an immediate difference to the ongoing surgical procedure.

Fine needle aspiration cytology is employed in evaluating deep-seated lesions; e.g., in the evaluation of major salivary glands or lymph nodes.

Aspiration biopsy using wide bore needle is usually employed to evaluate; e.g., contents of a cystic lesion from the jaws.15

Oral exfoliative cytology refers to examination of cells obtained from the surface of a lesion. The advantages of oral exfoliative cytology are the following:

In spite of the above mentioned advantages, the technique may not be very reliable as false positive and negative test results can occur.

There may be a shift from the tentative diagnosis after the laboratory studies. This conflict is acceptable and should not be viewed as a mistake or flaw in the diagnostic process.

It is again of importance that the final diagnosis should be related to the chief complaint. However, if the clinician detects any other objective signs of disease, he can mention them and list them as subsequent diagnoses. Accordingly, mention must be made in the treatment plan.

The treatment plan must be made only after arriving at a definitive diagnosis. While planning the treatment, the patient must be properly informed and his/her consent must be obtained.

While treating a child patient, it is imperative that the child's parents are informed about the treatment plan and their consent must be obtained.

Similarly while treating mentally retarded patients or patients with communication problems or senile patients, the consent of accompanying people must be obtained after detailing to them the proposed treatment plan.

Unsatisfactory response to therapy requires a critical appraisal of the drugs prescribed and after a rethinking administration of substitution of other drugs should be considered.

It goes without saying that the patient must be specifically asked about any allergy to the drugs in the past. Again it must be emphasized that the patient's medical condition must be kept in mind while prescribing any drug so that the drugs prescribed are not a contraindication for the patient's medical condition.

While assessing the prognosis, the condition of the patient including his physical and medical condition or the general physical condition, the treatment outcome and the patient compliance 16parameters must be subjected to a critical appraisal.

It is of importance that false information about his overall well-being should never be given to the patient. Often giving false promise or hope to the patient can lead to the loss of reputation of the clinician.

While performing inspection, the objective signs of disease process become obvious to the clinician which may be correlated with the symptoms that have already been communicated to the clinician by the patient.

Palpation may be unilateral or bilateral and bimanual (using both the hands) or bidigital (using two fingers).

While performing palpation, the hands must be warm. It is also said that palpation must feel as if the patient is being caressed.

Aspiration is mainly performed in certain clinical situations when the lesion may contain a fluid content. For example, in case of cysts or any swellings. Aspiration would reveal the nature of the content of a pathologic process.

In the detection of dental caries, the explorer must be sharp. A bent or distorted explorer may not yield good result. In order to determine the pocket depth, the probe or explorer is walked along the gingival crevice to evaluate the depth of the pocket.

Graduated periodontal probes are available in the market in order to measure the pocket depth.