SECTION I | EXTRAORAL EXAMINATION: NORMAL STRUCTURES |
The first thing to notice during an initial meeting with a patient is his or her general appearance. You can obtain clues regarding possible health problems that have not yet been diagnosed, and you can begin to predict how well the patient will tolerate dental treatment. Notice the posture, gait, breathing, and general well-being during your greeting.
A close look at the head may reveal asymmetry of the head or a discrepancy in the relationship of the upper and lower jawbones. This could be important to identify swelling that could be a sign of pathology or infection and when determining how to identify and treat problems with the occlusion.
C. SKIN AND UNDERLYING MUSCLES OF MASTICATION
Observe the skin for any unusual lesions and describe each lesion by location (relative to adjacent normal landmarks), size, and the person’s knowledge of its history. The evaluator’s knowledge of pathology is necessary when distinguishing benign lesions from those requiring follow-up pathology consult and/or biopsy.
Muscles of the head and neck may be palpated to identify pain or tenderness that could be related to problems with the temporomandibular joint or an imbalance in the occlusion of the teeth (made worse when the person habitually clenches or squeezes the teeth together). For this reason, it is important to be able to locate and palpate these muscles where possible. You can palpate each muscle pair bilaterally by lightly massaging an area with the middle finger of each hand while using the index and fourth finger to palpate surrounding soft tissue to feel for unusual lumps or tenderness. Palpate these muscles on a partner while using Figure 15-1 as a guide.
- Masseter: Feel the body of the masseter by palpating the bulge over the lateral surface of the mandible near the angle while your partner clenches the jaws together. Move your finger down toward the angle of the mandible to feel the insertion (labeled No. 4 on Fig. 15-1), and move up toward the zygomatic arch (inferior border of the zygomatic bone and zygomatic process of the temporal bone) to feel the origin (labeled No. 3).
- Medial pterygoid: Feel the bulge when your partner clenches while palpating the medial surface of the angle of the mandible at the insertion (labeled No. 7). It may help to have your partner lean the head forward to relax the skin of the neck as you gently palpate upward and outward against the medial surface of the mandible near the angle, using the tips of your middle finger and forefinger. This may cause some discomfort.
- Temporalis, anterior fibers: Palpate the origin of the anterior (vertical) fibers on the forehead just above a line between the eyebrow and superior border of the ear (labeled No. 5). Since these muscle fibers help close the mouth, see if you feel the bulge when your partner clenches the teeth.
- Temporalis, posterior fibers: Palpate the origin of the posterior (horizontal) fibers of the temporalis just above and posterior to the superior border of the ear (labeled No. 6). Since these muscle fibers are involved in retruding the mandible, see if you can feel a bulge when your partner retrudes (pulls back) the mandible.
- Lateral pterygoid (intraoral palpation): The lateral pterygoid can only be palpated intraorally. Feel this muscle by placing your little finger in the vestibule of the mouth behind the maxillary tuberosity (labeled No. 8). (Use a skull to see how to reach the lateral plate of the pterygoid process of the sphenoid bone.) With your partner’s mouth slightly open and the mandible moved slightly toward the side being palpated, slide your little finger back toward the lateral pterygoid plate for the origin of the lateral pterygoid muscle. This may be uncomfortable to a patient even if the muscle is not sore. The anterior surface of the neck of the condyloid process is the location of part of the insertion of this muscle, but it cannot be palpated.