226 Theories and techniques of oral implantology

—except the first, which is purely anatomic—should be eliminated.

For arthropathogenic anatomic variants, or arthrosis, there is unfortunately very little specific therapy other than giving the patient a better insight into his problem, trying to induce better chewing habits, and encouraging him to accept the situation. Sometimes surgery is necessary in those situations where, for example, arthritic degeneration of the disk or joint renders it almost impossible for the functioning of the jaw.

For traumatic arthritis, diskitis, retrodiskal pad injury, ankylosis, and capsulitis, corticosteroid therapy usually reduces the symptoms. Various other treatments for the elimination or reduction of ternporomandibular joint disorders are available, such as intracapsular and supracapsular injections with local anesthetics, adrenocorticals, sodium psylliate, and hyaluronidase. Occlusal splints, as well as devices to restrain mouth opening, also can be constructed to eliminate or reduce temporomandibular joint disturbances.

No matter what procedures are used, however, it should be remembered that joints need a consider-able time for recovery, and an implant procedure must be delayed until the patient can move his jaw freely and without pain.

Muscle patterns

Paralysis of the motor root of the fifth nerve inhibits the action of the pterygoid muscle. As a result, there is a deviation of the midline in mouth opening and consequent occlusal problems. Because the paralysis is usually permanent, implants might have to be contraindicated.

Thumb- and finger-sucking, tongue-thrusting and lip-biting, mentalis muscle habits, mouth-breathing, and other poor oral habits resulting in abnormal muscle patterns may produce shifting of the teeth, thereby producing a malocclusion pattern more or less characteristic of the habit. In this manner, muscular imbalances contribute to the general etiology of acquired malocclusion and could contraindicate the use of implants.

High muscular attachments, interfering frenums, scar tissue, and other conditions can cause excessive muscular pull in abnormal directions. This may influence gingival recession around an implant or create an abnormal pull in the area, causing excessive pressure on the bone supporting the implant. Therefore the operator must look for such situations and eliminate them with corrective surgical inter

vention. In this way he can eliminate or reduce a problem that could otherwise lead to implant failure caused by increased pocket formation and bone re-sorption.

Sinusitis

Some presenting candidates are prone to sinus conditions that may contraindicate implants in the maxillae. Sinusitis is usually caused by colds or coughs that secondarily infect the sinuses. When the maxillary sinus becomes inflamed, the infection may spread to the implant site and infect both the connective tissue around the implant and the surrounding bone. This is one reason why it is essential to avoid approaching too closely or penetrating a maxillary sinus, even in a nonsinusitis-prone patient. Typically, a sinus becomes inflamed from the internal spread of an infection, but infection may also spread to a sinus from a poorly placed implant.

Cleft palate

Cleft palate is characterized by a fissure of the palate and roof of the mouth. The upper lip has a small nick in the vermilion border that completes the cleft. Depending upon the degree of malocclusion, it is possible to use implants. In fact, implants with specially designed supports across the palate seem quite promising in some cases.

EVALUATING SYSTEMIC DISORDERS

Systemic disorders are frequently reflected in the mouth and its associated structures. Recognizing the clinical symptoms of various disorders is a must for the dentist, who would be well advised to refer the patient to a medical doctor. If the disorder is treat-able or at least controllable, the implant candidate may then return to the dentist. At that point, the dentist, working closely with the medical doctor, can reevaluate the candidate.

Heart diseases and circulatory disorders

The leading cause of death today in the United States is disorders of the heart and circulatory system. Most of these conditions appear during middle to late life, and undoubtedly many presenting patients will have some form of heart or circulatory disorder. No matter how minor the patient says his condition is, it is always a good idea to consult his physician for a true picture of the disorder to help determine the type of anesthetic to be used and to discuss the nature of the patient's drug therapy.

Arteriosclerosis. Arteriosclerosis, or hardening of