202 Theories and techniques of oral implantology

local pathologic disorders and abnormal patterns. The effects on them of disturbances elsewhere in the body will be covered in Evaluating Systemic Disorders, beginning on p. 226.

Examining the teeth and supporting bone

Any remaining teeth will be directly or indirectly involved in an implant restoration. Those teeth bordering the edentulous area will be used as natural tooth abutments for firmly securing the prosthesis. The other teeth should be in good occlusion and good condition, for overall poor occlusion can traumatize the implant restoration and eventually cause its failure.

The dentist must attend all caries, scale and clean the teeth, and check the bone investing the teeth for existing root tips. If necessary, apicoectomies or hemisections of the roots on those teeth that are to be retained as abutments should be performed. Also, teeth that cannot be preserved because of advanced disease should be extracted.

As part of his examination, the dentist should

radiograph both dental arches for troublesome conditions. He should test the vitality of the teeth with a pulp tester, hot and cold water, air blasts, the "cavity test," and hot gutta-percha. The degree of parallelism of all remaining crowns and the condition of tooth contact relationships should be examined, as well as the degree of traumatic occlusion that may exist from the shifting of remaining teeth. The amount of calculus and debris around the necks of all remaining teeth will give the dentist an idea of the patient's oral hygiene. Dental erosion, which is usually accompanied by increased sensitivity, should be considered. If eroded teeth are to be used as abutments, restorations over them may stop the wear.

The teeth should be closely examined for "wear facets," possibly indicative of occlusal habits—such as bruxism, clenching, and clamping—and percussive habits. If the evidence is indicative, the patient can be questioned again regarding oral habits that might very well contraindicate the introduction of implants.

Fig. 6-1. Sample questionnaire.