Not all patients are good candidates for dental implants, even if the clinical situation seems to be a good indication. Evaluation of dental history allows the clinician to establish a comprehensive treatment plan and to prevent the risk of failure or complication. Information is provided by the patient during initial interviews.

Compliance

Before surgery, during wound healing and after prosthesis delivery, a minimum of patient cooperation is essential to prevent complications. Some patients refuse to participate actively in their treatment, and their excessive “passivity” may be a barrier to the development of an implant treatment plan. Early detection of these “unmotivated” patients avoids unnecessary inconvenience for the clinician and the patient.

Oral Hygiene

Effective dental plaque control is a prerequisite for successful implant therapy. A detailed description of patient brushing techniques and the type of professional support therapy must be reviewed, to be corrected if necessary. This point is particularly important for edentulous patients who no longer maintain effective plaque control habits.

Inadequate plaque control has a significant impact on:

• early implant failure in partially edentulous patients (bacterial contamination during surgery) (van Steenberghe et al., 1990)
• excessive bone loss around osseointegrated implants, even in edentulous patients
• peri-implantitis (see Chapter 50).

Bruxism

Although this is a controversial issue, the trend is that excessive occlusal loading increases the risk of mechanical complications (prefabricated component), technical complications (laboratory fabricated) and failures (Salvi & Bragger, 2009). Despite this, bruxism (except in extreme cases) is not a contraindication for dental implants, but precautions are recommended for the selection of implants and elaboration of the restoration design.

History of Tooth Loss

Origin of tooth loss must be stated as it can compromise implant success or complicate dental implant placement.

Endodontic infection/