Complications and Prognosis
The survival of implants in suitably selected patients is generally very high.
Implants however do fail and can be lost for a variety of reasons.
Scientific evidence suggests that the longevity of implants may not be superior to that of a diseased but well-restored natural dentition.
A key factor for long-term implant survival is the quality of periodontal and implant maintenance.
Dental implant complications can be divided into two types:
► See also: DENTAL ANESTHESIA : Mandibular Anesthesia : Gow-Gates technique
a) Early complications
b) Late complications
Early implant failures usually arise from failure of the initial integration to take place during the biological healing phase.
Poor surgical technique, inability to achieve primary fixation, inadvertent implant loading during the integration phase, infection and systemic conditions such as uncontrolled diabetes are some of the factors that could cause early implant loss.
Late failures are caused by one or both of the following two fundamental reasons:
a) Biological failures: caused by plaque-induced peri-implant disease. If untreated, the progressive crestal bone loss results in implant mobility.
b) Mechanical failures: caused by unfavourable loading conditions due to poor restorative design or failure to control occlusal interferences.
Typically, mechanical failures are manifested by screw or abutment loosening or porcelain fractures.
Implant fractures have also been reported but these tend to occur in reduced diameter implants.
Early failures are difficult to predict, measure or prevent. Late failures, on the other hand, can be identified and treated successfully if they are intercepted in the early stages of the disease process.
In this respect, any clinician who accepts an implant patient for maintenance assumes significant responsibilities and duty of care for monitoring dental implants and the health of the peri-implant soft tissues. This requires a systematic recall programme of monitoring and maintenance.
Recent surveys have shown that there appears to be contradictory advice on how best to monitor and maintain dental implants in function. This is surprising as the periimplant disease is being shown to be common with an incidence rate ranging from 5% to 56%.
Given that the current market is approximately 130,000 implants per year in the UK, this represents a large number of patients who might be affected by peri-implant disease annually.
Evidently, the importance of a strategic approach to implant monitoring and maintenance is clear; this can be divided into the following areas:
• Reduction of risk factors
• Patient education and motivation
• Screening and surveillance
• Instrumentation and intervention
Association of dental implantology