Background

Implant placement into the posterior maxilla often requires sinus augmentation. Whilst the sinus lift concept is well established, there are numerous variations on this technique. Procedures may be performed via a lateral (open) or transalveolar (closed) approaches with autogenous or non-autogenous graft material. Implants may be placed simultaneously or delayed. Sinus lifting is a vital component of an implant training program.

Objectives

To examine the success rates of implants placed into augmented maxillary sinuses within a training institution.

To identify factors related to failure of implants placed into augmented maxillary sinuses.

Methods

A retrospective review of all implants placed into augmented sinuses within a 7 year period at the Royal Dental Hospital of Melbourne was carried out. Implants were placed by trainees with different levels of experience under supervision. Inclusion criteria included minimum of follow-up of 3 months. Implant success was defined by the criteria suggested by Buser 1990. Descriptive statistics and Kaplan Meier survival analysis were performed to identify factors associated with implant failure.

Results

57 implants were placed into 37 patients. There were 5 failures, with an overall implant success rate of 91.2%.   There were no major medical co-morbidities and the rates of smoking and diabetes were 22% and 16% respectively.  Mean time of follow-up was 30 months. 41 implants were placed into autogenous grafts. 37 implants were placed simultaneously at the time of sinus augmentation.

Discussion

Overall success rates were high and comparable with other rates reported in the literature. Factors associated with an increased risk of failure were associated with simultaneous implant placement at the time of grafting and smoking. These results are consistent with previous reports and should influence patient selection and counselling regarding risk factors.  

In conclusion, high rates of implant success can be achieved in an implant training program.