Marginal bone loss around implants supporting fixed restorations.

A key criterion of success following dental implants is the marginal bone level. Long-term clinical and radiographic evaluation is necessary to test the results of in vitro studies investigating how cantilevering of restorations or implant size affect bone level changes around implants. There is no consensus on the effect of several variables such as age, gender, implant size, and cantilever prostheses on marginal bone levels around fixed dentures supported by dental implants. Patients who received cemented, fixed restorations supported by implants and who were examined in routine recall sessions 6, 12, 24, and 36 months after loading were included in the study group. Comparative bone level measurements were obtained from images of radiographs at ×20 magnification using the CorelDraw 11.0 software program. Statistical analysis was performed using the Student t test and 1-way analysis of variance. In the 36-month observation period, there were no incidences of implant failure, excessive bone loss around implants, or peri-implant inflammation. One hundred twenty-six implants in 36 patients were evaluated, and the effect of several factors on marginal bone loss (MBL) during the 36 months after loading was analyzed statistically. There was no significant relationship between MBL and implant length or diameter, whereas age, gender, and cantilevers affected bone loss rates. MBL was elevated in older and female patients as well as in patients who received cantilevers. In cases of limiting anatomic conditions, short and/or narrow implants should be preferred over cantilever extensions.