Clinical Outcomes of Single Implant Supported Versus Implant Supported-Fixed Prostheses in Dubai Health Authority Clinic
Whether implant-supported fixed prostheses have worse clinical outcomes than single implant-supported prostheses is controversial. This study aimed to assess the clinical outcomes of single implant-supported prostheses and implant-supported fixed prostheses placed in Al Badaa Dental Center in Dubai Health Authority (DHA). This retrospective study compared biological and technical complications among single implant-supported prostheses and implant-supported fixed prostheses in a time framed sample of all patients who received dental implants between January 2009 and December 2016. Cantilevered implants, implants supporting complete dentures or removal partial dentures and any case involving a sinus lift procedure or bone grafting were excluded. The records of all eligible cases were assessed for prosthetic complications including screw loosening or fracture and ceramic de-lamination. Mesial and distal bone height around the implants was measured on digital radiographs by one examiner. A total of 455 patients (151 males; 304 females) had 1673 implants. The mean age of males (53.7 years, SD 14.6) was significantly greater than that of females (49.3 years, SD 12.9, p<0.001). The lower left and right posterior sextants were the most frequent sites for implants while the lower anterior sextant was the least common. Mean mesial crestal bone loss in implant supported-fixed prostheses was significantly greater (1.14mm, SD 0.63) compared to single implant-supported prostheses (0.30mm, SD 0.43, p<0.001). Mean distal crestal bone loss was also significantly greater (1.29mm, SD 0.71) in implant supported-fixed prostheses than in single implant-supported prostheses (0.36mm, SD 0.54, p<0.001). Mean crestal bone loss mesially and distally in patients with a medical condition (N=165) was significantly greater compared to medically fit patients (N=290, p<0.001). Mean mesial and distal bone loss was significantly greater around implants placed in the lower anterior sextant compared to all the other sites (p<0.001). A total of 66 cement retained implants had significantly more complications than expected compared to the 1607 screw retained implants (Fisher’s Exact test, p<0.001). Implant supported-fixed prostheses have greater bone loss than single implant supported prostheses. Age, position in the mouth and having a medical condition are factors that influence bone loss.