Implant treatments of posterior molar regions with short implants ( 8 or 6 mm length): Clinical results after 3 years

Abstract

There are anatomical limitations in posterior maxilla and mandible for treating with dental implants. Short implant has recently gained a great attention to avoid complications associated with implant treatment in these regions. Although clinical studies with short implants in these regions have been reported, real outcomes of short implants have not been clear yet. The purpose of the present study was to evaluate implant treatments with short implants (6 and 8 mm in length) and long implants (9, 11, 13 mm in length) in posterior molar regions retrospectively. This clinical study was approved by the ethical committee of the institute. Forty five patients received 48 short implants whereas 59 patients received 110 long implants. After a sufficient non-loaded period, 2-3 months in mandible and 4-5 months in maxilla, the secondary surgeries were performed and the final prostheses of cement fixation were delivered. Clinical assessments were done three years after delivering the final prostheses. All the procedures from the surgeries, the prosthodontic steps and the maintenances were performed by the first author. At the secondary surgery, 6 short implants did not integrate with bone, in which 2 implants were placed in the very hard mandibular bone and other 4 implants were exposed after the surgery resulting in extensive bone loss. Four long implants also did not integrate with bone at the secondary surgery, which were also placed in hard mandibular bone. In the osseointegrated 42 short implants, 20 implants were single crown restorations whereas 22 implants were splinted. At 3 years all the 42 short implants were functioning. Radiographically, the periimplant bone loss around the short implants and the long implants was 0.14 ± 0.29 mm and 0.29 ± 0.61, respectively (mean ± SD) Although the 6 short implants were not osseointegrated, these failed cases could be avoided with more surgical attentions. The results of the present study indicate that implant treatments with short implants in posterior regions of anatomical restrictions are clinically effective.