Immediate implant placement in posterior maxilla: a prospective clinical study

Aim The aim of present study is to comparatively evaluate the survival rate of immediate implants in maxillary molar region depending upon the availability of remaining subsinus alveolar bone and also an attempt to develop a protocol for immediate implant placement with minimally invasive surgical procedures for successful outcome.

Materials and methods A total of 123 patients with root stumps, grossly decayed and non-salvageable molar teeth were included in the present study. Depending upon available subsinus bone patients, subjects were divided in three groups. Group 1 consisted of patients with sufficient interradicular bone septum height (more than 8 mm),  Group 2 with sinus invagination and interradicular bone septum height between 6-8 mm and Group 3 with sinus invagination and interradicular bone septum height between 4-6 mm. After careful extraction, in Group 1, 11.5 or 13 mm long implants were placed in the interradicular bone. In Group 2, 10 or 11.5 mm long implants were placed after performing indirect sinus lift through the socket. In Group 3, direct sinus lift was performed and 8 mm long implants were placed. All the patients were regularly followed up for a minimum period of 3 years.

Results In total 112 patients completed the 3-year follow-up; a total of 146 implants were placed: 42 in group 1, 51 in group 2 and 53 in group 3. At 3 years follow-up, group 1, 2 and 3 demonstrated a survival rate of 97.8%, 94.2% and 86.8% respectively. Overall survival rate was 90.17%.

Conclusion Thorough preoperative clinical and radiographic assessment of the case is mandatory, and patients should be made aware regarding the complications and failures that may occur. Of course, complication and failures can happen even to skilled operators, but careful extraction, skillful implant placement in the extraction socket and operator experience are the key of success.