The clinical prognosis of implants that are placed against super-erupted opposing dentition

OBJECTIVES: If teeth are missing, super-eruption of teeth in the opposing arch can occur in the area and can change the occlusal plane. When missing teeth are replaced with implants, the oral surgeon must determine whether or not the super-erupted teeth need to be treated in order to normalize the occlusal plane. In this study, we evaluated the clinical prognosis of dentition after implant placement and prosthetic treatment were completed in an occlusal plane altered by super-erupted teeth in the opposing arch without additional treatment of the super-erupted teeth. MATERIALS AND METHODS: Twenty-two patients (9 males, 13 females) were treated with implants and prosthetics without addressing the super-erupted opposing dentition from April 2004 to August 2012 at Seoul National University Bundang Hospital. A total of 33 implants were placed. Values of crestal bone loss, survival rates, and surgical and prosthetic complications for an average of 29.6 months after prosthetic loading were recorded. RESULTS: In one case, the cover screw was exposed after implant surgery. The mean crestal bone loss was 0.09±0.30 mm. Of the 33 implants, 31 survived, a survival rate of 93.94%. A prosthetic complication occurred in one case but functioned well after correction. CONCLUSION: Favorable clinical results from prosthetic complications, crestal bone loss, and implant survival rates were exhibited in implants next to a super-erupted opposing tooth.

Reconstruction of Defect after Treatment of Bisphosphonate-related Osteonecrois of the Jaw with Staged Iliac Bone Graft / 대한악안면성형재건외과학회지

Bisphosphonate is used widely for osteoporosis treatment, but a rising concern is the risk of osteonecrosis after long-term bisphosphonate use. Such cases are increasing, suggesting a need for research to prevent and treat bisphosphonate-related osteonecrosis of jaws. A 63-year-old female took bisphosphonate (Fosamax(R)) for four years for treatment of osteoporosis and stopped medication two months ago because of unhealed wound. She was treated with marginal mandibulectomy maintaining the inferior border, and a metal plate was placed to prevent mandible fracture. Four months after the mandibulectomy, mandible reconstruction surgery using iliac bone and allograft was done. Six months after reconstruction, implant placement and treatment with an overdenture was done without complications. This study presents a case with a successful result.

A prospective study on the effectiveness of newly developed autogenous tooth bone graft material for sinus bone graft procedure

PURPOSE: The purpose of this prospective study was to evaluate the effectiveness of newly developed autogenous tooth bone graft material (AutoBT)application for sinus bone graft procedure. MATERIALS AND METHODS: The patients with less than 5.0 mm of residual bone height in maxillary posterior area were enrolled. For the sinus bone graft procedure, Bio-Oss was grafted in control group and AutoBT powder was grafted in experimental group. Clinical and radiographic examination were done for the comparison of grafted materials in sinus cavity between groups. At 4 months after sinus bone graft procedure, biopsy specimens were analyzed by microcomputed tomography and histomorphometric examination for the evaluation of healing state of bone graft site. RESULTS: In CT evaluation, there was no difference in bone density, bone height and sinus membrane thickness between groups. In microCT analysis, there was no difference in total bone volume, new bone volume, bone mineral density of new bone between groups. There was significant difference trabecular thickness (0.07 microm in Bio-Oss group Vs. 0.08 microm in AutoBT group) (P=.006). In histomorphometric analysis, there was no difference in new bone formation, residual graft material, bone marrow space between groups. There was significant difference osteoid thickness (8.35 microm in Bio-Oss group Vs. 13.12 microm in AutoBT group) (P=.025). CONCLUSION: AutoBT could be considered a viable alternative to the autogenous bone or other bone graft materials in sinus bone graft procedure.

Effect of loading time on marginal bone loss around hydroxyapatite-coated implants

OBJECTIVES: The objective of this study is compare the rate of marginal bone resorption around hydroxyapatite-coated implants given different loading times in order to evaluate their stability. MATERIALS AND METHODS: The study was conducted retrospectively for one year, targeting 41 patients whose treatment areas were the posterior maxilla and the mandible. Osstem TS III HA (Osstem Implant Co., Busan, Korea) and Zimmer TSV-HA (Zimmer Dental, Carlsbad, CA, USA), which employ the new hydroxyapatite coating technique, were used. The patients were divided into two groups - immediate and delayed loading - and the bone level at the time of loading commencement and after one year of loading was measured using periapical radiography. Differences between the groups were evaluated using Mann-Whitney (alpha=0.05). RESULTS: For all patients as a single group, the survival rate of the implants was 100%, and the mean marginal bone loss was 0.26+/-0.59 mm. In comparison of the differences by loading, mean marginal bone loss of 0.32+/-0.69 mm was recorded for the immediate loading group whereas the delayed loading group had mean marginal bone loss of 0.16+/-0.42 mm. However, the difference was not significant (P>0.05). CONCLUSION: Within the limited observation period of one year, predictable survival rates can be expected when using immediately loaded hydroxyapatite-coated implants.