Long-term follow-up of hydroxyapatite-coated dental implants--a clinical trial.

PURPOSE: The purpose of this study was to report the long-term (8- to 10-year) results of hydroxyapatite (HA) -coated dental implants and compare them to the 5-year results as well as to long-term results of both HA and titanium dental implants reported in the literature. MATERIALS AND METHODS: Patients were recruited, screened, and accepted or rejected sequentially based on specific inclusion/exclusion criteria. Implant placement was performed according to the manufacturer's instructions, followed by prosthetic reconstruction. Routine follow-up examinations were performed for a 5-year period. At 10 years all patients were contacted by mail and invited to participate in a longer-term follow-up of dental implants. All participants provided informed consent and underwent a complete history, including clinical and radiographic examination. The data obtained were statistically analyzed using life tables. RESULTS: A total of 302 implants were placed in 90 patients whose average age was 54.3 years (SD 13.2 years). Of these, 114 implants in 40 patients were examined at 10 years, 88 in the mandible and 26 in the maxilla. The cumulative survival rate was 85.40% in the mandible and 70.59% in the maxilla. The total survival rate was 81.97%. CONCLUSIONS: The 10-year success rate of HA-coated dental implants was 82%. The success rate is higher in the mandible as compared to the maxilla. The 10-year results are inferior to the 5-year results. (Clinical Trial)

Furcation therapy with bioabsorbable collagen membrane: a clinical trial.

This study compared the effectiveness of 2 barrier membranes, expanded polytetrafluoroethylene (e-PTFE) and collagen, in treating Class II furcation defects of mandibular molars in humans. Seventeen nonsmoking subjects with no history of systemic disease each presenting with Class II furcation defects in 2 mandibular molars were selected and underwent initial therapy. At the time of the surgery and at 8-month follow-up, soft-tissue measurements consisting of the gingival index, vertical and horizontal probing depth, recession and clinical attachment level were obtained at the midfurcation level. At the time of membrane placement and at 12-month re-entry, horizontal midfurcation probing depth and hard-tissue measurement of vertical fill (from the crown to the depth of the pocket) were also obtained. According to the surgical protocol, both membranes were completely covered with a coronally positioned flap, and in all cases healing was uneventful. Data were analyzed first by comparing baseline measurements (at surgery) with measurements at 8-month follow-up and 12-month re-entry for both e-PTFE and collagen membranes according to repeated-measures analysis of variance. The changes from surgery to follow-up and re-entry were then compared between the 2 treatment modalities with paired Wilcoxon rank-sum tests. No statistically significant differences were found between e-PTFE and collagen membranes with respect to gingival index, reduction in probing depth, gain in clinical attachment or filling of the horizontal defect. However, the improvement in vertical fill at 12-month re-entry was more substantial for the teeth treated with collagen membrane than those treated with e-PTFE (p < 0.05). Within the limits of this study, it appears that collagen is a beneficial material for regenerative therapy of Class II furcation defects in humans, yielding results that are similar to or better than (vertical fill) those for e-PTFE membrane.