Stability of dental implants after irradiation with an 830-nm low-level laser: a double-blind randomized clinical study.

Little is known about the benefits of low-level laser therapy (LLLT) on improvement of stability of dental implants. The aim of this randomized clinical study was to assess the LLLT effect on implants stability by means of resonance frequency analysis (RFA). Thirty implants were distributed bilaterally in the posterior mandible of eight patients. At the experimental side, the implants were submitted to LLLT (830 nm, 86 mW, 92.1 J/cm(2), 0.25 J, 3 s/point, at 20 points), and on the control side, the irradiation was simulated (placebo). The first irradiation was performed in the immediate postoperative period, and it was repeated every 48 h in the first 14 days. The initial implant stability quotient (ISQ) of the implants was measured by means of RFA. New ISQ measurements were made after 10 days, 3, 6, 9, and 12 weeks. The initial ISQ values ranged from 65-84, with a mean of 76, undergoing a significant drop in stability from the 10th day to the 6th week in the irradiated group, and presenting a gradual increase from the 6th to the 12th week. The highest ISQ values were observed on the 10th day in the irradiated group, and the lowest in the 6th week in both groups. Under the conditions of this study, no evidence was found of any effect of LLLT on the stability of the implants when measured by RFA. Since high primary stability and good bone quality are of major relevancy for a rigid bone-implant interface, additional LLLT may have little impact macroscopically.

Clinical and Histomorphometric Evaluation of Fresh Frozen Bone Allograft in Sinus Lift Surgery.

PURPOSE: The aim of this prospective clinical study was to evaluate the clinical and histomorphometric data of newly formed bone tissue from fresh frozen human allograft in sinus lift surgery. PATIENTS AND METHODS: Thirty-three sinus lift procedures were performed in 20 patients, divided into two groups. The control group (n = 8) received autogenous bone from the mandibular ramus, and the experimental group (n = 12) received fresh frozen bone (FFB) allograft in chips. After 6 months, 52 implants were placed and 50 biopsies were collected for histomorphometric analysis. Cone beam computed tomography scans were performed at preoperative, immediate postoperative, and delayed postoperative time intervals to assess the degree of graft volume loss. RESULTS: There was no statistically significant difference between groups as regards degree of graft volume loss (p = .983), total bone area (p = .191), remaining particles (p = .348), and proportion of active osteoblasts (p = .867). There was a statistically significant difference in the vitality rate between the groups (p = .043). In both groups, all implants were clinically osseointegrated after 4 months. CONCLUSION: FFB allograft was shown to be a feasible substitute for autogenous bone graft in sinus lift surgery.