The Effects of Photobiomodulation on Leukocyte and Platelet-Rich Fibrin as Barrier Membrane on Bone Regeneration: An Experimental Animal Study.

Objective: To compare the effects of leukocyte and platelet-rich fibrin (L-PRF) and photobiomodulation therapy (PBMT)-applied L-PRF (PBMT/L-PRF) as barrier membranes on new bone formation (BV/TV) for the treatment of critical-sized bone defects. Materials and methods: The right iliac crests of five sheep were used in this experimental animal study. Eight critical-sized defects were surgically created in each sheep and a total of 40 defects were obtained. A deproteinized bovine bone graft was placed in all defects, and the defects were divided into four groups to be covered with L-PRF membrane, PBMT/L-PRF membrane, collagen membrane, or left uncovered as controls. Animals were sacrificed at 1 month. The sections obtained were histomorphometrically analyzed. Results: The results showed that the collagen group presented significantly higher values for main bone healing parameters (BV/TV, bone volume, and bone surface; p < 0.05). The PBMT/L-PRF group presented higher values than the L-PRF group and controls for these parameters though not statistically significant (p > 0.05). Conclusions: The findings show that PBMT may provide additional regenerative properties to L-PRF when used as barrier membranes. However, these results did not reach the collagen membranes, which warrants further studies for adapting the laser parameters to increase regenerative capacity of L-PRF.

The effects of repeated usage of implant drills on cortical bone temperature, primary/secondary stability and bone healing: A preclinical in vivo micro-CT study.

OBJECTIVE: The aims of the study were to evaluate the effects of new vs. used drills on cortical bone temperature, operation time, and primary/secondary stability and to assess bone healing by micro-CT. MATERIALS AND METHODS: New, 50×-used and 100×-used drills at 800 rpm were used to place implants in the iliac crests of three male sheep in this experimental in vivo animal study. A total of 36 implants (12 in each group) were placed. The temperature of the cortical bone was recorded with an infrared thermometer, and the ISQ values at implant placement (primary stability) and at 4 weeks (secondary stability) were evaluated. The bone volume assessed by micro-CT was used to evaluate bone tissue healing. The results were statistically compared. RESULTS: The results have shown that the operation time and the cortical bone temperature increased by the usage of the drills (p < .05) and the primary/secondary stability (ISQ values) decreased with the number of drill usage (p < .05) The highest 2- and 3-dimensional bone volume (assessed by micro-CT) were noted for new drills group followed by 50×-used drills and 100×-used drills (p < .05 at 4 weeks). CONCLUSION: The number of drill usage seems to be directly affecting the osseointegration process in implant surgery. Therefore, replacing the drills at certain time intervals may increase the success of implant treatment.

Clinical evaluation of injectable platelet-rich fibrin with connective tissue graft for the treatment of deep gingival recession defects: A controlled randomized clinical trial.

AIM: The aim of this study was to determine whether the combined connective tissue graft (CTG) with injectable platelet-rich fibrin (i-PRF) with coronally advanced flap (CAF) improved root coverage of deep Miller Class I or II gingival recessions compared with CTG alone with CAF. MATERIAL AND METHODS: Seventy-two patients with Miller class I and II gingival recessions were enrolled. Thirty-six patients were randomly assigned to the test group (CAF+CTG+i-PRF [700 rpm for 3 min]) or control group (CAF+CTG). Clinical evaluations were made at 6 months. RESULTS: At 6 months, complete root coverage was obtained at 88% of the sites treated with CAF+CTG+i-PRF and 80% of the sites treated with CAF+CTG. Difference between the two groups was not statistically significant. At 6 months, the recession depth (RD) reduction and increase in keratinized tissue height (KTH) of the test sites were significantly better compared with the control sites. CONCLUSIONS: According to the results, the addition of i-PRF to the CAF+CTG treatment showed further development in terms of increasing the KTH and decreasing RD. However, this single trial is not sufficient to advocate the true clinical effect of i-PRF on recession treatment with CAF+CTG and additional trials are needed.