RESUMO
Leukocyte-platelet-rich fibrin (L-PRF) contains growth factors that stimulate bone regeneration. This study evaluated the bone repair in a tibia rat model around two implant surfaces in combination or not with L-PRF by assessing microtomographic and histomorphometric parameters. A total of 48 female rats were used in the study, in which 24 received implants with two types of surface treatments (dual acid etched-DAE or nanohydroxyapatite-nanoHA), and the other 24 received the same mini implants with L-PRF, which was collected by cardiac puncture, centrifugated, and inserted in the bone bed. The animals were euthanized 7 and 30 days after implant placement, and the retrieved samples were prepared for microtomographic and histomorphometric (bone-to-implant contact-BIC; and Bone Area Fraction Occupancy-BAFO) analyses. The adhesion of the nanoHA surface onto the implant surface was investigated by insertion and removal in simulated bone medium (Sawbones). The adhesion evaluation revealed that the loss of nanoHA after this procedure (as measured with SEM) from the implant surface was less than 1%. Overall, the nanoHA surface presented more bone in contact and in proximity to the implant, a higher bone surface/tissue volume fraction, a higher number of bone trabeculae, as well as trabecular separation relative to the DAE surface. Such results were more evident when the nanoHA surface was combined with L-PRF and after 30 days in vivo. The nanoHA surface presented higher BAFO when compared to DAE, with or without association with L-PRF. Therefore, implants with a nanoHA surface potentially benefit from the association to L-PRF.
RESUMO
The aim of this study was to evaluate the bone response to two different implant surfaces on sinus lift procedures in rabbits. Bilateral sinus lifting with inorganic bovine bone associated with collagen membrane and immediate implantation were performed in 16 rabbits. Custom mini-implants were randomly installed in the prepared sites: one side received a double acid-etched (DAE) surface and the other a nano-hydroxyapatite (NHA) surface. The animals were euthanized 30 and 60 days after surgery, and biopsies were collected for microtomographic and histomorphometric analysis. After 30 days, no intra- and inter-group statistical differences were observed in microtomographic analysis, while at 60 days, bone analysis showed statistically significant differences between groups (p < 0.05) for all the evaluated parameters. Histomorphometric analysis showed, after 30 days, mean % of Bone-to-Implant Contact (BIC) for DAE and NHA of 31.70 ± 10.42% vs. 40.60 ± 10.22% (p > 0.05), respectively; for % of Bone Area Fraction Occupancy (BAFO), mean values were 45.43 ± 3.597% for DAE and 57.04 ± 5.537% for NHA (p < 0.05). After 60 days, mean %BIC and %BAFO for DAE and NHA implants were statistically significant (p < 0.05). The NHA surface showed superior biological features compared to the DAE treatment, promoting higher bone formation around the implants in an experimental model of bone repair in a grafted area.
RESUMO
BACKGROUND: This double-blind, randomized, controlled clinical trial assessed the efficacy of multiple sessions of antimicrobial photodynamic therapy (aPDT) as an adjunct to surgical periodontal treatment (ST) in patients with severe chronic periodontitis (SCP). METHODS: Sixteen patients with SCP were treated with aPDT+ST (test group, TG) or ST only (control group, CG), in a split-mouth design. aPDT was applied at 0, 2, 7, and 14 postoperative days only in TG. All patients were followed up for 90 days after surgery. The following clinical and microbiological parameters were assessed: clinical attachment level (CAL), probing depth (PD), gingival recession (GR), bleeding on probing (BOP), plaque index (PI), and count of 40 subgingival microbial species (checkerboard DNA-DNA hybridization). Data were collected at baseline (preintervention), at 60 days (30 days after the end of non-surgical therapy), and at 150 days (90 days after surgery). RESULTS: A significant reduction in PD was observed at 150 days for the TG, when compared with the CG (P Ë 0.05). CAL gain was significantly higher in the TG at 60 and 150 days (P Ë 0.05). Changes in the subgingival microbiota were similar between the groups (P Ë 0.05), but the TG revealed a larger number of bacteria associated with periodontal disease at the end of the experiment compared with the CG (P < 0.05). CONCLUSION: Multiple sessions of aPDT as an adjunct to surgical periodontal treatment significantly improved clinical parameters at 90 postoperative days.