Raloxifene enhances peri-implant bone healing in osteoporotic rats.

The aim of this study was to evaluate bone healing at the bone-implant interface in rats with induced osteoporosis. The rats underwent a bilateral ovariectomy (OVX) and were fed a low calcium and phosphate diet. The OVX rats were divided into three groups: one was treated with raloxifene (OVX-RAL), one with alendronate (OVX-ALE), and one received no medication (OVX-NT). The control group rats (SHAM-DN) underwent sham surgery and were fed a normal diet. Each animal received one implant in each tibia: a machined surface implant in the right tibia and an implant with surface etching in the left tibia. All animals were euthanized after 42 days. Analysis of variance (ANOVA) and Tukey post hoc tests were applied to the biomechanics (reverse torque) and bone-implant contact (BIC) data (P<0.05). The RAL and ALE groups showed improved peri-implant bone healing. However, the ALE group showed no significant difference from the OVX-NT group. Surface treatment promoted higher corticalization at the bone-implant interface, but showed the same characteristics of mature bone and bone neoformation in concentric laminations as the machined implant. There were no statistically significant differences in reverse torque (P=0.861) or BIC (P=0.745) between the OVX-RAL and SHAM-DN groups. Therefore, the use of raloxifene resulted in good biomechanical, BIC, and histological findings in the treatment of induced osteoporosis in rats.

Influence of the association between platelet-rich fibrin and bovine bone on bone regeneration. A histomorphometric study in the calvaria of rats.

This study aimed to investigate the effects of platelet-rich fibrin (PRF) associated or not with Bio-Oss on bone defects in the calvaria of rats. A critical-size defect of 5-mm diameter was performed in the calvaria of 48 rats. These animals were divided into six groups of eight animals each, according to the treatment received: homogeneous clot, autogenous clot, autogenous PRF, homogeneous PRF, Bio-Oss, or Bio-Oss associated with PRF. The animals were euthanized after 30 or 60 days. Bone regeneration was evaluated by histomorphometric analysis. The highest mean percentages of new bone formation at 30 days (54.05% ± 5.78) and 60 days (63.58% ± 5.78) were observed in the Bio-Oss associated with PRF group; in particular, the percentage of new bone at 30 days was significantly higher than that of all of the other groups (P<0.01). At 60 days, the Bio-Oss associated with PRF (63.58% ± 5.78) and Bio-Oss (57.34% ± 5.78) groups had similar results, and both showed a statistical difference compared to the other groups. PRF had a positive effect on bone regeneration only when associated with Bio-Oss.

Survival rate of osseointegrated implants in atrophic maxillae grafted with calvarial bone: a retrospective study.

The aim of this study was to evaluate the clinical survival rate of osseointegrated implants placed in the atrophic maxilla that has been reconstructed by means of autogenous bone grafts harvested from a cranial calvarial site. Further, we sought to analyse the level of peri-implant bone after prosthetic rehabilitation and to determine subjective patient satisfaction with the treatment performed. This study conformed to the STROBE guidelines regarding retrospective studies. Twenty-five patients who had received osseointegrated implants with late loading in the reconstructed atrophic maxilla were included in the study. The survival rate and level of peri-implant bone loss were evaluated. A questionnaire related to the surgical and prosthetic procedures was completed. The observed implant survival rate was 92.35%. The mean bone loss recorded was 1.76mm in the maxilla and 1.54mm in the mandible. The results of the questionnaire indicated a high level of patient satisfaction, little surgical discomfort, and that the patients would recommend the procedure and would undergo the treatment again. From the results obtained, it is concluded that the cranial calvarial site is an excellent donor area; calvarial grafts provided stability and maintenance of bone volume over the course of up to 11 years.

Cephalometric and three-dimensional assessment of superior posterior airway space after maxillomandibular advancement.

The purpose of this study was to quantify cephalometric and three-dimensional alterations of the posterior airway space of patients who underwent maxillomandibular advancement surgery. 20 patients treated by maxillomandibular advancement were selected. The minimal postoperative period was 6 months. The treated patients underwent cone-beam computed tomography at 3 distinct time intervals, preoperative (T1), immediate postoperative period up to 15 days after surgery (T2), and late postoperative period at least 6 months after surgery. The results showed that the maxillomandibular advancement promoted an increase in the posterior airway space in each patient in all the analyses performed, with a statistically significant difference between T2 and T1, and between T3 and T1, p<0.05. There was a statistical difference between T2 and T3 in the analysis of area and volume, which means that the airway space became narrower after 6 months compared with the immediate postoperative period. The maxillomandibular advancement procedure allowed great linear area and volume increase in posterior airway space in the immediate and late postoperative periods, but there was partial loss of the increased space after 6 months. The linear analysis of airway space has limited results when compared with analysis of area and volume.

Nasolacrimal stents in the management of epiphora: medium-term results of a multicenter prospective study.

PURPOSE: To evaluate in a prospective multicenter setting the clinical utility of polyurethane stents in the percutaneous management of epiphora. MATERIALS AND METHODS: Patients (N = 163; age range = 22-85 y, mean = 52 y; 29 men, 134 women) with severe epiphora had stents (n = 183) inserted under fluoroscopic guidance in 180 lacrimal systems (unilateral = 146; bilateral = 17) to treat complete (n = 172) or partial (n = 8) obstruction of the nasolacrimal duct or sac. The junction between sac and duct was the most frequent location (n = 102), followed by the sac alone (n = 48), and the duct alone (n = 30). The etiology of the obstruction was idiopathic in 113 cases (63%) and chronic dacryocystitis in 67 (37%). The set designed by Song was used in all patients and the original technique was slightly modified by the authors. All patients were treated on an outpatient basis. Average time of the procedure was 14 minutes (range = 3-70 min). RESULTS: Initial technical success rate of stent placement was 97%. Resolution of epiphora was complete in 175 eyes and partial in five. On follow-up (mean = 450 d; range = 8-730 d), 157 of 183 stents remained patent (85.8%). Of the 24 obstructed, 19 were easily withdrawn and 17 of these patients remained asymptomatic for a mean of 15 months (secondary patency rate = 89.5%). CONCLUSIONS: The procedure is simple and safe. It can be performed on an outpatient basis and the original technique could be improved with some technical modifications. It is well tolerated by patients and may be considered as a valid alternative technique for the resolution of epiphora.

Osseous regeneration in the presence of fibrin adhesive material (Tissucol) and epsilon-aminocaproic acid (EACA).

The effects of Tissucol and Tissucol/EACA on bone healing were evaluated histologically. Experimental defects were made in both tibias of 25 rats. Test materials were placed in defects in right tibias and left tibias served as control. Five animals in each group were killed at 1, 3, 7, 14 and 21 days after surgery. Results showed that: a) Tissucol did not interfere with connective and osseous tissue formation; b) Tissucol allowed new bone formation; c) Tissue residues in Tissucol groups in sections of 21-day specimens did not impair healing; d) Tissucol/EACA was usually completely resorbed and healing was complete 21 days after surgery in the Tissucol/EACA group.