Teriparatide improves alveolar bone modelling after tooth extraction in orchiectomized rats.

OBJECTIVE: The aim of this study was to evaluate bone metabolism in the alveolar repair process in orchiectomized male rats treated with teriparatide. MATERIALS AND METHODS: A total of 78 rats were divided into three groups: 26 oriectomized rats treated with teriparatide (ORQTRAT), 26 untreated orchiectomized rats (ORQ), and 26 rats which had undergone sham surgical procedures (SHAM), all these animals underwent extraction of the central incisor tooth. Thus, a histological analysis was performed (42 days). Real Time PCR (14 and 42 days) and immunohistochemical (42 days) analyses were performed based on the expression of RANK-L and osteoprotegerin (OPG). The calcein and alizarin were analyzed via laser confocal microscopy to verify alveolar bone turnover, and microtomographic analysis was performed to determine volume and bone quality (calcified tissues). In this analysis, the euthanasia period was 60 days post-extraction. The quantitative data were submitted to the statistical test and the significance level of 5% was adopted. RESULTS: Teriparatide increased bone turnover with a higher relative gene expression of RANKL and OPG at 14 days, and at 42 days, there was a significant decrease of RANKL and an increase of OPG, this standard can also be evaluated in the ratio of RANKL to OPG. Greater values of area and bone mineral deposition were found for the ORQTRAT group (p < 0.05), along with higher bone volume values (p < 0.05). The immunolabels revealed greater intensity in the relationship of RANKL and OPG, which led to intense remodeling aiding in the process of bone formation. CONCLUSION: The teriparatide treatment in orchiectomized rats increases bone volume and decreases the porosity, in addition to promoting greater intensity in bone turnover during alveolar repair.

Effect of intermittent teriparatide (PTH 1-34) on the alveolar healing process in orchiectomized rats.

OBJECTIVE: To evaluate intermittent teriparatide therapy's influence on the alveolar healing process in rats with induced osteoporosis. MATERIALS AND METHODS: Fifty-four male rats were divided into three groups: fictitious surgery (SHAM), bilateral orchiectomy (ORQ NT), and bilateral orchiectomy treated with teriparatide (ORQ TERI). Right upper incisor extraction was performed. After 14 and 42 days, the rats were euthanized. Immunolabeling analysis was performed in order to characterize bone turnover through Wnt, alcaline phosphatase, osteocalcin, and TRAP presence in tissue; micro-CT analysis was performed in order to determine the bone volume fraction (BV/TV), trabecular thickness, separation, and number (Tb.Th, Tb.Sp, Tb.N). For the micro-CT data, statistical analysis was performed through one-way ANOVA and Tukey post-test, for parametrical data, with significance level adopted in p < 0.05. Days, Wnt, alkaline phosphatase, and osteocalcin revealed more labeling for ORQ TERI and less for TRAP. For the Tb.N in the ORQ NT group was 0.496 mm, a significant statistical difference was observed between the groups of ORQ NT and ORQ TERI (p < 0.05). For the BV/TV, Tb.Sp, and Tb.Th parameters, no significant statistical difference was observed among the three experimental groups (p > 0.05). CONCLUSIONS: Treatment with intermittent teriparatide reverted impairment in the metabolism of repairing bone tissue in orchiectomized animals. CLINICAL RELEVANCE: Cases of decreased bone density such as osteoporosis can lead to delayed alveolar repair process. PTH 1-34 has been shown to be a medication that improves this repair, making bone of low quality into one with normal features.

Effect of antiresorptive drugs in the alveolar bone healing. A histometric and immunohistochemical study in ovariectomized rats.

OBJECTIVES: The aim of this study is to evaluate the alendronate and raloxifene influence in the alveolar healing process of osteoporotic rats. MATERIALS AND METHODS: Sixty-four female rats were divided in four groups: sham rats (SHAM), ovariectomized rats and no medical treatment (OVX NT), ovariectomized rats and submitted to alendronate treatment (OVX ALE), and ovariectomized and submitted to raloxifene treatment (OVX RAL). The histomorphometrical and immunohistochemical analysis was performed. The quantitative data were analyzed through Kruskal-Wallis and Dunn tests (α = 0.05). RESULTS: In the longest period, SHAM and OVX RAL groups showed the better bone formation responses (P < 0.05). The worst bone formation response was observed in the group OVX NT. OVX RAL group showed the better response at 42 days. OVX ALE group showed a favorable response at 14 days, in comparison with OVX RAL group, but a reduced response at 42 days. It was possible to observe a mature bone in SHAM group at 14 days and an immature bone in the OVX NT group. An intermediate quality bone was observed in the groups OVX ALE and OVX RAL. CONCLUSION: Alendronate and raloxifene treatment improved the alveolar healing process in osteoporotic rats, but not enough to achieve the histometrical and protein expression values that were observed in the SHAM group. CLINICAL RELEVANCE: Alendronate is largely used as a potent antiresorptive agent. Otherwise, considering the undesirable effects in relation to the alveolar healing, other antiosteoporosis medications should be studied. Raloxifene seems to be a good candidate once its action mechanism involves the activation of osteoblasts.

Unerupted lower third molar extractions and their risks for mandibular fracture.

As every surgical procedure extraction of third molars can result in several complications, among them the mandibular angle fracture. Predisposing factors for fracture should be analyzed during and after the surgery. This paper aims to discuss the predisposing factors to the occurrence of mandibular angle fractures during and after the procedure for third molars extraction, as well as surgical principles to avoid this complication.