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Objectives: Alendronate and raloxifene, a bisphosphonate and a selective estrogen modulator, respectively, are established osteoporosis therapies. Current evidence suggests that simultaneous application of osteoporosis therapies modulates osseointegration. However, alendronate shows inconsistent findings and raloxifene has not been studied comprehensively. This study aimed to evaluate the bone dynamics and molecular and microstructural features at the peri-implant bone interface in osteoporotic rats., Materials and Methods: Thirty female rats underwent ovariectomy and were fed a diet low in calcium and phosphate and treated with alendronate or raloxifene for 30 days or underwent fictional ovariectomy surgery (SHAM) prior to implant insertion in the tibia; osteoporosis therapies continued thereafter. After 42 days, peri-implant bone was evaluated by histometric and micro-CT analysis. Fluorochrome incorporation and gene expression was determined to evaluate bone turnover., Results: We report here that alendronate had no impact on bone-to-implant contacts and the mineral apposition rate. The RANKL/OPG ratio and local bone volume, however, were increased compared to the untreated osteoporotic rats. Even though signaling to bone resorption activity through RANKL production was observed in the alendronate group, the blockade of bone resorption activity that occurs in decorrence to alendronate activity took place and resulted in an increase in bone volume. Raloxifene significantly increased osseointegration in osteoporotic rats, as indicated by bone-to-implant contacts, mineral apposition, and local bone volume. Raloxifene, however, had no considerable impact on the RANKL/OPG ratio compared to untreated osteoporotic rats. As expected, the SH group showed higher bone-to-implant contacts and mineral apposition rates than the untreated osteoporotic rats., Conclusions: These findings suggest that raloxifene but not alendronate can compensate for the impaired osseointegration in osteoporotic rats., Clinical Relevance: Regarding the superiority of raloxifene observed in the improvement of bone dynamics response, this statement suggests that raloxifene could be a good option for osteoporosis patients in oral rehabilitation procedures.

The purpose of this study was to evaluate the association of the combination of polylactic/polyglycolic acid around implants installed with and without primary stability through the histometric analysis of bone-implant interface. We used male rabbits, each of which received 2 titanium implants in each tibial metaphysis. The animals were divided into 4 groups: control with primary stability (CPS), control without primary stability (C), polymer with primary stability (PPS), and polymer without primary stability (P). Euthanasia was performed at postoperative days 40 and 90. The pieces were embedded in resin, sectioned, scraped, and stained with alizarin red and Stevenel blue. Histometric analysis evaluated the linear extension of contact between the bone and implant surface on the implant collar (CIC) and contact between the bone and implant surface on the first thread (CFT). Also evaluated was the area of newly formed bone (ANB) in the first thread. The results showed that there was new bone formation in all groups and during all periods. At 40 days, the ANB was higher in the PPS group than in the P group (P < .001); the CFT was statistically higher in the CPS group than the PPS group (P < .001) and was higher in the CPS group than the C group (P < .001). At 40 and 90 days, the CIC was higher in the P group than in the C group (P < .001). In conclusion, the copolymer had biocompatibility, enhanced bone healing, and presented osteoconductive properties, thus raising the contact between bone and implant, even without primary stability.

Background Hypertension is considered a risk factor in implant dentistry but the underlying reasons remain unclear. It may be that hypertension has a negative impact on the local bone quality. Purpose Here we evaluated the structural and histological parameters of bone collected from hypertensive patients treated by antagonists of the renin-angiotensin system, and of bone collected from normotensive patients. Material and methods A total of 30 patients were referred for rehabilitation with dental implants to be placed in the posterior mandible. The first group were hypertensive patients treated with RAS antagonists. The second group were normotensive patients not taking medication. Bone biopsies collected during implant installation were subjected to analysis. Micro CT revealed the structural parameters. Histological analyses together with immunohistochemical staining of osteogenic markers were performed. Results The structural parameters of bone volume, trabecular thickness, trabecular number, separation of the trabecular, and total porosity were similar between the 2 groups ( P > .05). The histological appearance of bone derived from hypertensive patients was normal. The staining pattern of Runx-2, osteopontin, and osteocalcin were comparable in both groups. Conclusions These observations suggest that hypertensive patients treated with renin-angiotensin system antagonists have regular alveolar bone with respect to bone structure and histological parameters. [ABSTRACT FROM AUTHOR]

Empirical concepts describe the direction of the masticatory stress dissipation in the skull. The scientific evidence of the trajectories and the magnitude of stress dissipation can help in the diagnosis of the masticatory alterations and the planning of oral rehabilitation in the different areas of Dentistry. The Finite Element Analysis (FEA) is a tool that may reproduce complex structures with irregular geometries of natural and artificial tissues of the human body because it uses mathematical functions that enable the understanding of the craniofacial biomechanics. The aim of this study was to review the literature on the advantages and limitations of FEA in the skull biomechanics and Dentistry study. The keywords of the selected original research articles were: Finite element analysis, biomechanics, skull, Dentistry, teeth, and implant. The literature review was performed in the databases, PUBMED, MEDLINE and SCOPUS. The selected books and articles were between the years 1928 and 2010. The FEA is an assessment tool whose application in different areas of the Dentistry has gradually increased over the past 10 years, but its application in the analysis of the skull biomechanics is scarce. The main advantages of the FEA are the realistic mode of approach and the possibility of results being based on analysis of only one model. On the other hand, the main limitation of the FEA studies is the lack of anatomical details in the modeling phase of the craniofacial structures and the lack of information about the material properties. [ABSTRACT FROM AUTHOR]

Introduction and objective: The placement of short dental implants is used as an alternative treatment modality to bone grafting procedures. The aim of this study was to discuss, through a literature review, the features, indications and biomechanical aspects of short implants, as well as to report the clinical factors that influence on their indication. Literature review and conclusion: It was found that short implants osseointegration can be compromised by risk factors that must be controlled to achieve treatment success. In conclusion, the main indication of short implants is to avoid an invasive surgery at atrophic areas of maxilla and mandible. Furthermore, implant design associated with surface treatment are factors that compensate its short length. [ABSTRACT FROM AUTHOR]