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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.

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PURPOSE: Extensive bone defects in maxillofacial region can be corrected with autograft. However the disadvantages of this type of therapy lead to the search for new bone substitutes. Thus, we evaluated the biological behavior and osteoinductive platelet-derived growth factor type BB (PDGF-BB) associated with different carriers, by histological analysis and immunohistochemical histometric critical defects performed in rat calvaria. MATERIALS AND METHODS: Critical defects were created with 5-mm diameter calvaria of rats. Each defect was randomly divided into 8 experimental groups, evaluated at 15 and 30 postoperative days for histomorphometry and immunohistochemistry. RESULTS: The results showed new bone formation in all groups, independent of postoperative time. At 30 days, the beta-tricalcium phosphate matrix (TCP) group just did not differ from bone matrix mineralized bovine (BIO) group in the new bone formation (P = 0.1403). In none of the groups' analyzed biomaterials, growth factor stimulated increase in bone formation (P > 0.05). CONCLUSION: With the methodology used, the growth factor associated with the tested biomaterials did not induce new bone formation.

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PURPOSE: The installation of implants has become a routine procedure in the clinic. However, it takes time and adequate bone thickness, and for that, tissue engineering has made efforts to develop substitutes for autografts, in view of certain disadvantages of this material. The decision to choose the most suitable graft material for each case is an important step in the success of bone reconstruction. This study was to verify, by means of immunohistochemical study, that the addition of bone morphogenetic protein had some influence on biomaterials commercially available, taking into account the formation of mineralized tissue, bone replacement, and the amount of degradation of biomaterials. METHODS: The sample consisted of 72 rats that were divided into eight treatment groups, in which two defects of 5 mm were made in each animal calvaria. Euthanasia was performed at 5, 15, and 30 days postop. RESULTS: A histologic and histometric analysis was performed to quantitate the area of mineralized tissue formed, the area of newly formed bone, and the area of degradation of the biomaterials. Data were analyzed with multiple comparisons of means by Tukey contrasts, and significant difference was assigned at the level of P < 0.05. The proteins used for immunohistochemical analysis accounted for the process of formation, mineralization, and bone resorption and was performed using ordinal qualitative analysis, where from assigning scores. CONCLUSIONS: Bone morphogenetic protein 2 was shown to be effective as an inducer of bone formation process independent biomaterial used mainly for accelerating the resorption process of the framework.

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This study aimed to assess the biological response of BMP-2 (bone morphogenetic protein-2) in supplementation with ß-tricalcium phosphate (TCP) as a carrier in the bone healing of surgical defects in rats' calvaria. A critical-size defect (5mm in diameter) was filled with ß-TCP alone or added with that plus 5mg of BMP-2 at 5, 15, and 30 postoperative days. Histomorphometric and immunohistochemical (osteocalcin, collagen type I, and metalloproteinase-9) analysis was performed to assess the features of bone healing. Histological behavior and collagen type I labeling showed increased formation of the collagen matrix, leading to a higher percentage of newly formed bone and biomaterial for tissue and more total mineralization of pure TCP when compared to the other groups. The supplementation with BMP-2 promoted faster TCP remodeling; however, there was no statistically significant difference for the bone formed in both groups (P>0.05). Collagen-matrix formation and new bone formation reached maximum levels when the defects were filled with pure TCP, even exceeding the levels from BMP-2 supplementation.

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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.

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PURPOSE: We sought to evaluate the effectiveness of bone substitutes in circumferential peri-implant defects created in the rabbit tibia. METHODS: Thirty rabbits received 45 implants in their left and right tibia. A circumferential bone defect (6.1 mm in diameter/4 mm depth) was created in each rabbit tibia using a trephine bur. A dental implant (4.1 mm × 8.5 mm) was installed after the creation of the defect, providing a 2-mm gap. The bone defect gaps between the implant and the bone were randomly filled according to the following groups: blood clot (CO), particulate Bio-Oss(®) (BI), and Bio-Oss(®) Collagen (BC). Ten animals were euthanized after periods of 15, 30, and 60 days. Biomechanical analysis by means of the removal torque of the implants, as well as histologic and immunohistochemical analyses for protein expression of osteocalcin (OC), Runx2, OPG, RANKL, and TRAP were evaluated. RESULTS: For biomechanics, BC showed a better biological response (61.00±15.28 Ncm) than CO (31.60±14.38 Ncm) at 30 days. Immunohistochemical analysis showed significantly different OC expression in CO and BC at 15 days, and also between the CO and BI groups, and between the CO and BC groups at 60 days. After 15 days, Runx2 expression was significantly different in the BI group compared to the CO and BC groups. RANKL expression was significantly different in the BI and CO groups and between the BI and BC groups at 15 days, and also between the BI and CO groups at 60 days. OPG expression was significantly higher at 60 days postoperatively in the BI group than the CO group. CONCLUSIONS: Collectively, our data indicate that, compared to CO and BI, BC offered better bone healing, which was characterized by greater RUNX2, OC, and OPG immunolabeling, and required greater reversal torque for implant removal. Indeed, along with BI, BC presents promising biomechanical and biological properties supporting its possible use in osteoconductive grafts for filling peri-implant gaps.

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The placement of dental implants and subsequent placement of immediate temporary dentures after extractions has become a treatment modality accepted by the scientific community. In addition to the functional factor, the surgical procedure in a single stage in the anterior region of the maxilla offers an esthetic appearance, and relieves the psychological concerns of patients. To guarantee the success and longevity of treatments performed, the fabrication of surgical guides is a helpful method in these situations. Guided surgery has gained attention because it restores esthetics with immediate restoration, provides the patient with comfort in addition to dispensing with the need for performing surgical flaps. This auxiliary method allows the position and design of the implant, as well as the perforation sequence to be programmed, thus optimizing the clinical results. In this study, the authors present a clinical case of a patient who was submitted to extraction and subsequent implant placement with immediate loading in the anterior region of the maxilla, performed in a satisfactory manner.

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Defeitos mucogengivais em decorrência do avanço da doença periodontal resultam em perda óssea alveolar e consequente migração apical da papila interdental, levando à formação de triângulos negros que comprometem a estética do paciente. O tratamento de defeitos mucogengivais e peri-implantares vem sendo amplamente estudado no sentido de otimizar os resultados clínicos alcançados e são considerados um grande desafio na prática clínica. Assim, o presente estudo buscou avaliar a eficácia clínica de um novo método para eliminar ou reduzir pequenos defeitos de papila, utilizando-se o gel de ácido hialurônico (AH). A utilização de gel de AH, comercialmente disponível, foi utilizado em dois casos clínicos como um método possível de formação de papila entre implantes, e em áreas de pôntico de prótese fixa sobre implantes em regiões estéticas da maxila. Os pacientes incluídos neste estudo apresentavam- -se com pelo menos um defeito de papila na região anterior. Antes do tratamento, fotografias da condição inicial dos pacientes foram obtidas. O procedimento clínico para aplicação do gel de AH (0,2 mL) foi realizado com anestesia tópica, após profilaxia, utilizando-se um dispositivo apropriado, 2-3 mm apical à borda coronária da papila envolvida. Reavaliações periódicas a cada 3 semanas foram conduzidas, e a aplicação do gel de AH foi repetida por três vezes. Os pacientes foram acompanhados durante um período de seis meses após a aplicação do gel e fotografias foram obtidas para comparação dos resultados alcançados. Os resultados mostraram satisfatório aumento do volume tecidual nos dois casos tratados, os quais resultaram em um maior preenchimento tecidual e consequente melhora das condições estéticas dos pacientes. Em conclusão, os resultados do presente estudo são encorajadores, evidenciando que pequenos defeitos de papila interdentária entre pônticos e entre implantes podem ser solucionados por meio da aplicação clínica do gel de AH, resultando em satisfatório ganho tecidual com baixa morbidade ao paciente (AU)

Mucogingival defects as a consequence of the advancement of periodontal disease result in bone loss and subsequent apical migration of the interdental papilla, leading to the formation of black triangles that compromise the patient aesthetics. The treatment of mucogingival and peri-implant defects is considered a major challenge in clinical practice and has been widely studied in order to optimize clinical results. Thus, the present study sought to evaluate the clinical effectiveness of a new method to eliminate or reduce small papillary defects, using the hyaluronic acid gel (HA). The HA gel, commercially available, was used in two cases as a possible method for the formation of papilla between implants and in pontics region of implant-supported prostheses in the anterior maxillary region. The patients included in this study had at least one papillary defect in the anterior region. Before treatment, photographs of the initial condition of all patients were obtained. The clinical procedure for the application of the HA gel (0.2 mL) was performed under topic anesthesia, after dental prophylaxis, using an appropriate device, 2-3 mm apical to the coronal tip of the involved papilla. Patients were seen every 3 weeks, and the application of the HA gel was repeated three times. Patients were followed for a period of six months after the HA gel application and photographs were taken for results comparison. Satisfactory increased tissue volume was observed in all cases, which resulted in greater tissue filling and consequent improvement of aesthetic conditions. In conclusion, the results of the present study are encouraging, showing that small defects of interdental papilla between implants and prosthetic pontic can be solved through clinical application of HA gel resulting in satisfactory tissue gain with low morbidity to the patient (AU)

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O traumatismo dentário desperta atenção na Odontologia, devido ao comprometimento estético e funcional que ocasiona. Dentre os traumas, a avulsão é uma das principais questões por ser uma lesão grave e envolver danos complexos ao ligamento periodontal. O tratamento de escolha é o reimplante dentário. O objetivo deste estudo foi apresentar a abordagem do trauma dental em um paciente que sofreu avulsão dos dentes 11 e 21. Os elementos foram reimplantados duas horas após o trauma, caracterizando o caso como reimplante tardio. Foi realizada endodontia de ambos os dentes e, após 12 anos de acompanhamentos clínico e radiográfico, houve necessidade de extração dos elementos 11 e 21 devido à presença de grandes áreas de reabsorção por substituição na porção radicular. Implantes osseointegráveis foram instalados na mesma sessão, a fim de reabilitar o paciente que nesse momento apresentava maturidade óssea, estando apto a receber o implante. O caso se encontra com quatro anos de acompanhamento e nenhuma sintomatologia clínica foi observada. Frente à avulsão dentária, o reimplante ainda é a conduta ideal mesmo quando há necessidade de um futuro implante devido à ocorrência das reabsorções dentárias, pois quanto maior a permanência do dente reimplantado no alvéolo, maior a preservação do osso alveolar que mantém sua forma e espessura, favorecendo assim também a estética e pela possibilidade de postergar as cirurgias para colocação dos implantes.

Tooth trauma demands attention in Dentistry due to its esthetic and functional impairments. Avulsion is one of the main issues regarding its severity and complex damage to the periodontal ligament. The treatment of choice is reimplantation. The aim of this article is to present an approach to avulsed teeth 11 and 21. Both elements were reinserted 2 hours later, which characterizes a delayed reimplantation. After endodontic treatment, as well as 12 years of clinical and radiographic follow-up, those teeth were extracted due to large root resorption areas. Dental implants were installed in the same session but now the patient presented with excellent bone maturity to receive the implants. This case now has 4 years of follow-up and no clinical symptomatology was reported. In case of tooth avulsion, the reimplantation is the ideal option aiming for further implant placement due to tooth resorption, because the longer a tooth can be kept in its alveolar socket, the more the bone contour and width preservation are seen, also favoring esthetics and postponing of dental implant surgeries.

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Este trabalho relata um caso clínico onde uma paciente de 82 anos de idade queixava-se da instabilidade da porção removível de sua prótese maxilar híbrida. Dois implantes foram colocados na região posterior e a nova prótese passou a funcionar como uma overdenture retida por encaixes tipo O-ring. As extremidades distais dos encaixes nas coroas metalocerâmicas dos dentes 13 e 23 não puderam ser capturadas. Mesmo em função das limitações técnicas e econômicas, o tratamento proposto satisfez as exigências estéticas e funcionais da paciente.

This work reports a clinical case where a 82 years-old patient had complaints about the removable portion of an hybrid maxillary prosthesis. Two dental implants were inserted in the posterior region and the new reconstruction was designed as an O-ring retained overdenture. The female portions of the metalloceramic crowns of teeth 13 and 23 could not be captured in this way. Even thus, given the technical and financial limitations, the proposed treatment addressed all esthetic and functional patient demands

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