Abstract The main objective of this study was to cause bisphosphonate-related osteonecrosis of the jaws to develop in a rodent model. Adult male Holtzman rats were assigned to one of two experimental groups to receive alendronate (AL; 1 mg/kg/week; n = 6) or saline solution (CTL; n = 6). After 60 days of drug therapy, all animals were subjected to first lower molar extraction, and 28 days later, animals were euthanized. All rats treated with alendronate developed osteonecrosis, presenting as ulcers and necrotic bone, associated with a significant infection process, especially at the inter-alveolar septum area and crestal regions. The degree of vascularization, the levels of C-telopeptide cross-linked collagen type I and bone-specific alkaline phosphatase, as well as the bone volume were significantly reduced in these animals. Furthermore, on radiographic analysis, animals treated with alendronate presented evident sclerosis of the lamina dura of the lower first molar alveolar socket associated with decreased radiographic density in this area. These findings indicate that the protocol developed in the present study opens new perspectives and could be a good starting model for future property design.

INTRODUÇÃO: A dor é definida como uma experiência desagradável, sendo o controle da dor pós-operatória um grande desafio na área da saúde. OBJETIVO: Comparar a eficácia da dipirona e do paracetamol no controle da dor pós-operatória após exodontia de terceiros molares inclusos. MATERIAL E MÉTODO: Foram selecionados 30 pacientes da Disciplina de Cirurgia da Faculdade de Odontologia de Araçatuba - UNESP, que necessitavam extrair os terceiros molares inclusos. Desses, 15 receberam dipirona (Grupo I) e outros 15 receberam paracetamol (Grupo II) no pós-operatório. Todos os pacientes foram tratados, no pré-operatório, uma hora antes do procedimento cirúrgico, com dexametasona 4 mg e amoxicilina 1 grama. A intensidade da dor foi avaliada pelos pacientes por meio de escala visual analógica, em um período pós-operatório de 48 horas, em intervalos de 6 horas. Os critérios de exclusão foram: presença de desordens sistêmicas, hipersensibilidade medicamentosa, gestação, lactação e contraindicações locais. Os escores obtidos foram submetidos ao teste de Mann-Whitney (α = 0,05) para comparação das intensidades de dor em intervalos de 6 horas, nas 24 horas iniciais, nas 24 horas finais e no período total de 48 horas. RESULTADO: Não houve diferença estatística entre os analgésicos estudados nos intervalos de 6 horas; entretanto, nas 24 horas finais e nas 48 horas totais de observação, o Grupo I apresentou valores médios menores, estatisticamente significantes, quando comparado ao Grupo II. CONCLUSÃO: A eficácia analgésica da dipirona foi superior à do paracetamol.

INTRODUCTION: The pain is defined as an unpleasant experience, and control of postoperative pain a great challenge in healthcare. OBJECTIVE: To compare the efficacy of Dipyrone and acetaminophen in postoperative pain after third molar surgery. MATERIAL AND METHOD: Thirty patients of the Discipline of Surgery of School of Dentistry of Araçatuba - UNESP, that needed to extract their third included molars, were selected. Among these, 15 received Dipyrone (group I) and the other received acetaminophen (group II) in the postoperative. All patients were treated pre-operatively with dexamethasone 4 mg and amoxycillin 1 g, one hour before surgery. Pain intensity was evaluated by a visual analogue scale by forty eight hours postoperative period and in intervals of six hours. The exclusion criteria were: presence of systemic disorders, drugs hypersensitivity, pregnant, lactic and local contraindications. The scores obtained were submitted to the Mann-Whitney test (p < 0,05) for comparison of the pain intensity in the 6 hours intervals, in the initial 24 hours, in the last 24 hours and in the total period of 48 hours. RESULT: There was no statistical difference among the analgesics in the 6 hours intervals, however, in the last 24 hours and in the total period of 48 hours, the group I presented smaller medium values, significant statistically, when compared to group II. CONCLUSION: The analgesic efficacy of dipyrone was superior to paracetamol.

OBJECTIVE: The purpose of this study was to perform histological and histometric analyses of the repair process of autogenous bone grafts fixed at rat calvaria with ethyl-cyanoacrylate adhesive. MATERIAL AND METHODS: Thirty-two rats were divided into two groups (n=16), Group I - Control and Group II - Adhesive. Osteotomies were made at the right parietal bone for graft obtainment using a 4-mm-diameter trephine drill. Then, the bone segments were fixed with the adhesive in the parietal region of the opposite side to the donor site. After 10 and 30 days, 8 animals of each group were euthanized and the calvarias were laboratorially processed for obtaining hematoxylin and eosin-stained slides for histological and histometric analyses. RESULTS: An intense inflammatory reaction was observed at the 10-day period. At 30 days, this reaction was less intense, despite the presence of adhesive at the recipient-site/graft interface. Graft incorporation to the recipient site was observed only at the control group, which maintained the highest graft size at 10 and 30 days. CONCLUSIONS: Although the fragment was stable, the presence of adhesive in Group II did not allow graft incorporation to the recipient site, determining a localized, discrete and persistent inflammatory reaction.

From a biological standpoint, the best material for reconstruction of bone defects is the autogenous bone graft. However, as tissue healing is affected under diabetic conditions, major changes might take place in the revascularization, incorporation, replacement and remodeling phases of the grafted area. The purpose of this study was to assess the bone healing process in surgical wounds prepared in tibiae of diabetic rats and filled with autogenous bone. Forty male rats (Rattus norvegicus albinus, Wistar) were randomly assigned to receive an endovenous injection (penile vein) of either citrate buffer solution (Group 1 - control; n=20) or streptozotocin dissolved in citrate buffer solution (35 mg/kg) to induce diabetes (Group 2 - diabetic; n=20). After determination of glycemia, the animals were anesthetized and the anterolateral regions of the tibiae of both limbs were shaved, antisepsis was performed and longitudinal incisions were made in each limb. The tibiae were exposed and two 2mm-diameter surgical cavities were prepared: one in the right limb, filled with particulate autogenous bone and the other in the left limb, filled with blood clot. The animals were euthanized at 10 and 30 postoperative days. The anatomic pieces were obtained, submitted to laboratory processing and sections were stained by hematoxylin and eosin and Masson's Trichrome for histomorphologic and histometric analyses. In both groups, the wounds filled with autogenous bone graft showed better results than those filled with blood clot. The control group showed higher new bone formation in wounds filled with autogenous bone graft at 30 days than the diabetic group, but without statistical significance. It may be concluded that, in general, the new bone formation occurred with autogenous graft was quantitatively similar between control and diabetic groups and qualitatively better in the control group.