Digital subtraction radiographic analysis of the combination of bioabsorbable membrane and bovine morphogenetic protein pool in human periodontal infrabony defects

Objectives: This study assessed the bone density gain and its relationship with the periodontal clinical parameters in a case series of a regenerative therapy procedure. Material and Methods: Using a split-mouth study design, 10 pairs of infrabony defects from 15 patients were treated with a pool of bovine bone morphogenetic proteins associated with collagen membrane (test sites) or collagen membrane only (control sites). The periodontal healing was clinically and radiographically monitored for six months. Standardized presurgical and 6-month postoperative radiographs were digitized for digital subtraction analysis, which showed relative bone density gain in both groups of 0.034 ± 0.423 and 0.105 ± 0.423 in the test and control group, respectively (p>0.05). Results: As regards the area size of bone density change, the influence of the therapy was detected in 2.5 mm2 in the test group and 2 mm2 in the control group (p>0.05). Additionally, no correlation was observed between the favorable clinical results and the bone density gain measured by digital subtraction radiography (p>0.05). Conclusions: The findings of this study suggest that the clinical benefit of the regenerative therapy observed did not come with significant bone density gains. Long-term evaluation may lead to a different conclusions

Influence of crown shape on root coverage therapy

OBJECTIVES: The aim of this study was to evaluate the influence of the crown shape on the outcomes of root coverage procedures. MATERIAL AND METHODS: Eighty patients with Miller class I gingival recessions in maxillary canines or premolars were selected. The recession areas were treated using the subepithelial connective tissue grafting. The following clinical parameters were analyzed: crown length (CL) and width (CW), recession height and width, probing depth, clinical attachment level, width and thickness of the keratinized tissue and percentage of root coverage achieved. These measurements were recorded at baseline and 6 months after the surgical procedure. The CW/CL ratio was calculated for each tooth and the median obtained (0.83). Patients were then ranked into two groups, according to the shape of the tooth with gingival recession: Group A - square crown shape (CW/CL values above 0.83) and Group B - long and narrow crown shape (CW/CL values below 0.83). RESULTS: No statistically significant differences (p>0.05) were found between groups in any of the clinical parameters at baseline. After 6 months, both groups presented improved clinical outcomes for all parameters analyzed compared to baseline (p>0.05). The mean percentages and standard deviations of root coverage achieved in Group A and Group B was 91.37 (16.75) and 85.49 (23.55), respectively (p>0.05). CONCLUSIONS: Crown shape did not influence the root coverage obtained with the subepithelial connective tissue graft technique

Osteointegração de osso bovino desvitalizado, hidroxiapatita de coral, poliuretana de mamona e enxerto autógeno em coelhos Devitalized bovine bone, porous coralline hydroxyapatite, castor beans polyurethane and autograft implants in rabbits

OBJETIVO: Estudar comparativamente implantes de osso bovino desvitalizado, hidroxiapatita porosa de coral, poliuretana de mamona e enxerto ósseo autógeno no reparo de defeito ósseo de 6x10mm em fêmur de coelhos. MÉTODOS: Noventa e seis coelhos Nova Zelândia distribuídos em 4 grupos conforme o material de preenchimento do defeito ósseo. Após seguimento de 4 e 12 semanas, as peças foram submetidas a análise macroscópica, microscópica, radiográfica, tomográfica e histométrica. Aos resultados aplicou-se testes estatísticos de Kruskal-Wallis, Mann-Whitney, Fisher, “t” de Student e quiquadrado. RESULTADOS: O enxerto ósseo autógeno mostrou maior potencial osteogênico; o osso bovino desvitalizado produz maior reação inflamatória, maior número de cavidades císticas e lentidão de integração; a hidroxiapatita porosa de coral mantém a radiodensidade inicial; os implantes de osso bovino desvitalizado e poliuretana de mamona mostraram radiodensidades aumentadas conforme foram invadidos pelo tecido ósseo neoformado. CONCLUSÃO: O implante de osso bovino desvitalizado induz reparação tecidual guiada mais lenta quando comparado ao enxerto ósseo autógeno e aos implantes de hidroxiapatita porosa de coral e poliuretana de mamona.<br>PURPOSE: To study comparatively devitalized bovine bone, porous coralline hydroxyapatite, castor beans polyurethane implants and autograft in the repair of 6x10mm bony defect in femur of rabbits. METHODS: Ninety six New Zealand rabbits were distributed in 4 groups conforms the material of replacement of the bony defect. After following of 4 and 12 weeks, the pieces were submitted the macroscopic, microscopic, radiographic, tomographic and histometric analysis. To data was applied Kruskal-Wallis, Mann-Whitney, Fisher, t-Student and qui-square statistical tests. RESULTS: The autograft showed greatest osteogenic potential; the devitalized bovine bone produces larger inflammatory reaction, larger number of cystic cavities and slowness integration; the porous coralline hydroxyapatite maintains the initial radiodensity; devitalized bovine bone and castor beans polyurethane implants showed increased radiodensities as they were invaded by the bony formation. CONCLUSION: Devitalized bovine bone implants induces slower bony formation, when compared to the autograft, porous coralline hydroxyapatite and castor beans polyurethane implants