ABSTRACT
Objective: The aim of this study was to evaluate the effectiveness of platelet rich plasma with and without autogenous bone graft in the bone repair of surgical defects in rabbit tibias. Material and Methods: In this research, 25 adult male rabbits were used. Two defects have been performed in each tibia, divided into four groups: control (C = defect naturally left to heal by clot formation), autogenous (A = bone defect + autogenous graft), PRP (PRP = bone defect + PRP) and autogenous + PRP (PRPA = bone defect + autogenous graft + PRP). All the defects were covered with a dPTFE membrane. Five other animals were sacrificed at 15, 30, and 60-day postoperatively. The pieces containing the defects were processed for histological and histomorphometric analysis. Other five animals were sacrificed after 30 and 60 days and submitted to biomechanical analysis, and all the specimens were sent to the radiographic evaluation of optical density. Results: The biomechanical, radiographic, and histomorphometric results showed larger resistance, optical density, and improving bone formation in the groups A and PRPA when compared with the groups C and PRP. Conclusion: This study showed there was not an improvement in the radiographic, mechanical, and bone formation parameters when PRP was used individually or associated to the autogenous bone graft...
Objetivo: O propósito deste trabalho foi avaliar o efeito do plasma rico em plaquetas associados ou não ao enxerto ósseo autógeno no processo de reparação óssea em defeitos cirúrgicos confeccionados na tíbia de coelhos. Material e Métodos: Nesta pesquisa foram utilizados 25 coelhos adultos, nos quais foram realizados 2 defeitos em cada tíbia, divididos nos seguintes grupos de acordo com o tratamento: controle (C - defeito preenchido somente por coágulo sangüíneo), autógeno (A - defeito + enxerto), PRP (PRP = defeito + PRP) e autógeno + PRP (PRPA - defeito + enxerto + PRP). Todos os defeitos foram recobertos com uma barreira de PTFE e decorridos 15, 30 e 60 dias, 5 animais foram sacrificados por período, sendo as peças contendo os defeitos processadas para análises histológica e histomorfométrica. Outros 5 animais foram sacrificados aos 30 e 60 dias e submetidos à análise das propriedades biomecânicas e todos os espécimes foram submetidos ao exame radiográfico para análise da densidade óptica. Resutados: Os resultados biomecânicos, radiográficos e histomorfométricos mostraram maior resistência, densidade óptica e maior formação óssea nos grupos A e PRPA quando comparados com os grupos C e PRP. Conclusão: Os resultados obtidos possibilitaram concluir que não houve uma melhora nos parâmetros radiográficos, mecânicos e na neoformação óssea quando o PRP foi usado isoladamente ou associado ao enxerto ósseo autógeno...
Subject(s)
Animals , Rabbits , Bone Regeneration , Bone Transplantation , Membranes , Platelet-Rich Plasma , PolytetrafluoroethyleneABSTRACT
The author attempted to discover a method for performing delayed suture adjustment to investigate whether it actually provides more relable and stable results. In order to prevent the fromation of postoperative adhesions and delay the time of adjustment, the author used 0.1mm-thick polyteetraful-oroethylene(PTFE) as a physical barrier. PTFE was placed between the free muscle end and the sclera in 60 strabismic patients during adjustable strabismus surgery. Adjustment was not necessary in eight patients until PTFE removal. In thirteen patients, adjustment was not necessayr after first adjustment until two weeks postoperatively. PTFE was effective in delaying the adjustment after two weeks postoperatively in the remaining 39 patients. To my knowledge, this study represents the longest delayed adjustment in humans. In conclusion, PTFE can be clinically beneficial for delaying the timing of adjustment in strabismus surgery.
Subject(s)
Humans , Polytetrafluoroethylene , Sclera , Strabismus , SuturesABSTRACT
Recently, the authors had an opportunity to treat a 73-year-old male patient who was transferred to our institution with problematic multiple strictures of the anterior urethra subsequent to a suprapubic cystostomy. A proximal urethra was reconstructed with scrotal skin, but due to the shortage of distal skin, as a last resort we reconstructed a distal urethra using a polytetrafluoroethylene graft in place of 10 cm long urethral strictures. About 5 months after surgery, we had to reexplore the polytetrafluoroethylene graft area because of pain and found, much to our surprise, that the urethra had been completely regenerated around the length of polytetrafluoroethylene graft which now remained freely detached in the urethral canal. Following removal of the polytetrafluoroethylene graft, the patient could urinate normally and was subsequently discharged without further problems. We concluded that this case was incidentally successful with good regeneration of urethral mucosa of the anterior urethra by grafting a polytetrafluoroethylene tube.