RESUMO
Many studies have shown that alloplastic bone grafts are clinically stable and safe. Nevertheless, postoperative problems such as ankylosis and root resorption are associated with alloplastic bone grafts. This report examined two cases of ankylosis of nonresorbable hydroxyapatite (NHA) alloplastic grafts associated with recurrent periodontitis. There was no clear border between the NHA particles and dentin. The particles were irregularly shaped and had plaque on the surfaces. It is postulated that ankylosis of NHA particles and dentin is a contributing factor in recurrent periodontitis.
Assuntos
Materiais Biocompatíveis/efeitos adversos , Substitutos Ósseos/efeitos adversos , Durapatita/efeitos adversos , Periodontite/etiologia , Adulto , Idoso , Cálculos Dentários/etiologia , Placa Dentária/complicações , Dentina/patologia , Feminino , Corpos Estranhos/etiologia , Tecido de Granulação/patologia , Humanos , Masculino , Microscopia Eletrônica de Varredura , Bolsa Periodontal/etiologia , Recidiva , Mobilidade Dentária/etiologiaRESUMO
The present study was performed to evaluate the effects of calcium phosphate cement (alpha-DT cement) containing alpha-TCP, dicalcium phosphate anhydrous, and tetracalcium phosphate mixed with hydroxypropyl cellulose (HPC) for bone augmentation within a titanium cap in the rabbit calvarium. A total of 24 male adult Japanese white rabbits were used in this study. In each rabbit, one side of the cap was filled with alpha-DT cement (alpha-DT) or alpha-DT cement mixed with HPC (alpha-DTH), and the other side of the cap was left empty (control). After 1 and 3 months, newly generated tissue and mineralized bone areas were measured histomorphometrically. Significant differences in newly generated tissue and mineralized tissue were observed between the alpha-DT or alpha-DTH group and the control at 3 months. Furthermore, alpha-DTH showed significantly more mineralized tissue than alpha-DT group. Our findings indicated that although alpha-DT cement was effective for bone augmentation, alpha-DTH was more useful than alpha-DT for bone maturation.
Assuntos
Cimentos Ósseos/uso terapêutico , Doenças Ósseas/cirurgia , Regeneração Óssea/efeitos dos fármacos , Fosfatos de Cálcio/uso terapêutico , Celulose/análogos & derivados , Regeneração Tecidual Guiada/instrumentação , Crânio/cirurgia , Implantes Absorvíveis , Animais , Doenças Ósseas/patologia , Calcificação Fisiológica/efeitos dos fármacos , Celulose/uso terapêutico , Ósteon/patologia , Processamento de Imagem Assistida por Computador , Masculino , Teste de Materiais , Osteoblastos/patologia , Osteoclastos/patologia , Coelhos , Crânio/efeitos dos fármacos , Crânio/patologia , Fatores de Tempo , TitânioRESUMO
OBJECTIVES: Guided bone augmentation (GBA) in its most challenging form is the creation of new bone through the guidance of bone cells to an area beyond the original outer skeletal envelope. We used a microfocus computerized tomography (R_mCT) system to examine bone augmentation beyond the skeletal envelope in the rat calvarium. STUDY DESIGN: The calvarium was exposed and critical-size 5-mm defects were prepared bilaterally. Two resin caps were placed with or without hydroxyapatite (HA), and images of bone augmentation within the resin cap were obtained using R_mCT. RESULTS: The experimental site showed bone regeneration beyond the skeletal envelope. Bone continuity was observed between the defect edge and HA. In contrast, no new bone formation was observed beyond the skeletal envelope at the control site. The bone volume increased significantly at the experimental site compared with the control site in a time-dependent manner. CONCLUSIONS: The R_mCT system enabled the continuous observation of guided bone augmentation with graft materials in rat calvarium.
