RESUMO
The purpose of the present study was to investigate the scanning electron microscopic texture of enamel and dentin cavity surfaces in extracted human teeth following different etching modalities, specifically combinations of etchants adapted to the tissue composition of the cavity walls. It was concluded that an etching technique that combined the action of 2 different etchants--ethylenediaminetetraacetic acid (EDTA) on dentin and phosphoric acid on enamel--optimized retention structures on each tissue surface of a dental cavity better than either 1 of the 2 etchants that were applied to both types of tissue in the cavity walls.
Assuntos
Condicionamento Ácido do Dente/métodos , Esmalte Dentário/efeitos dos fármacos , Dentina/efeitos dos fármacos , Adulto , Colágeno/química , Esmalte Dentário/ultraestrutura , Dentina/química , Dentina/ultraestrutura , Ácido Edético/farmacologia , Humanos , Microscopia Eletrônica de Varredura , Pessoa de Meia-Idade , Ácidos Fosfóricos/farmacologia , Camada de EsfregaçoRESUMO
The purpose of the present study was (1) to examine smear layer formation following different root planing modalities, and (2) to evaluate its removal and the exposure of collagen using an ethylenediaminetetraacetic acid gel preparation. Twenty-four periodontitis-affected human teeth were mechanically root planed. Twelve teeth were etched with an ethylenediaminetetraacetic acid gel preparation. The surfaces were examined by a scanning electron microscope. The results showed that root planing resulted in a smear layer covering the root surfaces, irrespective of treatment modality. The smear layer could be efficiently removed with the ethylenediaminetetraacetic acid gel preparation. During this process, collagen fibers were exposed to varying degrees.
Assuntos
Ácido Edético/farmacologia , Aplainamento Radicular/métodos , Camada de Esfregaço , Condicionamento Ácido do Dente , Colágeno/efeitos dos fármacos , Colágeno/ultraestrutura , Avaliação Pré-Clínica de Medicamentos , Ácido Edético/uso terapêutico , Géis , Humanos , Técnicas In Vitro , Microscopia Eletrônica de Varredura , Periodontite/patologia , Periodontite/terapia , Distribuição Aleatória , Propriedades de Superfície , Raiz Dentária/efeitos dos fármacos , Raiz Dentária/ultraestrutura , Terapia por UltrassomRESUMO
Low pH aqueous solutions of citric acid have been used in surgical periodontal therapy mainly for two reasons. It dissolves smear after a relatively short exposure time and it has been claimed to selectively remove root surface-associated mineral exposing collagen to varying degrees. The use of low pH etching agents has recently been challenged in both experimental in vitro and in vivo studies based on their necrotizing effect on the surrounding periodontal tissues. The purpose of the present study was to assess the efficacy of subgingival application of an EDTA gel preparation in removing smear and exposing collagen fibers in root surfaces following non-surgical periodontal therapy. Root surfaces which were root planed did not reveal any patent dentinal tubuli or collagen fibers. This was in contrast to the findings seen after root planing followed by etching, where intertubular surfaces were covered by a dense fibrillar network extending into patent dentinal tubuli. In high magnification these intertubular fibers displayed the cross-striated texture typical for collagen fibers. Etching of root planed surfaces with EDTA may thus enhance the effect of non-surgical root debridement in the same way as has been shown during experimental surgical procedures.
