{"title":"Adaptation of composite fillings to cavity walls in three different cavities.","authors":"Y Katoh, K Shinkai","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Adaptation of eight kinds of resin restorations on Class V enamel cavity, cement-enamel-junction (CEJ) cavity and root surface cavity were compared. Extracted human premolars were used as experimental specimens. Restored specimens were divided into two groups; short storage group of 2 week duration and long storage group of 6 month duration. The specimens were thermal cycled during storage. After that replicas of the vertical sections were made for examination by SEM and the gaps measured from photographs. The appearance and width of gaps between resin and cavity walls were characterised by the type of cavity and the filling materials. In Class V enamel cavity, gaps were observed on the cavity floor, whilst almost none was observed in other areas showing good adaptation. In the CEJ cavity, gaps appeared only at the cavity floor and gingival wall. In the root surface cavity, gaps were observed on all cavity walls with smaller widths on the occlusal wall and greater width on the cavity floor. Clearfil-F and Clearfil-F II showed fine adaptation on all cavities in general, especially on the dentinal cavity wall. Almost all the materials showed a tendency to form gaps which was found to increase with time. The difference in width, however, varied with the materials used.</p>","PeriodicalId":79392,"journal":{"name":"Asian journal of aesthetic dentistry","volume":"1 1","pages":"3-11"},"PeriodicalIF":0.0,"publicationDate":"1993-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"19140735","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
T Nakamura, H Nakajima, P Salimee, T Hino, T Maruyama
{"title":"Effect of bleaching on vital discoloured teeth--a colorimetric evaluation in three patients.","authors":"T Nakamura, H Nakajima, P Salimee, T Hino, T Maruyama","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Vital bleaching is considered effective for reduction of tooth discolouration. This evaluation was to measure colour changes before and after bleaching of vital tetracycline-discoloured teeth in three patients. Vital bleaching of their anterior maxillary teeth was performed five times at weekly intervals. Tooth colour was measured with a small-area colorimeter before, immediately and two, four and six months after bleaching. The results were expressed in the CIE L*a*b* colour system. The L* value, a lightness variable, increased after bleaching. The a* value changed only negligibly, but the b* value decreased after bleaching showing changes in the tooth colour from yellow to blue. The colour differences before treatment and six months after bleaching was visually perceivable.</p>","PeriodicalId":79392,"journal":{"name":"Asian journal of aesthetic dentistry","volume":"1 1","pages":"25-8"},"PeriodicalIF":0.0,"publicationDate":"1993-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"19140733","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"SEM analyses of repaired glass-ionomer cements.","authors":"A Jamaluddin, G J Pearson","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>This study assessed the nature of the adhesion in repaired glass-ionomer restorative materials. Two chemically different glass-ionomer cements, Ketac Fil and Chemfil II Cap, and three different methods of conditioning the surface for repair were employed. Specimens of each material were prepared and the cut surfaces were then treated with either 35% phosphoric acid, 35% polyacrylic acid or a combination of phosphoric acid followed by polyacrylic acid. Freshly mixed material was injected against these treated surfaces and allowed to set under simulated intraoral conditions. The specimens were tested to failure in flexion after seven days storage. Assessment of the fractured surfaces was then carried out using the scanning electron microscope. The results showed the occurrence of both adhesive and cohesive failure.</p>","PeriodicalId":79392,"journal":{"name":"Asian journal of aesthetic dentistry","volume":"1 1","pages":"19-23"},"PeriodicalIF":0.0,"publicationDate":"1993-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"19140732","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}