Résumé
Sealing occlusal pits and fissures with resin-based sealants is a proven method of preventing occlusal caries. Retention of the sealant is very essential for its efficiency. This study evaluated the retention of glass ionomer used as a fissure sealant when compared to a self-cure resin-based sealant. One hundred and seven children between the ages of 6-9 years, with all four newly erupted permanent first molars were selected. Two permanent first molars on one side of the mouth were sealed with Delton, a resin-based sealant, and the contralateral two permanent first molars were sealed with Fuji VII glass ionomer cement. Evaluation of sealant retention was performed at regular intervals over 12 months, using Simonsen's criteria. At the end of the study period, the retention of the resin sealant was seen to be superior to that of the glass ionomer sealant.
Sujets)
Mordançage à l'acide/méthodes , Méthacrylate bisphénol A-glycidyl/usage thérapeutique , Enfant , Collage dentaire , Caries dentaires/prévention et contrôle , Émail dentaire/anatomie et histologie , Études de suivi , Ciment ionomère au verre/usage thérapeutique , Humains , Mandibule , Test de matériaux , Maxillaire , Molaire/anatomie et histologie , Scellants de puits et fissures/usage thérapeutique , Céments résine/usage thérapeutiqueRésumé
The purpose of this present study was to determine the pH changes of five different commercially available calcium hydroxide liners and variations of pH at different time intervals. The following commercially available materials were investigated: Dycal (LD Caulk); Calcimol (Vocco Products); calcium hydroxide powder (Deepti Products); Calcimol LC (Vocco Products); Lime-Lite (Pulpdent Corporation). Five samples were prepared from each liner. The pH measurements were recorded at time intervals of 1 h, 24 h, 3 days and 7 days after mixing of the liner. The pH variations of each material at the given time intervals were recorded and the means were calculated. Comparison of the mean values at all time intervals with the statistical analysis showed significantly high differences (P < 0.001) between pH values induced by each material at all time intervals. Among the water-insoluble products, Dycal had the strongest alkaline effect after 7 days interval. The materials that chemically hardened produced higher pH values than materials that hardened by a visible light source after 7 days.
Sujets)
Analyse de variance , Hydroxyde de calcium/composition chimique , Isolation de cavité dentaire , Dentine secondaire/métabolisme , Concentration en ions d'hydrogène , Statistique non paramétrique , Reminéralisation des dentsRésumé
To compare the accuracy of root canal lengths in primary teeth determined by tactile sense, electronic apex locator, conventional radiography, and digital radiography in primary teeth. The study sample consisted of twenty 20 extracted, single-rooted primary teeth. A comparison was made between the working length measurements obtained by tactile sensation, electronic apex locator, conventional film, and digital radiography, using stereomicroscopic measurements to obtain real canal length. The mean readings obtained were 15.91 +/- 2.06 by tactile measurement, 15.94 94 +/- 1.42 by apex locator, 16.06 +/- 1.73 by conventional radiography, and 15.91 +/- 1.60 by digital radiography. No statistically significant differences were seen between the techniques.