Comparative evaluation of the fracture resistance of teeth prepared with rotary system, filled with single cone gutta-percha and laterally condensed with zinc oxide eugenol and resin based (AH26) sealers to that of Resilon.

AIM AND OBJECTIVE: To compare the fracture resistance of teeth prepared with rotary system and filled with single cone guttapercha followed by lateral condensation with different sealers like zinc oxide eugenol and resin based (AH26) to that of resilon. MATERIALS AND METHODS: A total number of 70 extracted intact human permanent maxillary incisors were selected. All prepared samples were divided into one control group (n = 10) and three experimental groups (n = 20 per group). Group 1 control. This group received no obturation; the root canal opening was sealed with a temporary filling material (Cavit, Premier Dental Products, Plymouth Meeting, PA) Group 2: Gutta-Percha and zinc oxide Eugenol sealer. Group 3: Gutta-Percha and AH26 sealer. (DiaDent, Korea) dipped in AH26 sealer. Group 4: Resilon cones and RealSeal Resin Sealer. Obturation was accomplished using a 0.06 taper size 40 gutta-percha master point. All the root samples were stored in 100% humidity at 37 °C for 2 weeks to allow the sealer to set completely. The root samples were then prepared for mechanical testing and the data was recorded and analyzed statistically. RESULTS: One-way ANOVA and Post hoc test (Duncan Multiple range test) were employed to determine possible statistical variation among the groups tested in this study. The force for group 2 was significantly greater than that for the control group 1 (no obturation).The force for group 3 was significantly greater than that for group 2. The force for group 4 was significantly greater than that for group 3. All other groupwise comparisons were not significant at 5% level. Group 4 seemed to have the greatest force among the three groups of interest in the study. CONCLUSION: Root canals filled with Resilon increased the in vitro resistance of single canal extracted teeth compared to other experimental groups. The mean fracture resistance value for the experimental groups in ascending order was as follows: Root canals instrumented but not filled, filled with gutta-percha and zinc oxide eugenol sealer, filled with gutta-percha and AH26 sealer and filled with Resilon. CLINICAL SIGNIFICANCE: Resilon is a promising material for reinforcement of endodontically treated teeth.

A comparative study of impression procedures for distal extension removable partial dentures.

AIM: This study was carried out with the purpose of comparing three impression methods as to which of them placed tissues most favorably. METHODS: The methods used were Hindels method, selective tissue placement method and functional reline method. The measurements obtained were analyzed to determine which of the three impression methods placed the mucosal tissues maximally. To compare and measure tissue placements, autopolymerizing acrylic resin platforms were constructed to the height of the occlusal surfaces of the remaining teeth. 15 orthodontic buccal tubes were placed on each side of the platform. They were arranged in three sets of five and attached to the platform over selected reference regions by means of autopolymerizing resin. The selected reference areas were in anterior, middle and posterior areas of the ridge on either side. RESULTS: No significant difference was seen in tissue placement in the anterior middle and posterior regions in each of the three methods when each method was assessed separately. Selective tissue placement method placed the tissues maximally (7.547 mm) followed by Hindels method (7.2110 mm) and the least placement was by functional reline method (5.856 mm). Tissue placement was significantly higher in Hindels method as compared to functional reline method (p < 0.001). CONCLUSION: Tissue placement was maximum in the posterior region, followed by the middle region and least in the anterior region of the mandibular ridge for all three methods. Selective tissue placement method showed the maximum overall tissue placement followed by the Hindels method and minimum placement was by functional reline method. CLINICAL SIGNIFICANCE: Selective tissue placement method provided maximum overall tissue placement and can be a preferred technique for impression making for bilateral distal extension removable partial denture fabrication.