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AIM: This study evaluated the effect of staining and subsequent bleaching on the color stability and surface roughness of three resin composites. MATERIALS AND METHODS: One hundred and eight customized plastic disks from a plastic mold with an outer diameter of 10 mm and thickness of 1.02 mm were fabricated. Samples were divided into three groups of 36 specimens each - Group I (Estelite® α - Supranano), Group II (Filtek™ Z250 XT - Nanohybrid), and Group III (Filtek™ P90-Silorane). Subsequently, baseline surface color and roughness values were tabulated using spectrophotometer and profilometer, respectively. The specimens were then subjected to staining with coffee and turmeric for a period of 3 h/day for 40 days and following this, bleaching of the samples was done using a bleaching agent carbamide peroxide gel 15% for 8 h/day for 14 consecutive days. RESULTS: Estelite® α performed better by maintaining color stability with minimal roughness compared to Filtek™ P90 and Filtek™Z250 XT. Turmeric had a greater potential to stain composites compared to coffee in all the groups.
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BACKGROUND: Dentin desensitizers may change the properties of smear layer and have adverse effects on the bonding performance of adhesive systems. AIM: The aim of this study was to compare the effect of bioactive glass (BG), hydroxyapatite, and diode laser desensitization on shear bond strength of resin composites to dentin at different time intervals. MATERIALS AND METHODS: Seventy-two caries-free maxillary premolars were selected. Buccal surfaces were flattened to expose dentin. Teeth were divided into four groups (Groups 1, 2, 3, and 4) according to treatment modality (control with no pretreatment, Sensodyne Repair and Protect, Teethmate Desensitizer, diode laser). Bonding was performed using self-etch adhesive followed by composite buildup. Universal testing machine was used to determine shear bond strengths immediately after bonding, after 3 months, and 5 months storage in artificial saliva. RESULTS: Pretreatment with BG and hydroxyapatite desensitizers increased, whereas diode laser decreased mean shear bond strength of composite to dentin as compared to control group. No statistical significant difference in shear bond strength values was seen in groups after storage. CONCLUSION: Desensitizing toothpastes incorporating remineralizing agents not only occluded open dentinal tubules but also increased shear bond strength of composite to dentin.
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BACKGROUND AND OBJECTIVES: The aim of the study was to determine the effect of two access cavity designs on the peri-cervical dentin thickness before and after instrumentation using cone beam computed tomography (CBCT). MATERIALS AND METHODS: Sixty mandibular anterior teeth were divided into two groups of thirty teeth each: Group I: conventional access cavity preparation, where access was prepared just above the cingulum and Group II: incisal access cavity preparation, where access was prepared in proximity to the incisal edge. CBCT scans were taken preoperatively, following access cavity preparation and post instrumentation. 200 µm thick slices were obtained 4mm apical and coronal to the cemento-enamel junction. The peri-cervical dentin thickness was calculated on the facial, lingual, mesial, and distal for all the three obtained scans. RESULTS: The analysis showed that access cavity preparation and instrumentation resulted in a significant loss of tooth structure in Group I on all surfaces, but in Group II, there was a significant loss of tooth structure only in the mesial, lingual, and distal surfaces (P < 0.05). CONCLUSION: Incisal access cavity preparation resulted in lesser loss of dentin in the peri-cervical region.
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BACKGROUND: Alleviating pain is of utmost importance when treating patients with endodontic pain. AIM: To compare and evaluate the efficacy of two modes of delivery of pretreatment Piroxicam (Dolonex(®), Pfizer) for the management of postendodontic pain. MATERIALS AND METHODS: Sixty-six patients with symptomatic irreversible pulpitis were randomly divided into three groups of 22 subjects Group I - control group, no pharmacological intervention, Group II - patients received pretreatment oral Piroxicam (40 mg), Group III - patients received pretreatment intraligamentary injections totaling 0.4 mL of Piroxicam. Single visit endodontic therapy was performed by a single endodontist. Visual analogue scale was used to record pain before treatment and 4, 8, 12, 24, and 48 h postoperatively. Mann-Whitney U-test and Kruskal-Wallis tests were used to analyze the data. RESULTS: The patients in Groups II and III perceived less postendodontic pain as compared to Group I (P < 0.05), at all the time intervals. At 12, 24, and 48 h, pain experience in patients of Group III was significantly less. CONCLUSIONS: Intraligamentary mode of delivery of Piroxicam was more efficacious.
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The bond strength of ActiV GP and gutta-percha/AH Plus after using 2% CHX as final rinse was evaluated in this study. According to the final irrigation regimen forty roots were divided into two groups (n = 20) randomly: Group 1-5 ml of 17% EDTA; Group 2-5 ml of 17% EDTA followed by 5 ml of 2% chlorhexidine gluconate (CHX). Based on the obturation system the two groups were further subdivided into two subgroups (n = 10). The roots were horizontally sectioned from the coronal and midthird sections for measuring the push-out bond strength. CHX/AH Plus (2.795 ± 0.42 MPa) and EDTA/ActiV GP (1.489 ± 0.117 MPa) recorded the highest and lowest mean bond strength values respectively. It was concluded that when 2% CHX was used as a final irrigation rinse the bond strength of both gutta-percha/AH Plus and ActiV GP obturation system improved significantly.
