Objective:The aim of this in vitro study was to evaluate and compare the effect of 10% sodium ascorbate, 6.5% proanthocyanidin, and 5% lycopene on the bond strength of composite resin to bleached enamel.Materials and Methods:Labial enamel surfaces of 100 extracted human maxillary central incisors were used in this study. Twenty teeth served as group I (control) and received no bleaching treatment. The remaining 80 teeth were randomly divided into four groups of 20 teeth each, based on the antioxidant used as follows: group II- bleaching with 35% carbamide peroxide gel for 30 min without the use of an antioxidant, group III- bleaching followed by use of 10% sodium ascorbate solution, group IV- bleaching followed by use of 6.5% proanthocyanidin, and group V- bleaching followed by use of 5% lycopene. These groups were further subdivided into two subgroups of 10 teeth each, based on whether composite buildup was done immediately (subgroup A) or after a delay of 2 weeks (subgroup B) post bleaching. Shear bond strength of the specimens was tested under universal testing machine. The data were tabulated and statistically analyzed.Results:Significantly higher shear bond strength values were observed in teeth treated with control group prior to bonding, followed by sodium ascorbate group.Conclusion:Within the limitations of this study, it can be concluded all the antioxidants used in this study increased the bond strength of bleached enamel. Among the antioxidant groups, sodium ascorbate showed significantly higher bond strength compared to proanthocyanidin and lycopene.
Introduction: The search to replace the chemical bleaching agent namely the Hydrogen Peroxide (HP) with a natural substance to whiten the discoloured tooth is a need of the hour, due to the severe roughing and compromised bonding of resin composite to enamel surface by this agent. Aim: To evaluate and compare the colour and surface changes in enamel surface, and the micro-shear bond strength of resin composite to enamel following bleaching with 35% HP and 2% Strawberry Extract (SE). Materials and Methods: In this in-vitro study, 30 bovine maxillary central incisors were decoronated and allocated randomly to two groups: group 1 (negative control) (n=15) and group 2 (experimental) (n=15). To evaluate the bleaching efficacy, group 2 specimens were experimentally stained with tea. Baseline colour coordinates (pre-bleach values) (L*, a*, b*) (∆E) were recorded. The crowns were sectioned to obtain four equal parts to obtain 60 specimens and these were allotted randomly to 4 subgroups a, b, c, d (n=15 each) based on the bleaching protocol. Subgroup a, Hydrogen Peroxide (HP). subgroup b, Strawberry Extract (SE); subgroup c, HP+SE (HPS); subgroup d, HP/P (HP/ Proanthocyanidin). Following bleaching, colour coordinates (post-bleach values) (L*, a*, b*) (∆E) were measured as mentioned before. Qualitative analysis of the surface (n=2) for each group was performed using scanning electron microscopy. Micro-shear bond strength of resin composite to the treated specimens (n=13) was determined using universal testing machine at a crosshead speed of 1 mm/min. Kruskal-Wallis one-way Analysis of Variance (ANOVA) was used to calculate the p-value and Post-Hoc Tukey Honest significant Test (HSD) was used to identify the significant groups, p-value (<0.05). Results: All the post-bleach specimens showed significantly higher mean ∆E (more whiter) values compared to their respective pre-bleach specimens (baseline values) (p-value -<0.05). Among the post-bleach groups, highest ∆E values (more whiter) were observed in subgroup 2c(HPS) (p-value=0.029). Similarly minimal morphological surface irregularities were observed in HPS. Group 1 (negative control) had the highest micro-shear bond strength compared to the experimental groups (group 2). Significantly, higher micro-shear bond strength was observed in subgroups 2b,c,d (SE, HPS, HPP) compared to subgroup 2a(HP) (p-value <0.001). Conclusion: SE alone or in combination with HP is an efficient and effective dental bleaching agent.
This case report aims to assess the healing of a large periapical lesion non-surgically using Calcium hydroxide (CH) with the aid of Cone Beam Computed Tomography (CBCT). A 28-year-old female patient presented with pain and swelling in the lower anterior teeth (31, 32, 41, 42) (Federation Dentaire Internationale (FDI) tooth notation system). Patient history and pre-operative radiographic examination revealed incomplete root canal treatment in relation to 31, 32, 41, 42 with periapical abscess. During the first visit, the access cavity was modified, followed by determination of the working length and biomechanical preparation. In the present case report, (CH) intracanal medicament(ICM) was placed in the canals for 2 weeks, and the process was repeated until the canals were dry. Once the canals were dry and the teeth became asymptomatic, obturation was performed. Permanent coronal seal was provided using composite restorative material. One year periodic follow-up was carried out to assess the healing of the periapical lesion, following which, post-operative healing was assessed with the help of CBCT- Periapical Index (CBCT-PAI) and was compared with the pre-operative CBCT-PAI. Regression of the lesion and formation of the trabecular pattern of the bone were noted. Intracanal medication with calcium hydroxide complemented the instrumentation with irrigation and optimal disinfection of the root canal system. In this case report, the use of CBCT as a diagnostic tool helped in the accurate measurement of periapical lesion size.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.