Effect of herbal antioxidants on the shear bond strength of composite resin to bleached enamel at different time intervals.

Background: Anterior tooth discolorations can be treated conservatively and noninvasively through bleaching to achieve the desired esthetic outcomes. However, bleaching along with composite resin is advisable for certain clinical cases for optimum results. However, shear bond strength (SBS) of composite resin to the bleached tooth gets significantly lowered. Before placing the composite restoration, the bleached enamel needs to be treated with antioxidant agents to increase its SBS. The study aims to evaluate and compare the effect of herbal antioxidants on SBS of composite resin to bleached enamel at different time intervals. Materials and Methods: Sixty extracted single-rooted maxillary incisors postdecoronation, keeping their labial surfaces up were mounted in cold-cure acrylic resin. The samples were randomly divided into: Group I - unbleached; Group II - 10% pine bark extract for 10 min postbleaching; Group III - 10% pine bark extract for 20 min postbleaching; Group IV - application of 10% rosemary extract for 10 min postbleaching, Group V - application of 10% rosemary extract for 20 min postbleaching; Group VI - no application of antioxidant. 35% hydrogen peroxide was used for bleaching all the samples except those which served as negative control. Later composite cylinder 4 mm in diameter and length were built on prepared enamel. The maximum load at failure was recorded using the universal testing machine. Statistical Analysis: Data were analyzed using the analysis of variance and Tukey's t-test with significance level of P < 0.05. Results: Highest load was exhibited by Group I. Group V showed satisfactory shear strength followed by Groups IV, III, II, and VI. Conclusion: Both 10% rosemary and 10% pine bark extracts showed better results when applied for 20 min as compared to 10 min application. Increased duration of antioxidant application increases the SBS.

Assessment of the impact of XP-Endo Finisher file on push-out bond strength of various endodontic sealers.

Background: An endodontic treatment is considered a success after thorough chemomechanical debridement coupled with obturating root canals in a concrete way thereby providing hermetic seal. Gutta-percha being nonadherent necessitates use of a sealer to achieve hermetic seal. Adequate adhesion of root canal sealer with gutta-percha core and radicular dentin ensures lack of apical leakage. Materials and Methods: Sixty extracted mandibular premolars with single root canal decoronated at cementoenamel junction were selected and randomly allocated to two groups (n = 30). Samples in Group 1 were prepared with BT Race file, while Group 2 samples were prepared with BT Race alongwith XP Endo file. Absorbent paper points were used for canal drying and samples were randomly divided into six subgroups. In Subgroup I, obturation was done with bio-ceramic (BC) sealer (Endosequence BC) and BC gutta-percha. In Subgroup II, resin-based (AH plus) sealer and gutta-percha were used. In Subgroup III, calcium hydroxide-based (Sealapex) sealer and gutta-percha were used. Sectioning of root samples was done perpendicularly into coronal, middle, and apical segments of 3 mm each. A universal testing machine was used for sample testing, in which push-out bond strength corresponded to the highest value obtained. Stereomicroscopic (×20) study of the samples determined the failure mode at dentin/sealer/main cone interface. Statistical Analysis: Analysis of variance and post hoc Tukey's tests were used for data analysis. Results: Endosequence BC with XP-Endo files showed the highest mean push-out bond strength (16.31 MPa), whereas Sealapex without XP-Endo file had the lowest values (12.76 MPa). Mixed failure of adhesive and cohesive mode was observed for most samples. Conclusion: Adjunctive irrigation agitation technique utilizing XP-Endo Finisher facilitates biofilm eradication from difficult niches in root canals, thereby improving adhesion of sealer and subsequently the sealer bond strength.

Comparative evaluation of marginal adaptation of mineral trioxide aggregate, Biodentine, and geristore as a root end filling material: An in vitro scanning electron microscope study.

Aim: The aim of this in vitro study was to measure the quality of marginal adaptation of three root end filling materials by scanning electron microscope (SEM). Methodology: Thirty extracted human permanent single-rooted single canal maxillary anterior teeth with mature apices were prepared up to 60 K-file and obturated. Teeth were resected 3 mm from the apex using a cross-cut fissure bur at 90° angle to the long axis of the tooth. Root end cavities of 3 mm were prepared in each of the teeth with an ultrasonic tip to receive the root end filling material. Group 1 - mineral trioxide aggregate (MTA), Group 2 - Biodentine, and Group 3 - Geristore. The samples were mounted in resin blocks for sectioning with a hard-tissue microtome and sectioned apically at 1 mm and 2 mm levels from the apex. They were gold sputtered and viewed under SEM for evaluating the adaptation of the material to the canal walls. Results: The mean value for Group II (Biodentine) was lower than the mean value for Group I (MTA) and Group III (Geristore) at 1 mm and 2 mm. Conclusion: Biodentine showed significantly better marginal adaptation as compared to MTA and Geristore.

Evaluation of Her-2 protein in histologically tumor-free margins of oral squamous cell carcinoma: An immunohistochemical study.

Background: The status of the 5-year survival rate and loco-regional recurrence in oral squamous cell carcinoma (OSCC) has remained unchanged over the decades. Recent advances in oral cancer research have revealed that the presence of molecular alterations in histologically tumor-free margins of OSCC has a prognostic significance and can aid in designing therapeutic strategies. However, the literature on molecular studies on histologically tumor-free margins is scant, especially in the Indian population. Considering the prognostic implications of Her-2 in malignancies of the breast, ovary, and OSCC, we aimed to assess the expression of Her-2 protein in histologically tumor-free margins of OSCC and to establish correlation with clinico-pathological parameters. Methods: 4 µ m thick sections from formalin-fixed paraffin-embedded tissue blocks of 40 histologically tumor-free margins of OSCC affecting the buccal mucosa and/or lower gingiva-buccal sulcus and 40 normal oral mucosa samples were subjected to immunohistochemical analysis for the Her-2 antibody. The obtained data were analyzed statistically. Results: The mean ages in study and control groups were 49.83 years (SD ± 10.43) and 37.28 years (SD ± 8.61), respectively, with male predominance. Local recurrence was seen in 52.5% of patients. Follow-up data revealed that a total of 71.4% of patients succumbed to mortality and all of them had reported local recurrence. Overall, the presence of local recurrence and the status of survival showed a statistically significant association (p = 0.0001). All the samples in the study and control groups were negative for Her-2 immuno-expression. Conclusion: The study indicated the lack of Her-2 immuno-expression in histologically tumor-free margins of OSCC with several speculated explanations. As it is a preliminary study, further studies employing both immunohistochemistry (IHC) and gene amplification in histologically tumor-free margins of OSCC affecting different anatomical sites are warranted. This will aid in identifying the subset of patients that may benefit from targeted therapy.

COVID-19-associated mucormycosis of head-and-neck region: A systematic review.

BACKGROUND AND AIM: With the second wave of COVID-19, there has been a substantial rise in opportunistic infections like mucormycosis. Mucormycosis is a fatal fungal infection and understanding the associated risk factors and their management plays a key role to reduce mortality and morbidity caused due to such infections. This systematic review was conducted to assess the risk factors, clinical characteristics and to understand the pathogenesis of COVID-19-associated mucormycosis (CAM) affecting the head-and-neck region. METHODS: The PubMed database was searched with the keywords; ((Mucormycosis) OR (invasive fungal sinusitis)) AND (COVID-19) and the PRISMA chart was prepared for the selection of the reports based on the inclusion and exclusion criteria. RESULTS: A total of 261 cases of CAM affecting the head-and-neck region were analyzed in this systematic review. Most of the patients presented with rhino-orbital/rhino-orbito-cerebral form of mucormycosis (rhino-orbital mucormycosis/rhino-orbital-cerebral mucormycosis). Pulmonary mucormycosis along with rhino-orbital form, involvement of hard palate, and maxillary sinus was seen in one case each. A total of 224 (85.8%) patients were diabetic, 68 (30.3%) of them had poor glycemic control. Steroids were administered in 210 (80.4%) patients. Except for two, antifungal treatment was given to all patients. Follow-up data revealed 67 (25.6%) deaths and 193 (73.9%) were alive with one patient lost during follow-up. CONCLUSION: The findings of this systematic review suggested that the occurrence of mucormycosis in COVID-19 patients is related to the inherent effects of COVID-19 infection on the immune system, comorbidities especially diabetes, and treatment aspects. Hence, a detailed understanding of these factors may aid in the personalized management of CAM and improve the disease outcome. RELEVANCE FOR PATIENTS: The risk factors in patients affected by CAM should be recognized and closely monitored in post-COVID-19 patients. A multidisciplinary team must be in place to reduce the mortality and morbidity in such patients.

A comparative evaluation of the antibacterial efficacy of Thymus vulgaris, Salvadora persica, Acacia nilotica, Calendula arvensis, and 5% sodium hypochlorite against Enterococcus faecalis: An in-vitro study.

OBJECTIVES: The aim of this study is to evaluate and compare the antibacterial efficacy of Thymus vulgaris, Salvadora persica, Acacia nilotica, Calendula arvensis, and 5% sodium hypochlorite against Enterococcus faecalis. METHODOLOGY: Herbal extracts of T. vulgaris, S. persica, A. nilotica and C. arvensis were prepared. Tryptone soya broth was used to grow E. faecalis and agar plates were prepared. The tested solutions (Group A: 5% NaOCl, Group B: 20% T. vulgaris, Group C: 12.5% S. persica, Group D: 10% A. nilotica, Group E: 10% C. arvensis) were added to the wells made on agar media. Agar diffusion test was performed. Plates were incubated at 37°C for 24 h. Bacterial zones of inhibition were recorded. RESULTS: The data were analyzed statistically by Analysis of Variance (ANOVA) and post hoc comparison by Tukey's t-test. The highest zone of inhibition against E. faecalis was shown by 5% NaOCl, followed by 10% C. arvensis, 20% T. vulgaris and 10% A. nilotica showed similar comparable antibacterial activity. The least zone of inhibition was showed by S. persica. CONCLUSION: 5% NaOCl showed the maximum antibacterial activity, and herbal products demonstrated significant antibacterial activity against E. faecalis and can be employed as an alternative to NaOCl.

Evaluation of remaining dentin thickness following use of three different rotary nickel-titanium retreatment files: A cone-beam computed tomography study.

AIM: The aim of the study is to measure the amount of remaining dentin thickness (RDT) following retreatment using three different rotary nickel-titanium (NiTi) systems. METHODOLOGY: Mesiobuccal roots of 45 extracted maxillary first molars were prepared up to F2 ProTaper File and obturated. After cone-beam computed tomography (CBCT) imaging, to evaluate the obturation, the samples were randomly assigned to three retreatment groups (n = 15). Group I was retreated with ProTaper Universal retreatment kit, Group II and III with MTWO and D-Race retreatment files, respectively. Postoperatively, all samples were subjected to CBCT imaging and evaluated with AutoCAD software (AutoDesk, Inc.) Mill Valley, California, U.S. to calculate the RDT. Data were statistically analyzed using one-way ANOVA and Tukey's post hoc tests, and the level of significance was set at P = 0.05. RESULTS: The amount of RDT was significantly more in D-Race and MTWO groups when compared to ProTaper group. CONCLUSION: D-Race and MTWO instruments were associated with significantly more RDT than ProTaper.

Grape seed extract: An innovation in remineralization.

AIM: The aim of this study was to determine remineralizing potential of grape seed extract (GSE) compared to casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) and calcium glycerophosphate (CaGP) through pH-cycling model and subsequent evaluation using polarized light microscope (PLM). SUBJECTS AND METHODS: Twenty sound human teeth fragments of ten teeth were obtained from the cervical portion of the roots and were stored in demineralizing solution for 96 h at 37°C to induce artificial root carious lesion. The sections then were divided into four treatment groups including: 6.5% GSE, CPP-ACP, 0.5% CaGP, and control group (no treatment). The demineralized samples were then pH cycled through treatment solutions, acidic buffer, and neutral buffer for 8 days at six cycles per day. The samples were subsequently evaluated using PLM. STATISTICAL ANALYSIS USED: Data were analyzed using ANOVA and Scheffe post hoc comparison test (P < 0.001). RESULTS: PLM data revealed a significantly thicker mineral precipitation band on the surface layer of the GSE-treated lesions compared to the other groups (P < 0.001). CONCLUSION: GSE positively affects the demineralization and/or remineralization processes of artificial root caries lesions.

Bilateral Three Rooted Mandibular Premolars and Four Rooted Mandibular First and Second Molar: A Rare Anatomical Variant.

The mandibular premolars and molars exhibit wide variations in the form of roots and root canals. A bilateral symmetry of three rooted mandibular first and second premolar and four rooted mandibular first and second molar in a same patient is a rare entity and one such case is presented in this case report.

A Rare Case of Tamarind Seed Induced Oral Submucous Fibrosis in a 12-Year-Old Indian Boy.

Oral Submucous Fibrosis (OSMF) is a chronic debilitating, potentially malignant disorder of the oral cavity. It is characterized by restricted mouth opening which results due to abnormal accumulation of collagen in the sub-epithelial layers leading to dense fibrous bands in the mouth. The pathogenesis of the disease is believed to be multifactorial. However, literature reports suggest a strong association of OSMF and arecanut chewing habit. The present paper presents a case of OSMF in a 12-year-old boy without arecanut chewing habit, but with a heavy practice of chewing tamarind seeds.

Histological response of human pulps capped with calcium hydroxide and a self-etch adhesive containing an antibacterial component.

AIM: To compare human pulp tissue response following direct pulp capping with calcium hydroxide and a self-etch adhesive containing antibacterial component. MATERIALS AND METHODS: Sixty-six erupted sound premolars scheduled to be extracted for orthodontic reasons were selected from 17 human subjects. Pulp exposures were made. Direct pulp capping was then performed using calcium hydroxide and a self-etch adhesive containing antibacterial component in its primer. The teeth were then restored with composite resin. Two teeth were maintained intact as a control group. After 7 and 30 days, teeth were extracted and processed for light microscopic examination using a histological scoring system. The teeth were divided into four groups (N = 16) according to the pulp capping materials used and their days of extraction. The results were then statistically analyzed by Mann-Whitney U-test. RESULTS: After the 7-day observation period, the inflammatory reaction to the self-etch adhesive containing antibacterial component group was significantly less severe than that in the calcium hydroxide group (P < 0.05). After the 30-day observation period, the inflammatory reaction was slight in both groups, but specimens with dentin bridge formation in the self-etch adhesive group were significantly less common than those in the calcium hydroxide group (P < 0.05).

Comparative evaluation of immunohistochemistry, histopathology and conventional radiography in differentiating periapical lesions.

BACKGROUND AND AIM: Periapical lesions often present differently on the radiograph resulting in a dilemma in the mind of the dentist to arrive at a final diagnosis. Although, histopathologic diagnosis has been used for confirmation of the true nature of periapical lesion, the concept of transformation of periapical granulomas containing epithelium without cystification into cyst remains controversial. The aim of this in vivo study was to evaluate the efficacy of conventional radiography and histopathology in differentiating periapical lesions in adjunct with immunohistochemical analysis. AIM: Periapical lesions often present differently on the radiograph resulting in a dilemma in the mind of the dentist to arrive at a final diagnosis. Although, histopathologic diagnosis has been used for confirmation of the true nature of periapical lesion, the concept of transformation of periapical granulomas containing epithelium without cystification into cyst remains controversial. The aim of this in vivo study was to evaluate the efficacy of conventional radiography and histopathology in differentiating periapical lesions in adjunct with immunohistochemical analysis. MATERIALS AND METHOD: Thirty patients having large periapical radiolucency that do not heal successfully with routine endodontic therapy in relation to either maxillary or mandibular anterior teeth were selected for the study. Intraoral periapical radiographs were obtained and provisional diagnosis of the apical areas were made. Endodontic surgery was performed to enable histopathogical investigation. The histopathological interpretation was done to arrive at a final diagnosis and selected questionable granulomas were subjected for cytokeratin (CK-14) stain. RESULTS: The histopathological profile of lesions consisted of 66.66% periapical granulomas, 10% cysts, 6.67% abscess and 16.67% granulomas with cystic potential. The radiographic and histopathologic correlation was found in only 30% of these cases. Strong CK-14 expression was observed in all five cases of periapical granuloma with cystic potential. CONCLUSION: The radiographic diagnosis of periapical lesions remains inconclusive. Although histopathologic examination of periapical lesions gives true nature, the precise nature of subsets of periapical granulomas may be achieved with adjunct use of immunohistochemical markers.

An insight into the regulatory mechanisms of cells involved in resorption of dental hard tissues.

Dental resorptions constitute a challenge to dentistry due to the complexity of cellular and molecular biology. The various cells involved in resorption, collectively orchestrate the interplay between various cytokines, hormones, enzymes, and hard tissues influencing the progression of resorption. The concern and curiosity on this subject are not new. This paper attempts to review the various regulatory mechanisms of cells involved in resorption of mineralized dental tissues.

Comparative evaluation of the enamel bond strength of 'etch-and-rinse' and 'all-in-one' bonding agents on cut and uncut enamel surfaces.

AIMS AND OBJECTIVES: To compare tensile bond strength of an 'etch-and-rinse' bonding agent (Single bond,3M ESPE, MN, USA) with an 'all-in-one' bonding agent (iBond, Heraeus Kulzer, NY, USA) on cut and uncut enamel surfaces. The null hypothesis tested is that the 'all-in-one' bonding agent matches the 'etch-and-rinse' bonding agent in terms of tensile bond strength to enamel. MATERIALS AND METHODS: Forty extracted human mandibular teeth were used for the study. Twenty teeth with intact enamel surfaces were divided into two groups of 10 teeth each. The enamel surfaces of the 20 teeth were prepared and assigned to two more groups of 10 teeth each. One group each of intact and prepared enamel surfaces were used to bond with the 'etch-and-rinse' bonding agent [Single bond (SB), 3M ESPE, MN, USA] and the other two groups one each of intact and prepared enamel surfaces were used to bond with the 'all-in-one' bonding agent [ iBond (IB), Heraeus Kulzer, NY, USA]. The tensile bond strength was measured on the universal testing machine (Unitek, 9450 PC, FIE, INDIA) at a cross head speed of 1 mm / minute. RESULTS: The results were statistically analyzed using a one-way ANOVA and student 't' test. The values for the 'etch-and-rinse' bonding agent SB were significantly higher for both the cut and uncut surfaces, compared to the 'all-in-one' bonding agent IB (P < 0.05). The all-in-one bonding agent resulted in a higher bond strength on the cut enamel surfaces. CONCLUSIONS: Based on the results, it is advisable to use the 'etch-and-rinse system' in a clinical situation requiring bonding on enamel alone.

Effect of pre-heating composite resin on gap formation at three different temperatures.

AIM: The study aims to evaluate and compare total gap surface area formed after restoration of class II cavities with Filtek Z350 and P60 at room temperature, 37°C and 54°C. MATERIALS AND METHODS: Thirty extracted maxillary and mandibular molars were taken and divided into six groups of five teeth each. Standardized class II cavities were made and were restored with Filtek Z350 and P60, both at room temperature, 37°C and 54°C. Group 1(a) was restored with Filtek Z350 at room temperature, Group 1(b) with Filtek Z350 at 37°C and Group 1(c) with Filtek Z350 at 54°C. Group 2(a) was restored with P60 at room temperature, Group 2(b) with P60 at 37°C and Group 2(c) with P60 at 54°C. After storing the samples in distilled water at room temperature for 48 hours, longitudinal sectioning was done to obtain tooth restoration interface. The interfaces were then examined under compound light microscope with digital output and analyzed using Image J analysis software. RESULTS: The results demonstrated better adaptation and less total gap area formation at 54°C as compared to room temperature and 37°C. CONCLUSIONS: Based on the results of this study, it is suggested that use of P60 is better suited for posterior restorations at 54°C as compared to Filtek Z350 universal nanohybrid at room temperature.

Successful apexification with resolution of the periapical lesion using mineral trioxide aggregate and demineralized freeze-dried bone allograft.

Immature teeth with necrotic pulp and large periapical lesion are difficult to treat via conventional endodontic therapy. The role of materials such as calcium hydroxide and mineral trioxide aggregate in apexification is indispensable. This case report presents the successful healing and apexification with combined use of white mineral trioxide aggregate and demineralized freeze-dried bone allograft.