Prevalence of dental caries among coronavirus disease 2019-recovered patients and correlation with salivary total antioxidant capacity in Kalaburagi region of Indian subpopulation.

Background: Coronavirus disease 2019 (COVID-19) has vastly affected mankind worldwide, and its long-term effect on oral health needs to be studied. Aims: The aim of the study was to evaluate the prevalence of dental caries and its correlation with salivary total antioxidant capacity (TAC) in Kalaburagi region of the Indian subpopulation. Methods: About 80 subjects (16-55 years) were included in the study based on selection criteria and were divided into two groups (n = 40). Group 1: no history of COVID-19 infection and Group 2: COVID-19-recovered subjects. Each group was subdivided into two subgroups (n = 20) A and B with and without dental caries. Dental caries was assessed using the decay, missing, filled, treatment (DMFT) index by the World Health Organization. About 5 ml of unstimulated saliva samples was collected and centrifuged at 2000 rpm for 10 min, and the supernatants were collected. Salivary TAC was estimated using 2,2'-azino-bis-[3-ethylbenzothiazoline-6-sulfonic] acid assay and observed under spectrophotometer (734 nm). Statistical Analysis: Data were analyzed using the Shapiro-Wilk test for normality distribution followed by one-way analysis of variance and post hoc Tukey test (P < 0.05). Results: COVID-19-recovered subjects showed a higher prevalence of dental caries and lower TAC levels than non-COVID-19 subjects. Conclusion: Higher prevalence of dental caries with lower levels of salivary TAC was found in COVID-19-recovered individuals.

Evaluation of fracture resistance of maxillary premolars of different geometrical cavities restored with different composite resins incorporated with chitosan nanoparticles.

Background: Composites with 0.2% chitosan nanoparticles (CSN) are used recently; however, this combination needs to be studied in different cavity designs. Aims: The aim of the study was to compare the fracture resistance of maxillary premolars with different cavity geometries restored with different types of composite resins incorporated with 0.2% CSN. Methods: About 130 extracted human single-rooted maxillary premolars were embedded in acrylic molds 2 mm below cementoenamel junction, divided into five groups for cavity preparations of standardized dimensions. Group 1: (control) intact teeth (n = 10), Group 2: Class I cavities (n = 40), Group 3: Class II mesio-occlusal (MO) (n = 40), Group 4: Class II mesio-occluso-distal (MOD) (n = 40). Groups 2, 3, and 4 were subdivided into four subgroups for composite restoration; A: Neo spectra ST-Universal (NST); B: Tetric N-Ceram Bulk-fill (TNC); C: NST + CSN; and D: TNC + CSN and tested for fracture resistance using universal testing machine. Statistical Analysis: One-way analysis of variance and post hoc Tukey's tests were used for data analysis (P ≤ 0.05). Results: In all groups, the highest fracture resistance was found in MOD cavities, followed by MO and least in Class I cavities. Subgroup D (TNC with CSN) showed the highest fracture resistance in all groups (P ≤ 0.05). Conclusion: Tetric N-Ceramic bulk fill with 0.25% CSN showed high fracture resistance in cavities with different geometries.

In vitro comparative evaluation of antioxidative effect of selenium alone and in combination with green tea and alpha-tocopherol on the shear bond strength of universal composite resin to enamel after in-office bleaching.

Background: Antioxidant application soon after bleaching process increases the shear bond strength (SBS) of composite resin to enamel. Aims: The aim of the study was to evaluate the antioxidant effects of selenium alone and in combination with alpha-tocopherol (αT) and green tea (GT) on SBS of composite resin to enamel following in-office bleaching with 38% hydrogen peroxide (HP). Methods: Sixty extracted human single -rooted premolar teeth were cleaned and embedded in acrylic resin blocks at the level of cementoenamel junction(CEJ) followed by bleaching with 38% hydrogen peroxide (HP) and arbitrarily divided into seven groups (n=10) for antioxidant application: Group I (negative control): intact teeth, Group II (positive control): only bleaching, Group III: 10% selenium (Se), Group IV: 10% alpha tocopherol (αT), Group V: 10% αT +10% Se, Group VI: 10% Green tea (GT), Group VII: 10%GT+10% Se. In all groups, self-etch adhesive was applied and composite restoration was done, and specimens were stored in distilled water for 24h followed by SBS evaluation. Statistical Analysis: One-way analysis of variance and post hoc Tukey's tests were used (P < 0.05). Results: The highest SBS was found in negative control Group I (intact teeth) and least in positive control Group II (bleached teeth), whereas in experimental groups, Group VII (GT + Se) showed highest followed by Groups V (αT + Se), III (Se), and VI (GT) and least in Group IV (αT). Conclusion: Combination of selenium with green tea and alpha tocopherol enhanced the SBS of composite resin following in-office bleaching.

Evaluation of cytotoxic effects of fungal origin nanosilver particles on oral cancer cell lines: An in vitro study.

Background: Oral cancer is often associated with poor prognosis and it is found that conventional treatment options cause severe side effects, adjacent tissue disfigurement, and loss of function. Recently, silver nanoparticles (AgNPs) paved their path for cancer treatment. Aim: This study aimed to investigate cytotoxic effects of fungal procured AgNPs on oral squamous cell carcinoma (SCC-9) cell line using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Methodology: The silver nanoparticles were biosynthesized using the fungi Fusarium semitectum. Cell lines were cultured in a 1:1 ratio of Dulbecco's Modified Eagle's medium and Ham's F12 medium and subcultured in a T-75 cm2 flask. Cell count was adjusted to 1 × 105 cells/ml; 50,000 cells/well were seeded into a 96 well plate and incubated at 37°C, for 24 h in 5% CO2 humidified conditions. AgNPs (1.75-50 µl/ml) were added to the plates and further incubated at 37°C for another 24 h. Medium containing cells without AgNPs were used as a control group. Later, 20 µl of MTT was added to each well and incubated for 6 h at above-mentioned conditions. About 0.1 mL of Dulbecco's Modified Eagle's Medium solution was added to each well to solubilize formazan. The absorbance was measured using a Tecan reader at 540 nm. The experiment was repeated thrice independently. The percentage (%) inhibition of growth and the AgNP's concentration that prevents the cell growth by 50% (IC50) were determined. Results: Significant dose-dependent inhibition of the growth of SCC-9 cell lines was seen and IC50 was found at 12 µl/ml concentration of AgNPs. Conclusion: Biosynthesized AgNPs of fungal origin exhibit effective anticancer properties against the SCC-9 cell line.

Evaluation of push-out bond strength of different concentrations of chitosan nanoparticles incorporated composite resin and eighth-generation bonding agent for class II restoration: An in vitro study.

Aim: The aim of this study is to evaluate the push-out bonding strength of class II cavities of maxillary molars restored with different concentrations of chitosan nanoparticles (CSN) incorporated in universal composite resin and eighth-generation dentin bonding agent (DBA). Materials and Methods: Seventy extracted human maxillary first molar teeth were cleaned and mounted in acrylic mold up to 2 mm below cementoenamel junction and mesio-occlusal Class II cavities with standard measurements were prepared. CSN 2% and 0.25% powder were added to the DBA and composite resin. The samples then arbitrarily divided into three groups for restoration: Group 1: composite restoration without CSN (control group) (n = 10), Group 2: 2% CSN (n = 30), and Group 3: 0.25% CSN (n = 30). Groups 2 and 3 were further subdivided into three subgroups (n = 10 each) subgroup A. CSN incorporated in composite resin. B. CSN incorporated in DBA and C. CSN incorporated in composite and DBA. After restoration, push-out bond strength was evaluated in each sample using a universal testing machine, and data collected were statistically analyzed by one-way analysis of variance and Post hoc Tukey tests (P ≤ 0.05). Results: Subgroup 3A (0.25% CSN + composite) has shown an increase in bond strength among all experimental groups with no significant difference between group 1 (control group). Conclusion: CSN 0.25% incorporated in composite or DBA exhibits no harmful effect on the bond strength of class II restorations. Hence, it can be used to improve the antibacterial action and longevity of composite resin.

Unusual Variant of Unicystic Ameloblastoma with CEOT-Like Areas: A Rare Case Report with Review of Literature.

Ameloblastoma is an epithelial odontogenic neoplasm with clinical and histological diversity. They are locally invasive tumors with 3 clinical variants such as solid, unicystic, and peripheral ameloblastomas, and the unicystic variant constitutes only 13%. Histologically, it shows diverse microscopic patterns that may occur isolated or in combination with other patterns. The granular cell variant accounts for 3.5% of all ameloblastoma cases. The eosinophilic granules seen in the cytoplasm of the tumor are thought to be lysosomes and presumably contribute to the pathogenesis of the tumor. Although such a phenomenon is rare in unicystic ameloblastoma, granular cell differentiation in solid multicystic ameloblastoma is a well-established phenomenon. In this paper, we present a unique case of unicystic ameloblastoma with granular cell differentiation with a brief review.

Cytotoxicity evaluation of fungal-derived silver nanoparticles on human gingival fibroblast cell line: An in vitro study.

BACKGROUND: Biosynthesized silver nanoparticles (AgNPs) have been proposed as effective antimicrobial agents against endo-perio pathogens. Determination of cytotoxicity is important for effective clinical use. AIM: The aim is to determine the cytotoxicity of fungal-derived AgNPs on human gingival fibroblast (HGF) cell line using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. MATERIALS AND METHODS: HGF cell cultures were trypsinized and adjusted to 5 × 103 cells/ml and 100-µl cell suspension (50,000 cells/well) and were added to 96-well plate. After 24 h, 100 µl of AgNPs (8-512-µg/ml concentrations) was added and incubated at 37°C for 24 h in 5% CO2 atmosphere. Controls were used without AgNPs. MTT (1 mg/ml) was added and incubated for 4 h at 37°C in 5% CO2 atmosphere. Microscopic examination was done, and absorbance was measured using a microplate reader at a wavelength of 540 nm. Percentage growth inhibition was calculated, and the concentration of AgNPs needed to inhibit cell growth by 50% (CTC50) was generated. RESULTS: CTC50 was found at a concentration of 260 µg/ml. AgNPs exerted less cytotoxicity against HGF cell line and increased with increase in the concentration of AgNPs. CONCLUSION: Fungal-derived AgNPs are safe to healthy cells at a concentration <260 µg/ml. Therefore, they can be effectively used for the treatment of endo-perio lesions.

Antibiofilm efficacy of biosynthesized silver nanoparticles against endodontic-periodontal pathogens: An in vitro study.

BACKGROUND: Endodontic-periodontal pathogens exist as biofilms which are difficult to eliminate. Biosynthesized silver nanoparticles (AgNPs) emerged as newer antimicrobial agents with potential benefits. AIM: The aim of this study is to determine the minimum inhibitory concentration (MIC); evaluate the antibiofilm efficacy of fungal-derived AgNPs against Porphyromonas gingivalis, Bacillus pumilus, and Enterococcus faecalis. MATERIALS AND METHODS: MIC of AgNPs against test pathogens was determined using micro broth dilution method. Serial dilutions of AgNPs ranging from 80 to 1 µg/ml concentration were added to wells containing 10 µl of bacterial inoculum in culture media and control group without AgNPs. For biofilm models, 120 dentin blocks were prepared, sterilized, and contaminated for 2 weeks with (n = 40 each). Group 1: B. pumilus, Group 2: E. faecalis, and Group 3: P. gingivalis and each group is divided into four subgroups (n = 10 each) and treated with distilled water, AgNPs, 2% and 0.2% chlorhexidine (CHX). Colonies counted after 24 h of incubation and statistically analyzed using one-way ANOVA and post hoc Tukey tests. RESULTS: MIC for B. pumilus was determined as 20 µg/ml and 30 µg/ml for E. faecalis and P. gingivalis. AgNPs were effective as 2% CHX against all biofilms compared to control group. Post hoc Tukey test (P < 0.0001) shows no significant difference between groups. CONCLUSION: Fungal-derived AgNPs are effective against endo-perio pathogens.

Evaluation of Enterococcus faecalis adhesion, penetration, and method to prevent the penetration of Enterococcus faecalis into root cementum: Confocal laser scanning microscope and scanning electron microscope analysis.

AIM: To ascertain the role of Enterococcus faecalis in persistent infection and a possible method to prevent the penetration of E. faecalis into root cementum. METHODOLOGY: One hundred and twenty human single-rooted extracted teeth divided into five groups. Group I (control): intact teeth, Group II: no apical treatment done, Group III divided into two subgroups. In Groups IIIa and IIIb, root apex treated with lactic acid of acidic and neutral pH, respectively. Group IV: apical root cementum exposed to lactic acid and roughened to mimic the apical resorption. Group V: apical treatment done same as Group IV and root-end filling done using mineral trioxide aggregate (MTA). Apical one-third of all samples immersed in E. faecalis broth for 8 weeks followed by bone morphogenetic protein and obturation and again immersed into broth for 8 weeks. Teeth split into two halves and observed under confocal laser scanning microscope and scanning electron microscope, organism identified by culture and polymerase chain reaction techniques. RESULTS: Adhesion and penetration was observed in Group IIIa and Group IV. Only adhesion in Group II and IIIB and no adhesion and penetration in Group I and V. CONCLUSION: Adhesion and penetration of E. faecalis into root cementum providing a long-term nidus for subsequent infection are the possible reason for persistent infection and root-end filling with MTA prevents the adhesion and penetration.