Evaluation of Antimicrobial Properties and Shear Bond Strength of Conventional Orthodontic Adhesive Modified With Calotropis gigantea Nanoparticles: An In Vitro Study.

INTRODUCTION: Bonding of brackets with adhesives during orthodontic fixed appliance therapy is associated with white spot lesions (WSLs). An adhesive developed with an antimicrobial property is advantageous to prevent decalcification of the enamel surface. The current study assesses the antimicrobial and shear bond strength (SBS) characteristics of an experimental conventional orthodontic adhesive incorporated with different concentrations of nanoparticles (NPs) prepared from the leaves of Calotropis gigantea and compares them with non-admixed conventional adhesive. MATERIALS AND METHODS: A total of 40 premolar teeth therapeutically extracted for orthodontic purposes were randomly assigned to four equal groups of n = 10 each. In control Group I, unmodified conventional adhesive was used to bond the brackets. In the three experimental groups, Group II, Group III, and Group IV, the brackets were bonded with modified conventional adhesive admixed with the C. gigantea NPs in concentrations of 1%, 5%, and 10%, respectively. The agar well diffusion test and the disc agar diffusion (DAD) test were utilized for assessing the anti-microbial activity of the composite discs. The SBS of the groups was determined by a universal testing machine. STATISTICAL ANALYSIS: A one-way ANOVA and Tukey's honestly significant difference (HSD) post-hoc test was used to analyze the difference in shear bond strength and microbial inhibition zone diameter between the groups with a probability (p) value of equal to or less than 0.05 as statistical significance. RESULTS: The mean SBS for Group I without nanoparticles is 6.99±0.75 MPa. The SBS value decreased inversely in proportion to the concentration of NPs: Group II (1% NP) 6.29±0.67 MPa; Group III (5% NP) 4.40±0.47 MPa; and Group IV (10% NP) 1.98±0.21 MPa, which is statistically significant (p < 0.001). The incorporation of C. gigantea NPs resulted in a decrease in the actual microbial potency of the conventional adhesive. CONCLUSION: Isolated C. gigantea NPs, when used alone, proved to have antimicrobial efficacy, but orthodontic adhesives admixed with C. gigantea NPs showed no additive effect, and SBS values decreased with increased concentrations of NPs.

Evaluation of Bond Durability, Surface Morphology, and Remineralization at the Adhesive Interface with Dentin Bonding Agents Modified with Silica-doped Nanohydroxyapatite.

Objectives: To compare and evaluate the bond durability, surface morphology, and remineralization of the adhesive layer with newer adhesive systems modified with novel bioactive nanoparticles. Methodology: Bonding agents evaluated in this study include (a) Conventional dentin bonding agent (CN-DBA) (b) Nanohydroxyapatite (nanoHAP) incorporated dentin bonding agent (NH DBA); (c) Silica doped nanohydroxyapatite (Si nanoHAP) incorporated dentin bonding agent (Si NH DBA). A total of 104 human dentin discs (5 mm × 5 mm × 2 mm) were sectioned. Elemental analysis (Ca/P ratio) and surface morphology of the adhesive layer with different dentin adhesives were evaluated under scanning electron microscopy with energy-dispersive X-ray analysis after speculated storage time of 1 day and 6 months. Microshear bond strength of adhesive restorations with different dentin adhesives was evaluated under universal testing machine and fractographic analysis under scanning electron microscope after speculated storage time of 1 day and 6 months. The results were analyzed using analysis of variance and post hoc analysis. Results: Si-NH-DBA showed highest mean microshear bond strength for both 1 day and 6 months, which was significantly higher compared to conventional nanofilled dentin bonding agent (CN-DBA) and NH-DBA. Si-NH-DBA group showed only 10% reduction in bond strength after 6 months, which was less compared to that of other groups. Similarly, Si-NH-DBA showed higher remineralization with stellate-shaped crystals at the adhesive layer after 6 months with hydrolytic resistant hybrid layer, compared to CN-DBA and NH-DBA. Conclusion: Silica-doped nanohydroxyapatite proved its efficiency on bond stability, remineralization, and hydrolytic resistance when incorporated into dentin bonding agents because of its bioactivity and carbonate-containing apatite-forming ability.

A Comparative Study of Pain and Healing in Post-Dental Extraction Sockets Treated with Ozonated Water/Oil and Normal Saline.

Aim: A comparative study of pain and healing in post-dental extraction sockets treated with ozonated water/oil and normal saline. Purpose: The present study was conducted to evaluate the efficacy of ozonated water/oil in reducing pain and enhancing healing and swelling following dental extractions and surgical removal of impacted mandibular third molars. Patients and Methods: Clinical trial was conducted involving 50 individuals requiring two-stage bilateral removal of tooth of which 25 patients were for asymptomatic bilateral extractions and 25 patients for surgical removal of asymptomatic bilaterally similar impacted mandibular third molars. The patients were divided into two groups following a split-mouth design: In group I, sterile ozonated water was irrigated in the sockets after extraction for 2 min on study side and normal saline on the control side following extraction. In group II, transalveolar extractions/surgical extraction of impacted mandibular III molars were carried out under copious irrigation with sterile ozonated water on study side and normal saline irrigation on control side evaluated by independent observer on 2nd, 4th and 7th day for the efficacy of ozonated water/oil in reducing pain and enhancing healing in post-dental extraction sockets. Results: The use of ozonated water/oil increased the healing rate in all extraction cases, except in 4% of cases in which they did not show any effect of healing in extraction sockets on 7th postoperative day. The use of ozonated water/oil did not show any effects on the healing rate in impaction cases in all postoperative days. The use of ozonated water/oil showed decreased incidence of pain in subjects of both extraction and impaction cases.

Comparative Evaluation of Triphala, Aloe vera, and Chlorhexidine Mouthwash on Gingivitis: A Randomized Controlled Clinical Trial.

AIM: The aim of this study was to assess the effectiveness of two herbal mouthwashes in comparison with Chlorhexidine mouthwash on gingivitis. MATERIALS AND METHODS: This is a triple-blind randomized controlled clinical trial, where in 60 patients were randomly allocated into three study groups: Triphala mouthwash (Group A), Aloe vera mouthwash (Group B), and Chlorhexidine mouthwash (Group C). All groups were treated with scaling and asked to rinse with respective mouthwashes twice daily for 1 month. Clinical parameters such as plaque index (PI), gingival index (GI), and bleeding index (BI) were recorded at baseline, 15 days, and 30 days, respectively. RESULTS: Our results suggested that Triphala group effectively demonstrated a higher reduction in GI and BI index scores compared to A. vera group (P ≤ 0.005) and the effect is equivocal to the reduction seen with Chlorhexidine group. However, no statistically significant difference was observed between the mouthwashes in reduction of PI scores (P > 0.005). CONCLUSION: The results of our study evidenced Triphala to be superior in the reduction of plaque, gingival inflammation, and bleeding compared to that of A. vera. However, the results of our study also indicated that Triphala was as effective as chlorhexidine mouthwash in its ability in reducing plaque accumulation, gingival inflammation, and bleeding. Furthermore, Triphala is relatively free of side effects compared to that of chlorhexidine.

Multifunctional calcium phosphate nano-contrast agent for combined nuclear, magnetic and near-infrared in vivo imaging.

Combination of three imaging techniques such as nuclear, magnetic and near-infrared fluorescence can aid in improved diagnosis of disease by synergizing specific advantages of each of these techniques such as deep tissue penetration of radiation signals, anatomical and functional details provided by magnetic contrast and better spatial resolution of optical signals. In the present work, we report the development of a multimodal contrast agent based on calcium phosphate nanoparticles (nCP), doped with both indocyanine green (ICG) and Gadolinium (Gd(3+)), and labeled with 99m-Technetium-methylene diphosphonate ((99m)Tc-MDP) for combined optical, magnetic and nuclear imaging. In order to obtain the desired tri-modal contrast properties, the concentrations of ICG, Gd(3+) and (99m)Tc were optimized at ∼0.15wt%, 3.38at% and ∼0.002ng/mg of nCP, respectively. The leaching-out of ICG was protected by an additional coating of polyethyleneimine (PEI). Toxicological evaluation of the final construct carried out on healthy human mononuclear cells, red-blood cells and platelets, showed excellent hemocompatibility. In vivo multimodal imaging using mice models revealed the ability to provide near-infrared, magnetic and nuclear contrast simultaneously. The nanoparticles also showed the potential for improved MR based angio-imaging of liver. Retention of intravenously administrated nanoparticles in the liver was reduced with PEGylation and the clearance was observed within 48h without causing any major histological changes in vital organs. Thus, we developed a non-toxic tri-modal nano-contrast agent using calcium phosphate nanoparticles and demonstrated its potential for combined nuclear, magnetic and near-infrared imaging in vivo.