Assessment of Flexural and Compressive Strengths of EQUIA, GC Gold Hybrid, and Conventional GIC Restorative Materials.

Objectives: This in vitro research was performed to assess the flexural and compressive strengths of EQUIA, GC Gold Hybrid (GH), and conventional glass ionomer cement (GIC) restorative materials. Materials and methods: This study compares three restorative. Materials: group I-EQUIA Forte GIC, group II-GC GH, and group III-conventional GIC for compressive and flexural strength evaluation. With a specially made Teflon mold, thirty-six cylindrical test specimens measuring 4 mm × 5 mm in dimension were created. They were then placed in 20 mL of deionized water and kept at 37°C for 3 hours every day for 30 days. Later, they were subjected to compressive strength and flexural strength using the universal testing machine. Statistics were used to examine each and every result. Result and Conclusion: EQUIA had the highest average compressive strength and flexural strength, whereas traditional GIC restorative material had the lowest.

Evaluation of Low-Level Laser Therapy on Orthodontic Tooth Movement: A Randomized Control Study.

BACKGROUND: Fixed orthodontic treatment is time-consuming procedure. Pain is usually associated with orthodontic treatment. The aim of the present study was to evaluate the role of low-level laser therapy (LLLT) on orthodontic tooth movement (OTM) duration and pain perception. MATERIALS AND METHODS: This randomized double-blind splint-mouth controlled clinical study includes 20 (8 males and 12 females) orthodontic patients requiring bilateral canine retraction. Time taken for canine retraction with LLLT (Group A) over control (Group B) quadrant on the same patient was assessed along with pain experience using facial pain scale. The data were tabulated and statistically evaluated using SPSS 20 for windows (Microsoft, Chicago, IL, USA) and t-test with P < 0.05. The difference in pain was evaluated with Wilcoxon signed-rank test. RESULTS: There was no difference in values for age and sex of patient for tooth movement and pain (P > 0.05). There was statistically significant decrease in rate of canine retraction in Group A compared to Group B. There was statistically significant difference for maxillary and mandibular arches in Group A whereas it was not significant in Group B. Pain experience was statistically significant till 2nd day, and after 3rd day, it was not significant between the groups. CONCLUSION: LLLT can reduce the fixed OTM timing and pain experience.

Cytotoxic and Genotoxic effect on the Buccal Mucosa Cells of Patients Undergoing Fixed Orthodontic Treatment.

AIM: To evaluate the presence of metal ions and deoxyribonucleic acid damage on the cells of buccal mucosa in subjects scheduled to undergo fixed orthodontic treatment. MATERIALS AND METHODS: Eighty patients scheduled to undergo orthodontic treatment were included in the present study. Samples were collected from buccal mucosa of the subjects at five different intervals: before the starting of the fixed appliance therapy, 5 months after the insertion of the appliance, 10 months after insertion of the appliance, 15 months after insertion of the appliance and 20 months after insertion of the appliance. Flow cytometry was further used for assessment of apoptosis. Comet assay was used for evaluating the metal ions associated deoxyribonucleic acid ((DNA) damage of buccal epithelial cells. Atomic absorption spectrometry was used for measuring the nickel (Ni), chromium (Cr) and zinc (Zn) levels in the cells of the buccal mucosa. Analysis of data was done by SPSS software version 16.0. RESULTS: A significant increase in the Ni, Cr and Zn concentra -tion during orthodontic treatment was observed. A progressive non-significant decrease in the percentage of viable cells from a baseline value to the end of the treatment was observed. A significant increase in the head diameter, DNA in tail and tail length, starting from the pretreatment value to the end of orthodontic treatment, was also observed. CONCLUSION: Timely checking of deoxyribonucleic acid (DNA) damage and nuclear changes should be done for detecting earlier adverse changes. CLINICAL SIGNIFICANCE: In patients wearing orthodontic appliances, no clinical impact occurs by wearing fixed appliances.

Evaluation of Moyer's mixed dentition space analysis in Indian children.

AIM AND OBJECTIVES: Tooth size prediction values are not universal for all ethnic and racial groups. The present study evaluated the applicability of Moyer's mixed dentition space analysis in the Marwari community of Rajasthan, India. MATERIALS AND METHODS: The mesiodistal dimension of permanent mandibular incisors, maxillary and mandibular canine, and premolars of both sides were measured and averaged in 200 adolescents (100 males and 100 females) of the Marwari population in Rajasthan using digital Vernier caliper. Data were statistically analyzed using Student's t-test. The data were then compared with Moyer's predicted values. The tooth measurements of male and female participants were compared with unpaired t-test. RESULTS: Moyer's prediction chart was not comparable with the study population group. The coefficient of correlation and coefficient of determination in our study was 0.57 and 0.25, respectively. Mesiodistal width of measured teeth was lesser in females compared to males for both canine and premolars (P = 0.471 and P = 0.0001, respectively). CONCLUSION: There was significant statistical difference between values of the present study and Moyer's prediction values. Hence, new regression equation and prediction table can be used to predict mesiodistal dimensions of canine and premolars in Marwari children of Rajasthan.

In vitro evaluation of shear bond strength and microleakage of different pit and fissure sealants.

AIM AND OBJECTIVES: Fissure caries is most common in children due to deep pit and fissures. Pit and fissure areas on the occlusal surface of the teeth make them susceptible to dental caries, which need to be prevented or restored. Fissures sealant reduces the risk of occlusal caries. The present study was done to evaluate microleakage and shear bond strength of various fissure sealants. MATERIALS AND METHODS: Thirty-six extracted molars were randomly allocated equally (n = 12) into three groups with three different sealants to evaluate shear bond strength and microleakage at sealant space. The shear bond strengths was evaluated with one-way analysis of variance and microleakage by Kruskal-Wallis nonparametric test using the Statistical Package for the Social Sciences version 18.0 (Chicago: SPSS Inc, 2009). RESULTS: Tetric flow (16.8 MPa) recorded the highest shear bond strength and the difference was statistically significant with enamel loc (12.8 MPa). There was no statistically significant difference in relation to microleakage (P > 0.05) in the tested groups. CONCLUSIONS: Tetric flow recorded the highest shear bond strength and the difference was statistically significant with enamel loc. However, there was no statistically significant difference among the groups regarding microleakage.