Dental Research

Load-deflection characteristics of coated and noncoated nickel-titanium wires in self-ligating brackets using a modified bending test: An in vitro study Tripti Tikku, Rohit Khanna, Akhil Agarwal, Kamna Srivastava, Shashank Shekhar, Ivy Shukla Dental Research Journal 2019 16(1):1-6 Background: To determine and compare the force-deflection values of different types of nickel-titanium (NiTi) wires during unloading phase at varying deflections, that is 1 mm, 1.5 mm, 2 mm, and 2.5 mm, with the use of self-ligating ceramic brackets using modified bending test on a typodont under controlled temperature conditions. Materials and Methods: In this in vitro study total of 45 wires of ovoid shape of three different NiTi wires – pseudoelastic NiTi (Group I), heat activated NiTi (Group II), and esthetic coated NiTi (Group III) for maxillary arch were tested after insertion in ceramic self-ligating brackets bonded to plastic teeth of phantom jaw . The maxillary left lateral incisor was removed to simulate a malpositioned tooth which acted as the load site, and load-deflection characteristics were measured during unloading using Instron, and data analyzed statically by two-way analysis of variance ,Tukey's post hoc test, intraclass correlation coefficient and Pearson correlation coefficient. A two-sided (α = 2) P < 0.05 was considered statistically significant. Results: When wires were compared at each deflection statistically significant difference was observed between the three groups of wires (Group I > Group II > Group III) at all the four levels of deflection except for Group II versus Group III at 1 mm, 1.5 mm, and 2 mm of deflection. Statistically significant difference was noted in mean load values for comparisons made at different deflections for each wire except for the comparison made at 1.5 versus 2 mm for Group II and Group III. Conclusion: Overall comparison showed esthetic coated Ni-Ti wires gave significantly lower mean load values, followed by heat activated and pseudoelastic NiTi wires. Thus, heat activated NiTi wires are best suited in patients with severe malpositions/periodontitis, while for esthetically conscious patients esthetic coated NiTi can be used.

Effects of menthol-flavored substances at the cellular level on oral mucosal sites Nanda Prasad, Sarvesh Vijay, A Yashwanth Reddy, S Nonitha Dental Research Journal 2019 16(1):7-11 Background: The purpose of this study was to determine the effects of menthol-flavored substances at the cellular level in different mucosal sites of the oral cavity and to compare the cellular changes between individuals without the habit of chewing menthol-flavored substances and individuals with the habit. Materials and Methods: This was an experimental cytology study including a total of 500 individuals belonging to the age group of 18–45 years based on the inclusion or exclusion criteria. The selected participants were divided into two groups of 250 participants each, based on participants not having the habit of chewing menthol-flavored substances (Group I) and participants having the habit of chewing menthol-flavored substances (Group II). Cytological smears were taken by gently scraping the mucosal surfaces in different sites of the oral mucosa using a wooden spatula and stained with Papanicolaou, analyzed under microscope for any cellular changes. The results were tabulated and statistically analyzed using Chi-square test and Fisher's exact test. P < 0.05 was considered statistically significant. Results: Micronuclei seen in all the participants belonging to group with the habit of chewing menthol-flavored substances with a P < 0.001 which was considered highly significant. Alteration in the nuclear-cytoplasmic ratio was also seen P = 0.001, which showed significant at 1% significance level. Conclusion: Participants with habit of chewing menthol-flavored substances showed the presence of micronuclei and slight alteration in the nuclear-cytoplasmic ratio, which could be directly related to genotoxicity and cell damage.

Impact of occupational dental erosion on oral health-related quality of life among battery factory workers in Bengaluru, India Amit Kumar, Manjunath P Puranik, KR Sowmya, Soni Rajput Dental Research Journal 2019 16(1):12-17 Background: A greater understanding of impact of occupational dental erosion on oral health-related quality of life (OHRQoL) will sensitize both employee and employers to adopt strict protective measures for oral health. The research aimed to determine the relationship between occupational dental erosion and OHRQoL among battery and other factory workers in Bengaluru, India. Materials and Methods: This cross-sectional comparative study enrolled a total of 400 workers. Structured proforma assessed information on sociodemographic details, oral hygiene practices, adverse oral habits, and work-related practices. OHRQoL was determined using oral health impact profile-14 (OHIP-14). Dental erosion was measured using Smith and Knight's tooth wear index modified by Millward et al. 1994 scoring system independent t-test, Mann–Whitney U-test and Spearman's correlation was performed. P < 0.05 was considered statistically significant. Results: The mean age of the participants in the study and control groups was 43.11 ± 8.02 and 45.93 ± 6.16 years, respectively. Less than half of the participants in the study group had positive behavioral work practice. The prevalence and severity of dental erosion was significantly higher in study group (39.5%) than control group (11.5%). Mean OHIP-14 score was significantly lower in study group (23.88 ± 0.88) than control group (26.06 ± 9.67). Dental erosion significantly correlated with work experience and OHIP-14. Conclusion: The findings highlight the impact of occupational dental erosion on OHRQoL. Measures to enhance occupational safety thereby reducing exposure to occupational hazards are needed.

Comparative investigation of primary stability of four different dental implants in low-density bone model Saied Nokar, Amirali Reza Rasouli-Ghahroudi, Elham Shidvash, Faezeh Atri Dental Research Journal 2019 16(1):18-23 Background: Primary stability is one of the prerequisites of immediate loading. The aim of this study was to compare the primary stability of four different implant systems in low-density bone models. Materials and Methods: In this in vitro experimental study, 20 fixtures from four implant body designs were selected: Zimmer Tapered Screw-Vent (ZTSV), NobleReplace Tapered (NRT), Replace Select Tapered (RST), and Dentium SuperLine (DSL). Fixtures were inserted in low-density bone models according to manufacturer drilling protocol by one surgeon. Measurement of insertion torque value (ITV), resonance frequency analysis (implant stability quotient [ISQ]), and reverse torque value (RTV) was recorded for each fixture. The data were analyzed with one-way ANOVA and post hoc tests (Tukey honestly significant difference) (P < 0.05). Results: ZTSV had significantly lower amount of insertion torque in comparison to other systems (P = 0.045). RTV was significantly lower in ZTSV in comparison to DSL and NRT (P = 0.004). ISQ value in NRT (ISQ = 67) was significantly higher than other systems (P = 0.000). The lowest amount of ISQ was in RST system (ISQ = 53) with significant difference (P = 0.000). Conclusion: This study demonstrated that primary stability of different implant systems was not comparable and implant design was effective on ITV, RTV, and ISQ.

Assessment of antimicrobial activity of different concentrations of Tinospora cordifolia against Streptococcus mutans: An in vitro study Sankalp Agarwal, Priyadarshini H Ramamurthy, Bennete Fernandes, Avita Rath, Preena Sidhu Dental Research Journal 2019 16(1):24-28 Background: The antimicrobial property of Tinospora cordifolia has been tested against a variety of microorganisms in the literature. The present study aimed to assess the antimicrobial activity of different concentrations of commercially available T. cordifolia powder against Streptococcus mutans. Materials and Methods: An in vitro study was undertaken in which extract of T. cordifolia was obtained using 100% ethanol by maceration. Seven different concentrations were prepared and tested against S. mutans in brain–heart infusion agar medium. Plates were incubated aerobically at 37°C for 48 h, and zone of inhibition was measured using Vernier caliper. 0.2% chlorhexidine and dimethylformamide were used as positive and negative controls respectively. The data were analysed by descriptive analytic tests. Results: The maximum antibacterial activity of T. cordifolia was observed with a volume of 40 μl at 2% concentration with a zone of inhibition of 19 mm. A 30 μl volume of 0.2% chlorhexidine showed a zone of inhibition of 28 mm, and no zone of inhibition was observed with dimethylformamide. Conclusion: Tinospora exhibited antimicrobial activity against S. mutans. However, it needs to be confirmed further with in vivo studies.

Association between quality of sleep and chronic periodontitis: A case–control study in Malaysian population Vijendra Pal Singh, Joe Yin Gan, Wei Ling Liew, Htoo Htoo Kyaw Soe, Sowmya Nettem, Sunil Kumar Nettemu Dental Research Journal 2019 16(1):29-35 Background: Periodontitis is a public health concern since it is a major factor in tooth loss worldwide and has association with many systemic diseases. Sleep is a complex and essentially biological process and a critical factor for maintaining mental and physical health. Since inflammation is characteristic of both chronic periodontitis and sleep deprivation, few studies in recent years present the contradictory results regarding this potential association. The objective of the present study was to investigate the association between quality of sleep and chronic periodontitis. Materials and Methods: A total of 200 individuals participated in this study. All participants underwent a comprehensive clinical periodontal examination. Case–control were identified using the Centers for Disease Control and Prevention/American Academy of Periodontology case definitions for periodontal disease. The quality of sleep was assessed by Pittsburgh Sleep Quality Index. The univariate and multivariate logistic regression analysis was used to test the influence of variables (quality of sleep, age, sex, ethnicity, education, and socioeconomic status), in the occurrence of periodontitis. Odds ratio (OR) and respective confidence intervals (CIs) were calculated and reported. P ≤0.05 was considered statistically significant. Results: The prevalence of poor quality of sleep was 56.75% in cases (periodontitis group) and 43.24% in control group. There was positive association between quality of sleep and chronic periodontitis (OR = 3.04; 95% CI = 1.42–6.5; P = 0.004). In multivariate logistic regression analysis, only the age was significantly related to the periodontitis (OR = 1.11; 95% CI = 1.07–1.41; P < 0.001), other variables failed to reach the significant level. Conclusion: Poor quality of sleep was significantly associated with chronic periodontitis. Only the age was significantly related to periodontitis among the other covariable measured.

Sealants revisited: An efficacy battle between the two major types of sealants – A randomized controlled clinical trial B Prathibha, P Parthasarthi Reddy, Md Shakeel Anjum, M Monica, BH Praveen Dental Research Journal 2019 16(1):36-41 Background: The aim of this study is comparing the retention and caries preventive effect of the glass-ionomer fissure sealant and resin-based fissure sealant. Materials and Methods: A randomized-controlled split-mouth study was conducted to compare the retention and the caries preventive effect of light-cured resin-based sealant (3M ESPE) and glass ionomer sealant (Fuji VII). The sealants were applied to either the right or the left lower mandibular molars (7-9 yrs of age) in 120 school children, based on the randomization process. They were recalled for assessment of clinical retention at intervals of 3, 6, and 12 months. The caries-preventive effect between the two materials was tested statistically by the McNemar's test for matched pairs, and the differences observed with regard to the retention of the materials was tested by Chi-square tests. The level of significance was set to be at P < 0.05. Results: At the end of 12th month, sealant retention is found to be higher in the resin-based sealant group compared to the glass ionomer group. In the glass ionomer sealants placed, 101 (91%) were caries-free and 10 (9%) had caries. In the resin-based sealant, 105 (94.60%) had sound teeth and 6 (5.4%) had dental caries (P = 0.34). Conclusion: The glass ionomer sealant was less retentive when compared to resin sealants. The caries incidence between the glass ionomer and resin-based sealants was not statistically significant.

A comparative study of the clinical efficiency of chemomechanical caries removal using Carie-Care gel for permanent teeth of children of age group of 12–15 years with that of conventional drilling method: A randomized controlled trial Priyanka Sontakke, Prateek Jain, Aniket Dhote Patil, Gautam Biswas, Pramod Yadav, Diljot Kaur Makkar, Vikas Jeph, Banu Pyari Sakina Dental Research Journal 2019 16(1):42-46 Background: Dental caries is considered as one of the most serious dental diseases that results in localized dissolution and destruction of the calcified tooth tissues. As possible alternatives to conventional techniques of caries removal, chemomechanical caries removal systems have emerged. This study aims to clinically observe the advantages of chemomechanical method of caries removal over conventional technique. Materials and Methods: Inthis randomized controlled trial a total of 60 children with Class 1 open carious lesions were selected for the study. They were divided into two equal groups according to a method of caries removal (30 chemomechanical and 30 conventional on permanent molars). In Group A, caries was removed using the Carie-Care system and in Group B with the conventional drill and were restored equally with glass ionomer cement. The visual analogy face scale was used to determine the level of anxiety in children at baseline, during treatment and after treatment. Results: The results were subjected to statistical analysis using Student's unpaired t-test. It showed that though chemomechanical technique took a marginal increase in time compared to the conventional technique, it was found to be more comfortable for all the children. Conclusion: Chemomechanical technique though time-consuming is definitely superior compared to the conventional technique provided we use a less technique sensitive restorative material which retains in the oral cavity for longer period. It is definitely a better treatment protocol in school-based dental treatment and atraumatic restorative dentistry compared to the conventional technique.

The effect of office bleaching on the color and bond strength of resin restorations Homayoon Alaghehmand, Marzieh Rohaninasab, Ali Bijani Dental Research Journal 2019 16(1):47-52 Background: Bleaching may affect the bond strength of existing composite fillings and may weaken it. Hence, the aim of this study was to find the best method of in-office bleaching with the least effect on microshear bond strength (MSBS) of existing composite resin fillings to tooth structure. Materials and Methods: In this in vitro study, Class V cavities were prepared on buccal surface of 50 extracted third human sound molars. The cavities in 25 teeth had enamel axial walls, Group E, which were divided into five subgroups of E1 through E5 and in 25 teeth had dentin axial walls, Group D, which were divided into five subgroups of D1 through D5. Cavities were treated with Single Bond 2 adhesive system and restored with composite resin (Z250). The corresponding subgroups received similar bleaching methods and materials; 1 – not bleached, 2 – hydrogen peroxide (HP) 25%, 3 – HP + ultraviolet light, 4 – HP + light-emitting diode-curing device, and 5 – HP + diode laser. Teeth colors were monitored before and after bleaching, and MSBS test and failure modes were examined. Results were analyzed with one-way ANOVA and Kruskal–Wallis tests. P < 0.05 was considered significant. Results: One-way ANOVA did not show differences in MSBS of enamel subgroups but showed significant differences in dentin subgroups (P < 0.00). Adhesive fracture in all of the subgroups was the most frequent mode of failure. Kruskal–Wallis test showed that laser was the most effective instrument to change ΔE. Conclusion: Diode laser was the best method for tooth bleaching because lowering the shear bond strength between composite resin and enamel was minimum and also had the most ΔE in tooth bleaching.

In vitro evaluation of coronal discoloration following the application of calcium-enriched mixture cement, Biodentine, and mineral trioxide aggregate in endodontically treated teeth Solmaz Araghi, Atefeh Khavid, Mostafa Godiny, Mahshid Saeidipour Dental Research Journal 2019 16(1):53-59 Background: This study sought to assess and compare coronal discoloration following the application of white mineral trioxide aggregate, Biodentine, and calcium-enriched mixture cement in endodontically treated teeth. Materials and Methods: In this in vitro experimental study, 64 freshly extracted sound human premolars were selected, cleaned, and stored in saline. After cleaning, shaping, and obturation the root canal of the teeth, the teeth were randomly assigned to one control (n = 4) and three experimental (n = 20) groups. In the experimental groups, the cement were applied over the canal orifices in 3-mm thickness. All teeth were then restored with composite resin. Color parameters, according to the CIE L*a*b* system, were measured using Vita Easyshade spectrophotometer before application of cement and at 1 week, 1 month, 2 months, and 3 months after the application of cement. The recorded values were statistically analyzed using descriptive and analytical statistics. For analytical statistics, Kolmogorov–Smirnov test was applied to assess normal distribution of data. ANOVA was used to compare the results at baseline and repeated measures. P < 0.05 was considered statistically significant Results: Significant differences were noted in color change (ΔE) between all time points except between ΔE4 (2 months) and ΔE5 (3 months) (P < 0.01). However, tooth discoloration caused by the three cement was not significantly different (P = 0.343). Conclusion: The three tested cement were not significantly different in terms of causing coronal discoloration in endodontically treated teeth.