Evaluation of Microleakage Using Dye-penetration Method in Three Different Composite Resin Core Build-up Materials: An In Vitro Study.

AIM: Aim of the current research is to establish and assess the microleakage in bulk-fill composite, nanohybrid ormocer-based resins, and nanofilled composite resin core build-up materials employing the dye-penetration technique. MATERIALS AND METHODS: Sixty human mandibular first premolar teeth with a solitary root canal without dental caries were chosen for this research. Each specimen was subjected to decoronation of 2 mm from the cementoenamel junction (CEJ), following which the root canal treatment procedure was rendered complete. A space for the post was made for all the 60 samples. Following positioning of the post, specimens were allocated into one of the following three investigational groups (20 specimens in every group) on the basis of the core build-up materials used as group I: bulk-fill composites, group II: nanohybrid ormocer-based resins, and group III: nanofilled resin composites. Direct composite was used for core build-up and subjected to light-curing. Following this, the specimens were immersed in 1% methylene blue solution for 24 hours interval. Each section was evaluated for dye diffusion employing a stereomicroscope with software at a magnifying power of 40× and surface contact between dentin and base of the material was evaluated under scanning electron microscope. RESULTS: Nanohybrid ormocer-based composites exhibited the least microleakage at 1.12 ± 0.14, in pursuit by nanofilled composite resins at 1.79 ± 0.09, and finally the bulk-fill composites at 2.85 ± 0.11, amid the investigational groups studied. A statistically significant difference amid the three dissimilar cores buildup substances was found upon analysis of variance. CONCLUSION: Despite the study limitations, this research came to a conclusion that each of the three investigated core build-up substances exhibited microleakage. However, amid the three, nanohybrid ormocer-based composites depicted the lowest amount of microleakage in pursuit by the nanofilled resins and the bulk-fill composites. CLINICAL SIGNIFICANCE: Core build-up is an important requirement as the remaining tooth substance following root canal treatment reduces and needs reinforcement with core build-up to sustain the tooth structure and provide resistance. A vital mandate for enduring efficiency of the restoration in the mouth is high-quality adhesive bond of these agents to cavity walls with diminished microleakage.

Comparative Evaluation of Intrapulpal Thermal Changes during the Polymerization of Different Adhesive Resin Materials: An In Vitro Study.

AIM: Aim of this study was to assess the thermal changes within the pulp at the time of polymerization of three different adhesive resin materials. MATERIALS AND METHODS: Sixty human premolar teeth that had been recently extracted for orthodontic reasons and were devoid of dental caries/flaws were included in this research. Following preparation of the cavities, all 60 samples consisting of 20 premolars in every group, depending on the adhesive resins that were positioned as were assigned at random to one of the following three groups: Group I: RelyX self-adhesive resin cement; Group II: Breeze self-adhesive resin cement; Group III: Pan F self-etch adhesive resin cement. The temperature changes were calculated using a thermocouple wire attached to a digital thermometer. The dissimilarities amid the baseline temperature as well as the temperatures at different time intervals (1, 5, 10, and 15 minutes) were established. RESULTS: The thermal value was higher at first minute (1.84 ± 0.34) and gradually reduced at 5 minutes (1.36 ± 0.29), 10 minutes (0.62 ± 0.11), and 15 minutes (0.06 ± 0.03) in RelyX self-adhesive resin cement. The maximum thermal value was found at the first minute (2.66 ± 0.21) and gradually reduced at 5 minutes (1.42 ± 0.13), 10 minutes (0.86 ± 0.09), and 15 minutes (0.28 ± 0.01) in Breeze self-adhesive resin cement. The higher thermal value was found at the first minute (1.98 ± 0.19) and gradually reduced at 5 minutes (1.49 ± 0.14), 10 minutes (0.76 ± 0.10), and 15 minutes (0.16 ± 0.09) in Pan F self-etch adhesive resin cement and there was a statistically significant difference found between various time points and with all three adhesive resin material groups (p <0.001). CONCLUSION: This current research arrived at a conclusion that each of the three adhesive resin substances showed a safe temperature change within the pulp. However, the lowest heat scores within the pulp were depicted by RelyX self-adhesive resin in pursuit by Pan F self-etch adhesive resin cement as well as the Breeze self-adhesive resin cement in that order. CLINICAL SIGNIFICANCE: The clinical triumph of a restoration is dependent partially on the method of cementation, which is utilized to establish a connection amid the restoration and the tooth. Temporary and permanent pulp inflammation can be avoided by the decreased temperature changes in the adhesive resin cement at the time of polymerization.

A Scanning Electron Microscope Evaluation of the Efficacy of Different Fluoride-releasing Dental Restorative Materials to Prevent Enamel Demineralization: An In Vitro Study.

AIM: Aim of the present research was to investigate the effectiveness of various fluoride-releasing dental restorative agents in preventing demineralization of enamel. MATERIALS AND METHODS: Eighty human mandibular permanent molar teeth constituted the study group. All samples were subjected to storage in thymol, after which they were taken out to prepare alike proximal box in each. Inductions of artificial enamel surface lesions were done by placing the teeth in demineralizing solution for 96 hours. Subsequently, all 80 molars were randomly assigned to any of the four groups (i.e., 20 in every individual group) according to the restoration as group A: giomer (composite resin containing surface pre-reacted glass-ionomer fillers), group B: compomer (polyacid-modified composite resin), group C: resin-modified glass-ionomer cement (RMGIC), group D: fluoride-releasing composite. After this, the pH cycling was performed, and the samples were subjected to examination beneath scanning electron microscope (SEM). RESULTS: Higher mean areas of remineralization were noted when RMGIC (96.34 ± 0.06) was used followed by the compomer (109.52 ± 0.17), giomer (118.39 ± 0.82), and the fluoride-releasing composite group (129.27 ± 0.31) in that order. A statistically significant difference was seen amid the investigational groups that utilized different restorative agents (p <0.001). A pairwise evaluation that was performed revealed that except for the giomer group and the compomer group, a statistically significant difference (p <0.001) was found among the experimental groups. CONCLUSION: This research infers that the RMGIC-treated samples exhibited significantly superior performance in preventing enamel demineralization in comparison to compomer, giomer as well as fluoride-releasing composites. CLINICAL SIGNIFICANCE: One among the highly frequently employed anticariogenic materials is fluorides. Owing to this characteristic, they are integrated into numerous restorative substances. Nevertheless, the quantity and speed of fluoride release differ in different agents, which translates to the efficacy of the restorative agent in avoiding demineralization about the restoration.

Evaluation of Wettability of Three Saliva Substitutes on Heat-polymerized Acrylic Resin-An In vitro Study.

AIM: The aim of the present study was to evaluate the wettability of three saliva substitutes on heat-polymerized acrylic resin. MATERIALS AND METHODS: Heat-cured acrylic resins 150 were made and divided into three groups containing 50 samples each, i.e., group 1 Aqwet, group 2 Biotene, and group 3 Mouthkote. The prepared wax pattern was cut using 30 × 30-mm two square glass plates along the sides using a sharp carver. The uniformity of the wax samples was checked using the wax gauge. The wax samples were invested using dental plaster in varsity flasks. The samples were prepared using conventional heat-cure denture base acrylic resin. A goniometer was used to calculate receding and advancing contact angles for dynamic contact angle analysis. RESULTS: The least mean value of advancing and receding contact angles was seen in group 1 Aqwet (68.12 ± 1.30 and 58.56 ± 0.10) followed by group 2 Biotene (81.64 ± 0.88 and 74.89 ± 0.45), and group 3 Mouthkote (85.76 ± 1.02 and 80.63 ± 0.66). A significant difference was found between the groups statistically with a p value of 0.001. A significant difference was found on multiple comparisons between group 1 vs group 3 and group 1 vs group 2 with different receding and advancing contact angles of saliva substitutes analyzed with Turkey's post hoc test. CONCLUSION: The lowest advancing and receding contact angle values were significantly seen in the Aqwet saliva substitute followed by Biotene and Mouthkote on heat-polymerized acrylic resin. CLINICAL SIGNIFICANCE: The clinical significance of the saliva substitute's good wetting property on acrylic denture base. The quality of life of the patients with xerostomia can be improved using a suitable saliva substitute.

In Vitro Analysis of Different Polishing Systems on the Color Stability and Surface Roughness of Nanocomposite Resins.

AIM: To assess the different polishing systems on the color stability and surface roughness of nanocomposite resins. MATERIALS AND METHODS: A total of 60 composite resin samples were fabricated. The Tetric N Ceram composite was compacted into the custom-made cylindrical metallic mold of internal diameter 6 × 6 mm. Based on the polishing system used, sixty samples were divided into three groups. Group I: Sof-Lex, group II: Shofu super-snap polishing disks, and group III: Astropol. The samples in each group were immersed in beverage, that is tea. Spectrophotometer was used to measure the color of the samples after staining period. And surface profilometer was used to measure all surface roughness. RESULTS: Of the three groups, Sof-Lex polishing group reported the least mean value of 0.458 ± 0.118 succeeded by Astropol polishing group (0.494 ± 0.121) and Shofu super-snap polishing group (0.540 ± 0.031) having the higher mean value. Statistically significant difference was found between the different polishing systems calculated by analysis of variance. And color change between the groups was not statistically significant. CONCLUSION: We conclude that a composite polished with Sof-Lex was a superior polish compared to Astropol polishing group and Shofu super-snap polishing group. There was only a minimal difference in the color stability of the composite between the groups. CLINICAL SIGNIFICANCE: Excellent finishing and polishing are the critical steps to enhance the esthetics and longevity of the composite restorations. High strength, fracture toughness, surface hardness, optimum polishability, and gloss are the functional properties which need assessment while a resin composite is used for restoration. How to cite this article: Dhananjaya KM, Vadavadagi SV, Almalki SA, et al. In Vitro Analysis of Different Polishing Systems on the Color Stability and Surface Roughness of Nanocomposite Resins. J Contemp Dent Pract 2019;20(11):1335-1338.

Comparison of Different Post Systems for Fracture Resistance: An in vitro Study.

INTRODUCTION: Endodontic restoration becomes a challenging task for the clinician because of severe loss of coronal tooth structure owing to trauma, caries, restorative, and endodontic procedures. The restoration of these teeth requires the use of a post and core as individual units or as abutment supports for fixed or removable restorations in a predictable long-term manner. AIM: To compare and assess the compressive bond strength of glass, quartz, and carbon fiber posts restored with porcelain-fused-to-metal (PFM) crown. MATERIALS AND METHODS: A total of 45 upper central incisor teeth having straight root canals, similar anatomically root segments, and fully developed apices were selected. Teeth were divided into three groups of 15 teeth after endodontic treatment. Group I: Teeth inserted with the prefabricated glass fiber post. Group II: Teeth inserted with the quartz fiber post. Group III: Teeth inserted with carbon fiber post. The posts were placed and core was fabricated using composite restoration followed by PFM crown cementation using adhesive resin. Compressive load required to fracture the tooth was measured using a universal loading machine. The difference between the variables was assessed by one-way analysis of variance, followed by Tukey's post hoc test. RESULTS: The compressive strength exhibited by carbon fiber posts was highest with a mean of 668.33 ± 26.397, followed by quartz fiber post (635.80 ± 30.390). Least compressive strength was exhibited by glass fiber post (567.53 ± 26.632). An analysis of variance shows statistically highly significant difference (p < 0.005) among the posts used. CONCLUSION: This study concluded that the carbon fiber posts had higher compressive strength than other quartz, glass fiber posts. CLINICAL SIGNIFICANCE: Endodontic treatment results in loss of a significant part of the tooth structure. Posts restore these teeth and provide retention.

Effect of Acidic Beverages on Color Stability and Microhardness of Various Esthetic Restorative Materials: A Comparative Study.

AIM: The aim of this study was to assess the effect of acidic beverages on color stability and microhardness of various esthetic restorative materials. MATERIALS AND METHODS: A total of 60 samples were included in the present study. Group I: Microhybrid composite resin, Group II: Nanoceramic, Group III: ORMOCER (Organically Modified Ceramics). 10 mm internal diameter and 5 mm depth of cylindrical aluminum mold of were utilized to prepare the samples. All the esthetic restorative samples were submerged for 10 min in 25 ml of acidic drink (Coca-Cola) each day up to 15 days. Vickers diamond intender was used to measure the microhardness of each sample. These values were calculated with baseline, 7th, and 15th days for final microhardness values. RESULTS: The mean surface microhardness of 63.20 ± 0.46 was shown by Group III which was slightly more than that in Group II (60.08 ± 0.34) and Group I (58.10 ± 1.76). Analysis of covariance did not show any statistically significant difference between the groups. The samples in Group I showed the highest reduction in surface microhardness value after immersion into acidic drink, followed by Group II and Group III on 7th day and 15th day. A statistically significant difference (P < 0.001) was found on the 7th day. CONCLUSION: The present study concludes that the Organically Modified Ceramics esthetic restorative material showed the finest behavior after being dipped in the acidic drink followed next by Nanoceramic and Microhybrid composite resin.

Prevalence of Tooth Shade and its Correlation with Skin Colour - A Cross-sectional Study.

INTRODUCTION: Aesthetics has become an important issue in modern society. Tooth shade is one of the factors in determining aesthetics. Studies have revealed that tooth shade is influenced by age, gender, eye colour, skin colour and other factors. AIM: The present study was aimed to assess the prevalence of tooth shade and its correlation with skin colour. MATERIALS AND METHODS: A total of 300 subjects aged 18-20 years were evaluated for tooth shade using Vitapan - 3D shade guide. Anterior teeth were checked under natural light and facial skin colour by Lakme liquid foundation make up as a shade guide. Data was analysed using chi square test and spearman's correlation. RESULTS: Out of 300 students, 114 (38.00%) had A2 tooth shade; the least prevalent tooth shade among Chitradurga population was C1 (4.00%). There was a positive correlation between tooth shade and skin colour which was found to be statistically significant (p <0.05). CONCLUSION: The most prevalent tooth shade among Chitradurga population was A2 and least was C1. There was a significant correlation between tooth shade and skin colour with lighter skin tone subjects having lighter tooth shade hence skin colour can be used as a guide for shade selection.

Partial Edentulism and its Association with Socio-Demographic Variables among Subjects Attending Dental Teaching Institutions, India.

BACKGROUND: Despite advances in preventive dentistry, edentulism is a major public health issues worldwide. Edentulism is an enervating and unrepairable condition and is described as the "final marker of disease burden for oral health." The objectives of the present study are to determine the relationship between socio-demographic variables and partial edentulism, and to evaluate the prevalence of various classes of partial edentulism by using Kennedy's classification. MATERIALS AND METHODS: Cross-sectional, descriptive study was conducted in an institution, on randomly selected individuals. The study group included adult patients who attended the outpatient Department of Prosthodontics during February-April 2015 formed the study participants. Data were collected by using a pre-formed pro-forma and Chi-square test was used to explore the relationship between two variables. RESULTS: A population comprised of 384 individuals between the age group of 18 and 35 years. Of these, 204 (53.12%) were males and 180 (46.88%) were females. Two hundred and eighty eight individuals were partially edentulous showing a prevalence rate of 75%. 51.04% of the study subjects were lost their teeth because of periodontol disease. 73.4% belonged to the upper middle class and 75.4% were in lower middle class in partially edentulous subjects. 45.8% had a fair oral hygiene status. Kennedy's class III was the most common type of partial edentulism in upper jaw and lower. CONCLUSION: The present study concluded that prevalence of partial edentulism among the study population was high. They need community-based oral health programs to increase the awareness and reduce the risk of tooth loss.

Botulinum toxin for the treatment of hyperfunctional lines of the forehead.

BACKGROUND: In the 21(st) century, we live longer and a more active life. However, while our adult longevity continues to extend, society does not welcome a tired and aged appearance. We wish to continue to look as young as possible. Most facial rejuvenation techniques such as surgery and injection of collagen, silicone, or autogenous fat do not address the fact that these lines are functional, i.e. they do not target the cause of hyperfunctional lines: the underlying facial mimetic musculature. AIM: To find the efficacy of Botulinum toxin for the treatment of hyperfunctional lines of the forehead. MATERIALS AND METHODS: The present study consisted of 25 subjects in the age group of 25-65 years with forehead wrinkles, who visited the Department of Oral and Maxillofacial Surgery, CIDS, Virajpet. The materials used for Botulinum toxin treatment were Botulinum toxin A, a standard freezer, sterile saline solution, alcohol swabs, and insulin syringes with 30 gauge needles. RESULTS: Of the 25 patients, 21 patients showed satisfactory improvement of their hyperfunctional facial lines within 72 h. Maximum improvement was noted in the age group of 25-40 years, while the older age group of 50-65 years showed less improvement. Maximum improvement was seen in type 5 skin, followed by type 4 and type 3 skin. Type 2 skin showed the least improvement. CONCLUSION: We conclude that Botulinum toxin A is a safe and efficacious method of nonsurgically eliminating hyperfunctional facial lines of the forehead in the aesthetic patient for a period of 4-6 months.

Variation in Size and Form between Left and Right Maxillary Central Incisor Teeth.

BACKGROUND: To compare the variation in size of left and right maxillary central incisors for male patients (using digital calipers of 0.01 mm accuracy). To compare the variation in size of left and right maxillary central incisors for female patients (using digital calipers of 0.01 mm accuracy). To find out the difference between the maxillary central incisors of men and women. Its clinical applicability if difference exists. MATERIALS AND METHODS: A total of 70 dental students of PMNM Dental College and Hospital were selected. Of 70 dental students, 40 male and 30 female were selected. Impressions were made for all subjects, using irreversible hydrocolloid (Algitex, manufacturer DPI, Batch-T-8804) using perforated stock metal trays. The mesiodistal crown width and cervical width were measured for each incisor and recorded separately for left and right teeth. The length was measured for each incisor and recorded separately for left and right maxillary central incisor using digitec height caliper. RESULTS: The mean value of maximum crown length of maxillary left central incisor of male was greater in length compared with maxillary right central incisor. Mean value of maximum crown length for male patient right and left side was greater compared with maximum crown length of female patient. CONCLUSION: When compared the dimensions of teeth between two sex, male group shows larger values to female group.