Single Nucleotide Polymorphisms of BMP2 Gene Association with Skeletal Class I Crowding: A PCR Study.

AIM AND OBJECTIVE: This study is conducted to find the association of BMP2 (bone morphogenic protein 2) gene variant rs1005464 and rs15705 with skeletal class I crowding cases. MATERIALS AND METHODS: Blood samples from 60 subjects who visited the Department of Orthodontics and Dentofacial Orthopaedics, D.A.P.M.R.V. Dental College, Bengaluru, were taken after written informed consent. These were divided into two groups: group A with 30 subjects having skeletal class I bases with crowding and group B with 30 subjects having skeletal class I bases without visible crowding or spacing (±2 mm). Around 2 mL of venous blood sample was procured from cases and controls after careful examination. All the samples were then subjected to polymerase chain reaction followed by DNA sequencing and capillary electrophoresis. BMP2 rs1005464 and rs15705 gene variants were assessed and Z-Test was used for statistical analysis. RESULT: GG (p = 0.001) and CC (p = 0.0024) genotype of BMP2 gene variant rs1005464 and rs15705, respectively, are significantly associated with skeletal class I crowding cases. CONCLUSION: This study concludes that BMP2 variants rs1005464 and rs15705 can be used as genetic markers for skeletal class I bases having crowding. CLINICAL SIGNIFICANCE: Predisposing genetic markers BMP2 can be identified prior and this would help in predicting the probability of potential crowding in the future and this would help in early prevention and intervention of crowding.

An In Vivo Randomized Clinical Evaluation of the Surface Morphology of Nickel-Titanium, Beta-titanium, and Copper-Nickel-Titanium.

AIM: Variation in the surface roughness of archwires not only leads to more accumulation of plaque but also modifies the coefficient of friction. This necessitated for the present study to evaluate the surface characteristics of 0.016 × 0.022-inch nickel-titanium, beta-titanium, and copper-nickel-titanium archwires, before and after their use in the oral cavity using atomic force microscopy. MATERIALS AND METHODS: The control and experimental samples were measured at three different positions under atomic force microscopy. The surface roughness was measured using roughness average, root mean square, and maximum height before and after use in the oral cavity among 60 adult participants. Data were analyzed using a one-way analysis of variance and Student's t tests using the Statistical Package for Social Software (SPSS) v.20.0. RESULTS: The surface roughness of archwires increased considerably after their clinical use compared to controls for nickel-titanium (p = 0.013) and beta-titanium (p = 0.002). A similar trend was noticed for root mean square where nickel-titanium (p = 0.014) and beta-titanium (p = 0.013) had increased root mean square. Maximum height was also noticed in nickel-titanium (p = 0.031) and beta-titanium (p = 0.016). CONCLUSION: Surface roughness and the level of friction of the orthodontic wires increase significantly for nickel-titanium and beta-titanium after the clinical use. There is a difference in increase of surface roughness of the archwire within and between the bracket slots. CLINICAL SIGNIFICANCE: Nickel-titanium and beta-titanium wires show more roughness and resultant higher friction levels after use in the oral cavity. Hence, care related to plaque accumulation is essential.

Staining the Ground Section of the Tooth Using an Innovative Plant Stain Found in the Pravara Region, India.

AIMS: To assess the staining efficacy of the innovative "Pravara" stain on ground sections of human teeth under a stereomicroscope. In this study, the ground sections were stained with the innovative stain. The stain is obtained from a leafless tree called Terminalia chebula. Terminalia chebula, commonly known as Harad, is found in South Asia from India. Few species are found in the Pravara region of Maharashtra, India. MATERIALS AND METHODS: A total of 40 extracted teeth were collected and ground sections of each tooth were prepared. The samples were randomly divided into two groups: group I-control (without stain), group II-study group (the samples in this group were stained with the help of innovative "Pravara" stain). The sections were graded from I to III according to the differentiation and contrast of tissues. RESULTS: The ground sections in group II stained with Pravara stain demonstrated better contrast for structures within sections under a microscope in comparison with group I (control group). CONCLUSION: The study demonstrates the efficacy of a new innovative Pravara stain, which is a simple, economical, quick, and effective staining method for the ground sections of the teeth. CLINICAL SIGNIFICANCE: This innovative Pravara stain is cost-effective, saves time, ecofriendly, and highlights the anatomical structures more effectively and does not fade easily with time.

A study on the wear of enamel caused by monolithic zirconia and the subsequent phase transformation compared to two other ceramic systems.

PURPOSE: The purpose of this in vitro research project was to evaluate and compare the wear behavior of human tooth enamel opposing monolithic zirconia and other different ceramic restorative materials and also to observe the tetragonal to monoclinic phase transformation in zirconia-based ceramics that may occur while simulating wear occurring at room temperature in a wet environment. MATERIALS AND METHODS: A total of sixty samples were prepared for this study. Fifteen discs of glazed zirconia, 15 discs of polished zirconia without glaze, 15 discs of metal ceramic, and 15 discs of lithium disilicate were fabricated. Sixty extracted premolars were collected and randomly divided into four groups of 15 each. The discs and extracted human premolars were placed onto holders on a two-body wear machine under a constant load of 5 kg to simulate the oral wear cycle. A diffractometer was used to analyze phase transformation. One-way analysis of variance and Tukey's post hoc tests was used. RESULTS: The mean loss of height of tooth samples and its standard deviation for Group I (monolithic zirconia with glaze), Group II (mechanically polished monolithic zirconia without glaze), Group III (porcelain fused to metal), and Group IV (glazed monolithic lithium disilicate) was obtained as 0.2716 ± 0.1409, 0.1240 ± 0.0625, 0.1567 ± 0.0996, and 0.2377 ± 0.1350, respectively. The highest mean loss in height was observed in Group I and the least was observed in Group II. CONCLUSION: Mechanically polished zirconia showed the least amount of enamel wear followed by porcelain fused to metal and glazed monolithic lithium disilicate, whereas glazed monolithic zirconia showed the highest enamel wear.

Addition Silicone Impressions in Fixed Prosthodontics: Clinical Standpoints.

Addition silicones have revolutionized the field of fixed prosthodontics because of their dimensional stability, sufficient tear strength and excellent detail reproduction. This review study aims to provide a detailed description of the essential variables to be taken into account during the process of making addition silicone impressions in fixed prosthodontics. These variables include the selection of appropriate tray type, size, and fabrication; the use of tray adhesive; gingival displacement techniques; manipulation of the impression material; the choice of the impression material's viscosity; impression techniques; and the proper insertion, removal, disinfection, and pouring of the cast. Additionally, this review aims to help doctors produce high-quality impressions by empowering them to critically assess the impressions to spot mistakes and motivating them to redo impressions that have serious problems before submitting them to the laboratory.

A comparative evaluation of colour stability of different resin cements and its influence on the final shade of All-Ceramic Restorations: An in-vitro Study.

Introduction: Colour changes of the luting material can become clinically visible affecting the aesthetic appearance of thin ceramic veneers. Therefore, unfortunately, the long-term success of veneers is tied to the colour stability of the luting agent used to cement them. Aim: To compare the colour stability of different resin cements and its influence on the final shade of overlying ceramic using two different thicknesses of ceramic. Material and Methodology: Sixty disc-shaped specimens of high translucency (HT) A2 shade of two thicknesses (0.5 mm & 1 mm) were prepared from lithium disilicate glass-ceramic. The discs of each thickness were further divided into three groups randomly depending upon the resin cements used. Group A - light cure resin cement - Variolink N LC by Ivoclar Vivadent in clear shade, Group B - base paste of dual-cure resin cement - Variolink N by Ivoclar Vivadent in transparent shade and Group C dual-cure resin cement - Clearfil esthetic cement EX by Kuraray in clear shade were used to compare their colour stability. A spectrophotometer was used for the colour measurements of the specimens before and after accelerated ageing. The colour stability was determined by colour differences (ΔE) using the coordinates L*, a* and b* in the pre and post accelerated ageing. Results: On comparing the three resin cements, Group A showed the lowest ΔE, whereas the highest ΔE was observed in Group B. This finding was constant for discs of both thicknesses. Conclusion: Even though statistically significant results were observed between the groups, they were not visibly differentiable.

Evaluation of Remineralization Seen in Dentin Related to Ceramic Restorations.

BACKGROUND: Recently, the caries management had shifted from extension for prevention to early detection and remineralization of remaining tooth structure using noninvasive techniques. AIM: The present trial was carried out to assess the effect of adding mono-n-Dodecyl phosphate as a surfactant to ceramic on remineralization of dentin. MATERIALS AND METHODS: The 32 teeth were divided into the following four groups randomly (n = 8 each group) - Group I: cavities not restored, Group II: Restored with ceramic, Group III: restored with ceramic and 2% mono-n-Dodecyl phosphate, and Group IV: restored with ceramic and 5% mono-n-Dodecyl phosphate. Knoop indenter microhardness tests were done at 10, 20, and 40 days. The surface was evaluated under scanning electron microscope. The collected data were subjected to statistical evaluation, and the results were formulated. RESULTS: In ceramic restored (Group II), an increase in Knoop microhardness (KHN) values was seen at 10-, 20-, and 40-day assessment with the respective values of 102.2 ± 20.3, 118.7 ± 19.4, and 127 ± 15.1. Similarly, a constant increase at different assessments was observed for Groups III and IV with 2% and 5% of mono-n-Dodecyl phosphate with ceramic with a 40-day KHN value of 128.2 ± 21.4 for Group III and 113.5 ± 17.3 for Group IV. A statistically significant difference was seen between ceramic and 5% mono-n-Dodecyl phosphate (Group IV) with hardness values of 30.31%, 29.8%, and 21.78% for Groups II, III, and IV, respectively, at 20 days. CONCLUSION: The present study concludes that ceramic restorations are effective in promoting dentin remineralization. However, the addition of only 2% mono-n-Dodecyl phosphate was beneficial, whereas 5% mono-n-Dodecyl phosphate reduced the efficacy of ceramic on dentin remineralization.

Assessment of different surface treatments and shear bond characteristics of poly-ether-ether-ketone: An in vitro SEM analysis.

Aim: The aim of this study is to assess the surface roughness and shear bond characteristics of pol-ether-ether-ketone after different surface treatments. Setting and Design: An in vitro, prospective. Materials and Methods: One hundred and twenty disc-shaped samples of 10 mm diameter and 2 mm thickness were milled and subjected to following surface treatments: 110 µm alumina particles, 98% concentrated sulfuric acid, and 10-20 µm synthetic diamond particles. Surface characteristics of treated sample were studied under SEM with ×500 and ×1000 magnification. Shear bond strength (SBS) with composite resin discs embedded in acrylic blocks after luting with self-etch resin cement and resin-modified glass ionomer cement (RMGIC) was evaluated using the universal testing machine (Instron®, Massachusetts U. S. A). Statistical Analysis Used: The data collected were evaluated using the Analysis of variance and Tukey's honest significant difference post hoc test. Results: Highest SBS and SR were noted with self-etch resin cement in the given order: 98% sulfuric acid (2.106 ± 0.186 µm), followed by alumina particles (1.706 ± 0.160 µm) and synthetic diamond particles (1.101 ± 0.167 µm). Conclusion: The SBS of self-etch resin cement was higher compared to RMGIC for all three surface treatments done on test samples. Hundred percent samples treated by all three surface treatment methods showed mixed type of failure.

An in vitro Comparative Evaluation of Micro Tensile Bond Strength of Two metal bonding Resin Cements bonded to Cobalt Chromium alloy.

BACKGROUND: The purpose of this study was to evaluate and compare the micro tensile bond strength of two metal bonding resin cements to sandblasted cobalt chromium alloy. MATERIALS & METHODS: Eight, Cobalt chromium alloy blocks of dimensions 10x5x5 mm were cast, finished and polished. One of the faces of each alloy block measuring 5x5mm was sandblasted with 50 µm grit alumina particles. The alloy blocks were then cleaned in an ultrasonic cleaner for 1 min and then air dried with an air stream. The Sandblasted surfaces of the two alloy blocks were bonded together with 2 different metal bonding resin systems (Panavia F Kuraray and DTK Kleber - Bredent). The samples were divided into 2 groups (n=4). Group 1- Two Co-Cr blocks were luted with Panavia cement. Group 2- Two Co-Cr blocks were luted with DTK Kleber-Bredent cement. The bonded samples were cut with a diamond saw to prepare Microtensile bars of approximately 1mm x 1mm x 6mm. Thirty bars from each group were randomly separated into 2 subgroups (n=15) and left for 3hrs (baseline) as per manufacturer's instructions while the other group was aged for 24hrs in 370C water, prior to loading to failure under tension at a cross head speed of 1mm/min. Failure modes were determined by means of stereomicroscopy (sm). Statistical analysis was performed through one way - ANOVA. RESULTS: Significant variation in micro-tensile bond strength was observed between the two metal bonding resin systems. CONCLUSION: DTK showed higher mean bond strength values than Panavia F cement both at baseline and after aging. How to cite this article: Musani S, Musani I, Dugal R, Habbu N, Madanshetty P, Virani D. An in vitro Comparative Evaluation of Micro Tensile Bond Strength of Two metal bonding Resin Cements bonded to Cobalt Chromium alloy. J Int Oral Health 2013;5(5):73-8.