Marginal microleakage of glass ionomer cement with two different cavity conditioners on primary anterior teeth - An in vitro study.

BACKGROUND AND OBJECTIVE: Glass ionomer cements (GICs) are the most commonly used restorative material in pediatric dentistry. They have numerous advantages; however, they show some marginal microleakage at the restoration-tooth interface. Various conditioning agents have been tested for alteration or dissolution of smear layer which has been attributed to the occurrence of microleakage; however, very limited studies have been done using primary teeth. AIMS: To evaluate and compare the effect of 10% polyacrylic acid and 17% EDTA on marginal microleakage of high-viscosity GIC. SETTINGS AND DESIGN: Experimental, in vitro study. METHODOLOGY: Class V cavities of standardized dimensions were prepared on 60 primary anterior teeth and were randomly divided into three groups. Except Group I, the cavities of Groups II and III were conditioned with 10% polyacrylic acid and 17% EDTA, respectively. All the 60 teeth were then restored with high-viscosity GIC. The samples were thermocycled and immersed in methylene blue solution for 24 h. The teeth were removed from the stain, rinsed, and sectioned buccolingually and were observed under stereomicroscope at 30× to score the marginal microleakage. STATISTICAL ANALYSIS USED: Kruskal-Wallis test followed by Mann-Whitney post hoc analysis were used to compare the mean marginal leakage scores between the three study groups. RESULTS: Statistical significance difference was found between all the three groups (P < 0.05). The mean marginal microleakage score was maximum for Group I (control group; 3.00), whereas it was the least for Group II (1.30) where 10% polyacrylic was used for conditioning the cavity surface. CONCLUSION: Among the study groups, none of them was completely devoid of microleakage in all its samples. 10% polyacrylic acid emerged as a better conditioning agent when compared with 17% EDTA in altering or removing the smear layer thereby resulting in better adhesion.

Evaluation of Relative Position of Mandibular Foramen in Children as a Reference for Inferior Alveolar Nerve Block using Orthopantamograph.

INTRODUCTION: The Mandibular Foramen (MF) is a landmark for administering local anaesthetic solution for Inferior Alveolar Nerve Block (IANB). The position of MF shows considerable variation among different ethnicity, ages and on either sides even within the same individual. Failure to achieve IANB leading to repeated injection of the local anaesthetic solution will not only pose a behaviour problem in children but can also lead to systemic toxic level of anaesthetic solution being administered. AIM: To determine the relative position of the mandibular foramen in 7 to 12-year-old children in relation to the mandibular occlusal plane and the deepest point on coronoid notch. MATERIALS AND METHODS: Ninety orthopantamograph of 7 to 12-year-old children were selected from the database and were divided into three groups: Group 1 (G1): seven to eight-year-old, Group 2 (G2): 9 to 10-year-old and Group 3 (G3): 11 to 12-year-old. The radiographs were traced on acetate paper, anatomical landmarks were marked and linear measurements were noted from the Mandibular Lingula (ML) to the occlusal plane, and to the deepest point on coronoid notch. The data obtained was tabulated and subjected to statistical analysis. One way ANOVA test followed by Bonferroni post hoc analysis and Student's paired t-test were used. RESULTS: Mandibular foramen is approximately, 2-3 mm above the occlusal plane and 11.6-13.0 mm from deepest point of coronoid notch for seven to eight-year-old children, 3-4 mm above the occlusal plane and 13.0-13.9 mm from deepest point of coronoid notch for 9-10 year age group and 5.5-6.5 mm above the occlusal plane and 11.9-12.2 mm from deepest point of coronoid notch for children of the ages 11-12 years. The linear distance from the deepest point of coronoid notch to the mandibular lingula showed statistical significance in G2 vs G3 on right side G1 vs G2 and G2 vs G3 on the left side. The variance of this distance for either side showed statistical significance for G1 and G2. CONCLUSION: The distance from the mandibular lingula to the occlusal plane showed gradual increase in all the three groups, which was statistically significant. The position of the mandibular foramen is not bilaterally symmetrically for any of the considered age groups.