Comparative Evaluation of Fracture Toughness and Flexural Strength of Four Different Core Build-up Materials: An In Vitro Study.

AIM: To evaluate and compare the fracture toughness and flexural strength of four different core build-up materials. MATERIALS AND METHODS: A total of 60 samples were divided into four groups (n = 15) group I: dual cure composite resin reinforced with zirconia particles (Luxacore Z), group II: light cure composite resin (Lumiglass DeepCure), group III: zirconia reinforced glass ionomer cement (GIC) (Zirconomer Improved), and group IV: chemically cure composite resin (Self Comp) respectively. All the core build-up materials were manipulated according to the manufacturer's instructions and poured into the mold. A universal testing machine applied a central load to the specimen in a 3-point bending mode. Fracture of the specimen was identified and the reading was recorded by the universal testing machine. The data were analyzed statistically using one-way analysis of variance (ANOVA) and then compared. RESULTS: Group I showed the highest flexural strength (48.65 MPa) among all the groups while group IV showed the lowest flexural strength (17.90 MPa). Group I showed the highest fracture toughness (99.12 MPa) among all the groups while group IV showed the lowest fracture toughness (36.41 MPa.cm-0.5). When mean flexural strength and fracture toughness values of all four groups were compared by using one-way ANOVA, the compared data was highly significant. CONCLUSION: Based on the findings of this study, dual cure composite resin was the material of choice in terms of flexural strength and fracture toughness for core build-up material followed by light cure composite resin. CLINICAL SIGNIFICANCE: The core buildup material serves to strengthen the tooth structure, allowing it to withstand the forces of chewing and preventing the risk of tooth fractures. This material is essential in restoring damaged or decayed teeth, as it provides a stable foundation for further dental work. By reinforcing the tooth structure, the core buildup material ensures that the tooth can function properly and remain healthy for years to come. How to cite this article: Nakade P, Thaore S, Bangar B, et al. Comparative Evaluation of Fracture Toughness and Flexural Strength of Four Different Core Build-up Materials: An In Vitro Study. J Contemp Dent Pract 2024;25(2):191-195.

Bond Strength of Orthodontic Brackets to Temporary Crowns: In vitro Effects of Surface Treatment.

Background: To evaluate bond strength of orthodontic brackets to temporary crowns. Materials and Methods: A bis-acrylic composite was used to create a total of 25 discs, which were then divided into five groups based on how their surfaces were treated with black, blue, green, and sandblasted diamond burs, in addition to a control group. Software called SPSS was used to analyze the outcome. Results: The average pressures measured for the green bur, black bur, and sandblasting, respectively, were 12.05 MPa, 12.87 MPa, and 19.25 MPa. Comparing the control and blue groups, a substantial variation in shear bond strength was only noticed with reference to sandblasting. Conclusion: The binding strength of orthodontic brackets is increased by sandblasting temporary crowns.

Radiomorphometric Indices and their Relation to Alveolar Bone Loss: A Panoramic Radiographic Study.

Aim: To assess the influence of gender and age on different parameters of alveolar bone loss using specific radiomorphometric indices on panoramic radiographs to aid in identifying patients with possible low bone mineral density (BMD). Materials and Methods: The present cross-sectional study included 80 subjects in whom mandibular cortical index (MCI), mandibular cortical width (MCW), panoramic mandibular index (PMI), alveolar bone loss (ABL), and bone height in 1st premolar (Hp) and 1st molar (Hm) were assessed to evaluate the alveolar bone loss. Results: The findings of the present study revealed a significant association between MCI and age for females with C2 and C3 categories being more common with advancing age. Also, a significant difference could be seen in relation to gender (p-value = 0.0315) for MCW with a concomitant decrease in values of MCW in females >60 years of age. The vertical bone height of the edentulous mandible at 1st premolar (Hp) (p-value = 0.0071) and 1st molar (Hm) (p-value = 0.0044) regions were also found to be more in males than females. Conclusion: Panoramic radiographic measurements provided valuable information for alveolar bone loss in terms of gender and age based on specific radiomorphometric parameters.

Assessment of the Effect of Complete Dentures on Respiratory Performance: A Spirometric Analysis.

BACKGROUND: Among the vital functions, respiration can be claimed to be one of the most important. A thorough understanding of the patient should be an important aspect a prosthodontist should dwell into so as to predispose patients to acknowledge the kind of prosthesis they require. Hence, the present study was conducted for assessing the effect of complete dentures on respiratory performance. MATERIALS AND METHODS: Fifty patients with the presence of complete edentulous arch and who had a history of complete denture usage for at least 5 years were enrolled. All the spirometric procedures were performed by trained technicians. A diagnostic spirometer was employed for performing the spirometric test. Testing was carried out in the following steps: Stage 1: testing in the absence of denture, Stage 2: testing in the presence of both dentures, Stage 3: testing in the presence of maxillary denture only, and Stage 4: testing in the presence of mandibular dentures only. Forced vital capacity (FVC) value, peak expiratory flow (PEF) value, forced expiratory volume in 1 s (FEV1) value, and forced expiratory flow 25%-75% (FEF25-75) value were recorded with the spirometric test. Analysis of all the results was done by SPSS software. RESULTS: The spirometric value of FVC, PEF, FEV1, and FEF25-75 in the absence of both maxillary and mandibular dentures (Stage 1) was found to be 3.18, 5.83, 2.44, and 2.80, respectively. The spirometric value of FVC, PEF, FEV1, and FEF25-75 in the presence of both maxillary and mandibular dentures (Stage 2) was found to be 3.09, 5.67, 2.41, and 2.67, respectively. While analyzing statistically, it was seen that there was a significant decrease in the value of spirometric variables in the presence of dentures. CONCLUSION: Chronic denture wearer edentulous patients are subjected to the risk of development of spirometric alterations. Hence, these patients should be given timely instructions about the various respiratory exercise protocols.