SETTINGS AND DESIGN: A cross-sectional multi-national, multi-centric correlation trial.
MATERIALS AND METHODS: A cross-sectional study was conducted in India and Malaysia with a total of 688 participants. Measurements of thumb and VDR were obtained using a modified Willi's gauge using a standard operating procedure.
STATISTICAL ANALYSIS USED: Pearson's correlation coefficient was calculated to determine the correlation between TL and VDR. A multiple linear regression was done to correlate VDR from gender, orthodontic treatment, and length of thumb.
RESULTS: Correlation coefficient between TL and VDR in patients with orthodontic treatment was 0.829 and 0.774 in patients without orthodontic treatment. The correlation between TL and VDR in patients with orthodontic treatment in North India was 0.484, P = 0.010 and Malaysia was 0.946, P < 0.001. There were significant correlations between TL and VDR in patients without orthodontic treatment in all regions (P < 0.001). Regression equations were obtained for different ethnic groups for calculating the VDR.
CONCLUSION: There was an overall positive correlation between TL and VDR in patients with and without orthodontic treatment. The regression equations presented in this article could help clinicians in their clinical practice and researchers to conduct future trials.
Setting and Design: In vitro - Comparative study.
Materials and Methods: Denture base adaptation of two different rapid heat-cured polymethyl methacrylate acrylic resins using five different cooling methods were compared. Forty maxillary edentulous stone cast were prepared to produce the denture bases with standardized thickness. The specimens were divided into five groups (n = 8) according to type of materials and cooling methods. The master stone cast and all forty denture bases were scanned with 3Shape E1 laboratory scanner. The scanned images of each of the denture bases were superimposed over the scanned image of the master cast using Materialize 3-matic software. Three dimensional differences between the two surfaces were calculated and color surface maps were generated for visual qualitative assessment.
Statistical Analysis Used: Generalized Linear Model Test, Bonferroni Post Hoc Analysis.
Results: All bench-cooled specimens showed wide green-colored area in the overall palatal surface, while the rapid cooled specimens presented with increased red color areas especially at the palate and post dam area. Generalized Linear Model test followed by Bonferroni post hoc analysis showed significant difference in the root mean square values among the specimen groups.
Conclusion: Samples that were bench cooled, demonstrated better overall accuracy compared to the rapid cooling groups. Regardless of need for shorter denture processing time, bench cooling of rapid heat-cured PMMA is essential for acceptable denture base adaptation.
MATERIALS AND METHODS: The processing technique described the incorporation of the preshaped "wax-bolus" during packing procedure of the Obturtor prosthesis and eliminated later by melting it once the curing procedure is completed.
RESULTS: This article is a single step procedure resulting into the closed-hollow obturator as single unit with uniform wall thickness around the hollow space ensuring the least possible weight of the hollow obturator.
CONCLUSION: This processing technique achieves predictable internal dimension of the hollow space providing uniform wall thickness of the obturator.