RESUMO
BACKGROUND The present study aimed to compare the clinical performance and gingival sulcus width changes in partially edentulous patients using cotton and polymer gingival retraction cords. MATERIAL AND METHODS Fifty partially edentulous patients were divided into 2 groups (Gp C and Gp P) and were subjected to single crown/fixed partial denture treatment. Clinical parameters, including plaque index scores, placement time, and hemorrhage control scores, were assessed. Gingival sulcus width changes before and after retraction were evaluated using individual type 4 dental stone dies observed under an optical microscope. Statistical analysis was performed using dependent/independent t tests. RESULTS The mean placement time, hemorrhage control time, and hemorrhagic scores were lower in Gp P than in Gp C, indicating better clinical performance of polymer-based retraction cord. Both groups showed an increase in sulcus width after retraction, but Gp P had a significantly higher sulcus width (690.03±45.37) compared to Gp C (471.38±28.13). The mean difference in sulcus width between baseline and after retraction was also significantly higher in Gp P (525.84 micrometers) than in Gp C (309.11 micrometers). CONCLUSIONS The present study shows that polymer-based cords produce more sulcus width and have better clinical performance compared to cotton-based gingival retraction cords. These results suggest that the use of polymer-based retraction cords can improve the quality of dental impressions in partially edentulous patients.
Assuntos
Gengiva , Polímeros , Humanos , Coroas , HemorragiaRESUMO
AIM: The present study aimed to evaluate the alteration in the compressive strength (CS) of the die stone with three different sulfate salt additives, each at eight various concentrations. MATERIALS AND METHODS: The specimens were prepared at specific dimensions (length: 2.5 cm and diameter: 2.5 cm) divided into three test groups based on the type of sulfate additives used [potassium sulfate (K2SO4), zinc sulfate (ZnSO4·H2O), and manganese sulfate (MnSO4·H2O)] and one control group, without any additives. Again, each group was divided into eight subgroups based on concentration of sulfates (ranging from 0.2% to 4%). A total of 375 specimens were tested. CS (in MPa) was evaluated after 72 hours of drying time, using an universal testing machine. STATISTICAL ANALYSIS: A one-way analysis of variance (ANOVA) was used for intergroup comparisons. Individual comparisons were done using the post hoc Tukey HSD analysis. RESULTS: All the three additives at all the concentrations have shown an inferior resistance to compressive forces when compared to the standard specimen. However, the least mean CS was observed at 0.8% of MnSO4 (10.95 MPa) and the highest was at 1% K2SO4 (25.28%). A highly significant difference (p < 0.001) was observed among the concentrations in all the three groups (K2SO4, MnSO4, and ZnSO4 groups) and F values were derived as 69.84, 24.29, and 130.52, respectively. At each concentration, comparisons between the groups have shown a significant difference (p < 0.05) at almost all concentrations. CONCLUSION: The CS of die stone is shown to be decreased with an increase in all three types of sulfate additives when compared to the control specimen. CLINICAL SIGNIFICANCE: Die stone is an often used gypsum material in the field of dentistry. Compressive strength of the die stone is crucial in prosthetic dentistry; chemical additives such as sulfate salts may increase the CS such that the die stone can withstand clinical and laboratory handling forces. How to cite this article: Vyas R, Vaddamanu SK, Gurumurthy V, et al. Variations in the Compressive Strength of a Die Stone with Three Different Sulfates at Eight Different Concentrations: An In Vitro Study. J Contemp Dent Pract 2019;20(11):1297-1306.
