Relationship between Body Fat and Masticatory Function

Purpose: The aim of this cross-sectional study was to investigate the relationship between body fat and masticatory function. Materials and Methods: One hundred dentate and partially edentulous participants (33 male; mean age, 39.7 +/- 16.6 years) were selected. Body fat was established through body mass index (BMI). Masticatory function was evaluated by quantifying occlusal pairs and determining masticatory efficiency and swallowing threshold with the sieving method. During the swallowing threshold test, chewing rate was registered. Masticatory ability was also evaluated with a 5-point Likert scale questionnaire. Data were analyzed with Spearman and chi-square tests, as well as binary logistic regression analysis for the presence of increased BMI (= 0.05). Results: Age (rho = 0.517), occlusal pairs (chi-square = 26.353), masticatory efficiency (chi-square = 30.935), masticatory ability (chi-square = 25.132; p < 0.001), and swallowing threshold (chi-square = 8.730; p < 0.005) were related to BMI. Age (odds ratio, OR = 1.048, 95% CI = 1.008 to 1.089) and lower masticatory efficiency (OR = 4.792, 95% CI = 1.419 to 16.183) were predictive of increased body fat (p < 0.05). Gender (chi-square = 0.402, p= 0.526) and chewing rate (rho =0.158, p= 0.117) were not related to BMI. Conclusions: These results suggest that people with lower masticatory efficiency may be at risk for increased body fat.22212012

Mastication in Subjects with Extremely Shortened Dental Arches Rehabilitated with Removable Partial Dentures

Mastication was evaluated in subjects presenting extremely shortened dental arches (ESDAs) rehabilitated with mandibular free-end removable partial dentures (RPDs). Subjects were divided into four groups (n = 10): those with a complete dentition, those with ESDAs, and those with ESDAs who were rehabilitated with an RPD, who were evaluated both with and without their prostheses. Mastication was measured through masticatory performance, time, and ability. RPD wearers showed higher masticatory performance (P <.01) and ability (P <.001) and lower masticatory time (P <.001) than when not wearing their prostheses as well as ESDA subjects who had not received RPD therapy. Those with a complete dentition showed the best results (P <.001). It can be suggested that RPDs improve mastication in ESDA subjects but without achieving normal mastication levels. Int J Prosthodont 2011;24:517-519.24651751

Effect of storage in water and thermocycling on hardness and roughness of resin materials for temporary restorations

PURPOSE: This study evaluated the effect of storage in water and thermocycling on hardness and roughness of resin materials for temporary restorations. MATERIAL AND METHODS: Three acrylic resins (Dencor-De, Duralay-Du, and Vipi Cor-VC) were selected and one composite resin (Opallis-Op) was used as a parameter for comparison. The materials were prepared according to the manufacturers' instructions and were placed in stainless steel moulds (20 mm in diameter and 5 mm thick). Thirty samples of each resin were made and divided into three groups (n = 10) according to the moment of Vickers hardness (VHN) and roughness (Ra) analyses: C (control group): immediately after specimen preparation; Sw: after storage in distilled water at 37 °C for 24 hours; Tc: after thermocycling (3000 cycles; 5-55 °C, 30 seconds dwell time). Data were submitted to 2-way ANOVA followed by Tukey's test (&#945; = 0.05). RESULTS: Op resin had higher surface hardness values (p < 0.0001; 25.4 ± 3.4) than the other ones (De = 4.5 ± 0.6; Du = 5.5 ± 0.4; VC = 6.1 ± 0.9). There was no statistical difference (p > 0.05) in roughness among materials (De = 0.31 ± 0.07; Du = 0.51 ± 0.20; VC = 0.41 ± 0.15; Op = 0.42 ± 0.18). Storage in water did not change hardness and roughness of the tested materials (p > 0.05). There was a significant increase in roughness after thermocycling (p < 0.05), except for material Du, which showed no significant change in roughness in any evaluated period (p = 0.99). CONCLUSION: Thermocycling increased the roughness in most tested materials without affecting hardness, while storage in water had no significant effect in the evaluated properties