Tooth size and dental arch dimensions: a stereophotogrammetric study in Southeast Asian Malays.

OBJECTIVE: To investigate tooth size and dental arch dimensions in Malays using a stereophotogrammetric system. SETTING AND SAMPLE POPULATION: The sample consisted of 252 subjects with ages ranged from 13 to 30 years. MATERIALS AND METHODS: Images of dental casts were captured by stereophotogrammetry and selected variables were measured using a three-dimensional (3D) imaging system. Sex differences and changes associated with age were assessed, and interrelationships between different variables were explored within the study group. RESULTS: Men had significantly larger mesio-distal crown widths and dental arch dimensions than women (p < 0.05). None of the dental arch dimensions or mesio-distal crown widths showed a significant change because of age except the widths of the upper canine, lower first molar and central incisor. Significant correlations of tooth size with dental arch dimensions were found, particularly with arch lengths and perimeters. A principal component analysis showed interrelationships between the majority of tooth size variables with inter-canine width, arch length and perimeter distances. CONCLUSION: This study has established new reference data for tooth size and arch dimensions in Malays and demonstrated patterns of variation that are relevant to anthropologists interested in making comparisons within and between different populations and also to clinicians developing treatment plans for their patients. The study confirmed the accuracy of the 3D photogrammetric method for measuring dental casts.

Effect of Ramadan fasting on serum heat shock protein 70 and serum lipid profile.

INTRODUCTION: Ramadan, the holy month for the Islamic world, is a period every year when food and fluid intake is restricted to the pre-sunrise and post-sunset hours. The aim of this study was to evaluate the effect of Ramadan fasting on the serum concentration of heat shock protein 70 (HSP70) and serum lipid profile in healthy men. METHODS: A total of 32 male volunteers with a mean age of 28.5 (range 23-37) years were selected for the study. Blood samples were obtained one day prior to Ramadan and on the 3rd and 25th days of fasting. Serum HSP70, triglyceride (TG), cholesterol (Chol), low-density lipoprotein (LDL) and high-density lipoprotein (HDL), LDL/HDL and Chol/HDL ratios were investigated. RESULTS: It was observed that the mean concentrations of serum HSP70 and HDL on the 25th day of Ramadan were significantly higher than those recorded one day before Ramadan and on the 3rd day of Ramadan, and the levels on the 3rd day of Ramadan was significantly higher than those recorded one day before Ramadan. Mean concentrations of serum TG, Chol, LDL, and LDL/HDL and Chol/HDL ratios on the 25th day of Ramadan were significantly lower than those recorded one day before Ramadan and on the 3rd day of Ramadan, and the levels found on the 3rd day of Ramadan were also significantly lower than those recorded one day before Ramadan. CONCLUSION: Ramadan fasting increases serum HSP70 and improves serum lipid profile.

Effect of desensitizing agent on shear bond strength of an adhesive system

Desensitization of teeth after cavity preparation has been recommended in an attempt to avoid post-operative sensitivity. However, there is concern regarding application effect of desensitizing agent on shear bond strength of the adhesive system used. The purpose of our study was to compare the shear bond strength of adhesive system in two different dentin surface treatments, with and without desensitizing agent. Sixteen extracted human premolars were sectioned off at the coronal portion to expose the flat dentin surfaces. The surfaces were finished using 600 Grit Wet Silicon Carbide abrasive papers. The premolars were randomly assigned to two groups: control and treated with MS Coat desensitizing agent. The desensitizer was applied according to manufacturer’s instruction. Resin composite was bonded to each dentin surface using Prime & Bond® adhesive system. The composite resin was debonded by shear stress. Mann-Whitney Test was used in statistical analysis. Our result showed that application of MS Coat desensitizing agent on dentin surface had significantly reduced the shear bond strength of the adhesive system used (z = - 0.14, p < 0.05). Thus, we conclude that shear bond strength of Prime & Bond® NT (Dentsply, USA) adhesive system will be reduced if dentin surface is treated with MS Coat (Sun Medical, Japan) desensitizing agent.