Latex and non-latex orthodontic elastic force loss due to cyclic temperature.

UNLABELLED: The purpose of this study was to compare the force loss of 1/4 inch (6.35mm) 3.5oz (99g) medium latex elastics from Ormco Corp. to non-latex elastics from ClassOne Orthodontics and Phoenix after being cycled between different temperatures. Elastics were stretched to 1.57 inches (40mm) on jigs and cycled in water baths for 4 minutes at 5 degrees C and 37 degrees C, 21 degrees C and 37 degrees C, 5 degrees C and 50 degrees C, 37 degrees C and 50 degrees C, and a control group was held at 3 degrees 7 degrees C. The force produced by new elastics and elastics after incubation was measured using a Mini 44 Instron. RESULTS: All elastics experienced increased force loss that correlated with increased temperatures with the exception of Ormco latex elastics. The latex elastics had the greatest force loss upon cycling between 5 degrees C and 50 degrees C while the non-latex elastics had the greatest force loss while cycling between 37 degrees C and 50 degrees C. All elastics were strongest when cycled between 5 degrees C and 37 degrees C. CONCLUSION: This study suggests that hot liquids reduce the force of latex and non-latex elastics even when cycled between hot temperatures for brief periods of time.

Bond strength comparison of color change adhesives for orthodontic bonding.

This study investigated whether three different color change light-cured orthodontic bonding adhesives have comparable shear bond strengths to a conventional light-cured orthodontic bonding adhesive. The sample of 240 bovine incisors was divided into four groups of 60 each. Each group tested one of four orthodontic bonding adhesives: 3M Unitek Transbond PLUS, Ormco Gréngloo, Ormco Blúgloo, and 3M Unitek Transbond XT (control). The four groups were further divided into two subgroups of 30 with shear bond strength tested at two different times (15 minutes and 24 hours) post-bond. The shear bond strength was measured on a universal testing machine. The data were analyzed by two-way analysis of variance and post-hoc comparisons (Fisher's PLSD) at the 0.05 level of significance. The average shear bond strength was greater at 24 hours than at 15 minutes for Transbond PLUS, Blúgloo, and Transbond XT. For Gréngloo, the average shear bond strength was greater at 15 minutes than at 24 hours. Gréngloo tested at 15 minutes had the highest average shear bond strength. Gréngloo tested at 24 hours had the lowest average shear bond strength. All four orthodontic bonding adhesives demonstrated bond strengths considered to be clinically acceptable for orthodontic purposes.

Force relaxation between latex and non-latex orthodontic elastics in simulated saliva solution.

UNLABELLED: The aim of this study was to compare the force relaxation between traditional latex elastics to different brands of non-latex elastics in a simulated saliva solution. The force relaxation of 6.35 mm (0.25 inch), 99 g (3.5 oz), non-colored latex elastics from Ormco Corp. and non-latex elastics from Phoenix Orthodontics, ClassOne Orthodontics, and Glenroe was tested. The elastics were stretched to 40 mm (1.57 inch) and the force produced by the elastics was then measured using a Mini 44 Instron machine. RESULTS: The latex elastics had an initial relaxation of 15 percent after 1 hour of incubation and maintained their reduced force after 24 hours of incubation. Non-latex elastics lost approximately 20 percent of their force after the first hour and continued to lose force after up to 24 hours of incubation resulting in as much as 48 percent force relaxation. CONCLUSION: Latex elastics should be used whenever possible; however, when non-latex elastics are warranted, the clinician should take into account their greater initial forces, significant force relaxation, and variability among brands.

Salivary analysis in the diagnosis and treatment of breast cancer: a role for the general dentist.

Saliva testing is an attractive area of research for the general dentist, as it offers a great opportunity to utilize an easily accessible fluid for the diagnosis of disease. Diseases that may be difficult to detect, such as breast cancer, are an area of particular interest. Breast cancer is the second leading cause of death among women in the U.S. and early detection is critical to patient survival. Frequent and inexpensive testing is the key to early detection. The general dentist is in the perfect position to take salivary samples from patients during routine checkups or procedures and to refer patients depending on the results.