Efficacy of protection by latex gloves during orthodontic therapy

Bacterial Count Comparisons on Examination Gloves from Freshly Opened Boxes Versus Nearly Empty Boxes and From Examination Gloves Before Treatment Versus After Dental Dam Isolation

Use of gloves in dentistry is primarily for protection of the healthcare worker, yet little information is available regarding potential patient issues such as microbial contamination of gloves before and during use. The purposes of this study were to compare gloves from newly opened boxes with those from boxes that had been in dental operatories until they were nearly empty and to determine if gloves are contaminated though diagnostic procedures and rubber dam placement. Eight endodontic residents provided samples by streaking gloved fingers on nutrient agar plates. Results showed no statistically significant difference between counts from new boxes versus nearly empty boxes (n = 32, p < 0.6216). Gloves after rubber dam placement yielded a mean colony count of 158 versus a 1.5 mean of fresh gloves (n = 64, p < 0.0001). These results suggest that the use of new gloves before opening a tooth for endodontic therapy may be warranted.

Biaxial flex-fatigue and viral penetration of natural rubber latex gloves before and after artificial aging

Barrier integrity of unaged and oven-aged (at 70 degrees C) natural rubber latex examination gloves was assessed with a biaxial flex-fatigue method where failure was detected electronically, and by live viral penetration testing performed according to a modified version of ASTM F1671-97a. When no change in barrier properties was detected during flex testing, no virus passage was found after viral challenge. Conversely, when a change in the barrier properties was indicated by the electrical signal, virus passage was found in 74% of the specimens. Flex-fatigue results indicated that unaged test specimens from powdered (PD) and powder-free (PF) nonchlorinated gloves had significantly longer fatigue lives than powder-free chlorinated (CL) gloves from the same manufacturer. Biaxial flexing of oven-aged glove specimens showed a marginal increase in fatigue life for the PF gloves, but no increase for the PD gloves. The fatigue life of the CL gloves was observed to increase significantly after oven aging. However, this appears to be due to a design feature of the test apparatus, wherein peak volume displacement of the worked specimen is held constant. An aging-induced change in the viscoelastic properties of the CL gloves-permanent deformation of the specimens early in the fatigue test-relieves the stress magnitude applied as the test progresses. Thus, permanent deformation acts as a confounding factor in measuring durability of latex gloves by fixed displacement flex-fatigue.

Abrasion resistance of medical glove materials

Due to the increasing demand for nonlatex medical gloves in the health-care community, there is a need to assess the durability of alternative glove materials. This study examines durability characteristics of various glove materials by abrasion resistance testing. Natural rubber latex (latex), polyvinyl chloride (vinyl), acrylonitrile butadiene (nitrile), polychloroprene (neoprene), and a styrene-ethylene/butylene-styrene block copolymer (SEBS) were tested. All test specimens, with the exception of the vinyl, were obtained from surgical gloves. Unaged out-of-the-box specimens as well as those subjected to various degrees of artificial aging were included in the study. After the abrasion sequence, the barrier integrity of the material was assessed through the use of a static leak test. Other traditional tests performed on these materials were viral penetration to validate the abrasion data and tear testing for comparative purposes. The results indicate that specific glove-material performance is dependent upon the particular test under consideration. Most notably, abrasion, even in controlled nonsevere conditions, may compromise to varying degrees the barrier integrity of latex, vinyl, SEBS, nitrile, and neoprene glove materials. However, as evidenced by the results of testing three brands of neoprene gloves, the abrasion resistance of any one glove material may be significantly affected by variations in production processes.