Biofilm accumulation on additive manufactured Ti-6Al-4V alloy surfaces.

Purpose: This study investigated whether additive manufactured (AM) surfaces inhibit accumulation of bacterial biofilm on the surfaces of Ti-6Al-4V alloy dental implants. Bacterial biofilms are thought to cause peri-implant disease, which develops in mucosa surrounding titanium (Ti) and Ti alloy dental implants and can lead to bone loss and implant failure.

Methods: Accumulation of a Streptococcus mutans (ATCC 25175) biofilm on Ti-6Al-4V alloy was compared in relation to fabrication method, ie, AM using electron beam melting (EBM) or laser beam melting (LBM).

Fabrication of titanium removable dental prosthesis frameworks with a 2-step investment coating method.

Statement Of Problem: Although pure titanium is known to have good biocompatibility, a titanium alloy with better strength is needed for fabricating clinically acceptable, partial removable dental prosthesis (RDP) frameworks.

Purpose: The mechanical properties of an experimental Ti-5Al-5Cu alloy cast with a 2-step investment technique were examined for RDP framework applications.

Material And Methods: Patterns for tests for various properties and denture frameworks for a preliminary trial casting were invested with a 2-step coating method using 2 types of mold materials: a less reactive spinel compound (Al(2)O(3)·MgO) and a less expensive SiO(2)-based material.

Comparison of the flexural strength of five adhesive resin cements.

Statement Of Problem: The increased use of adhesive resin cements in bonded prosthetic restorations has led to restorations debonding under function.

Purpose: This investigation evaluated the differences in the flexural strength of new adhesive resin cements as a function of specimen age and storage condition.

Materials And Methods: Four new dual-cure cements were compared to C/B Metabond.

Conserving old-growth forest diversity in disturbance-prone landscapes.

A decade after its creation, the Northwest Forest Plan is contributing to the conservation of old-growth forests on federal land. However the success and outlook for the plan are questionable in the dry provinces, where losses of old growth to wildfire have been relatively high and risks of further loss remain. We summarize the state of knowledge of old-growth forests in the plan area, identify challenges to conserve them, and suggest some conservation approaches that might better meet the goals of the plan.

Quality of removable partial dentures worn by the adult U.S. population.

Statement Of Problems: Research-based assessments of the quality of removable partial dentures (RPDs), especially within a large patient population, are lacking.

Purpose: This study evaluated the prevalence and quality of RPDs by use of the National Health and Nutrition Survey (NHANES III) data set.

Material And Methods: Estimates of the health and nutritional status of the American population were obtained from the NHANES III data set (1988-1994).