Power brushing and chemical denture cleansers induced color changes of pre-polymerized CAD/CAM denture acrylic resins

Abstract

Denture wearers are advised to follow the protocol of using both mechanical and chemical hygiene methods. In this study, the in-vitro color stability of heat-cured, light-cured and newly developed pre-polymerized CAD/CAM acrylic resin base materials were evaluated after exposure to mechanical brushing and chemical denture cleansers. Two polymethyl methacrylate (PMMA) (heat-cured, and pre-polymerised CAD/CAM) and one urethane dimethacrylate based resin denture base material were subjected to mechanical brushing, followed by immersion in chemical denture cleansers (Corega, 5.25% Sodium hypochlorite (NaOCl), and 0.2% chlorhexidine gluconate (CHG)) and thermal-cycling to simulate one-year of normal prosthesis use. Baseline and final color measurements were determined and the difference in color was calculated using bench-top UV light visible spectrophotometer. The highest (29.69 ± 1.84) and lowest (19.03 ± 8.78) mean ΔE was observed with light-cured and CAD/CAM materials immersed in 0.2% CHG, respectively. Tukey’s post-hoc test showed that heat cured and light-cured resins immersed in either of the denture cleansers showed no significant differences (p > 0.05) in the mean ΔE values. On the contrary, CAD/CAM materials immersed in either of the denture cleansers demonstrated significant differences in the mean ΔE values (p ≤ 0.05). A statistically significant interaction between the combination of materials and denture cleansers (F = 4.890; p = 0.001) was observed. The color stability of the pre-polymerized CAD/CAM acrylic discs is comparatively better than the conventional acrylic resin materials. The changes in the color values of all the tested materials were above the clinically acceptable range, regardless of the type of denture cleanser used.

Pros and Cons of CAD/CAM Technology for Infection Prevention in Dental Settings during COVID-19 Outbreak

“…The milled group displayed promising potential for reducing the adherence of Candida [ 69 ]. Because of the ban on glutaraldehyde to avoid work risk in the EU, chlorhexidine digluconate is the best choice in terms of avoiding changes in roughness and colour changes in CAD/CAM materials [ 132 ], compared to conventionally fabricated acrylic resin [ 133 ]. The use of povidone iodine or sodium hypochlorite, generically indicated by the CDC during phase I and II, has not been supported by scientific evidence for SARS-CoV-2 prevention and compatibility with acrylic appliances [ 134 ].…”

Thermal-cycling, simulated brushing, and beverages induced color changes and roughness of CAD/CAM poly (methyl methacrylate) denture resins

“…In CIEL * a * b * , L * represents light and dark on a scale and ranges from 0 (black) to 100 (white), a * and b * are on the chromatic scale: a * corresponds with red (+), and green (−) quantity and b * corresponds with yellow (+), and blue (−) quantity [22]. Three recordings were obtained for each specimen at baseline and after surface treatment, and the mean ΔE was calculated using the following equation (1).…”

“…Poly (methyl methacrylate) (PMMA) resin has gained tremendous consideration due to its unique properties: low density, acceptable aesthetics, cost-effectiveness, ease of manipulation, and good physical and mechanical properties [1]. They have been used for more than 80 years and are still considered gold-standard to fabricate complete dentures (CD).…”

Efficacy of Denture Cleansers on Microbial Adherence and Surface Topography of Conventional and CAD/CAM-Processed Denture Base Resins

“…Denture hygiene maintenance involves either mechanical or chemical, or a combination of both, methods [ 19 , 20 ]. Mechanical cleaning by brushing is a simple, easy, and cost-effective method for reducing denture biofilm; however, improper brushing can cause wear of the denture base material, leading to surface defects on the surface of the denture, which promotes bacterial colonization and pigmentation [ 19 , 21 ]. Furthermore, patients with low manual dexterity, especially geriatric and physically compromised patients, may find it difficult to practice the mechanical hygiene method [ 22 ].…”

“…An ideal chemical denture cleanser should inhibit or reduce the accumulation of biofilms; possess antifungal and antibacterial activity; have a pleasant odor; and be inexpensive, easy to use, and non-toxic [ 17 , 21 , 23 , 24 , 25 , 26 , 27 ]. The importance of these treatments being efficient against microorganisms while also having minimal negative impacts on the physical and mechanical properties of the denture cannot be overstated [ 19 , 21 , 28 ]. Over the years, varieties of disinfectants have been employed successfully to limit bacterial growth and Candida species adhesion to denture surfaces.…”