Effectiveness of disinfectant solutions associated or not with brushing on the biofilm control of a 3D printed-denture base resin

Abstract

The formation of biofilm on denture bases is a recurrent clinical problem that favors the development of denture stomatitis. The effectiveness of a hygiene protocol in a 3D-printed denture base resin is still uncertain. Objective To evaluate of the effectiveness of immersion, associated or not with brushing in a soap solution, on the biofilm control of a 3D-printed denture base resin. Methodology Specimens of denture base resins [Cosmos Denture (COS) and Classico (CLA/control)] were contaminated in vitro with Candida albicans and immersed in sodium hypochlorite 0.25% (SH, alkaline peroxide) AP, chlorhexidine digluconate 2% (CD or PBS-Control), associated or not with brushing with 0.78% Lifebuoy soap. Roughness was evaluated before and after brushing and immersion. The effectiveness of the protocols was assessed by CFU/mL, cellular metabolism (XTT), scanning electron microscopy (SEM), and confocal scanning laser microscopy. Data were analyzed by T student, ANOVA/Welch, and Tukey/Gomes–Howell pos-hoc tests (α = 0.05). Results CLA showed greater roughness than COS. CFU/mL and XTT were higher in COS resin with a higher hyphae formation. Immersion in SH and CD eliminated CFU/mL and reduced XTT for both resins, associated or not with brushing. AP reduced CFU/mL only when associated with brushing. Conclusions The biofilm on the 3D-printed resin was thicker and presumably more pathogenic, regardless of its smoother surface. Immersions in SH 0.25% and CD 2% are effective hygiene protocols for both resins, associated or not with brushing. AP should be recommended when associated with brushing with a Lifebuoy 0.78% solution.

Strategies for Preventing and Treating Oral Mucosal Infections Associated with Removable Dentures: A Scoping Review

“…In addition to the development of products and methods that aim to reduce the microbial load and prevent DRS, technological development also provides new materials for application in the manufacture of prostheses, such as additive manufacturing (printed) and subtractive manufacturing resins. Aiming to evaluate the behavior of these materials in the face of biofilm formation, and their physical–mechanical behavior when exposed to different environmental factors and hygiene protocols, some in vitro studies have been carried out [ 116 , 129 , 130 , 131 , 132 , 149 ].…”

“…In another study, C. albicans adhesion was investigated and it was found that the propensity for fungal biofilm attachment varies among different resin types, with a higher tendency observed for 3D-printed resin surfaces [ 129 ]. Studies that evaluated Candida albicans formation in different types of resins, such as thermopolymerized PMMA/conventional resin, and milled and printed resins, demonstrated greater adhesion, higher counts of colony-forming units, and the formation of Candida albicans hyphae in printed resins compared to conventional and milled resins [ 129 , 131 , 132 ]. Furthermore, as printed resins present physical–mechanical changes compared to conventional resins, it is recommended to use printed resins for the manufacture of denture bases for temporary rehabilitative treatments that are restricted to less than 3 years [ 149 ].…”

Anti-biofilm effectiveness of protocols for cleaning complete dentures in hospitalized patients: a randomized controlled trial

“…The selection of concentrations, immersion time, and brushing protocols used with chlorhexidine solutions was carried out based on the antimicrobial effectiveness demonstrated by in vitro 15 , 17 , 18 , 20 , 22 , 24 , 27 and in vivo studies. 23 , 25 In this investigation, brushing with 2% chlorhexidine (BRU/CHX-2) proved as effective as protocols that used hypochlorite solution.…”

“…Chlorhexidine 0.12% (CHX-0.12), regardless of the association with brushing, showed a significant reduction in its ability to reduce the microbial load and the denture biofilm coverage area. This antiseptic has distinct effects at different concentrations, which vary between microbial species, with bactericidal/fungicidal action at higher concentrations 17 , 18 , 22 and bacteriostatic action at low concentrations. 17 , 27 , 43…”

“…Experimental groups used cleaning solutions of 1% sodium hypochlorite, 0.12% and 2% chlorhexidine digluconate (Rioquimica Indústria Farmacêutica S/A, São José do Rio Preto, SP, Brazil), alkaline peroxide tablets (Corega Tabs, GlaxoSmithKline Brasil Ltda., Rio de Janeiro, RJ, Brazil), or microwave irradiation (Model Sensor Crisp 38, Brastemp, Double Emission System, Manaus, AM, Brazil) with or without prior brushing of the denture. It is worth mentioning that, in addition to the 2% chlorhexidine solution, which is considered effective for disinfecting dentures, 19 - 22 , 25 , 26 cleaning protocols included the same solution in a concentration of 0.12% since this mouthrinse is generally available in hospitals, as was the case in the two participants in this trial. Participants were randomly assigned to one of the following study groups (with at least 20 individuals each):…”