Sabedra Vinicius, Poker Beatriz C, Oliveira Viviane C, Macedo Ana P, Zeuner Frank, Sakly Amina, Watanabe Evandro, Silva-Lovato Cláudia H
Master's student, Department of Dental Materials and Prosthesis, Ribeirão Preto School of Dentistry University of São Paulo (USP), Ribeirão Preto, São Paulo, Brazil.
Doctoral student, Department of Dental Materials and Prosthesis, Ribeirão Preto School of Dentistry, University of São Paulo (USP), Ribeirão Preto, São Paulo, Brazil.
J Prosthet Dent. 2025 Sep 1. doi: 10.1016/j.prosdent.2025.08.003.
Despite the importance of denture hygiene, little is known about how different hygiene protocols perform against multispecies biofilms, including Candida albicans, Staphylococcus aureus, and Streptococcus mutans, on denture surfaces made from conventional versus 3-dimensionally (3D) printed acrylic resins.
The purpose of this in vitro study was to evaluate the effect of hygiene protocols on a multispecies biofilm (C albicans, S aureus, and S mutans) formed on resin used for denture bases and teeth.
Circular specimens (Ø6×2 mm) were made from 3D printed denture resin (n=77) and heat-polymerized resin (n=77). Specimens with multispecies biofilm were randomly assigned to 3 hygiene protocols combining manual brushing with a soft brush and neutral soap (20 seconds per surface) plus immersion in 3 mL distilled water (control, for 20 minutes), Corega Tabs solution (BCt, for 15 minutes), or Nitradine solution (BNt, for 3 minutes). After rinsing in phosphate-buffered saline, the specimens were transferred to Letheen broth, 0.025 mL of the suspension was seeded on selective media, and the plates were incubated for 48 hours at 37 °C. Microbial load was quantified by CFU/mL count, and data were analyzed by the generalized linear model with the Wald test (α=.05). Biofilm viability was assessed by epifluorescence microscopy.
The BNt protocol eliminated S mutans and C albicans (CFU=0). For S aureus, BNt resulted in no detectable growth on either resin (P<.001). BCt reduced microbial load compared with the control for all species (P<.001) but was less effective than BNt. The 3D printed resin showed lower microbial load than the heat-polymerized resin for both base and tooth materials (P<.001). With BCt, the S aureus load was significantly higher on the heat-polymerized resin than on the 3D printed resin (P<.001). Microscopy images confirmed substantial biofilm reductions after both chemical protocols.
Brushing followed by immersion in Nitradine was the most effective hygiene protocol for controlling multispecies biofilm. The 3D printed denture resin demonstrated better resistance to microbial colonization than conventional heat-polymerized resin.
尽管义齿卫生很重要，但对于不同的卫生方案在由传统与三维（3D）打印丙烯酸树脂制成的义齿表面上对抗包括白色念珠菌、金黄色葡萄球菌和变形链球菌在内的多物种生物膜的效果知之甚少。
本体外研究的目的是评估卫生方案对在义齿基托和牙齿所用树脂上形成的多物种生物膜（白色念珠菌、金黄色葡萄球菌和变形链球菌）的影响。
圆形标本（直径6×2毫米）由3D打印义齿树脂（n = 77）和热聚合树脂（n = 77）制成。带有多物种生物膜的标本被随机分配到3种卫生方案中，这些方案将用软刷和中性肥皂手动刷牙（每个表面20秒）与浸泡在3毫升蒸馏水中（对照组，20分钟）、Corega Tabs溶液（BCt组，15分钟）或Nitradine溶液（BNt组，3分钟）相结合。在磷酸盐缓冲盐水中冲洗后，将标本转移到Letheen肉汤中，取0.025毫升悬浮液接种在选择性培养基上，并将培养皿在37°C下孵育48小时。通过每毫升菌落形成单位（CFU/mL）计数来量化微生物载量，并通过带有Wald检验的广义线性模型（α = 0.05）分析数据。通过落射荧光显微镜评估生物膜活力。
BNt方案消除了变形链球菌和白色念珠菌（CFU = 0）。对于金黄色葡萄球菌，BNt导致两种树脂上均未检测到生长（P <.001）。与对照组相比，BCt降低了所有物种的微生物载量（P <.001），但效果不如BNt。对于基托和牙齿材料，3D打印树脂的微生物载量均低于热聚合树脂（P <.001）。使用BCt时，热聚合树脂上的金黄色葡萄球菌载量显著高于3D打印树脂（P <.001）。显微镜图像证实两种化学方案后生物膜均有显著减少。
刷牙后浸泡在Nitradine中是控制多物种生物膜最有效的卫生方案。3D打印义齿树脂比传统热聚合树脂对微生物定植具有更好的抵抗力。
