Faculty of Dental Medicine, Universidade Católica Portuguesa, 3504-505 Viseu, Portugal.
Centre for Interdisciplinary Research in Health (CIIS), Universidade Católica Portuguesa, 3504-505 Viseu, Portugal.
Int J Mol Sci. 2024 Aug 6;25(16):8566. doi: 10.3390/ijms25168566.
Methicillin-resistant (MRSA) is considered one of the most harmful bacteria to human health. Dentistry, like all healthcare disciplines, places great emphasis on preventing scenarios that may result in cross-infection. Although various tested and already used materials are suitable for filling the root canal system, Gutta-Percha (GP) remains the preferred and widely accepted gold standard.
We performed an in vitro analysis of the contamination of GP points, regarding the strains of Methicillin-resistant (MRSA) and Methicillin-sensitive (MSSA) , using classical microbiology methods and molecular biology techniques.
Gutta-Percha points of two different brands from opened packages (already in use for 1 month) were collected for analysis. The assessment involved incubating the GP points in Brain Heart Infusion (BHI) medium to detect microbial growth. Growing microorganisms were plated on a selective and differential chromogenic medium for MRSA/MSSA strains, and the identification of isolates was confirmed by Polymerase Chain Reaction (PCR). In the case of microbial growth, the GP point was submitted to a disinfection protocol.
From the 315 collected GP points, only 6 (1.9%) resulted in being positive for microbial growth. After confirmation by PCR, only one sample of the six GP points was contaminated by MRSA, and the remaining five were MSSA-contaminated. The disinfection protocol was effective in all contaminated GP points.
The Gutta-Percha points from opened pre-sterilized packages showed a very low degree of contamination by MRSA/MSSA. However, the detection of MSSA and MRSA strains raises concerns about potential contamination in dental clinic environments, and this risk cannot be considered negligible.
使用经典微生物学方法和分子生物学技术,对已使用 1 个月的两种不同品牌的预消毒包装的牙胶尖进行污染检测,以分析耐甲氧西林金黄色葡萄球菌(MRSA)和甲氧西林敏感金黄色葡萄球菌(MSSA)菌株的污染情况。
收集用于分析的已使用 1 个月的两种不同品牌的预消毒包装的牙胶尖。评估包括将牙胶尖在脑心浸液(BHI)培养基中孵育,以检测微生物生长。将生长的微生物接种在选择性和差异显色培养基上,用于 MRSA/MSSA 菌株,通过聚合酶链反应(PCR)确认分离株的鉴定。如果出现微生物生长,则对牙胶尖进行消毒处理。
在收集的 315 个牙胶尖中,只有 6 个(1.9%)的牙胶尖出现微生物生长阳性。经 PCR 确认后,仅 6 个牙胶尖样本中有 1 个被 MRSA 污染,其余 5 个被 MSSA 污染。所有污染的牙胶尖均通过消毒方案得到有效处理。
从已打开的预消毒包装中取出的牙胶尖显示出极低程度的 MRSA/MSSA 污染。然而,MSSA 和 MRSA 菌株的检测引发了对牙科临床环境中潜在污染的关注,且不能认为这种风险可以忽略不计。