Assessment of microbial growth in various aligner materials

Microbial accumulation on clear aligners poses a risk for dental and periodontal health, particularly when proper hygiene practices are not maintained. Therefore, it is of interest to evaluate and compare microbial growth on three different aligner materials: Invisalign, Straumann Clear Correct and Novoalign. An in vivo observational study was conducted on 30 subjects, divided into three groups based on the type of aligner used. Microbial samples were collected at baseline (unused aligners, T0) and after 14 days of intraoral use (T1). Samples were cultured using Soybean Casein Digest Agar and Mannitol Salt Agar to quantify Streptococcus mutans, Staphylococcus aureus and Lactobacillus spp. All tested aligner materials exhibited microbial colonisation, with differences based on material composition and surface characteristics. Emphasis on hygiene practices is essential during aligner therapy.