Analysis of the growth of dental plaque on the surface of orthodontic vacuum-formed retainers following the use of different cleaning methods

Background This study aimed to identify the most effective cleaning method for removable orthodontic clear vacuum-formed retainers (VFRs) and to assess the amount of dental plaque growth by microbiological analysis after performing mechanical, chemical and a combination of both cleaning methods.

Methods The subjects were 23 patients from the Princess Nourah bint Abdulrahman University Dental Clinic who were in the retention phase of their orthodontic treatment using VFRs. The duration of the study was five weeks. Every week the subjects were given a new VFR and asked to wear it (20–22 hr/day) with instructions to use one of the following specific cleaning methods: running water, brushing with soap, immersing in sodium carbonate with sulphate cleaning solution, brushing with a fluoride toothpaste, and brushing with water. At the end of each week, the VFRs were returned, and a microbiological analysis was performed.

Results At a statistically significant level, the highest bacterial concentrations were found on VFRs cleaned with running water compared to the other cleansing methods. There was no significant difference found in the bacterial count between brushing and toothpaste; brushing and soap, brushing and water, and tablet cleaning methods. Brushing with a fluoride toothpaste was the most effective method for cleaning the VFRs.

Conclusion The findings of the present study indicate that cleaning VFRs with water alone is insufficient. Using chemical cleaning solutions and/or mechanical brushing significantly reduces the bacterial count on VFRs surfaces. Brushing with a fluoride toothpaste seems to be the most effective cleaning method for VFRs, given the limitations of the study.