Impact of Different Bedtime Oral Cleaning Methods on Dental-Damaging Microbiota Levels

Abstract

Bedtime teeth cleaning is strongly recommended to limit overnight oral bacterial growth, but the impact of different cleaning methods on oral microbiota remains to be determined. Here we evaluated the efficiency of three oral cleaning methods in decreasing distinct subtypes of dental-damaging bacteria (DDB) using quantitative real-time PCR (qPCR) and 16s-based taxonomic profiling. Materials and Methods: This was a randomized, controlled study of 58 healthy subjects who performed three timed oral cleaning methods for two consecutive nights: tooth brushing with sodium fluoride-containing toothpaste followed by tongue cleaning (BT); cleaning of gums and teeth by rubbing with an index finger followed by tongue cleaning (GIFT); and GIFT with the addition of rice husk activated charcoal (CT). Saliva samples were collected the following morning for qPCR and metagenomics analysis. Results: All three oral cleaning methods resulted in a significant decrease (P < 0.006) in the quantity of DDB compared with no cleaning (NC) controls. Bonferroni post hoc analysis showed that GIFT and CT decreased Aggregatibacter actinomycetemcomitans and Streptococcus mutans levels compared to the BT method (P < 0.005). Metagenomics data also showed a more significant decrease in many pathogenic bacteria using the GIFT and CT methods compared to the BT method. Conclusion: BT and GIFT are effective oral cleaning methods and reduce DDB levels. The greater flexibility of a finger to reach all areas of the teeth, gums, and inner cheeks that are inaccessible to a toothbrush to disturb biofilms makes GIFT a better method than traditional toothbrushing for bedtime oral cleaning.