Titratable Acidity and pH of Commercial Mouthwashes: A Comprehensive Analysis

The aim of this study was to measure and analyze the pH and titratable acidity (TA) of a wide range of commercial mouthwashes, available in the Republic of North Macedonia, to assess their potential erosive effect.Material and methods: A comprehensive market analysis was performed in the Republic of North Macedonia, including traditional markets (pharmacies, cosmetic chains, and consumer goods markets) as well as the online market. One to three packs of each mouthwash were purchased directly from vendors according to the inclusion and exclusion criteria, without requesting free samples from manufacturers or importers. A total of 81 mouthwashes were analyzed. pH and TA measurements were performed twice for each mouthwash, with results presented as Mean±SD.Results: The mean pH of the mouthwashes was 5.28±0.98 (range: 3.24 -7.74). More than half (n=48, 59.3%) had pH values below the critical threshold of 5.5. Only four (4.9%) had an initial pH ≥7. To neutralize acidic mouthwashes, an average of 5.75±10.29ml of 0.1M NaOH was required (range: 0.01–81.20ml). TA ranged from 0.01 to 162.4mmol/l, with a mean of 11.50±20.58mmol/l.Conclusion: A significant proportion of the mouthwashes (59.3%) had pH values below the critical threshold of 5.5. The titratable acidity values varied widely, with some mouthwashes exhibiting extremely high TA levels. Further research is needed to establish clear guidelines for safe use of mouthwashes with respect to their pH and titratable acidity values, especially to show the association between pH and TA of mouthwashes and the buffer capacity of saliva.