Effect of xerostomia on the prevalence of tooth wear in orthodontic patients

Abstract

1. Purpose Tooth wear is a multifactorial condition influenced by mechanical, chemical, and biological factors, and the potential role of xerostomia in orthodontic patients remains unclear. This systematic review aimed to evaluate the available evidence regarding the effect of xerostomia and salivary alterations on the prevalence and severity of tooth wear in patients undergoing orthodontic treatment. 2. Methods This study was conducted as a systematic review. A structured electronic search was performed across four databases: PubMed, Google Scholar, Scopus, and ScienceDirect, using keywords and MeSH terms related to xerostomia, saliva, tooth wear, and orthodontic treatment. Predefined inclusion and exclusion criteria were applied, limiting studies to primary observational and clinical research published from 2000 onwards in English. Methodological quality was assessed using the Critical Appraisal Skills Programme (CASP) tools, risk of bias was evaluated using the ROBINS-I tool, and the overall certainty of evidence was graded using the GRADE framework. Findings were synthesised narratively. 3. Results The included studies were primarily observational and investigated either the effect of orthodontic treatment on tooth wear or the influence of salivary changes during orthodontic therapy. Some studies reported measurable enamel loss and increased anterior tooth wear, particularly with longer treatment duration. In contrast, other studies found no significant difference between orthodontically treated and untreated individuals. Additionally, several studies demonstrated that fixed orthodontic appliances can alter salivary parameters, including pH, flow rate, and microbial composition, potentially increasing susceptibility to enamel demineralisation and tooth wear. 4. Conclusion The evidence suggests a possible association between xerostomia, altered salivary function, and tooth wear in orthodontic patients; however, the overall strength of evidence is limited due to methodological heterogeneity and the predominance of observational study designs. Further well-designed longitudinal studies are required to clarify this relationship and support the development of effective preventive strategies in orthodontic practice.