Is pre-operative full mouth plaque score related to inflammatory complications in lower third molar surgery? Cohort study

Abstract Objectives The aim of this study was to investigate the association between pre-operative oral hygiene status and the occurrence of infectious-inflammatory complications, perceived pain, and swelling after lower third molar surgical extraction. Since oral hygiene is a modifiable factor, this study could provide suggestions to improve the success rate of third molar surgery. Materials and methods A cohort study was designed including two hundred twenty-two surgeries performed in adult patients. Full mouth plaque score (FMPS), as a parameter for oral hygiene status, demographic, anatomic and surgical variables were considered as predictor variables. Postoperative inflammatory complications, pain, swelling, and use of antibiotics were considered as study outcomes. The Common Factor Analysis was used to obtain a smaller set of new and not intercorrelated variables. A series of logistic regression analyses were used to assess the association between FMPS and the outcome variables. Results FMPS was found independently associated with post-operative inflammatory complications, significantly, if treated as continuous variable, and marginally if treated as binary variable (threshold ≤ 20%/>20%). The association between FMPS and postoperative pain depended on the surgical complexity and was marginal if the score was treated as continuous variable, and significant if treated as binary variable. FMPS was found independently associated with postoperative antibiotic use if treated as continuous variable and not associated if treated as binary variable. An independent association between FMPS and postoperative swelling was found if the score was treated as continuous variable, while the association depended on sex if the score was treated as binary variable. Conclusions FMPS has a predictive role in the occurrence of post-operative inflammatory complications and post-surgical related symptoms and signs after lower third molar surgery. Clinical relevance It seems appropriate to evaluate the pre-operative FMPS to estimate the risk of patient discomfort and inflammatory complications in the post-operative period. Assuming that FMPS is causally associated with complications, in patients with high FMPS, it would be advisable to reschedule the surgery and perform a further pre-operative oral hygiene session to improve overall treatment outcomes and reduce the need for antibiotic use.