Weak evidence to support benefit of periodontal maintenance therapy in prevention of tooth loss.

DATA SOURCES: Medline, Embase, Cochrane Central Register of Controlled Trials (CENTRAL), OpenSIGLE (System for Information on Grey Literature in Europe) and reference lists of identified studies. Study Selection Cohort studies, case-control studies and case series limited to patients with periodontitis who underwent active periodontal treatment (APT) and followed a maintenance care programme for at least 5 years that reported data on tooth loss were included.

DATA EXTRACTION AND SYNTHESIS: Two independent reviewers screened the studies and extracted the data, with disagreements being resolved by discussion and consensus. Methodological quality was assessed using the Newcastle-Ottawa scale. Data were pooled into evidence tables and grouped according to the type of study. A descriptive summary was performed.

RESULTS: Thirteen retrospective case series were included in this review. The risk of bias assessment showed that eight studies were of medium methodological quality and five of low quality. Of 41404 teeth present after active periodontal treatment, 3919 were lost during PM. The percentages of tooth loss due to periodontal reasons and of patients who did not experience tooth loss varied from 1.5 to 9.8% and 36.0 to 88.5%. Studies' individual outcomes showed that different patient-related factors (ie, age and smoking), and tooth-related factors (tooth type and location and the initial tooth prognosis) were associated with tooth loss during PM.

CONCLUSIONS: The considerable heterogeneity found among studies did not allow definitive conclusions. Age, smoking and initial tooth prognosis were found to be associated with tooth loss during PM. Overall, patients must be instructed to follow periodic PM and quit smoking (smokers). Prospective cohort studies are required to confirm the possible predictors of tooth loss due to periodontal reasons. The allocation of patients into subgroups according to the type of periodontitis and smoking frequency will allow more accurate evaluations.