The microbial changes in subgingival plaques of orthodontic patients: a systematic review and meta-analysis of clinical trials

Abstract

BackgroundOrthodontic treatment was found to have an impact on the quantity and constitution of subgingival microbiota. However, contradictory findings regarding the effects of fixed appliances on microbial changes were reported. The aim of this systematic review was to investigate the microbial changes in subgingival plaques of orthodontic patients.MethodsThe PubMed, Cochrane Library, and EMBASE databases were searched up to November 20, 2016. Longitudinal studies observing microbial changes in subgingival plaques at different time points of orthodontic treatment are included. The methodological quality of the included studies was assessed by Methodological index for non-randomized studies (MINORS). The studies that reported the frequency of subgingival periodontopathogens were used for quantitative analysis. Other studies were analysed qualitatively to describe the microbial changes during orthodontic treatment.ResultsThirteen studies were selected, including two controlled clinical trials, three cohort studies and eight self-controlled studies. Four periodontopathogens, including Aggregatibacter actinomycetemcomitans (Aa), Porphyromonas gingivalis (Pg), Prevotella intermedia (Pi) and Tannerella forsythia (Tf), were analysed. Following orthodontic appliance placement, the frequencies of Pg and Aa showed no significant change (P = 0.97 and P = 0.77), whereas the frequency of Tf significantly increased (P < 0.01) during short-term observation (0–3 months). The frequency of Pi showed a tooth-specific difference, as it presented no significant difference (P = 0.25) at the site of the first molar but was significantly increased (P = 0.01) at the incisor. During long-term observation (> = 6 months), two studies reported that the levels of subgingival periodontopathogens exhibited a transient increase but decreased to the pretreatment levels afterwards. After removal of the orthodontic appliance, the four periodontopathogens showed no significant difference compared with before removal.ConclusionThe levels of subgingival pathogens presented temporary increases after orthodontic appliance placement, and appeared to return to pretreatment levels several months later. This indicates that orthodontic treatment might not permanently induce periodontal disease by affecting the level of subgingival periodontal pathogen levels. Further studies of high methodological quality are required to provide more reliable evidence regarding this issue.

Profiling of subgingival plaque biofilm microbiota in female adult patients with clear aligners: a three-month prospective study

“…Many research studies have been carried out on microbial changes during fixed appliance treatment ( Freitas et al, 2014 ; Ireland et al, 2014 ). Our previous research found that the level of subgingival periodontal pathogens could temporarily increase after the placement of a fixed appliance ( Guo et al, 2017 ). However, we know little about how clear aligner treatment impacts microbiota and periodontal health.…”

Effect of orthodontic treatment on the subgingival microbiota: A systematic review and meta‐analysis

“…Orthodontic treatment has been associated with certain adverse effects to the periodontium, which are generally thought to be transient and not related to any lasting tissue damage . These include increased clinical plaque/bleeding indices, enlargement of gingival pockets, marginal bone loss and quantitative or qualitative changes in the oral microbiota . Orthodontic treatment‐induced microbial changes can be attributed to the plaque‐retentive characteristics of orthodontic appliances, while deepening of the gingival crevice through hyperplasia might offer a favourable environment for periodonto‐pathogenic anaerobic bacteria …”

“…The only existing systematic review of treatment‐induced subgingival changes assessed a limited number of databases, while methodological issues, such as choice of a statistical model for data synthesis, lack of subgroup analyses for potentially modifying factors, and grading of clinical recommendations with the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach justified this study.…”

Comparison of the Periodontal Status of Patients Undergoing Labial and Lingual Orthodontic Therapy

“…Indirectly, it also addresses the health of supporting structures [10]. A recent systematic review analyzed 13 studies; it concluded that the levels of subgingival periodontal pathogens increased after orthodontic appliance placement and appeared to return to the pretreatment levels several months later [11]. Placement of orthodontic brackets influences the accumulation and composition of the supragingival and subgingival microbiota [12].…”