Is nutritional intervention an improvement factor in the management of periodontitis? A systematic review.

Aims: This systematic review aimed to evaluate the effect of nutritional intervention in the management of periodontitis.

Methods: This study was registered on the Prospective International Registry of Systematic Reviews-PROSPERO, under the registration number CRD42017076674. The database searching was performed on: Pubmed, Scopus, Web of Science, Clinical Trials and Lilacs. The OpenGrey and Google Scholar were also assessed for searching the grey literature. The PICO framework was carried out, in which the participants (P) were humans with periodontitis receiving conventional periodontal therapy simultaneously with dietary supplements (I), compared (C) with those managed with conventional therapy only, having as an outcome (O) the influence-or not influence-of nutritional intervention in the management of periodontitis. After the searching, duplicates were removed and articles were first assessed by title and abstract, following the inclusion and exclusion criteria; then, the full text of the remaining articles were reviewed. All steps within the review process were performed independently by two reviewers and checked by a third-party disagreement evaluator. For quality/risk of bias assessment of the study selection, The Cochrane Collaboration's tool for randomized studies and Robins-TOOL for non-randomized studies (ROBINS-I) were performed. The Grading of recommendations, assessment, development and evaluation (GRADE) was used for assessing the level of evidence.

Results: A total of 2574 citations were recorded, but only four were considered eligible. The included studies reported different nutritional interventions such as fruit concentrate, vegetables and fruit juice powders, multivitamins, fish oil, and a customized dietary advice. The three studies using nutritional supplements showed improvements in at least one clinical parameter of periodontitis -reduction of probing depths, attachment gain, crevicular fluid decreased, reduced bleeding values on probing-after 2-6 months. Although, only two articles presented a moderate risk of bias, a very low level of evidence was found among the four studies taken together.

Conclusions: Despite the results suggested that nutritional intervention is beneficial for periodontal therapy, the evidence in general, is inconsistent and imprecise. More interventional studies with longer periods of follow-up and the assessment of a specific nutritional intervention must be conducted.