Objective: Dental caries is one of the most common chronic diseases affecting millions of people globally. Some studies revealed the presence of bidirectional relationship between allergic rhinitis (AR) and oral diseases, with each disease having a potential impact on the other. In this study we aimed to systematically review the literature and analyze the available evidence regarding whether AR contributes to the development of dental caries.
Methods: Three authors, members of the YO-IFOS rhinology study group, independently analyzed the data sources (Pubmed, the Cochrane Library, EMBASE, SciELO) for papers assessing the relationship between rhinitis and caries, in adult and pediatric patients.
Results: Eight studies met the inclusion criteria (87612 participants). Six studies were performed in children. A total of three studies found an association between AR and dental caries. Only two studies had adjusted the measure of effect for potentially confounding variables. Regarding the quality of the selected studies according to the NICE classification, the most observed methodological limitations detected were: (1) the cross-sectional design of the included studies which could have introduced a simultaneity bias, and (2) not clearly reporting the inclusion and exclusion criteria.
Conclusion: This systematic review can neither confirm nor deny the presence of an association between AR and caries. Despite the evidence is very scarce to conclude a relationship between AR and caries, the option for examining patients with repetitive caries by an otolaryngologist and those with AR by odontologist should be considered, as these examinations do not possess any risk for the patient.
Keywords: Allergic rhinitis; allergy; caries; oral disease; periodontitis.