Candida species (spp) are commensal yeast that can only instigate oral infection (oral candidosis – OC) when there is an underlying predisposing condition in the host. We investigated four controversial topics on OC: (i) How can a microbiological determination of OC be made as Candida spp. are commensal yeasts and not all of them form hyphae or pseudohyphae during infection? (ii) Is median rhomboid glossitis (MRG) a manifestation of candidal infection? (iii) Can candidal infection cause palate papillary hyperplasia (PPH)? (iv) What is the best therapeutic treatment for denture‐associated erythematous stomatitis (DAES)? Results from extensive literature searches, including a systematic review, suggested the following: (i) the diagnosis of OC merely on the basis of the presence of yeasts is an oversimplification of a complex process. No convincing evidence of a single test or method better able to discriminate the transition from candidal saprophytism to pathogenicity has been reported in the literature; (ii–iii) conclusive evidence of a direct aetiopathogenic relationship between MRG and PPH and candidal infection has not been found; and (iv) only limited evidence is available for any DAES treatment, thus making it impossible to make strong therapeutic recommendations.