ImportanceDry mouth, oral candidiasis, and recurrent aphthous ulcers are 3 of the most common oral conditions that may be associated with patient discomfort, decreased quality of life, and morbidity.ObservationsIn a meta-analysis of 26 population-based cohort and cross-sectional studies, the global prevalence of dry mouth symptoms was 23% (95% CI, 18% to 28%), placing individuals at risk of oral candidiasis, dental caries, dysgeusia, masticatory/speech impairment, and oropharyngeal dysphagia. Dry mouth is associated with using more than 3 oral medications per day (odds ratio [OR], 2.9 [95% CI, 1.4 to 6.2]), head and neck radiation, and Sjögren disease. Symptoms may include difficulty swallowing and speaking, thirst, and halitosis. Dry mouth is associated with an 11.5% (95% CI, 3.6% to 27%) higher risk of oral candidiasis, based on a meta-analysis of 6 observational cohorts. Management of dry mouth includes mechanical salivary stimulants, oral moisturizers, and/or systemic sialagogues. Oral candidiasis is an opportunistic fungal infection caused by overgrowth of the Candida genus with C albicans, which accounts for 76.8% of infections. The prevalence of oral candidiasis is higher in patients who are immunosuppressed, for example, those with HIV (35% [95% CI, 28% to 42%]) and those with salivary gland hypofunction (OR, 3.02 [95% CI, 1.73 to 5.28]). Common risk factors associated with oral candidiasis include use of antibiotics (P = .04) and oral mucosal disorders such as lichen planus. Oral burning and dysgeusia are common symptoms of oral candidiasis. Treatment includes addressing risk factors and use of topical and/or systemic antifungal medications. Recurrent aphthous stomatitis is characterized by symptomatic round or oval oral ulcers, which are covered by a gray-white fibrin layer and encircled by an erythematous ring. A meta-analysis of 10 case-controlled studies revealed an increased risk of recurrent aphthous stomatitis associated with polymorphism of IL-1β (+3954C/T) (OR, 1.52 [95% CI, 1.07 to 2.17]) and IL-1β (−511C/T) (OR, 1.35 [95% CI, 1.09 to 1.67]). Another meta-analysis of 9 case-control studies reported that patients with recurrent aphthous stomatitis had a higher frequency of nutritional deficiencies, including vitamin B12 (OR, 3.75 [95% CI, 2.38 to 5.94]), folic acid (OR, 7.55 [95% CI, 3.91 to 14.60]), and ferritin (OR, 2.62 [95% CI, 1.69 to 4.06]). Recurrent aphthous stomatitis can be associated with systemic diseases. A meta-analysis of 21 case-control studies revealed that celiac disease is associated with a higher incidence of recurrent aphthous stomatitis (25% vs 11%; OR, 3.79 [95% CI, 2.67 to 5.39]; P <.001). Topical corticosteroids are first-line agents to manage recurrent aphthous stomatitis; however, systemic medications may be necessary in more severe cases.Conclusions and RelevanceDry mouth, oral candidiasis, and recurrent aphthous ulcers are common oral conditions that may be associated with patient discomfort, decreased quality of life, and morbidity. First-line treatment includes over-the-counter sialagogues for dry mouth, topical antifungals for oral candidiasis, and topical corticosteroids for aphthous ulcers. Oral conditions that do not improve with first-line treatment may require treatment with systemic medications.