Oral lichenoid mucositis (OLM) of the oral mucosa is a histological diagnosis mainly characterised by a band of inflammatory infiltrate in lamina propria and basal cell degeneration. These features describe oral lichen planus or oral lichenoid reaction. However, it could be seen in oral dysplasia. The study aimed to assess the demographics and clinicohistological characteristics of patients with OLM and their relevance to dysplastic changes in the oral mucosa. This was a cross-sectional and retrospective study of archived and electronic records of individuals with histological confirmation of OLM at King Saud University Medical City, Saudi Arabia. The descriptive and correlation assessments were used to describe the demographics and clinicohistological characteristics and their associations, respectively [p < 0.05]. The analysis included 140 records of patients with histological confirmation of OLM with a mean age of 47 (±13), and 57% (n = 81) were females. Notably, 40% of patients had at least one medical condition, mainly diabetes mellitus, 74% were asymptomatic, and 52% had lesions in the buccal mucosa. Dysplasia was seen in 18 (12%) of the 140 reviewed records. Regarding the associations between study variables, dysplastic changes were associated with the male gender [p = 0.024] and were of no significance with increased age [p = 0.594]. Moreover, having oral symptoms was associated with older age [p < 0.001], medical history of diabetes [p = 0.0132] and hypertension [p < 0.001]. The present study findings could help indicate the individuals with histologically confirmed OLM who suffer the most from the clinical disease and have an increased risk of dysplastic changes. Therefore, symptomatic management and long-term follow-up can be planned accordingly.