Dental wear represents an irreversible loss of dental hard tissue under the action of physical, chemical and mechanical factors, excluding dental caries and acute trauma. Four clinical forms of dental wear are described: erosion, attrition, abfraction, and abrasion. Most experts agree that in each clinical form multiple etiological factors are involved, one being predominant. Optical coherence tomography (OCT) is a non-invasive optical method characterized by a micronic resolution. The applications of this type of investigation are multiple in the medical field in recent years, and OCT is gaining a growing importance in dentistry. The study pointed out through OCT imaging for the erosive tooth wear lesion the existence of chemical aggression, with strong demineralization of enamel and dentin. For attrition lesion, OCT images showed the contribution of excessive force and friction movements specific to bruxism. In abfraction, OCT image revealed the importance of the mechanic factor in producing this form of tooth wear and abrasion damage studied may be considered physiological, according to patient age. OCT examination may reveal existing lesions in hard dental tissues for each clinical form and could bring evidence on the mechanisms involved.