Structured Differential Diagnosis of Orofacial Pain Associated with an Enamel Crack Using ICOP and ICHD-3: A Case...

Background: Cracked teeth may present with variable and atypical symptoms, sometimes mimicking non-odontogenic orofacial pain conditions, making diagnosis challenging, particularly when cracks appear limited to enamel. Case presentation: A 36-year-old woman presented with intermittent pain in a mandibular molar radiating to the ipsilateral temporal region. Clinical examination identified a crack line on the lingual surface of the mandibular first molar. Pulp sensibility testing (cold test and electric pulp test), occlusal loading tests, and cone-beam computed tomography (CBCT) were performed. CBCT was used primarily to exclude vertical root fracture and periapical pathology, and no radiographic abnormalities were identified. Differential diagnosis was conducted using structured diagnostic frameworks, including the International Classification of Orofacial Pain and the International Classification of Headache Disorders (3rd edition). Diagnostic local anaesthesia eliminated both biting pain and referred pain, supporting an odontogenic source. Collectively, the findings suggested that the enamel crack was the most likely source of odontogenic pain, although a definitive causal relationship could not be established. Because pulp sensibility remained normal, conservative management was selected. Crack sealing with a methyl methacrylate-based adhesive resin resulted in complete symptom resolution that was maintained throughout a 3-year follow-up period without the need for root canal treatment. Conclusions: Although the diagnosis remained probabilistic, the structured diagnostic approach, together with the favourable clinical response after crack sealing, supported the enamel crack as the most likely source of odontogenic pain.