The effect of myotonic dystrophy type 1 on temporomandibular joint and dentofacial morphology: A CBCT analysis

• Published in: Journal of oral rehabilitation 2023-10, Vol.50 (10), p.958-964
• Main Authors: Evlice, Burcu, Duyan Yuksel, Hazal, Evlice, Ahmet, Koc, Filiz
• Format: Article
• Language: English
• Subjects: Computed tomography; cone beam computed tomography; Dental occlusion; dentofacial morphology; mandibular condyle; Morphology; Muscles; Myotonic dystrophy; myotonic dystrophy type 1; Orthodontics; osseous changes; Palate; Patients; Sclerosis; Statistical analysis; Temporomandibular joint; Tin
• ISSN: 0305-182X; 1365-2842
• DOI: 10.1111/joor.13533

Background Myotonic dystrophy type 1 (DM1) is a neuromuscular multisystem disease. Early involvement of facial muscles may produce an extra load on the temporomandibular joint (TMJ) in DM1. Objectives This study aimed to investigate the morphological analyses of the bone components of temporomandibular joint (TMJ), and dentofacial morphology in myotonic dystrophy type 1 (DM1) patients by cone‐beam computed tomography (CBCT). Methods Sixty‐six individuals (33 DM1, and 33 healthy subjects) age ranging from 20 to 69 were included in the study. Clinical examinations of the patients' TMJ regions and evaluation of dentofacial morphology (maxillary deficiency, open‐bite, deep palate and cross‐bite) were performed. Dental occlusion was determined based on Angle's classification. CBCT images were evaluated regarding mandibular condyle morphology (convex, angled, flat and round) and osseous changes observed in the condyle (normal, osteophyte, erosion, flattening, sclerosis). DM1‐specific morphological and bony TMJ alterations were determined. Results DM1 patients showed a high prevalence of morphological and osseous TMJ changes, and statistically significant skeletal alterations. The analysis of CBCT scans indicated the prevalent condylar shape among patients with DM1 was flat, the main osseous abnormality was flattening, there was a tendency towards skeletal Class II and a posterior cross‐bite was frequently detected in DM1 patients. There was no statistically significant difference between the genders on the parameters evaluated in both groups. Conclusion Adult patients with DM1 presented a high frequency of crossbite, tendency to skeletal Class II and morphological osseous alterations of TMJ. The analysis of the morphological condylar alterations in patients with DM1 may be beneficial in the diagnosis of TMJ disorders. This study reveals DM1‐specific morphological and osseous TMJ alterations to provide an appropriate orthodontic/orthognathic treatment planning to patients. Adult patients with DM1 presented a high frequency of crossbite, tendency to skeletal Class II and morphological osseous alterations of TMJ. The progressive course of DM1 could affect prognosis of the dentomaxillofacial treatments. This CBCT study reveals DM1‐specific morphological and osseous TMJ alterations.