An observation on the cases of fracture and luxation of the temporomandibular joint by M-V cephalogram

Mento-Vertex (M-V), axial cephalometric projection for temporomandibular joint (TMJ) examination is not commonly utilized.We observed the condylar positions in the cases of fracture (N=43, bilateral 12 cases and unilateral 31 cases) and luxation (N=4, bilateral 3 cases and unilateral 1 case) of TMJ by this cephalogram at pre-and post-treatment.The results obtained were as follows: Anterio-medial displacement types of the condylar neck region amounted to 20 TMJ, (36. 4%), and the same types of dislocation fracture with luxation amounted to TMJ (18. 2%).In the cases, that received conservative treatment, the condylar positions did not show a great different between pre-and post-treatment. Deformed cure of the TMJ was observed in many cases.In the cases that received surgical treatment, about 73% TMJ with dislocation were reduced and fixed in the original anatomical position of the condyle.Relation between the dislocation type of the condylar fracture and prognosis was not found, but good prognosis was obtained in both cases of conservative and surgical treatment.We examined the condylar position difference between fracture with luxation and luxation only. As a result, the condylar position fracture with luxation was closer than one of luxation to the original anatomical position.