Oral and maxillofacial radiologyUltrasound evaluation of masseter muscle changes in stabilization splint treatment of myofascial type painful temporomandibular diseases

ObjectivesTo detect whether stabilization splint (SS) treatment of painful myofascial type temporomandibular diseases (TMD) changes the masseter muscle morphology using ultrasound (US).Study designThirty-five patients with painful myofascial TMD receiving SS treatment were studied. Masseter thickness, length, internal echo-fibrillary structure and vascularization were evaluated using gray-scale and power Doppler US just before and 3 months after the SS application. Visual analog scale (VAS) and mouth opening measurements were used to measure the outcome of treatment.ResultsA significant shortening in the masseter muscle length (R: −3.67 mm, P: .010; L: −3.97 mm, P: .005) and thickness (R: −0.93 mm, P: .005; L: −0.90 mm, P: .016) was noted. No change in the internal echo-fibrillary structure or vascularization was detected. A significant decrease in VAS scores (Median: 5-0.5 P < .05) and mouth opening (42.77 ± 7.86 mm to 38.69 ± 6.21, P < .05) was also detected.ConclusionSSs modify and reduce the dimensions of masseter muscle.