Alterations of mandibular movement patterns after total joint replacement: a case series of long-term outcomes in patients with total alloplastic temporomandibular joint reconstructions

Total Temporomandibular Joint Prosthetic Reconstruction: The Importance of Lateral Pterygoid Muscle Reattachment to Lateral Excursive and Protrusive Mandibular Movement

“…1 Diminished or unimproved lateral and protrusive jaw movement is a commonly accepted consequence of complete TMJ replacement. 2 Lateral excursive and protrusive function should, however, be considered and reported as an important measure of success after alloplastic TMJ replacement. To achieve such success, surgeons must comprehensively plan the reconstruction and reattach the lateral pterygoid muscle's inferior head (LPM-IH) to the prosthetic TMJ to support normal functional occlusion and mandibular motion.…”

“…3 Custom prosthetics support the creation of an optimal articulating surface and thereby improved condylar motion. 2 Finally, condylar movement is guided by contraction of the muscles of mastication in a complex combination of rotational and translational movements. 3 The masseter, temporalis, and pterygoid muscles work to guide MIO and protrusive and lateral excursive movements.…”

“…3 The masseter, temporalis, and pterygoid muscles work to guide MIO and protrusive and lateral excursive movements. 2 Of the 3 movements, historically, only MIO is reported as a primary measure of success following total TMJ replacement. 1…”

“…Still, for most patients, loss of function is accepted as 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 part of the procedure. 2 Inappropriate form and postprocedural scar tissue have also been implicated in the loss of protrusive and lateral movement after total TMJ replacement. 2 However, the advent of custom prosthetics and the use of fat grafting both support improved condylar motion.…”

“…2 Inappropriate form and postprocedural scar tissue have also been implicated in the loss of protrusive and lateral movement after total TMJ replacement. 2 However, the advent of custom prosthetics and the use of fat grafting both support improved condylar motion. 2 Because the LPM orchestrates a variety of complex jaw movements, restoring its function has the potential to support functional occlusion, decrease pain, and improve patient quality of life; all outcomes that I have observed in practice.…”