Evaluation of Mandibular Movement Functions Using Instrumental Ultrasound System.
OBJECTIVE
The article deals with routinely performed instrumental temporomandibular joint (TMJ) examinations and interpretation of findings obtained from the Arcus Digma ultrasound device in individuals with or without clinical symptoms of temporomandibular disorders (TMD). The aim of this study was to analyze mandibular movement functions and the relationship between incisors and condylar movement parameters during jaw opening, which may be helpful for clinical evaluation in these patients.


METHODS
The study group consisted of 84 young students with no dental problems and other serious acute or chronic diseases in the medical history; the students were examined both clinically and with the Arcus Digma ultrasound device.


RESULTS
Helkimo Di = I was the most common score in 49 participants, and Helkimo Di = II in a significantly (p < 0.01, Di = I vs. Di = II) smaller number of participants. Medical history revealed symptoms of unilateral mastication in 15 participants and a statistically significant increased (p < 0.02, participants with symptoms of unilateral mastication vs. asymptomatic) condylar range of motion parameter during retrusion. Also a significant decrease (p < 0.03, participants with symptoms of unilateral mastication vs. asymptomatic) of the incisal and condylar ranges of motion during mouth opening was found. Limitation of mouth opening, defined as a decrease of inter-incisal distance, appeared in 19 participants (22.6%) and in 25 participants (29.8%) measured instrumentally with the Arcus Digma device. A comparison of instrumental result examinations of the right and left TMJs showed positive correlations of the range of mandible opening movement with the Posselt opening movement (r = 0.75) and opening/closing movements with the Posselt closing movements (r = 0.70). A correlation was demonstrated (r = 0.81) between the condylar range of motion studied on the left and on the right TMJ during mandible opening movement. Correlations were also found between opening-closing movements and the condylar range of motion of the left TMJ, and between the opening-closing movement and the condylar range of motion of the right TMJ during the opening movement.


CONCLUSIONS
According to the results of this study with instrumental Arcus Digma ultrasound device measurements of mandibular movements, data were provided on irregularities in TMJ function not detected in participants with or without clinical symptoms of TMD.
Department of Prosthodontics, University of Medical Sciences, Poznań, Poland.
Anna
A
Sójka
Department of Pathophysiology of Locomotor Organs, University of Medical Sciences, Poznań, Poland.
Juliusz
J
Huber
Department of Bioinformatics and Computational Biology, University of Medical Sciences, Poznań, Poland.
Elżbieta
E
Kaczmarek
Department of Prosthodontics, University of Medical Sciences, Poznań, Poland.
Wiesław
W
Hędzelek
D000328:Adult; D000886:Anthropometry; D005260:Female; D006801:Humans; D007574:Jaw Relation Record; D008297:Male; D011044:Poland; D016059:Range of Motion, Articular / Q000502:physiology*; D013704:Temporomandibular Joint / Q000000981:diagnostic imaging* / Q000502:physiology*; D013705:Temporomandibular Joint Disorders / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D014463:Ultrasonography / Q000379:methods*
Temporomandibular joint; clinical and instrumental measurements; healthy subjects; mandibular movement recordings