Method: Test group included 30 participants, who had disc displacement with reduction (according to RDC-TMD) in right, left or both joints. Control group included 12 individuals with no signs and symptoms of the TMD. Each participant gave written informed consent, which was approved by Ethical Committee of the School of Dentistry, University of Zagreb. CR record (chin point guidance, front jig) was made three times by every participant, in one session, and condylar position for each CR record was determined and recorded using the electronic ultrasound measuring device (Arcus Digma II, Kavo, Biberach, Germany. Data were transferred to the computer, processed and analyzed. Distances between CR records were measured (X-anteroposterior, Y-vertical, Z-transversal values). For every participant, mean value of distances between CR records was calculated, and used for statistical evaluation. Data were analyzed statistically using the T test.
Result: Mean values of the obtained distances and T test are summarized in the Table (X-anteroposterior; Y-vertical; Z-transversal; L-left; R-right; E-experimental group; C-control group).
XE |
XC |
SDE |
SDC |
P |
|
XL |
0,10 |
0,11 |
0,10 |
0,07 |
0,8625 |
YL |
0,16 |
0,21 |
0,10 |
0,11 |
0,1238 |
ZL |
0,08 |
0,11 |
0,07 |
0,06 |
0,3134 |
XR |
0,10 |
0,11 |
0,09 |
0,07 |
0,8123 |
YR |
0,17 |
0,14 |
0,10 |
0,09 |
0,3890 |
ZR |
0,08 |
0,11 |
0,07 |
0,06 |
0,3640 |
Conclusion: There is no difference in reproducibility of the CR record between patients with disc displacement with reduction and TMJ healthy individuals (p>0.05). When doing CR record on a patient with disc displacement with reduction, standard precautions are acceptable. Obtained results must be interpreted within the experimental group, and not projected on the other TMD groups.