Correlation between craniocervical posture and upper airway dimension in patients with bilateral anterior disc displacement

OBJECTIVE

To investigate the relationship between upper airway dimension and craniocervical posture in adult patients with bilateral anterior disc displacement and to provide some references for clinical diagnosis and plan formulation in orthodontics.

METHODS

Based on RDC/TMD (Research Diagnostic Criteria for Temporomandibular Disorder), 98 Patients were divided into three groups by two experienced TMJ (Temporomandibular Joint) specialists: bilateral disc normal position group (BN), bilateral anterior disc displacement with reduction group (ADDWR) and bilateral anterior disc displacement without reduction group (ADDWoR). Inter-group comparison and correlation analysis were performed after 11 craniocervical posture and 15 upper airway dimension measurements finished with Dolphin and Uceph software in Two or Three-dimensional.

RESULTS

Anterior disc displacement often accompanied with extension of craniocervical posture, as ADDWR and ADDWoR groups have significantly higher cervical curvature and inclination than BN group (P < 0.05). Simultaneously anterior disc displacement often associated with constrained upper airway dimension for the total and each segment upper airway volume were significantly smaller in ADDWR and ADDWoR than BN group (P < 0.05). Correlation analysis revealed that C0-C1 (the distance from the base of the occipital bone (C0) to the posterior arch of the atlas (C1)) is significantly related to the total and each segment upper airway volume reduction (P < 0.05).

CONCLUSION

There exists markedly close correlation between anterior disc displacement and craniocervical posture forward extension, which may be physiologically adaptive cervical extension to keep oropharyngeal airway unobstructed as upper airway dimension constrained by anterior disc displacement.

CLINICAL RELEVANCE

These findings allow us to infer the potential consequences if the treatment of anterior disc displacement would result in an improvement of intervertebral relationships and upper airway constraint.

Correlation between temporomandibular joints and craniocervical posture in patients with bilateral anterial disc displacement

OBJECTIVE

To study the changes of temporomandibular joints and craniocervical posture in adult patients with bilateral anterior disc displacement, and to explore their correlation, which may provide some clinical value for clinical diagnosis and treatment planning.

METHODS

Ninety-eight adult patients were divided into 3 groups: 29 patients in bilateral disc normal position group (BN), 33 patients in bilateral Anterior Disc Displacement With Reduction group (ADDWR) and 36 patients in bilateral Anterior Disc Displacement Without Reduction group (ADDWoR). Dolphin and Uceph software were used to measure 14 items of temporomandibular joint and 11 items of craniocervical posture for comparison and correlation analysis between groups.

RESULTS

There were significant differences in bilateral joint space between three groups. Compared with the BN, the anteroposterior diameter of the condyle was significantly reduced, the condyle was significantly displaced posteriorly and superiorly in the ADDWR and ADDWoR, but the joint fossa width and joint fossa depth did not change significantly. Cervical curvature and inclination were greater in patients with anterior disc displacement than BN, indicating that the craniocervical posture of adult patients with anterior disc displacement was extended and protrusive.

CONCLUSION

Anterior disc displacement of the temporomandibular joint can displace the condyle upwards and posteriorly and reduce the anteroposterior diameter of condyle, and then make the condyle closer to the wall of articular fossa to induce joint symptoms. Additionally, craniocervical postural position is significantly affected, which may be related to compensate for the effects of airway space.