The relationship between morphological changes of the condyle and condylar position in the glenoid fossa.
OBJECTIVE
To investigate whether condylar morphological changes influence the condyle position in the glenoid fossa as well as the amount of condylar movement from the intercuspal position (IP) to the reference position (RP).


METHODS
Helical computed tomography was used for precise measurement of the joint spaces at IP and RP in 22 subjects (mean age 22.7 years). Subjects were divided into 2 groups, those without condylar bone changes (n = 11) and those with condylar bone changes (n = 11). The latter group was further subdivided into a flattening subgroup and an osteophyte subgroup, according to the type of condylar bone change.


RESULTS
There were no significant differences in the width of the anterosuperior or posterosuperior joint spaces at IP between either the 2 groups or the 2 subgroups. On the other hand, during condylar movement from IP to RP, the condyles moved significantly more superiorly and posterosuperiorly in the bone-change group than in the no-bone-change group. There was also greater absolute horizontal condylar movement between IP and RP in the bone-change group. In addition, within the bone-change group, the type of condylar bone change influenced the amount of condylar movement. Joints with osteophyte formation showed the most superior, posterosuperior, and absolute horizontal movement from IP to RP.


CONCLUSIONS
The findings that condyles of the bone-change group, especially those with osteophyte formation, were located significantly more anteroinferiorly in the glenoid fossa at IP than RP than the condyles of the no-bone-change group suggest that condylar IP-RP positional changes might be related to condylar shape alteration.
Tsuruta
Akemi
A
Division of Orthodontics, Department of Oral Biological Science, Course for Oral Life Science, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan.
Yamada
Kazuhiro
K
Hanada
Kooji
K
Hosogai
Akiko
A
Kohno
Shoji
S
Koyama
Jun-ichi
J
Hayashi
Takafumi
T
D000328:Adult; D000704:Analysis of Variance; D016723:Bone Remodeling; D003768:Dental Occlusion, Centric; D005260:Female; D006801:Humans; D007574:Jaw Relation Record; D008297:Male; D008335:Mandibular Condyle / Q000473:pathology* / Q000503:physiopathology; D009068:Movement; D018709:Statistics, Nonparametric; D013704:Temporomandibular Joint / Q000473:pathology*; D036542:Tomography, Spiral Computed