Three-dimensional analysis of pulp chambers in maxillary second deciduous molars.
OBJECTIVE
The purpose of this study was to clarify the positional relationship between the crown contour and the pulp chamber using micro-CT system for restorations of maxillary second deciduous molar.


METHODS
Five maxillary second deciduous molar teeth each from the deciduous dentition and the mixed dentition periods were used. The positional relationship between the crown contour and pulp chamber was three-dimensionally observed by micro-CT. In addition, the thickness of the dentin at each of the pulp horns and the volume ratio of the pulp chamber against the whole crown were measured.


RESULTS
In relationship to the crown contour and the pulp chamber, the pulp horn of the mesiobuccal cusp showed greatest protrusion and eminent swelling of its mesial wall in both the deciduous dentition and the mixed dentition periods. Furthermore, the pulp chamber was shifted to the mesial side. The volume ratio of the pulp chamber to the whole crown, the ratio in the mixed dentition period showed to be significantly smaller than in the deciduous dentition period. The dentin thickness at the mesiobuccal pulp horn was the thinest.


CONCLUSIONS
These results suggest that in preparation of cavities in maxillary second deciduous molars, care is necessary not to expose of the mesiobuccal pulp horn. Especially, the mesial wall of the mesiobuccal pulp horn should be noted.
Amano
M
M
Department of Anatomy, Tokyo Dental College, 1-2-2 Masago Mihama-ku Chiba, 261-8502 Japan.
Agematsu
H
H
Abe
S
S
Usami
A
A
Matsunaga
S
S
Suto
K
K
Ide
Y
Y
D002648:Child; D003743:Dental Enamel / Q000033:anatomy & histology / Q000000981:diagnostic imaging; D003786:Dental Pulp Cavity / Q000033:anatomy & histology / Q000000981:diagnostic imaging*; D003804:Dentin / Q000033:anatomy & histology / Q000000981:diagnostic imaging; D003818:Dentition, Mixed; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008437:Maxilla; D008963:Molar / Q000033:anatomy & histology / Q000000981:diagnostic imaging*; D014057:Tomography, X-Ray Computed / Q000379:methods*; D019228:Tooth Crown / Q000033:anatomy & histology / Q000000981:diagnostic imaging; D014094:Tooth, Deciduous / Q000033:anatomy & histology / Q000000981:diagnostic imaging*