Root canal filling materials spread pattern mimicking root fractures in dental CBCT images.
OBJECTIVE
To clarify the cause of artificial tooth-root fracture lines in cone beam computed tomography (CBCT) images caused by root canal filling materials and to enhance the diagnostic performance of CBCT.


METHODS
We analyzed the CBCT images of 18 extracted human teeth (9 upper central incisors and 9 lower premolars) that were filled with a size 50 gutta-percha cone and inserted into tooth sockets in a human skull.


RESULTS
The CBCT images of the incisors displayed artificial lines in the oblique directions, notably the mesiobuccal, distolingual, distobuccal and mesiolingual directions, but only rarely in the cross-directions (buccal, lingual, mesial, and distal). In the premolars, the reverse was true, with lines mainly in the cross-directions, mesial and distal directions particularly. The lines were predominantly at the cervical slice.


CONCLUSIONS
Artifacts resulting from root filling material appear along the long axis of the alveolar bones, and resemble root fractures.
Associate Professor, Department of Oral Diagnosis, Tohoku University Graduate School of Dentistry, Sendai, Japan. Electronic address: Machapy@dent.tohoku.ac.jp.
Masahiro
M
Iikubo
Assistant Professor, Department of Oral and Maxillofacial Radiology and Diagnosis, Tsurumi University School of Dental Medicine, Yokohama, Japan.
Takashi
T
Osano
Professor, Division of Radiology, Department of Oral Diagnostic Sciences, Showa University School of Dentistry, Tokyo, Japan.
Tsukasa
T
Sano
Professor, Department of Oral Radiology, Asahi University School of Dentistry, Mizuho, Japan.
Akitoshi
A
Katsumata
Professor, Department of Oral and Maxillofacial Radiology, Aichi-Gakuin University School of Dentistry, Nagoya, Japan.
Eiichiro
E
Ariji
Professor, Department of Oral and Maxillofacial Radiology and Diagnosis, Tsurumi University School of Dental Medicine, Yokohama, Japan.
Kaoru
K
Kobayashi
Professor, Department of Oral Diagnosis, Tohoku University Graduate School of Dentistry, Sendai, Japan.
Takashi
T
Sasano
Associate Professor, Department of Oral and Maxillofacial Radiology, Tokyo Dental College, Tokyo, Japan.
Mamoru
M
Wakoh
Associate Professor, Division of Radiology, Department of Oral Diagnostic Sciences, Showa University School of Dentistry, Tokyo, Japan.
Kenji
K
Seki
Assistant Professor, Department of Oral Diagnosis, Tohoku University Graduate School of Dentistry, Sendai, Japan.
Ikuho
I
Kojima
Associate Professor, Department of Oral Diagnosis, Tohoku University Graduate School of Dentistry, Sendai, Japan.
Maya
M
Sakamoto
D016477:Artifacts; D001641:Bicuspid / Q000000981:diagnostic imaging; D054893:Cone-Beam Computed Tomography / Q000379:methods*; D006171:Gutta-Percha / Q000737:chemistry*; D006801:Humans; D066298:In Vitro Techniques; D007180:Incisor / Q000000981:diagnostic imaging; D012387:Root Canal Filling Materials / Q000737:chemistry*; D014082:Tooth Fractures / Q000000981:diagnostic imaging; D014092:Tooth Root / Q000000981:diagnostic imaging*
D012387:Root Canal Filling Materials; D006171:Gutta-Percha