Journal List > J Korean Assoc Oral Maxillofac Surg > v.37(6) > 1032505

J Korean Assoc Oral Maxillofac Surg. 2011 Dec;37(6):477-482. Korean.
Published online December 27, 2011.
Copyright © 2011 by The Korean Association of Oral and Maxillofacial Surgeons
Study on bone healing process following cyst enucleation using fractal analysis
Hun-Jun Lim,1 Seung-Soo Lee,1 Won-Ki Kim,1 Byung-Hun Ohn,1 Sang-Moon Choi,1 Se-Ri Oh,1 Seung-Ki Min,1,2 and Jun Lee1,2
1Department of Oral and Maxillofacial Surgery, School of Dentistry, Wonkwang University, Daejeon, Korea.
2Bone Regeneration Research Institute, Wonkwang University, Daejeon, Korea.

Corresponding author: Jun Lee. Department of Oral and Maxillofacial Surgery, Daejeon Dental Hospital, Wonkwang University, 1268, Doonsan 2-dong, Seo-gu, Daejeon 302-120, Korea. TEL: +82-42-366-1146, FAX: +82-42-366-1115, Email:
Received July 16, 2011; Revised September 05, 2011; Accepted October 12, 2011.



Bone regeneration of cystic defects of the jaws after a cyst treatment requires lengthy healing periods. Generally, the bony changes are observed periodically through a visual radiographic reading as well as by the clinical opinion and radiographic images (panorama, periapical view), but it is difficult to compare the objective bony changes using only the radiographic density. In addition, it is difficult to observe minute bony changes through a visual radiographic reading, which can lead to a subjective judgment. This study exmined the bone density after the enucleation of a jaw cyst by fractal analysis.

Materials and Methods

Eighteen patients with a cystic lesion on the jaw were assessed. Panoramic radiographs were taken preoperatively, immediately postoperatively, and 1, 3, 6 and 12 months after cyst enucleation. The images were analyzed by fractal analysis.


The mean fractal dimensions increased immediately after surgery and 3, 6 and 12 months postoperatively. The postoperative 6 and 12 months fractal dimension was similar to the controls.


Fractal analysis was used to overcome the limit of a subjective reading during an assessment of bone regeneration after cyst enucleation.

Keywords: Cyst enucleation; Bone regeneration; Fractal dimension


Fig. 1
Image registration processing by image subtraction tool program (Sunny, Biomedisys Co. Ltd., Seoul, Korea). A, B. Before registration. C, D. Reference point selection. E, F. After registration.
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Fig. 2
Selection of region of interest. A. Selection of lesion region of interest (ROI). B. Selection of control ROI.
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Fig. 3
Image processing. A. Original region of interest image. B. Gaussian blurring. C. Subtract between (A) and (B). D. Add 128. E. Conversion to binary image. F. Erode and dilation. G. Skeletonize.
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Table 1
The change of fractal dimension over time
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Table 2
Comparison with pre-operative fractal dimensions
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Table 3
Comparison with control group fractal dimensions
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