Imaging Sci Dent.  2016 Mar;46(1):25-31. 10.5624/isd.2016.46.1.25.

Three-dimensional assessment of condylar surface changes and remodeling after orthognathic surgery

• Lee JH
• Lee WJ
• Shin JM
• Huh KH
• Yi WJ
• Heo MS
• Lee SS
• Choi SC

• KMID: 2160154
• DOI: http://doi.org/10.5624/isd.2016.46.1.25

Abstract

PURPOSE
This study was performed to evaluate condylar surface changes and remodeling after orthognathic surgery using three-dimensional computed tomography (3D CT) imaging, including comparisons between the right and left sides and between the sexes.
MATERIALS AND METHODS
Forty patients (20 males and 20 females) who underwent multi-detector CT examinations before and after surgery were selected. Three-dimensional images comprising thousands of points on the condylar surface were obtained before and after surgery. For the quantitative assessment of condylar surface changes, point-to-point (preoperative-to-postoperative) distances were calculated using D processing software. These point-to-point distances were converted to a color map. In order to evaluate the types of condylar remodeling, the condylar head was divided into six areas (anteromedial, anteromiddle, anterolateral, posteromedial, posteromiddle, and posterolateral areas) and each area was classified into three types of condylar remodeling (bone formation, no change, and bone resorption) based on the color map. Additionally, comparative analyses were performed between the right and left sides and according to sex.
RESULTS
The mean of the average point-to-point distances on condylar surface was 0.11±0.03 mm. Bone resorption occurred more frequently than other types of condylar remodeling, especially in the lateral areas. However, bone formation in the anteromedial area was particularly prominent. No significant difference was found between the right and left condyles, but condylar surface changes in males were significantly larger than in females.
CONCLUSION
This study revealed that condylar remodeling exhibited a tendency towards bone resorption, especially in the lateral areas. Condylar surface changes occurred, but were small.

Keyword

Mandibular Condyle; Bone Remodeling; Multidetector Computed Tomography; Imaging, Three-Dimensional

MeSH Terms

Bone Remodeling
Bone Resorption
Female
Head
Humans
Imaging, Three-Dimensional
Male
Mandibular Condyle
Multidetector Computed Tomography
Orthognathic Surgery*
Osteogenesis

Figure

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  Fig. 1 Superimposition of pre- (upper left) and postoperative segmented images (upper right). These images were superimposed over three prominent registration points around the condylar neck (numbers 1, 2, 3). The registered image (lower part) was generated automatically.

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  Fig. 2 A color map of condylar remodeling after orthognathic surgery. Red coloration shows bone formation, blue coloration shows bone resorption, and green coloration shows no change.

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  Fig. 3 The six areas of the condylar head. A, anterior surface; B, superior surface; C, posterior surface; Ant-Lat, anterolateral; Ant-Mid, anteromiddle; Ant-Med, anteromedial; Post-Lat, posterolateral; Post-Mid, posteromiddle; Post-Med, posteromedial.

Reference

1. Bouletreau P, Frey R, Breton P, Freidel M. Focus on the effect of orthognathic surgery on condylar remodeling. Rev Stomatol Chir Maxillofac. 2004; 105:283–288.

2. Park SB, Yang YM, Kim YI, Cho BH, Jung YH, Hwang DS. Effect of bimaxillary surgery on adaptive condylar head remodeling: metric analysis and image interpretation using cone-beam computed tomography volume superimposition. J Oral Maxillofac Surg. 2012; 70:1951–1959.

3. An SB, Park SB, Kim YI, Son WS. Effect of post-orthognathic surgery condylar axis changes on condylar morphology as determined by 3-dimensional surface reconstruction. Angle Orthod. 2014; 84:316–321.

4. Kau CH, Richmond S, Incrapera A, English J, Xia JJ. Three-dimensional surface acquisition systems for the study of facial morphology and their application to maxillofacial surgery. Int J Med Robot. 2007; 3:97–110.

5. Motta AT, de Assis Ribeiro Carvalho F, Cevidanes LH, de Oliveira Almeida MA. Assessment of mandibular advancement surgery with 3D CBCT models superimposition. Dental Press J Orthod. 2010; 15:45e1–45e12.

6. Carvalho Fde A, Cevidanes LH, da Motta AT, Almeida MA, Phillips C. Three-dimensional assessment of mandibular advancement 1 year after surgery. Am J Orthod Dentofacial Orthop. 2010; 137:4 Suppl. S53.e1–S53.e12.

7. Kobayashi T, Izumi N, Kojima T, Sakagami N, Saito I, Saito C. Progressive condylar resorption after mandibular advancement. Br J Oral Maxillofac Surg. 2012; 50:176–180.

8. Xi T, van Loon B, Fudalej P, Berge S, Swennen G, Maal T. Validation of a novel semi-automated method for three-dimensional surface rendering of condyles using cone beam computed tomography data. Int J Oral Maxillofac Surg. 2013; 42:1023–1029.

9. Schilling J, Gomes LC, Benavides E, Nguyen T, Paniagua B, Styner M, et al. Regional 3D superimposition to assess temporomandibular joint condylar morphology. Dentomaxillofac Radiol. 2014; 43:20130273.

10. Cevidanes LH, Bailey LJ, Tucker GR Jr, Styner MA, Mol A, Phillips CL, et al. Superimposition of 3D cone-beam CT models of orthognathic surgery patients. Dentomaxillofac Radiol. 2005; 34:369–375.

11. Arnett GW. A redefinition of bilateral sagittal osteotomy (BSO) advancement relapse. Am J Orthod Dentofacial Orthop. 1993; 104:506–515.

12. Papadopoulou AK, Papachristou DJ, Chatzopoulos SA, Pirttiniemi P, Papavassiliou AG, Basdra EK. Load application induces changes in the expression levels of Sox-9, FGFR-3 and VEGF in condylar chondrocytes. FEBS Lett. 2007; 581:2041–2046.

13. Hwang SJ, Haers PE, Seifert B, Sailer HF. Non-surgical risk factors for condylar resorption after orthognathic surgery. J Craniomaxillofac Surg. 2004; 32:103–111.

14. Komori E, Aigase K, Sugisaki M, Tanabe H. Cause of early skeletal relapse after mandibular setback. Am J Orthod Dentofacial Orthop. 1989; 95:29–36.

15. Van Sickels JE, Larsen AJ, Thrash WJ. Relapse after rigid fixation of mandibular advancement. J Oral Maxillofac Surg. 1986; 44:698–702.