IADR Abstract Archives

Validation of Shape Correspondence for Quantification of Condylar Resorption

Objectives:  Condylar resorption has been correlated with limited mobility of the TMJ and pain.  However, there is no validated method for the quantifying discrete changes in condylar morphology.  To achieve this, the objective of this cross-sectional study was to use simulated resorption on 3D cone beam CT (CBCT) models to validate a novel analytical tool known as Shape Correspondence. We hypothesized the agreement between the simulated defects and the measurements made of these defects would be within 0.5mm (the image's spatial resolution).

 

Methods:  One hundred seventy nine discrete bony defects measuring 3mm and 6mm were simulated on the surfaces of 3D models derived from CBCT images of asymptomatic patients using ITK-Snap software.  The size of each simulated defect was analyzed using Shape Correspondence and the values obtained compared to the true defect size.    

 

Results:

Three statistical methods were used to analyze the accuracy of Shape Correspondence: (1) the probability that the sample mean is within 0.5mm of the true defect size (P(|X-µ0|<0.5)), (2) 95% confidence interval (CI), and (3) 95% prediction interval (PI). All analyses were based on the assumption of a normal distribution for this population.

3Center(C)

3Medial(M)

3Lateral(L)

3CML(C)

3CML(M)

3CML (L)

3CML (Avg)

6C

0.9999

0.9999

0.9999

0.9998

0.9983

0.9996

0.9999

0.9645

95% CI

2.6020  2.9993

2.6770  3.0850

2.5269  2.9302

2.7508  3.1798

2.4263  2.9478

2.4556  2.9117

2.6143  2.9650

5.6486  6.4662

95% PI

1.9122  3.6892

1.9817  3.7803

1.8171  3.6413

2.0278  3.9029

1.5564  3.8177

1.7009  3.6664

2.0225  3.3153

4.9277  7.1871

Conclusions:  This study validated Shape Correspondence as a method to precisely and predictably quantify 3D condylar resorption. Future studies using Shape Correspondence can longitudinally map the stages of disease progression of TMJ Osteoarthritis and identify morphological variants or subtypes which may explain the heterogeneity of the clinical presentation.

Support: NIDCR DE-017727, DE-018962; AADR Student Research Fellowship

 


AADR/CADR Annual Meeting
2010 AADR/CADR Annual Meeting (Washington, D.C.)
Washington, D.C.
2010
1200
  • Walker, David  ( University of North Carolina, Chapel Hill, NC, USA )
  • Cevidanes, Lucia  ( University of North Carolina, Chapel Hill, NC, USA )
  • Paniagua, Beatriz  ( University of North Carolina, Chapel Hill, NC, USA )
  • Zhu, Hongtu  ( University of North Carolina, Chapel Hill, NC, USA )
  • Styner, Martin  ( University of North Carolina, Chapel Hill, NC, USA )
  • Lim, Pei Feng  ( University of North Carolina, Chapel Hill, NC, USA )
  • Poster Session
    TMJ
    03/05/2010