Validity and reliability of palatal rugae morphometric assessment with 3D laser scanned models

Aim

To assess the reliability and validity of morphometric features on 3D digital models produced by scanning maxillary dental casts of Malaysian Malay subjects.

Methods

Dental casts of 20 subjects were scanned using a 3D laser scanner (Next Engine Inc., Santa Monica, California, USA). The palatal rugae morphometric features were assessed on the resulting 3D models using 3-Matic Research 9.0 software (Materialise NV, Heverlee, Belgium). The assessments were repeated by the first and second authors to assess the intra- and inter-examiner reliability, respectively. Rugae morphometric features were also evaluated on the conventional plaster models to assess the validity of the 3D method.

Results

Kappa values of the validity ranged from 0.807 to 0.922 for rugae shape, size category and direction. The intraclass correlation coefficient (ICC) for rugae number validity was 0.979. For intra-examiner reliability, kappa values ranged from 0.716-1.000 for rugae shape, size category and direction. The ICC for rugae number intra-examiner reliability was 0.949. Kappa values of inter-examiner reliability for rugae shape, size category and direction were 0.723-885, while the ICC of rugae number was 0.896.

Conclusion

Palatal rugae analyses on 3D digital models scanned by the 3D Next Engine laser scanner using 3-Matic Research 9.0 software are valid and reliable.

Forensic dentistry; Forensic anthropology; Palate, Imaging, three-dimensional