IADR Abstract Archives
Mandible Dental Arch Form Determination from CBCT at 3 Levels: A Pilot Study
Objectives: Mandibular dental arch form is divided into 3 different heights to assess surrounding basal structure and the underlying bone width around the apical base. The objective of this research is to evaluate variation of mandibular arch forms at different heights and to determine possibility of developing a standardized clinical arch form.
Methods: 86 CBCTs of patients of a private clinic were screened and 11 fitted in the inclusion criteria of a Class I occlusion and having all their natural teeth. The selected CBCTs then were imported to Mimics software (Materialise NV, Belgium) and they were traced. Each tooth was sliced midsection at 3 different heights: CEJ, Apex and 5mm apical to the apex. Midpoints between the buccal and lingual plates were located for every tooth between and including the first molars. The points were connected forming 3 splines, which then were exported to Geomorph software (cran.r-project.org, Geomorph package, Dean Adams author, Iowa State 2015) for shape analysis and variation detection.
Results: All 3 arch forms can be visualized in 3 dimensions and a different shape of dental arch form can be identified at each level. The variation in the arch form among subjects is significantly smaller in the CEJ level. The variation at apical level is 10 times higher than the variation at CEJ level. This shows that variation in dental arch forms in the subjects increases apically.
Conclusions: Mandibular dental arch form and surrounding bone structure demonstrate more variation apically. It may be concluded that dental arch form variation should be considered when using standardized arch forms for different patients.
Methods: 86 CBCTs of patients of a private clinic were screened and 11 fitted in the inclusion criteria of a Class I occlusion and having all their natural teeth. The selected CBCTs then were imported to Mimics software (Materialise NV, Belgium) and they were traced. Each tooth was sliced midsection at 3 different heights: CEJ, Apex and 5mm apical to the apex. Midpoints between the buccal and lingual plates were located for every tooth between and including the first molars. The points were connected forming 3 splines, which then were exported to Geomorph software (cran.r-project.org, Geomorph package, Dean Adams author, Iowa State 2015) for shape analysis and variation detection.
Results: All 3 arch forms can be visualized in 3 dimensions and a different shape of dental arch form can be identified at each level. The variation in the arch form among subjects is significantly smaller in the CEJ level. The variation at apical level is 10 times higher than the variation at CEJ level. This shows that variation in dental arch forms in the subjects increases apically.
Conclusions: Mandibular dental arch form and surrounding bone structure demonstrate more variation apically. It may be concluded that dental arch form variation should be considered when using standardized arch forms for different patients.