Related Experiment Video
Updated: May 4, 2026

Author Spotlight: 3D Movement Assessment of Maxillary Posterior Teeth in Clear Aligner Treatment
Published on: February 23, 2024
Three-dimensional tooth crown size symmetry in cleft lip and cleft palate
M Okan Akcam1, Halise Aydemir, Levent Özer
1a Professor, Department of Orthodontics, Faculty of Dentistry, University of Ankara, Ankara, Turkey.
Objective:
To evaluate and compare three-dimensional tooth size symmetry in the right and left sides of upper and lower dental arches in cleft lip and palate (CLP) patients and to compare it with an Angle Class I normal occlusion control group.
Materials And Methods:
Dental casts of 72 individuals with CLP (20 bilateral [BCLP], 34 unilateral left [ULCLP], and 18 unilateral right [URCLP]) and 53 individuals with Class I occlusion, all with permanent dentition, were randomly selected. Mesiodistal (MD), labiolingual (LL), and occlusogingival (OG) measurements of upper and lower teeth were recorded with a digital caliper. Descriptive statistics and paired t-test were used for statistical analysis.
Results:
Significant asymmetries were found between the right and left sides of the dental arches in CLP as follows: MD dimension: mandibular first premolar (ULCLP, P < .01); LL dimension: mandibular first premolar (URCLP, P < .05); OG dimension: maxillary central incisor and first premolar (ULCLP, P < .05 and P < .01, respectively), central incisor (BLCLP, P < .01), mandibular canine and first premolar (ULCLP, P < .01), and first molar (ULCLP, P < .05). Tooth crown size asymmetries were also recorded in the Class I group.
Conclusions:
Significant three-dimensional tooth size asymmetries were found in CLP subjects; however, such asymmetries were also present on the Class I control group.
Related Concept Videos
Tooth Anatomy
The Crown, Neck, and Root
The visible part of the tooth is referred to as the crown. It's covered by enamel, the hardest substance in the human body. The crown is uniquely shaped for each type of tooth, allowing for different functions such as cutting, tearing, or...
Teeth
In the bud stage, the tooth germ (an aggregation of cells) starts to form in the developing jawbone. During the cap stage, the tooth germ differentiates into enamel organ, dental papilla, and dental sac, which will later develop into the tooth's enamel, dentin...
Oral Cavity
Teeth: The teeth are the hardest structures in our bodies. Humans have two sets of teeth throughout their lifetime: deciduous (baby) teeth and permanent teeth. Each tooth consists of several parts: the crown (visible part), the root (embedded in the jaw), enamel (hard outer...
Assessment of the Mouth
Mouth Inspection
The inspection begins with visually examining the mouth for symmetry, color, and size.

