Related Experiment Video
Updated: May 21, 2026

Precision of In Vivo Quantitative Tooth Wear Measurement Using Intra-Oral Scans
Published on: July 12, 2022
Does incisor inclination change during orthodontic treatment affect gingival thickness and the width of keratinized
Dimitrios Kloukos1,2,3, George Koukos4, Ioannis Doulis2
1Department of Orthodontics and Dentofacial Orthopedics, School of Dental Medicine, University of Bern, Freiburgstrasse 7, CH-3010 Bern, Switzerland.
Objective:
This prospective controlled study aimed to assess whether changes in mandibular incisor inclination during orthodontic treatment with fixed appliances affect gingival thickness (GT) and the width of keratinized gingiva (WKG), and having as reference an untreated group of participants.
Materials And Methods:
Forty consecutively recruited adult orthodontic patients and 40 untreated volunteers, matched for age and gender and selected from the same background population serving as controls, were included. Mandibular incisor inclination was measured in lateral cephalograms before treatment commencement (T0) and 1 month before fixed appliances' removal (T1). Gingival thickness was measured using an Ultrasound Device (US) and width of keratinized gingiva (WKG) using a standard periodontal probe within the frames of a full periodontal examination at T0, T1, and 1 year after bracket removal (T2), that is, at about 30 months from T1.
Results:
Nineteen females and 21 males in each group [mean age in years (range): intervention group 23.1 (16.8-43.3); control: 21.85 (18.2-43.9)] were analysed. Overall, change in incisor proclination [mean change in Incisor Mandibular Angle Plane-IMPA (ΔIMPA) was 6.35° (SD 5.08°)] was not associated with any significant change in soft tissue thickness and with alterations in WKG. The group receiving fixed appliances did not exhibit thickening or thinning of GT in comparison to the control group; the WKG was reduced in the intervention group in comparison to the untreated group, where it essentially remained unchanged (#41: coeff.: -0.29, P value: .1, 95% CIs: -0.65, 0.06; #31: coeff.: -0.51, P value: .01, 95% CIs: -0.88, -0.14).
Conclusions:
Lower incisor proclination during orthodontic treatment does not appear to significantly alter GT and WKG, but orthodontic treatment, overall, leads to reduction of the WKG.
Related Concept Videos
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 and...
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 grinding food.

