Ideal transverse position of mandibular first molars based on CBCT-derived alveolar bone coverage.
Bone thickness
Orthodontic diagnostics
Radiographic imaging
Transverse tooth position
Journal
Annals of anatomy = Anatomischer Anzeiger : official organ of the Anatomische Gesellschaft
ISSN: 1618-0402
Titre abrégé: Ann Anat
Pays: Germany
ID NLM: 100963897
Informations de publication
Date de publication:
Apr 2022
Apr 2022
Historique:
received:
02
11
2021
revised:
18
01
2022
accepted:
04
02
2022
pubmed:
21
2
2022
medline:
9
3
2022
entrez:
20
2
2022
Statut:
ppublish
Résumé
In orthodontic treatment, transverse arch width often needs to be adjusted to correct anomalies such as posterior crossbite. Ideal transverse arch width at the first molars enabling long-term stability and periodontal health, however, requires sufficient posttreatment bony coverage buccally and orally of the tooth roots. Thus, the aim of this retrospective study was to determine the physiological alveolar bone thickness at the buccal and oral roots of the first mandibular molars in the general population using human CBCT scans assessing local and gender-specific differences. CBCTs of 124 random 11- to 55-year old patients (46 female, 78 male) were analysed retrospectively. Alveolar bone thickness was measured digitally at mesial and distal tooth roots of the first mandibular molars buccally and orally at different vertical positions (4 and 8 mm apically of the cement-enamel-junction CEJ). For each patient, the mean of corresponding measurements from left and right molars was used for analysis. All measurements were reliable, as proven by intrarater- and interrater-reliability-testing. On average, bone thickness increased from the mesial to the distal tooth root, as well as in apical and oral direction. These local differences in alveolar bone thickness were all highly significant at p < 0.0001. Women showed thicker bone buccally at the distal tooth root at 8 mm apically of the CEJ, as well as orally at both mesial and distal tooth roots 4 mm apically of the CEJ. The results of this study suggest that especially in buccal, mesial and gingival direction alveolar bone around mandibular first molars becomes thinner and hence the scope for orthodontic tooth movements is limited. Our results should aid assessing ideal transverse molar position based on alveolar bone coverage, although variations due to age may occur.
Sections du résumé
BACKGROUND
BACKGROUND
In orthodontic treatment, transverse arch width often needs to be adjusted to correct anomalies such as posterior crossbite. Ideal transverse arch width at the first molars enabling long-term stability and periodontal health, however, requires sufficient posttreatment bony coverage buccally and orally of the tooth roots. Thus, the aim of this retrospective study was to determine the physiological alveolar bone thickness at the buccal and oral roots of the first mandibular molars in the general population using human CBCT scans assessing local and gender-specific differences.
METHODS
METHODS
CBCTs of 124 random 11- to 55-year old patients (46 female, 78 male) were analysed retrospectively. Alveolar bone thickness was measured digitally at mesial and distal tooth roots of the first mandibular molars buccally and orally at different vertical positions (4 and 8 mm apically of the cement-enamel-junction CEJ). For each patient, the mean of corresponding measurements from left and right molars was used for analysis.
RESULTS
RESULTS
All measurements were reliable, as proven by intrarater- and interrater-reliability-testing. On average, bone thickness increased from the mesial to the distal tooth root, as well as in apical and oral direction. These local differences in alveolar bone thickness were all highly significant at p < 0.0001. Women showed thicker bone buccally at the distal tooth root at 8 mm apically of the CEJ, as well as orally at both mesial and distal tooth roots 4 mm apically of the CEJ.
CONCLUSIONS
CONCLUSIONS
The results of this study suggest that especially in buccal, mesial and gingival direction alveolar bone around mandibular first molars becomes thinner and hence the scope for orthodontic tooth movements is limited. Our results should aid assessing ideal transverse molar position based on alveolar bone coverage, although variations due to age may occur.
Identifiants
pubmed: 35183706
pii: S0940-9602(22)00023-1
doi: 10.1016/j.aanat.2022.151908
pii:
doi:
Types de publication
Journal Article
Langues
eng
Sous-ensembles de citation
IM
Pagination
151908Informations de copyright
Copyright © 2022 Elsevier GmbH. All rights reserved.
Déclaration de conflit d'intérêts
Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.