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Published on: September 8, 2023
The relationship between third molar agenesis and craniofacial morphology: a systematic review and meta-analysis
Yushi Le1,2, Mingjuan Li1,2, Feng Li1,2
1State Key Laboratory of Oral & Maxillofacial Reconstruction and Regeneration, Key Laboratory of Oral Biomedicine Ministry of Education, Hubei Key Laboratory of Stomatology, School & Hospital of Stomatology, Wuhan University 430079, China.
Background:
Agenesis of third molar agenesis has a higher incidence than other tooth development anomalies. Previous research identified a potential correlation between third molar agenesis and specific craniofacial morphology; however, no systematic review and meta-analysis on this topic currently exists.
Objective:
The objective of this systematic review and meta-analysis was to evaluate the association between third molar agenesis and craniofacial sagittal and vertical morphology.
Search Methods:
An electronic search was conducted on PubMed, Embase, Web of Science, and the Cochrane Library without restrictions on publication year or language; this was supplemented by the manual retrieval of relevant literature.
Selection Criteria:
Cross-sectional studies that compared craniofacial morphology using angular and linear measurements obtained from lateral cephalography between patients with third molar agenesis and those without were included.
Data Collection And Analysis:
The quality assessment of the enrolled articles was evaluated by the Joanna Briggs Institute critical appraisal tool. Meta-analysis and sensitivity analysis were performed by Review Manager software (The Cochrane Collaborative, version 5.4, Cochrane IMS).
Results:
A total of seven studies were included. Meta-analysis demonstrated that the ANB (mean differences (MD) = -0.75, 95% CI: -1.31 to -0.19, P < 0.01), palate length (ANS-PNS, MD = -1.68, 95% CI: -2.24 to -1.11, P < 0.01), and mandibular length (Go-Pog, MD = -0.36, 95% CI: -0.59 to -0.13, P < 0.01) were smaller in patients with third molar agenesis. With regard to vertical craniofacial morphology, the mandibular plane angle (MP-FH; MD = -1.88, 95% CI: -3.45 to -0.31, P = 0.02), gonial angle (gonial angle; MD = -1.73, 95% CI: -2.69 to -0.77, P < 0.01) and lower face height (lower face heigh angle; MD = -1.36, 95% CI: -1.94 to -0.77, P < 0.01) were smaller in patients with third molar agenesis, indicating a flatter or brachyfacial skeletal pattern.
Conclusions:
The results of this study suggest that third molar agenesis maybe associated with a reduced maxillary length and a flatter mandible. However, these findings need to be interpreted with caution due to inconsistencies in the certainty of evidence.
Clinical Trial Registration:
PROSPERO (CRD42023448226).
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