Korean J Orthod.  2022 Jan;52(1):53-65. 10.4041/kjod.2022.52.1.53.

Proposed parameters of optimal central incisor positioning in orthodontic treatment planning: A systematic review

• Sangalli L
• Dalessandri D
• Bonetti S
• Mandelli G
• Visconti L
• Savoldi F

• KMID: 2524902
• DOI: http://doi.org/10.4041/kjod.2022.52.1.53

Abstract

Objective
Planning of incisal position is crucial for optimal orthodontic treatment outcomes due to its consequences on facial esthetics and occlusion. A systematic summary of the proposed parameters is presented.
Methods
Studies on Google Scholar^© , PubMed^© , and Cochrane Library, providing quantitative information on optimal central incisor position were included.
Results
Upper incisors supero-inferior position (4–5 mm to upper lip, 67–73 mm to axial plane through pupils), antero-posterior position (3–4 mm to Nasion-A, 3–6 mm to A-Pogonion, 9–12 mm to true vertical line, 5 mm to A-projection, 9–10 mm to coronal plane through pupils), bucco-lingual angulation (4–7° to occlusal plane perpendicular on models, 20–22° to Nasion-A, 57–58° to upper occlusal plane, 16–20° to coronal plane through pupils, 108–110° to anterior-posterior nasal spine), mesio-distal angulation (5° to occlusal plane perpendicular on models). Lower incisors supero-inferior position (41–48 mm to soft-tissue mandibular plane), antero-posterior position (3–4 mm to Nasion-B, 1–3 mm to A-Pogonion, 12–15 mm to true vertical line, 6–8 mm to coronal plane through pupils), bucco-lingual angulation (1-4° to occlusal plane perpendicular on models, 87–94° to mandibular plane, 68° to Frankfurt plane, 22–25° to Nasion-B, 105° to occlusal plane, 64° to lower occlusal plane, 21° to A-Pogonion), mesiodistal angulation (2° to occlusal plane perpendicular on models).
Conclusions
Although these findings can provide clinical guideline, they derive from heterogeneous studies in terms of subject characteristics and reference methods. Therefore, the optimal incisal position remains debatable.

Keyword

Esthetics; Incisors; Cephalometrics; Occlusion

Figure

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  Figure 1 Flow chart illustrating the process of article selection. “not by the author” indicated that the study was not authored by the expected author, but by a homonym author instead.

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