LAUSR

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), mesio-distal 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.