The upper lateral incisor is, after the premolars, among the teeth most frequently absent through agenesis, and it lies in the zone of greatest aesthetic value. The clinical decision comes down to two routes, to be chosen case by case.
Orthodontic space closure. Orthodontics moves the canine into the lateral incisor position, reshaping it, and closes the space. Where feasible it is often the more conservative choice: it avoids a lifelong prosthesis and is favourable on the periodontal level. Systematic reviews show no clear aesthetic difference compared with implant replacement, and in several analyses space closure is rated favourably.
Space opening and replacement. When occlusion, profile or dental relationships do not make closure indicated, the space is maintained and the tooth is replaced with an implant or, in selected cases, a minimally invasive resin-bonded bridge. Conventional tooth-supported prostheses tend to worse periodontal outcomes than closure.
What guides the choice
Type of occlusion and bite, colour and shape of the canine, amount of bone at the site, age and growth, patient expectations. For the implant, one often underestimated point: the agenesis site frequently has a thin ridge, which requires a strategy for the bone deficit.
Timing
In growing patients the implant is postponed until skeletal growth is complete.
Does the canine in the lateral incisor position show? With careful reshaping the result is natural; assessing the colour and shape of the canine is part of the initial decision.
Related reading
References: PubMed 27476355; network meta-analysis PubMed 39667155. Informational disclaimer. Author: Dr. Gaetano Calesini.