Root Regeneration with Photobiomodulation of an Upper Lateral Incisor Associated with Root Resorption Due to an Impacted Maxillary Canine: A Case Report.

Objective: To present a case report of maxillary lateral incisor root regeneration after severe root resorption, treated with photobiomodulation (PBM). Background: Impacted maxillary canines often come with the risk of maxillary lateral incisor root resorption, which is widely recognized as the predominant adverse effect in these situations. This progressive process of root resorption is currently irreversible, with no known way to reverse it. Materials and methods: A male patient was 14 years old. Radiographically it was observed that canine 23 is impacting against the root of 22 producing signs of root resorption and having a less than 1:1 crown-to-root ratio with mobility grade 1. From the beginning of the treatment, PBM-assisted orthodontics was proposed. To address the patient's dental concerns, the treatment plan outlined the extraction of the deciduous upper left canine tooth leaving the lateral as long as possible in the mouth. During each appointment, PBM was applied with a diode laser. The wavelength was 810 nm, Ap = 0.2 W, 4.4 J, 22 sec every 21 days, 13 applications in total (57.2J), with a 400 μm inactive surgical tip, in a scanning movement, 1 mm from the mucosa while moving following the vestibular surface of the upper left lateral and canine roots. Results: After 12 months, the 22 had root neoformation and complete closure of the apex with vitality. Conclusions: PBM with an 810 nm diode laser in this clinical case promoted root regeneration of an upper lateral incisor, with severe root resorption, owing to an impacted maxillary canine while still vital.