Clinical Evaluation of the Nasopalatine Canal in Implant-Prosthetic Treatment: A Pilot Study

Abstract

Implant-prosthetic rehabilitation of missing teeth in the anterior maxilla is often challenging due to ongoing bone resorption and remodeling events and may require regeneration procedures involving the nasopalatine canal (NPC). We describe a surgical approach with a block graft in relation to the NPC and evaluate clinical performance, sensory perception, and aesthetic result of the implant-prosthetic treatment over a two- to nine-year (mean: 3.5 years) follow-up. Ten implants (six in the right central incisor and four in the left central incisor) were, respectively, placed in 10 consecutive patients with bone defects affecting the NPC and unfavorable widening of the incisive foramen. Treatment stages included: (1) Diagnosis: evaluation of clinical-aesthetic parameters using Cone Beam Computed Tomography; (2) Surgery: block graft placement by palatine and incisal with simultaneous guided bone regeneration, and late (6–10 months) implant placement; (3) Prosthetics: placement of a screw-retained crown (torque of 32 N/cm). At treatment initiation, all the NPCs evaluated in our study were free of pathologies. Treatment evaluation included bone crest thickness, neurosensory status, patients’ treatment perception, and pink and white aesthetic scores (PES/WES). Pre-surgery, anterior ridge thickness at the level of the incisive foramen was (mean ± SD) 3.5 ± 2 mm, 5.4 ± 1.5 mm, and 6.1 ± 1.9 mm at heights of 4, 8, and 14 mm apical to the marginal bone crest, respectively. Post-treatment values were, respectively, 10.1 ± 2.0 mm, 10.5 ± 1.0 mm, and 13.4 ± 3.0 mm. The perception of treatment with the aesthetic pink and white indices (PES/WES) was an average of 7.5 and 7 points, respectively, out of a total of 10 each index, with a recovery of 100% of the neurosensory perception of the area. We propose that bone augmentation using block and particulate graft material can compensate for anatomical variations in the NPC, optimize implant’s three-dimensional positioning and improve facial contour, providing tissue and implant stability and good aesthetic outcomes.