Role of residual mandibular teeth after computer-assisted mandibular reconstruction using a fibular flap.

Background: Computer-assisted mandibular reconstruction after mandibulectomy enables accurate reconstruction of the occlusal positions between the maxilla and mandible. Understanding the remaining teeth condition is essential for sensory mastication in patients with numerous tooth loss. However, no studies have examined the dental status of the remaining mandible after computer-assisted mandibular reconstruction using a fibular flap. This study evaluated the role of residual teeth and other factors in effective acquisition of oral intake after computer-assisted mandibular reconstruction using a fibular flap. Patients and Methods: Postoperative oral intake and associated factors were retrospectively examined in 57 consecutive patients. Oral intake was assessed using the Functional Oral Intake Scale. Multivariate analysis was performed to evaluate the remaining teeth arrangement (Eichner's classification), mandibular dentures, extent of resection (Brown's classification), age, performance of glossectomy, history of radiation therapy, and computer-assisted methods. Results: Multivariate analysis revealed that Eichner's classification had a positive (p<0.001) and radiation therapy had a negative (p<0.05) impact on oral intake. The patients with dentures anchored to the remaining teeth in the occlusal support area (i.e., premolar and molar) had higher Functional Oral Intake score than those with dentures anchored to the remaining teeth in the non-occlusal support area (6.78±0.03 vs. 6.10±0.07, p<0.005). Conclusion: In computer-assisted mandibular reconstruction with accurate occlusion, the residual teeth in the occlusal support area are essential for good postoperative oral intake with dentures. During mandibulectomy, if oncologically acceptable, these teeth should be preserved, and selective placement of dental implants in the occlusal support area should be considered.