Masticatory Efficiency of Mandibulectomy Patients after Oral Prosthetic Rehabilitation: Preliminary Results

This case series pilot study aimed to test the masticatory efficiency of mandibulectomy patients reconstructed with the free fibula flap using a modified mixing ability test and a digital colorimetric assessment.

Ten healthy dentate volunteers chewed a two-colour chewing gum for 30, 40, and 50 cycles to determine the minimum number of chewing cycles required to achieve consistently at least 90% colour blending (50 cycles). Mandibulectomy patients (n = 6) were given the same chewing gum and separate specimens were collected from the operated and non-operated side after (50 chewing cycles). The masticatory efficiency was assessed by: 1) photometric analysis to calculate the percentage of blended surface; and 2) measuring the colour blending deviation (ΔE) compared to healthy volunteers' master specimen (P < 0.05).

The test group of cancer patients registered a mean 76.75% surface with blended colour after 50 chewing cycles at the non-operated site, and at the operated site (fibula free flap and implant-supported fixed prosthesis) a mean 60.08% blended colour surface was found. The colorimetric analysis revealed significant differences in ΔE values between all the investigated groups (cancer patients operated site < cancer patients non-operated site < healthy patients, P < 0.001).

The qualitative comparison of masticatory efficiency between test and control group of healthy patients showed different values of efficiency, attesting lower masticatory performance for mandibulectomy patients, especially in the operated site of small extent rehabilitation.