Introduction:
Rehabilitation after resection of hard or soft palate is best accomplished prosthodontically through obturator. However, restoring normal phonation, particularly a reduction in nasalence of speech is indeed, a daunting task, since the defect configuration may render complete obturation impossible.

Aim of the study:
To create an algorithm to predetermine the effectiveness of obturator prosthesis in reducing hypernasality in maxillectomy patients.

Material and methods:
57 patients (39 male, 18 female) with healed maxillary defects were included in the study. All the patients were wearing definitive obturator for at least 3 months. The volume of the maxillary defect was obtained using CBCT. The percentage nasality and resonating frequency were calculated with the help of PRAAT software. Both the parameters were assessed with and without obturator.

Results:
There was a decrease in resonating frequency with obturator use (r= -0.443). On evaluating the correlation between percentage resonance with obturator and diameter of defect opening and internal diameter of the defect using regression analysis, following equation was generated: % resonance with obturator = 15.635 -0.667 X Diameter of defect opening +0.499 X maximum internal diameter of the defect.

Conclusions:
With the present algorithm, one can predetermine the value of hypernasality depending upon the defect size prior to obturator fabrication enabling surgeons and prosthodontics better diagnosis and treatment planning.