Aim: To assess the impact of definitive maxillary obturator prostheses on oral health-related quality of life (OHRQol). Materials and Methods: A presented prospective study comprising 50 patients with maxillectomy defects was selected for the study. Patients with any active or persistent lesion in relation to the defect site, restrictive mouth opening along with poor general health were excluded from the study. All the patients were rehabilitated with definitive maxillary obturator prostheses, respectively. These patients were subjected for assessment of OHRQol and obturator prostheses functioning. These assessments were done using three scales OHIP-Edent-19, obturator functioning scale (OFS-15) and a novel scale—maxillofacial prosthesis performance scale (MFPPS). The assessment was done on all the patients after 2 weeks and 3 months of prosthesis function. The data were tabulated and analysed using paired sample t-test and the Wilcoxon signed rank test for paired groups and unpaired sample t-test for independent groups. Results: The scores of OHIP-Edent, OFS and MFPPS for definitive maxillary obturator prostheses after 2 weeks were 37.56, 30.48 and 20.50. The scores of OHIP-Edent, OFS and MFPPS for definitive maxillary obturator prostheses after 3 months were 30.30, 24.26 and 16.10, respectively. Conclusion: Mean differences of OHIP-Edent (7.260), OFS (6.220) and MFPPS (4.400) were observed after 2 weeks and 3 months of obturator prosthesis function. These findings show significant improvements of prosthesis in terms of functional, physical, psychological and social parameters after long-term follow-up (3 months). © 2023 Elsevier B.V., All rights reserved.