Real-time in vitro measurement of denture-mucosa pressure distribution in a typical edentulous patient with and without implants: Development of a methodology

Purpose: To measure the pressure distribution on the oral mucosa in vitro by comparing the pressure distributions under a complete denture and that of an implant overdenture. Materials and method: Anatomically accurate models and conventional Class I complete denture (CD) were produced and subjected to cyclic loading using a 100 N vertical centric and unilateral masticatory load with the universal testing machine (Instron 3369). Four miniature pressure sensors were positioned at four different locations in the intaglio surface of the denture and recorded pressure at 100 Hz frequency measured during a 10cycle load at 1 Hz. Testing was repeated in different clinical combinations; CD vs. single implant overdentures (1IOD), CD vs. two, three and four implant overdentures (2-IOD, 3-IOD vs. 4-IOD). The pressure profile (kPa) of complete dentures were measured and compared to the implant overdenture combinations. Collected data was statically analysed using SPSS and one-way analysis of variance. Results: The highest mean pressure was observed in CD group, with the mean mandible buccal ridge pressure value of 212.82 kPa +/- 136.9 due to its surface area. There were no statistically significant differences between the group combinations (p = 0.146) but between various locations in the mean pressure recorded across the five denture/overdenture combinations. Conclusion: CD experienced large pressure values on mandibular denture. 1-IOD demonstrated the most pressure in comparison to CD where with an increase in the number of implants used, it transformed the denture from being pure-borne mucosa to an implant overdenture, providing support and distributing the pressure amongst the implants.