Objectives:This research was carried out to evaluate radiographically the effect of different
denture base materials “poly methyl methacrylate base (PMMA) processed by conventional technique versus thermoplastic biocompatible (polyan IC ) base processed by injectable mold technique on the supporting structures of the mini implant retained mandibular overdenture using CBCT.
Materials and Methods: Fourteen edentulous patients with a mean age of 55 year were selected to participate in this study. Inclusion criteria were: U-shaped alveolar arches, Angle class I ridge relationship, adequate inter arch space. Exclusion criteria were: Patients having systemic diseases affecting bone metabolism, patients having parafunctional habits, patients suffering from neuromuscular disorders, and temporomandibular joint disorders. Un-controlled diabetes. For all the selected patients, mucosa supported maxillary complete denture and mini-implant retained mandibular over denture by four mini- implants installed in the interforaminal region. Patients participating in this study were randomly divided into two equal groups according to the denture base materials, Group 1:Seven patients were rehabilitated with upper conventional acrylic resin complete denture and lower mini-implant retained mandibular overdenture processed by the conventional technique Group 2:Seven patients were rehabilitated with upper conventional acrylic resin complete denture and lower mini-implant retained mandibular overdenture processed by injectable technique.
Results: In this study, at the end of the follow up period there was statistically significant difference of peri-implants bone changes between group 1 (conventional technique) and group 2 ( injectable technique). The least bone loss was reported around the implants in group 2.