The Use of Light/Chemically-Hardened Poly-Methyl-Methacrylate, Poly-Hydroxyl-Ethyl-Methacrylate and Calcium Hydroxide Graft Material in Combination with Polyanhydride around Implants and Extraction Sockets in Minipigs: Part II: Histological and μCT Evaluations

Methods: Light-hardened poly-methyl-methacrylate, poly-hydroxyl-ethyl-methacrylate, and calcium hydroxide plus polyanhydride (PPCH+PA) composite graft), PPCH graft alone, PA graft alone, were compared to each other and to a no graft control group. All mandibular premolar teeth were extracted; a total of 48 implants were placed into sockets of the mesial roots in three minipigs. Crestal areas and intrabony spaces were randomly augmented with graft materials or left untreated. Distal sockets not receiving implants and the sockets of first molars (n=60) were randomly treated with one of graft materials or left empty. In addition, two molar sockets were treated with original PMMA/PHEMA and calcium hydroxide (PPCH) graft material. Quantitative microcomputed tomography (μCT) was used to assess alveolar bone structure and tissue compositions following crestal augmentations. Histological evaluations included descriptive histology to assess the peri-implant wound healing as well as histomorphometric measurements to determine bone-to-implant contact (BIC).