Tissue Remodeling After Implantation with Polymethylmethacrylate: An Experimental Study in Mice.

Polymethylmethacrylate (PMMA) is a filler used for aesthetic and/or repair purposes. The response to the implantation of biomaterials varies according to factors related to the patient, the professional responsible for the application and the material used. In vitro and in vivo experimental models have been used to study aspects such as the organism/biomaterial interface and the role of macrophages, dendritic cells and neutrophils. This study aimed to characterize the inflammatory reactions related to polymer concentration, implantation depth and exposure time. Different concentrations of PMMA were implanted in different anatomical planes in mice. The consequences of contact with PMMA, from structural changes to the inflammatory characteristic of tissue damage, were histologically evaluated. The implantation interfered in the morphological structure of the region where it was implanted, expanding it and due to the inflammatory reaction generated, by the presence of the vehicle in the initial phase and by the collagen produced in the chronic phase. The 30% concentration of PMMA induced a greater presence of foreign body giant cells both subcutaneously, at 7, 30 and 90 days after implantation (DAI), and intramuscular at 30DAI. Tissue remodeling was more expressive in the subcutaneous region with significant density of the extracellular matrix at 90DAI. In conclusion, the foreign body reaction resulting from the implantation process acquires different characteristics depending on the anatomical plane and the concentration of implanted product, where the more superficial the implantation plane, the greater the inflammatory reaction. Moreover, PMMA concentration and the depth of implantation did not influence the collagen production.No Level Assigned This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews, and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies, and Experimental Studies. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors https://www.springer.com/00266.

Facial trauma reconstruction with polymethyl methacrylate-A case report.

BACKGROUND: Polymethyl methacrylate (PMMA) is a dermatologic filler commonly used in esthetic procedures. However, it can also be used in more severe cases such as reconstruction of facial traumas. AIMS: The aim of this report was to describe the use of PMMA in a nasal reconstruction of a patient victim of an automobilist accident which presented previous rejection of autograft. PATIENT: A young female patient, 26 y, victim of automobilist accident, with no bone support due to trauma both in the mandibulum and maxilla, presented fracture of several facial bones. Presented rejection of a bone autograft from the skullcap implanted on the nose. In order to harmonize the facial aspect, a nasal fill with PMMA for the anatomic reconstruction of the nose was performed. RESULTS AND CONCLUSIONS: PMMA promoted the recovery of facial and nasal esthetic characteristics of the patient ensuring a satisfactory result.