Novel Tuning of PMMA Orthopedic Bone Cement Using TBB Initiator: Effect of Bone Cement Extracts on Bioactivity of Osteoblasts and Osteoclasts

Abstract

Bone cement containing benzoyl peroxide (BPO) as a polymerization initiator are commonly used to fix orthopedic metal implants. However, toxic complications caused by bone cement are a clinically significant problem. Poly (methyl methacrylate) tri-n-butylborane (PMMA-TBB), a newly developed material containing TBB as a polymerization initiator, was found to be more biocompatible than conventional PMMA-BPO bone cements due to reduced free radical generation during polymerization. However, free radicals might not be the only determinant of cytotoxicity. Here, we evaluated the response and functional phenotypes of cells exposed to extracts derived from different bone cements. Bone cement extracts were prepared from two commercial PMMA-BPO cements and an experimental PMMA-TBB. Rat bone marrow-derived osteoblasts and osteoclasts were cultured in a medium supplemented with bone cement extracts. More osteoblasts survived and attached to the culture dish with PMMA-TBB extract than in the culture with PMMA-BPO extracts. Osteoblast proliferation and differentiation were higher in the culture with PMMA-TBB extract. The number of TRAP-positive multinucleated cells was significantly lower in the culture with PMMA-TBB extract. There was no difference in osteoclast-related gene expression in response to different bone cement extracts. In conclusion, PMMA-TBB extract was less toxic to osteoblasts than PMMA-BPO extracts. Although extracts from the different cement types did not affect osteoclast function, PMMA-TBB extract seemed to reduce osteoclastogenesis, a possible further advantage of PMMA-TBB cement. These implied that the reduced radical generation during polymerization is not the only determinant for the improved biocompatibility of PMMA-TBB and that the post-polymerization chemical elution may also be important.

Conditional Mitigation of Dental-Composite Material-Induced Cytotoxicity by Increasing the Cure Time

“…Thus, cells could not survive as in the previously reported experiment, due to differences in the resistance of the cells to the material components and to the effects of the different methods of eluting the residual components. Chromatographic analysis is necessary to measure the elution of components over time [ 18 , 60 ].…”

“…In light of other potential methods to improve composite materials, N-acetyl cysteine, a precursor of glutathione, the most potent antioxidant in the body, effectively scavenges polymerization radicals and neutralizes chemicals that cause oxidative stress [ 9 , 10 , 15 , 17 , 62 , 63 , 64 , 65 , 66 , 67 , 68 , 69 , 70 , 71 ]. Tri-n-butyl borane, a polymerization initiator, also reduces cytotoxicity, due to the suppressive role of polymerization radicals [ 11 , 13 , 14 , 18 , 33 , 72 ]. These data provide design rules for the use of monomers and initiators to create novel composite materials with higher biocompatibility.…”

“…The polymerization reaction occurs when the photoinitiator is activated by visible-light wavelengths between 450 and 490 nm, followed by the generation of free radicals and the formation of polymers [ 8 ]. Like other polymer-based materials, their chemical composition alters the biological properties and responses of soft tissues [ 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 ]. Many studies have reported cytotoxicity of monomer components, which varies with chemical composition, type, and amount of residual monomer leached [ 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 ].…”

Disparity in the Influence of Implant Provisional Materials on Human Gingival Fibroblasts with Different Phases of Cell Settlement: An In Vitro Study

“…To our knowledge, this is the first study to evaluat influence of provisional materials on cells with different phases of cell settlement. Some studies have shown that material compositions such as monomers, polym zation initiators, and filler particles influence their cytotoxicity [48][49][50][51][52][53][54]. It is known unreacted monomers exert critical biological effects on cells [15,55,56].…”

Ultraviolet Light Treatment of Titanium Microfiber Scaffolds Enhances Osteoblast Recruitment and Osteoconductivity in a Vertical Bone Augmentation Model: 3D UV Photofunctionalization

“…Cells were fixed in 10% formalin and stained with the fluorescent dye rhodamine phalloidin (actin filament, red color; Molecular Probes, Eugene, OR) and 4 ,6-diamidino-2phenylindole (DAPI) (nuclear, blue color; Abcam, Cambridge, UK). Fixing with formalin was proven effective, particularly for immunostaining combined with fluorescent dye in our previous studies [52,118,119].…”