Limits...
Effect of additive particles on mechanical, thermal, and cell functioning properties of poly(methyl methacrylate) cement.

Khandaker M, Vaughan MB, Morris TL, White JJ, Meng Z - Int J Nanomedicine (2014)

Bottom Line: We found that flexural strength and fracture toughness were significantly greater for PMMA specimens that incorporated silica than for the other specimens.All additives prolonged the time taken to reach maximum curing temperature and significantly improved cell adhesion of the PMMA samples.The results of this study could be useful for improving the union of implant-PMMA or bone-PMMA interfaces by incorporating nanoparticles into PMMA cement for orthopedic and orthodontic applications.

View Article: PubMed Central - PubMed

Affiliation: Department of Engineering and Physics, University of Central Oklahoma, Edmond, OK, USA.

ABSTRACT
The most common bone cement material used clinically today for orthopedic surgery is poly(methyl methacrylate) (PMMA). Conventional PMMA bone cement has several mechanical, thermal, and biological disadvantages. To overcome these problems, researchers have investigated combinations of PMMA bone cement and several bioactive particles (micrometers to nanometers in size), such as magnesium oxide, hydroxyapatite, chitosan, barium sulfate, and silica. A study comparing the effect of these individual additives on the mechanical, thermal, and cell functional properties of PMMA would be important to enable selection of suitable additives and design improved PMMA cement for orthopedic applications. Therefore, the goal of this study was to determine the effect of inclusion of magnesium oxide, hydroxyapatite, chitosan, barium sulfate, and silica additives in PMMA on the mechanical, thermal, and cell functional performance of PMMA. American Society for Testing and Materials standard three-point bend flexural and fracture tests were conducted to determine the flexural strength, flexural modulus, and fracture toughness of the different PMMA samples. A custom-made temperature measurement system was used to determine maximum curing temperature and the time needed for each PMMA sample to reach its maximum curing temperature. Osteoblast adhesion and proliferation experiments were performed to determine cell viability using the different PMMA cements. We found that flexural strength and fracture toughness were significantly greater for PMMA specimens that incorporated silica than for the other specimens. All additives prolonged the time taken to reach maximum curing temperature and significantly improved cell adhesion of the PMMA samples. The results of this study could be useful for improving the union of implant-PMMA or bone-PMMA interfaces by incorporating nanoparticles into PMMA cement for orthopedic and orthodontic applications.

Show MeSH

Related in: MedlinePlus

Fluorescent microscope images of different kinds of bone cements used during cell proliferation tests. (A) PMMA, (B) PMMA with MgO, (C) PMMA with HAp, (D) PMMA with CS, (E) PMMA with BaSO4, and (F) PMMA with SiO2.Abbreviations: CS, chitosan; HAp, hydroxyapatite; MgO, magnesium oxide; PMMA, poly(methyl methacrylate); BaSO4, barium sulfate; SiO2, silica.
© Copyright Policy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4043713&req=5

f8-ijn-9-2699: Fluorescent microscope images of different kinds of bone cements used during cell proliferation tests. (A) PMMA, (B) PMMA with MgO, (C) PMMA with HAp, (D) PMMA with CS, (E) PMMA with BaSO4, and (F) PMMA with SiO2.Abbreviations: CS, chitosan; HAp, hydroxyapatite; MgO, magnesium oxide; PMMA, poly(methyl methacrylate); BaSO4, barium sulfate; SiO2, silica.

Mentions: No proliferation in the cement samples was found, except for a few cells (Figure 8). However, there were many instances of paired cells being found close together, suggesting cell division had occurred. It would have been better to run at least a 24-hour proliferation assay to confirm that some of the cells were dividing. Proliferation tests were conducted for an hour since the osteoblasts on a coverslip showed a good degree of proliferation (about 50%) after an hour. These results suggest that it may take longer for cells to become accustomed to the bone matrix material than for cells to acclimate to coverslips.


Effect of additive particles on mechanical, thermal, and cell functioning properties of poly(methyl methacrylate) cement.

Khandaker M, Vaughan MB, Morris TL, White JJ, Meng Z - Int J Nanomedicine (2014)

Fluorescent microscope images of different kinds of bone cements used during cell proliferation tests. (A) PMMA, (B) PMMA with MgO, (C) PMMA with HAp, (D) PMMA with CS, (E) PMMA with BaSO4, and (F) PMMA with SiO2.Abbreviations: CS, chitosan; HAp, hydroxyapatite; MgO, magnesium oxide; PMMA, poly(methyl methacrylate); BaSO4, barium sulfate; SiO2, silica.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4043713&req=5

f8-ijn-9-2699: Fluorescent microscope images of different kinds of bone cements used during cell proliferation tests. (A) PMMA, (B) PMMA with MgO, (C) PMMA with HAp, (D) PMMA with CS, (E) PMMA with BaSO4, and (F) PMMA with SiO2.Abbreviations: CS, chitosan; HAp, hydroxyapatite; MgO, magnesium oxide; PMMA, poly(methyl methacrylate); BaSO4, barium sulfate; SiO2, silica.
Mentions: No proliferation in the cement samples was found, except for a few cells (Figure 8). However, there were many instances of paired cells being found close together, suggesting cell division had occurred. It would have been better to run at least a 24-hour proliferation assay to confirm that some of the cells were dividing. Proliferation tests were conducted for an hour since the osteoblasts on a coverslip showed a good degree of proliferation (about 50%) after an hour. These results suggest that it may take longer for cells to become accustomed to the bone matrix material than for cells to acclimate to coverslips.

Bottom Line: We found that flexural strength and fracture toughness were significantly greater for PMMA specimens that incorporated silica than for the other specimens.All additives prolonged the time taken to reach maximum curing temperature and significantly improved cell adhesion of the PMMA samples.The results of this study could be useful for improving the union of implant-PMMA or bone-PMMA interfaces by incorporating nanoparticles into PMMA cement for orthopedic and orthodontic applications.

View Article: PubMed Central - PubMed

Affiliation: Department of Engineering and Physics, University of Central Oklahoma, Edmond, OK, USA.

ABSTRACT
The most common bone cement material used clinically today for orthopedic surgery is poly(methyl methacrylate) (PMMA). Conventional PMMA bone cement has several mechanical, thermal, and biological disadvantages. To overcome these problems, researchers have investigated combinations of PMMA bone cement and several bioactive particles (micrometers to nanometers in size), such as magnesium oxide, hydroxyapatite, chitosan, barium sulfate, and silica. A study comparing the effect of these individual additives on the mechanical, thermal, and cell functional properties of PMMA would be important to enable selection of suitable additives and design improved PMMA cement for orthopedic applications. Therefore, the goal of this study was to determine the effect of inclusion of magnesium oxide, hydroxyapatite, chitosan, barium sulfate, and silica additives in PMMA on the mechanical, thermal, and cell functional performance of PMMA. American Society for Testing and Materials standard three-point bend flexural and fracture tests were conducted to determine the flexural strength, flexural modulus, and fracture toughness of the different PMMA samples. A custom-made temperature measurement system was used to determine maximum curing temperature and the time needed for each PMMA sample to reach its maximum curing temperature. Osteoblast adhesion and proliferation experiments were performed to determine cell viability using the different PMMA cements. We found that flexural strength and fracture toughness were significantly greater for PMMA specimens that incorporated silica than for the other specimens. All additives prolonged the time taken to reach maximum curing temperature and significantly improved cell adhesion of the PMMA samples. The results of this study could be useful for improving the union of implant-PMMA or bone-PMMA interfaces by incorporating nanoparticles into PMMA cement for orthopedic and orthodontic applications.

Show MeSH
Related in: MedlinePlus