تقييم التوافق الحيوي والخواص الميكانيكية لسيليكون الوجه والفكين معزز بجزيئات نيتريد البورون السداسية == Evaluating the Biocompatibility and Mechanical Properties of Maxillofacial Silicone Enhanced by Hexagonal Boron Nitride Particles
Author name:
منتظر سلام علي
Supervisor name:
فائزة محمد حسين عبد الامير
General topic:
Dentistry
Specific topic:
Prosthodontics
Degree:
Master
University:
University of Baghdad
Language:
English
University location:
Baghdad
Key words:
- Maxillofacial prostheses
- Maxillofacial silicone
- Biocompatiblity
- Mechanical properties
- Hexagonal boron nitride
First pages:
T102742 - p.pdf
Abstract:
Maxillofacial silicone is the most popular material in the fabrication of maxillofacial prostheses. However, the material did not meet the desired qualities of maxillofacial prosthesis due to mechanical properties limitations. This study aims to evaluate maxillofacial silicone’s biocompatibility after the addition of hexagonal boron nitride (H-BN) particles concerning cytotoxicity and skin irritation, as well as its mechanical properties. Methodology: Eighteen specimens of maxillofacial silicone (VST-50F) incorporated with different percentages of H-BN (0, 0.1, 0.3, 0.5, 0.7, and 1 wt%) were tested for cytotoxicity in vitro by direct contact test. Then, cell viability was determined by cytotoxicity assay. Twelve specimens were applied in vivo to the backs of five rabbits for 4 hours, followed by evaluations of the skin irritation. The experimental groups (control, 0.5 wt%, and 0.7 wt%) were selected after the pilot study. 10 specimens out of 120 specimens were utilized to assess each mechanical property (tear strength, tensile strength, elongation percentage, Shore A hardness, and surface roughness). The specimens were studied using field emission-scanning electron microscope (FE-SEM) with energy dispersive X-ray spectroscopy (EDX) and Fourier transform infrared spectroscopy (FTIR). One-way ANOVA and Tukey’s tests were used to assess the data, with P-value < 0.05 indicating statistical significance. Results: The results revealed a negligible effect of the modified maxillofacial silicone to the cell viability after 72 hours of incubation and there was no skin irritation. The FE-SEM and EDX findings showed evenly dispersed H-BN within the VST-50F silicone. The FTIR revealed no chemical interaction between the silicone and H-BN. Both experimental groups showed a significant increase in tear strength and a significant decrease in Shore A hardness and surface roughness. The 0.5 wt% group showed a non-significant drop in tensile strength and elongation percentage. However, the 0.7 wt% group showed a significant decline. Conclusion and recommendations: This study suggests that maxillofacial silicone is safe up to 1 wt% of H-BN in terms of cytotoxicity and skin irritation. As the percentages of H-BN increased, tear strength improved, whereas tensile strength, elongation percentage, Shore A hardness, and surface roughness were reduced. However, the remaining biocompatibility tests need to be investigated before being used on humans.
Full text:
361f94374d.pdf
Summary:
c1aa692d9f.pdf
References:
a5a1bca504.pdf
