Author: Farah Abdul Razzaq Al-Bazaz
The Impact of CO2 Laser and Hydroxyapatite Nano Particles on Dental
Abstract: Background: Laser technology holds great promise for medical and dental applications and carbon dioxide (CO2) laser is still one of the most beneficial type. A laser beam is created from a substance known as an active medium, which when stimulated by light or electricity produces photons of a specific wavelength. This beam results in an interaction between light and biological constituents of tissues that are converted into heat; ending with structural and chemical changes in tissues. Dental caries is a dietary carbohydrate-modified bacterial infectious disease. The basic mechanism of dental caries is demineralization through the acids attack. Lasers are expected to be one of the most promising new technical modalities for the treatment of dental diseases. Nanotechnology is “the manipulation of matter on the molecular and atomic levels. The developed interest for nanotechnology in many fields, is producing interesting and imminent applications as tissue repair and replacement especially in bones and dental mineralized tissues. Aim of the study: this study was conducted to test the impact of CO2 laser and Hydroxyapatite nanoparticles on the change in chemical composition of enamel and the morphological changes in enamel ultra-structure. Materials and Methods: Teeth samples in this study consisted of 66 maxillary first premolars, divided into six groups: one control group and five study groups, each group consisted of 11 teeth; one tooth for Scanning Electron Microscope examination (SEM), while other 10 teeth for Energy dispersive spectroscopy (EDS) analysis.A position of circular window on the buccal surface of each tooth was standardized. To induce caries lesion on enamel surface, pH cycling procedure was followed. Lasing was carried out using CO2 laser system at specific power, time and mode. Hydroxyapatite nanoparticles used in the study was 20nm, the concentration was determined to be 10%. The weight percentages (wt%) of Calcium, Phosphorus, Oxygen were determined using EDS analysis to evaluate the change in chemical composition of enamel; SEMwas used to demonstrate the morphological changes in enamel ultra-structure. Results: For all groups, the data obtained by (EDS) analysis revealed that for both Calcium (Ca) and Phosphorus (P), the mean atomic percentage was reduced after demineralization and after laser irradiation. An increase in the atomic percentage for both elements after treatment with other agents was noticed, with the maximum value recorded for the group treated with Laser + hydroxyapatite nanoparticles. For Oxygen (O), the result was opposite to that of (Ca) and (P). Statistical analysis werehighly significant (p>0.01) for all of the three elements. Examination of enamel surface using SEM revealed an ultrastructural change had occurred beginning with loss of enamel normal architecture after demineralization. After CO2 laser irradiation, cracks and melted and recrystallized areas were noticed. After treatment with hydroxyapatite nanoparticles, hydroxyapatite nanoparticles + CO2 laser and CO2 laser + hydroxyapatite nanoparticles most of micropores were occluded and surface defects were reconstructed. Conclusion: Treatment of enamel surface with CO2 laser + hydroxyapatite nanoparticles gave the best result regarding EDS analysis and SEM examination, so such treatment could be considered as a method of preventing demineralization and encouraging remineralization of enamel. Keywords: CO2 laser, hydroxyapatite nanoparticles, EDS analysis, SEM examination http://DOI: 10.21275/ART20176224
The Effect of CO2 LASER, Hydroxyapatite and Iron oxide Nano Particles on Human Dental Enamel and Streptococcus Mutans (In Vitro study
Abstract Lasers have been tested with positive findings for the suppression of incipient caries, and many theories have been offered for this phenomenon. Nevertheless, early caries lesion prevention and biomimetic treatment are still difficulties despite massive efforts to promote dental hygiene. Nanoparticles’ exceptional qualities make them a promising biomaterial for a variety of medical and dental uses. There are a lot of exciting and promising uses for nanotechnology in the field of tissue repair and replacement, especially in dental mineralized tissues, thanks to the growing interest in this area. This research aimed to examine how certain nanoparticles and CO2 laser radiation affected the microhardness of enamel. In order to conduct the microhardness test, 80 first premolars from the maxilla were randomly split into eight groups, one control group and seven study groups, each containing ten teeth. Each tooth’s buccal (cheeky) side was standardized to have a circular window placed there, measuring 6 mm in diameter. The exposure period was 5 seconds in continuous wave (CW) mode, and the laser power was calculated to be 0.85 W using a unique equation. The concentration of the hydroxyapatite nanoparticles solution employed was 10%, whereas the concentration of the iron oxide nanoparticles solution was 12.5%. In this study, we evaluated the effects of certain agents on the microhardness of enamel before and after inducing a caries lesion by pH cycling techniques. Hardness variation was determined for each sample using a tailored equation. After demineralization, enamel microhardness values were found to be significantly lower across the board compared to healthy teeth’ microhardness values. This was the case across all groups. After treatment with certain agents, there was a marked increase in enamel microhardness values for all groups, with a statistically highly significant difference (p<0.001). The groups treated with laser followed by hydroxyl apatite nanoparticles (HANPs) and those treated with laser followed by iron oxide nanoparticles (IONPs) saw the greatest increases in their microhardness values. Treatment of teeth samples with laser followed by iron oxide nanoparticles (IONPs) induced the greatest change in enamel microhardness, while treatment of teeth samples with IONPs resulted in the lowest change in enamel microhardness compared to all of the other agents. As a potential preventative intervention against dental cavities, enamel treatment with CO2 laser, hydroxyapatite, and iron oxide nanoparticles might be examined. Doi link:https://doi.org/10.26655/JMCHEMSCI.2023.7.2
Sensitivity of Streptococcus mutans to Selected Nanoparticles (in Vitro Study) of research
Background: Nanoparticles are clusters of atoms in a size range from (1-100) nm. Nano dentistry creates amazing useful structures from individual atoms or molecules (nanoparticles), which provides a new alternative and a possibly superior strategy in prevention and treatment of dental caries through management of dental plaque biofilms. The aim of the study was to test the sensitivity of Streptococcus mutans to different concentrations of hydroxyapatite and iron oxide nanoparticles suspension solutions, in comparison to chlorhexidine, and de-ionized water, in vitro. Materials and methods: Agar well technique was applied to test the sensitivity of Streptococcus mutans to different concentrations of hydroxyapatite and iron oxide nanoparticles compared with chlorhexidine 0.2% as a control positive and de-ionized water as control negative. Zone of inhibitions which is clear zone of no growth of the bacteria were measured across the diameter of each well, no zone indicated a complete resistance of bacteria to the agents. Results: Values of mean of inhibition zone for all concentrations of hydroxyapatite nanoparticles were zero. While for iron oxide nanoparticles, they were zero until reaching the last three concentrations, in which there was a respective increase with a highly significant difference between groups (p>0.01). When making multiple comparisons of the inhibition zones of iron oxide nanoparticles between groups, findings showed that the inhibition zones of 17%, 20% and 22.5% of iron oxide nanoparticles were more than all other concentrations that had no inhibition zones with a significant difference (p>0.05). There was a highly significant difference between each concentration of hydroxyapatite and iron oxide nanoparticles with chlorhexidine and de-ionized water (p>0.01). Conclusion: Streptococcus mutans were not sensitive to hydroxyapatite nanoparticles, as there was a complete resistance for the agent. While for iron oxide nanoparticles, Streptococcus mutans were sensitive to 17.5%, 20% and 22.5% and sensitivity increased with the increase in concentration with a statistically highly significant difference and this indicates an antibacterial activity of this material. Keywords: Hydroxyapatite nanoparticles, Iron oxide nanoparticles, streptococcus mutans, Inhibition zone. Doi link: https://doi.org/10.12816/0046315https://doi.org/10.12816/0046315