majid ahangari - Academia.edu (original) (raw)

Papers by majid ahangari

Research paper thumbnail of Prevalence of Oral Mucosal Lesions in Nursing Home Residents

Journal of Mazandaran University of Medical Sciences, 2016

Background and purpose: Many conditions and oral lesions are associated with aging that could hav... more Background and purpose: Many conditions and oral lesions are associated with aging that could have considerable impact on quality of life. This study investigated the prevalence of oral lesions in elderly in nursing homes. Materials and methods: A cross-sectional study was performed in 90 residents (over 60 years of age) in nursing homes in Sari and Babol, Iran, 2015. Data was recorded in a checklist and analyzed in SPSS ver.16 applying T-test, Chi-square and Fisher exact tests. Results: We studied 90 individuals including 26 males (28.9%) and 64 females (71.1%), mean age: 78.8 years. All elderly were found to have at least one lesion of the oral mucosa. The most common lesions were fissured tongue (55.6%), varicosity (46.7%), pigmentation (26.7%), candidiasis (25.6%) and sublingual varices (21.1%). Varicosity was more prevalent in men. 63.1% of the lesions were observed in tongue. The lesions in 60% of the people were due to wearing dentures (P< 0.05). There was no significant a...

Research paper thumbnail of Effects of Omega-6, Omega-9, Grape Seed Extract, and Chlorhexidine on Dentin Bond Strength

International Journal of Prosthodontics and Restorative Dentistry

Aim: Biodegradation of collagen matrix is one of the main factors in reducing the strength of den... more Aim: Biodegradation of collagen matrix is one of the main factors in reducing the strength of dentin-resin bond over time. The present study aimed to evaluate the effect of four natural agents on the prevention of collagen degradation which increases bond strength. Materials and methods: Twenty-five sound human premolars were selected. The middle one-third of the dentin was exposed by removing occlusal part of the crown. In order to increase the bond strength of the dentin-resin interface, four collagen cross-linking agents and matrix metalloproteinase (MMP) inhibitors were used in this study. The teeth were randomly divided into five groups according to the dentin treatment; control group (no treatment), pretreatment with chlorhexidine (CHX), grape seed extract (GSE), omega-9, and omega-6, respectively. Teeth were restored with Tetric N-Bond adhesive system and resin composite. After thermocycling, all the specimens were mounted on the slicing machine and then sectioned to produce a 1.0 mm 2 cross-sectional surface area that tested for tensile bond strength. Data were analyzed using one-way analysis of variance (ANOVA) and post hoc Tukey test. Results: The CHX pretreatment group (36.45 ± 1.85 MPa) had a significantly higher bond strength, compared to the other groups (p 0.05). Conclusion: The application of natural collagen cross-linkers and MMP inhibitors in this study (CHX 2%, GSE 6.5%, omega-9, and omega-6) were capable of significantly increasing resin-dentin bond strength.

Research paper thumbnail of Evaluation of the antibacterial and antibiofilm activity of probiotic bacteria against causative bacterial pathogens of dental caries

Journal of Current Biomedical Reports

The most important factor in tooth decay and periodontal disease is the attachment of oral bacter... more The most important factor in tooth decay and periodontal disease is the attachment of oral bacteria, especially streptococci, to different levels of the mouth and teeth. Therefore, by changing the microbial ecology in the mouth using probiotic producing bacteria, we can help prevent tooth decay and periodontal infections. This study aimed to evaluate the antibacterial and antibiofilm activities of probiotic producing Lactobacillus against several streptococci that cause tooth decay. Antimicrobial activity and minimal inhibitory concentration (MIC) of probiotic lactobacilli was determined by disk diffusion method and standard broth microdilution, respectively. Antibiofilm activity was assayed by a microtiter-plate screening method. The five isolates of Lactobacillus strains with probiotic properties include Lactobacillus plantarum, Lactobacillus rhamnosus, Lactobacillus reuteri, Lactobacillus fermentum, and Lactobacillus brevis were tested against Streptococcus mutans and Streptococcus sanguinis. Most of tested Lactobacillus strain at concentrations above 125 µg/mL showed antibacterial properties. Also, examination of the MICs showed that probiotic bacteria had greater effects on S. sanguinis. While, the tested probiotic bacteria did not show a significant antibiofilm effect. Our results suggest that lactobacilli with potential probiotic properties can be effective used for eliminating oral streptococcal colonization.

Research paper thumbnail of Prevalence of Oral Mucosal Lesions in Nursing Home Residents

Journal of Mazandaran University of Medical Sciences, 2016

Background and purpose: Many conditions and oral lesions are associated with aging that could hav... more Background and purpose: Many conditions and oral lesions are associated with aging that could have considerable impact on quality of life. This study investigated the prevalence of oral lesions in elderly in nursing homes. Materials and methods: A cross-sectional study was performed in 90 residents (over 60 years of age) in nursing homes in Sari and Babol, Iran, 2015. Data was recorded in a checklist and analyzed in SPSS ver.16 applying T-test, Chi-square and Fisher exact tests. Results: We studied 90 individuals including 26 males (28.9%) and 64 females (71.1%), mean age: 78.8 years. All elderly were found to have at least one lesion of the oral mucosa. The most common lesions were fissured tongue (55.6%), varicosity (46.7%), pigmentation (26.7%), candidiasis (25.6%) and sublingual varices (21.1%). Varicosity was more prevalent in men. 63.1% of the lesions were observed in tongue. The lesions in 60% of the people were due to wearing dentures (P< 0.05). There was no significant a...

Research paper thumbnail of Effects of Omega-6, Omega-9, Grape Seed Extract, and Chlorhexidine on Dentin Bond Strength

International Journal of Prosthodontics and Restorative Dentistry

Aim: Biodegradation of collagen matrix is one of the main factors in reducing the strength of den... more Aim: Biodegradation of collagen matrix is one of the main factors in reducing the strength of dentin-resin bond over time. The present study aimed to evaluate the effect of four natural agents on the prevention of collagen degradation which increases bond strength. Materials and methods: Twenty-five sound human premolars were selected. The middle one-third of the dentin was exposed by removing occlusal part of the crown. In order to increase the bond strength of the dentin-resin interface, four collagen cross-linking agents and matrix metalloproteinase (MMP) inhibitors were used in this study. The teeth were randomly divided into five groups according to the dentin treatment; control group (no treatment), pretreatment with chlorhexidine (CHX), grape seed extract (GSE), omega-9, and omega-6, respectively. Teeth were restored with Tetric N-Bond adhesive system and resin composite. After thermocycling, all the specimens were mounted on the slicing machine and then sectioned to produce a 1.0 mm 2 cross-sectional surface area that tested for tensile bond strength. Data were analyzed using one-way analysis of variance (ANOVA) and post hoc Tukey test. Results: The CHX pretreatment group (36.45 ± 1.85 MPa) had a significantly higher bond strength, compared to the other groups (p 0.05). Conclusion: The application of natural collagen cross-linkers and MMP inhibitors in this study (CHX 2%, GSE 6.5%, omega-9, and omega-6) were capable of significantly increasing resin-dentin bond strength.

Research paper thumbnail of Evaluation of the antibacterial and antibiofilm activity of probiotic bacteria against causative bacterial pathogens of dental caries

Journal of Current Biomedical Reports

The most important factor in tooth decay and periodontal disease is the attachment of oral bacter... more The most important factor in tooth decay and periodontal disease is the attachment of oral bacteria, especially streptococci, to different levels of the mouth and teeth. Therefore, by changing the microbial ecology in the mouth using probiotic producing bacteria, we can help prevent tooth decay and periodontal infections. This study aimed to evaluate the antibacterial and antibiofilm activities of probiotic producing Lactobacillus against several streptococci that cause tooth decay. Antimicrobial activity and minimal inhibitory concentration (MIC) of probiotic lactobacilli was determined by disk diffusion method and standard broth microdilution, respectively. Antibiofilm activity was assayed by a microtiter-plate screening method. The five isolates of Lactobacillus strains with probiotic properties include Lactobacillus plantarum, Lactobacillus rhamnosus, Lactobacillus reuteri, Lactobacillus fermentum, and Lactobacillus brevis were tested against Streptococcus mutans and Streptococcus sanguinis. Most of tested Lactobacillus strain at concentrations above 125 µg/mL showed antibacterial properties. Also, examination of the MICs showed that probiotic bacteria had greater effects on S. sanguinis. While, the tested probiotic bacteria did not show a significant antibiofilm effect. Our results suggest that lactobacilli with potential probiotic properties can be effective used for eliminating oral streptococcal colonization.