Comparison and Advanced Antimicrobial Strategies of Silver and Copper Nanodrug-Loaded Glass Ionomer Cement against Dental Caries Microbes.

Caries lesions during cement repairs are a severe issue, and developing a unique antimicrobial restorative biomaterial can help to reduce necrotic lesion recurrence. As a result, Thymus vulgaris extract was used to biosynthesize copper nanoparticles (TVE-CuNPs) exhibiting different characteristics (TVE). Along with TVE-CuNPs, commercial silver nanoparticles (AgNPs) and metronidazole were combined with glass ionomer cement (GIC) to test its antibacterial efficacy and compressive strength. FTIR, XRD, UV-Vis spectrophotometry, and TEM were applied to characterize the TVE-CuNPs. Additionally, AgNPs and TVE-CuNPs were also combined with metronidazole and GIC. The modified GIC samples were divided into six groups, where groups 1 and 2 included conventional GIC and GIC with 1.5% metromidazole, respectively; group 3 had GIC with 0.5% TVE-CuNPs, while group 4 had 0.5% TVE-CuNPs with metronidazole in 1.5%; group 5 had GIC with 0.5% AgNPs, and group 6 had 0.5% AgNPs with metronidazole at 1.5%. An antimicrobial test was performed against Staphylococcus aureus (S. aureus) and Streptococcus mutans (S. mutans) by the disc diffusion method and the modified direct contact test (MDCT). GIC groups 4 and 6 demonstrated a greater antimicrobial efficiency against the two tested strains than the other groups. In GIC groups 4 and 6, the combination of GIC with two antimicrobial agents, 1.5% metronidazole and 0.5% TVE-CuNPs or AgNPs, enhanced the antimicrobial efficiency when compared to that of the other groups with or without a single agent. GIC group specimens combined with nanosilver and nanocopper had similar mean compressive strengths when compared to the other GIC groups. Finally, the better antimicrobial efficacy of GIC boosted by metronidazole and the tested nanoparticles against the tested strains may be relevant for the future creation of more efficient and modified restorations to reduce dental caries lesions.

Antimicrobial Efficacy of Glass Ionomer Cement in Incorporation with Biogenic Zingiber officinale Capped Silver-Nanobiotic, Chlorhexidine Diacetate and Lyophilized Miswak.

In the present study, Zingiber officinale is used for the synthesis of Zingiber officinale capped silver nanoparticles (ZOE-AgNPs) and compares the antimicrobial efficacy and compressive strength of conventional glass ionomer cement (GIC) combined with ZOE-AgNPs, lyophilized miswak, and chlorhexidine diacetate (CHX) against oral microbes. Five groups of the disc-shaped GIC specimens were prepared. Group A: lyophilized miswak and GIC combination, Group B: ZOE-AgNPs and GIC combinations, Group C: CHX and GIC combination, Group D: ZOE-AgNPs + CHX + GIC; Group E: Conventional GIC. Results confirmed the successful formation of ZOE-AgNPs that was monitored by UV-Vis sharp absorption spectra at 415 nm. The X-ray diffractometer (XRD) and transmission electron microscope (TEM) results revealed the formation of ZOE-AgNPs with a mean size 10.5-14.12 nm. The peaks of the Fourier transform infrared spectroscopy (FTIR) were appearing the involvement of ZOE components onto the surface of ZOE-AgNPs which played as bioreducing, and stabilizing agents. At a 24-h, one-week and three-week intervals, Group D showed the significantly highest mean inhibitory zones compared to Group A, Group B, and Group C. At microbe-level comparison, Streptococcus mutans and Staphylococcus aureus were inhibited significantly by all the specimens tested except group E when compared to Candida albicans. Group D specimens showed slightly higher (45.8 ± 5.4) mean compressive strength in comparison with other groups. The combination of GIC with ZOE-AgNPs and chlorhexidine together enhanced its antimicrobial efficacy and compressive strength compared to GIC with ZOE-AgNPs or lyophilized miswak or chlorhexidine combination alone. The present study revealed that The combination of GIC with active components of ZOE-AgNPs and chlorhexidine paves the way to lead its effective nano-dental materials applications.

Association between obesity/overweight and dental caries in psychiatric patients.

BACKGROUND: Patients with psychiatric illness are more prone to develop obesity and dental caries due to general self-negligence associated with psychiatric illness and side effect of various medications used in psychiatry. OBJECTIVE: Assess the association between dental caries status and obesity among resident patients. DESIGN: Descriptive, cross-sectional. SETTING: Mental health hospital. PATIENTS AND METHODS: A sample of psychiatric in-patients was recruited. Dental caries detection was performed according to the World Health Organization criteria and body mass index (BMI) was measured. Relationships were assessed using multivariable logistic regression. MAIN OUTCOME MEASURES: Relationships between decayed, missing and filled teeth (DMFT) and obesity. SAMPLE SIZE: 223. RESULTS: The sample included 126 males and 97 female with a mean (SD) age of 42.3 (2.2) years. The prevalence of dental caries was 92.6%. The mean (SD) DMFT score was 5.2 (4.2). Twenty-seven percent were schizophrenic, 21.9% had mental retardation and 19.7% had bipolar mood disorder. The mean (SD) BMI was 27.7 (6.3) kg/m2. One hundred twenty-three (55.2%) of in-patients were classified as normal weight, 47 (21.1%) as overweight, and 45 (20.2%) as obese. The logistic regression model showed a strong association between caries and obesity/overweight (adjusted odds ratios=2.7; 95% CI=1.4 - 4.3, P<.001). CONCLUSION: The present study demonstrated a significant association between the frequency of caries and obesity/overweight among resident patients at a psychiatric hospital. LIMITATIONS: Since the data were cross-sectional, causal relationships cannot be established and the observed association could be due to other unexplored factors. CONFLICT OF INTEREST: None.

Resistance of resin-infiltrated enamel to surface changes in response to acidic challenge.

OBJECTIVE: To investigate the ability of resin infiltration to protect demineralized enamel against acidic challenge. MATERIALS AND METHODS: Forty-five extracted healthy premolars were selected for the study, each of which was sectioned vertically into 2 halves, giving 90 specimens. Specimens were then divided into three groups, where specimens of group A were not decalcified (control), while those of groups B and C were either subjected to decalcification only, or decalcification followed by Icon resin infiltration, respectively. Each group was further divided into three subgroups, according to the type of storage medium (water, Coca-Cola, or Redbull). Evaluation parameters included color difference and surface roughness. Scanning electron microscope was used to evaluate enamel surface topography. Statistical analysis was performed by ANOVA followed by least significant difference test. RESULTS: Although Coca-Cola caused the highest color change and surface roughness among the studied specimens, yet, the resin-infiltrated enamel was more resistant to surface changes than the nonresin infiltrated enamel, even under acid attack. CONCLUSION: Resin infiltration has the ability to provide and maintain protection to the demineralized enamel against acidic attack. CLINICAL SIGNIFICANCE: Resin infiltration may be considered as a promising solution to restore esthetic of demineralized enamel following orthodontic treatment and to protect it against acidic beverages.

Microleakage under orthodontic bands cemented with nano-hydroxyapatite-modified glass ionomer.

OBJECTIVES: To estimate the in vivo effect of nano-hydroxyapatite (HA) modification of banding glass-ionomer cement on microleakage under orthodontic bands. MATERIALS AND METHODS: Eighty noncarious premolars scheduled for extraction in 20 orthodontic patients were randomly divided into four groups. Grouping was based on the ratio of nano-HA (0%, 5%, 10%, 15% by weight) added to the luting glass-ionomer cement (GIC) Ketac-Cem, which was used for cementation of prefabricated micro-etched orthodontic bands. Dye penetration method was used for microleakage evaluation at the cement-band and cement-enamel interfaces. Statistical evaluation was performed with a Kruskal-Wallis test and a Mann-Whitney U-test, and a Bonferroni-adjusted significance level was calculated. RESULTS: Bands cemented with conventional GIC showed the highest microleakage scores in comparison to those cemented with nano-HA-modified GIC. No significant difference was found between teeth banded with 10% and 15% modified GIC. CONCLUSIONS: Modification of the banding GIC with 15% nano-HA revealed a positive effect on reducing microleakage around orthodontic bands.

In vivo effects of two acidic soft drinks on shear bond strength of metal orthodontic brackets with and without resin infiltration treatment.

OBJECTIVES: To evaluate the in vivo effects of two acidic soft drinks (Coca-Cola and Sprite) on the shear bond strength of metal orthodontic brackets with and without resin infiltration treatment. In addition, the enamel surface was evaluated, after debonding, using a scanning electron microscope. MATERIALS AND METHODS: Sixty noncarious maxillary premolars, scheduled for extraction in 30 orthodontic patients, were used. Patients were randomly divided into two groups according to the soft drink tested (Coca-Cola or Sprite). In each group, application of resin infiltration (Icon. DMG, Hamburg, Germany) was done on one side only before bonding of brackets. Patients were told to rinse their mouth with their respective soft drink at room temperature for 5 minutes, three times a day for 3 months. Shear bond strength was tested with a universal testing machine. After shearing test, a scanning electron microscope was used to evaluate enamel erosion. Statistical analysis was performed by twoway analysis of variance followed by the least significant difference test. RESULTS: The Coca-Cola group without resin infiltration showed the lowest resistance to shearing forces. Scanning electron micrographs of both groups after resin application showed a significant improvement compared with results without resin use, as the enamel appeared smoother and less erosive. CONCLUSION: Pretreatment with the infiltrating resin has proved to result in a significant improvement in shear bond strength, regardless of the type of soft drink consumed.

Alkali and heat treatment of titanium implant material for bioactivity.

PURPOSE: This study was conducted to evaluate alkali- and heat-treated titanium implant material. MATERIALS AND METHODS: Ninety-eight square plates of commercially pure titanium were divided into three groups. Group 1 plates were left untreated, and groups 2 and 3 were subjected to anodization and alkali treatment for 24 and 48 hours, respectively. Treated specimens were then subdivided into three equal subgroups (a, b, and c), which were heat treated for 1 hour at temperatures of 500°C, 700°C, and 800°C, respectively. Changes in the crystalline structure were analyzed using x-ray diffractometry. Surface roughness was measured using a surface roughness tester. Selected specimens were immersed in a specially prepared simulated body fluid for 10 days. Calcium and phosphorous deposition on the specimens was detected using energy dispersive x-ray analysis. RESULTS: Increasing the alkali treatment period and heat treatment temperature positively affected surface roughness and formation of a bioactive sodium titanium oxide (sodium titanate) layer on the titanium surface, especially after heat treatment at 800°C. There was a significantly higher calcium deposition on specimens of group 3 in comparison with those of groups 1 and 2. The results of pH and ion concentration changes of the used simulated body fluid confirmed the results of energy dispersive x-ray analysis. CONCLUSION: Alkali and heat treatment of titanium implant materials created better treatment conditions for obtaining a bioactive implant material.