adam

About Geier DA, Geier MR.

This author has not yet filled in any details.
So far Geier DA, Geier MR. has created 991 blog entries.

Dental amalgam fillings and mercury vapor safety limits in American adults.

Objective: For more than 150 years, dental amalgam fillings (50% metallic mercury (Hg0) by weight) have been used in American dentistry. The US Food and Drug Administration (FDA) acknowledged that amalgams release Hg vapor that may be harmful to certain patients. This study examined the impact of Hg vapor exposure from amalgams in American adults.

Methods: Amalgam-Hg vapor exposure among 158,274,824 weighted-adult Americans was examined in the 2015-2018 National Health and Nutrition Examination Survey (NHANES). Beta (β)-coefficients were calculated for the correlation between the number of amalgam surfaces and daily micrograms (μg) of urinary Hg and daily μg of Hg vapor exposure from amalgams per kilogram (Kg) bodyweight.

Results: About 91 million (57.8%) adults had ≥1 amalgam surface and about 67 million (42.2%) had no amalgams. A β-coefficient = 0.041 significantly correlated the number of amalgam surfaces to daily amounts of urinary Hg. Differences were observed for gender and racial groups. Daily Hg vapor doses from amalgams were in excess of the most restrictive California’s Environmental Protection Agency (EPA) safety limit for about 86 million (54.3%) adults and in excess of the least restrictive US EPA safety limit among about 16 million (10.4%) adults. The mean allowable number of amalgam surfaces ranged from 1.28 for adult females under the California’s EPA safety limit to 16.23 for adult males under the US EPA safety limit.

Conclusion: Given that American adults are receiving significant, ongoing exposure to Hg vapor from amalgams, careful evaluation of the need to reduce use of amalgams should be considered.

By |2024-08-22T22:43:01+00:00January 1st, 2024|Mercury|

Evaluation of Adjuvant Systems in Non-Surgical Peri-Implant Treatment: A Literature Review.

Can the use of lasers, ozone, probiotics, glycine and/or erythritol, and chlorhexidine in combination with non-surgical peri-implant treatment have additional beneficial effects on the clinical parameters? Objectives: The non-surgical treatment of peri-implant pathologies is based on mechanical debridement to eliminate bacterial biofilm and reduce tissue inflammation; some additional therapies have been studied to achieve more detailed clinical results. Materials and methods: A literature search for publications until January 2022 was conducted. The research question is formulated following the Problem, Intervention, Comparison/Control, and Outcome. Studies investigating adjunctive therapies were included. Results: In total, 29 articles were included. Most of the studies did not show any additional benefit of these therapies in the evaluation of bleeding on probing, probing pocket depth, or plaque index; among the proposed treatments, the use of laser was the one most studied in the literature, with the achievement of a reduction of bleeding and pocket depth. More studies would be needed to assess the benefit of other therapies. Conclusions: This review showed no significant improvements in the state of health in support of mechanical debridement therapy. However, the few benefits found would deserve to be considered in new clinical studies.

Antimicrobial Effect of Ozone Therapy in Deep Dentinal Carious Lesion: A Systematic Review.

Aim: This systematic review aimed to answer the following focused question: Is ozone therapy more effective in reducing microbial count as compared to conventional methods in deep dentinal carious lesion?

Objective: The purpose of this systematic review was to perform a review on the effectiveness of ozone therapy in reduction of microbial count in deep dentinal carious lesion. Study eligibility criteria, participants, and interventions: The inclusion criteria comprised studies that compared effect on microbial count in deep dentinal carious lesion after treatments with ozone and other disinfectants in primary or permanent teeth in randomized clinical trials.

Materials and methods: This review was conducted according to Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRIMSA) guidelines. The searched databases included Medline (via PubMed), Cochrane, and Google scholar. Articles published until 29 February 2020 without year restriction but only in English language were included.

Results: The search resulted in 359 published studies. After removal of duplicate studies and full-text analysis, seven studies were selected. Overall, the results demonstrated the promising effects of ozone therapy in reduction of microbial count as compared to other disinfectant.

Conclusions: Within the limitations of this review, it can be asserted that the ozone therapy is effective in reduction of microbial count in deep dentinal carious lesion.

Clinical significance: Ozone therapy can be a useful tool to reduce the microorganisms in deep dentinal carious lesion.

Low-Shrinkage Resin Matrices in Restorative Dentistry-Narrative Review.

Dimethacrylate-based resin composites restorations have become widely-used intraoral materials in daily dental practice. The increasing use of composites has greatly enhanced modern preventive and conservative dentistry. They have many superior features, especially esthetic properties, bondability, and elimination of mercury and galvanic currents. However, polymeric materials are highly susceptible to polymerization shrinkage and stresses that lead to microleakage, biofilm formation, secondary caries, and restoration loss. Several techniques have been investigated to minimize the side effects of these shrinkage stresses. The primary approach is through fabrications and modification of the resin matrices. Therefore, this review article focuses on the methods for testing the shrinkage, as well as formulations of resinous matrices available to reduce polymerization shrinkage and its associated stress. Furthermore, this article reviews recent cutting-edge developments on bioactive low-shrinkage-stress nanocomposites to effectively inhibit the growth and activities of cariogenic pathogens and enhance the remineralization process.

An In Vitro Study to Compare the Release of Fluoride from Glass Ionomer Cement (Fuji IX) and Zirconomer.

Mercury toxicity from amalgam dental fillings and their potential for creating problems in the environment and for human health have prompted the development of new restorative materials. The leading alternatives among these are glass ionomer cements. According to current understanding, restorative materials that slowly release fluoride exert a local cariostatic effect. For this purpose, glass ionomer cements have desirable properties in that they help prevent recurrence of caries by releasing fluoride over a long period. Thus, they function in accord with the major cariostatic mechanism of fluoride, which is believed to be its action to promote remineralization and to influence the morphology of teeth by reducing enamel solubility and by suppressing oral cariogenic bacteria. Although the minimum local concentration of fluoride release required to inhibit demineralization has not been determined, it is reported that the cariostatic ability of fluoride releasing restorative materials is significant. Zirconomer defines a new class of restorative that promises the strength and durability of amalgam with the protective benefits of glass ionomer while completely eliminating the hazards of mercury. The inclusion of specially micronized zirconia fillers in the glass component of zirconomer reinforces the structural integrity of the restoration and imparts superior mechanical properties for the restoration of load-bearing permanent teeth. Combination of outstanding strength, durability, and sustained fluoride protection deems it ideal for multiple applications. The aim of the present study was to determine the fluoride release from glass ionomer cements and compare it with new material zirconomer.

Antimicrobial effect of ozonated water on bacteria invading dentinal tubules.

Ozone is known to act as a strong antimicrobial agent against bacteria, fungi, and viruses. In the present study, we examined the effect of ozonated water against Enterococcus faecalis and Streptcoccus mutans infections in vitro in bovine dentin. After irrigation with ozonated water, the viability of E. faecalis and S. mutans invading dentinal tubules significantly decreased. Notably, when the specimen was irrigated with sonication, ozonated water had nearly the same antimicrobial activity as 2.5% sodium hypochlorite (NaOCl). We also compared the cytotoxicity against L-929 mouse fibroblasts between ozonated water and NaOCl. The metabolic activity of fibroblasts was high when the cells were treated with ozonated water, whereas that of fibroblasts significantly decreased when the cells were treated with 2.5% NaOCl. These results suggest that ozonated water application may be useful for endodontic therapy.

Microbial and molecular differences according to the location of head and neck cancers.

Background: Microbiome has been shown to substantially contribute to some cancers. However, the diagnostic implications of microbiome in head and neck squamous cell carcinoma (HNSCC) remain unknown.Methods: To identify the molecular difference in the microbiome of oral and non-oral HNSCC, primary data was downloaded from the Kraken-TCGA dataset. The molecular differences in the microbiome of oral and non-oral HNSCC were identified using the linear discriminant analysis effect size method. Results: In the study, the common microbiomes in oral and non-oral cancers were Fusobacterium, Leptotrichia, Selenomonas and Treponema and Clostridium and Pseudoalteromonas, respectively. We found unique microbial signatures that positively correlated with Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways in oral cancer and positively and negatively correlated KEGG pathways in non-oral cancer. In oral cancer, positively correlated genes were mostly found in prion diseases, Alzheimer disease, Parkinson disease, Salmonella infection, and Pathogenic Escherichia coli infection. In non-oral cancer, positively correlated genes showed Herpes simplex virus 1 infection and Spliceosome and negatively correlated genes showed results from PI3K-Akt signaling pathway, Focal adhesion, Regulation of actin cytoskeleton, ECM-receptor interaction and Dilated cardiomyopathy. Conclusions: These results could help in understanding the underlying biological mechanisms of the microbiome of oral and non-oral HNSCC. Microbiome-based oncology diagnostic tool warrants further exploration.

Clinical implications of growth hormone deficiency for oral health in children: a systematic review.

Dental age has been shown to be delayed in GHD patients by about 1 to 2 years. Moreover, the risk of dental caries in children with GHD decreases with increasing levels of vitamin D. Hence, further studies would be valuable for evaluating the risk of various oral health problems and to organize targeted dental care for this vulnerable group.

Go to Top