adam, Author at IAOMT Library

Opinion on the Safety of Dental Amalgam and Alternative Dental Restoration Materials for Patients and Users.

The SCENIHR concludes that current evidence does not preclude the use of either amalgam or alternative materials in dental restorative treatment. However, the choice of material should be based on patient characteristics such as primary or permanent teeth, pregnancy, the presence of allergies to mercury or other components of restorative materials, and the presence of impaired renal clearance…..The SCENIHR recognises that there is a need for further research, particularly relating to (i) evaluation of the potential neurotoxicity of mercury from dental amalgam and the effect of genetic polymorphisms on mercury toxicity and (ii) to expand knowledge of the toxicity profile of alternative dental restorative materials. Furthermore, there is a need for the development of new alternative materials with a high degree of biocompatibility.

By Scientific Committee on Emerging and Newly Identified Health Risks.|2018-07-30T22:03:36+00:00January 1st, 2015|Mercury|

The microbiome and disease: reviewing the links between the oral microbiome, aging, and Alzheimer’s disease.

This review, gathered from diverse sources, shows how our microbiome influences health and ultimately how well we age. Evidence linking oral bacteria to Alzheimer’s disease (AD) is discussed in the context of aging, drawing together data from epidemiological, experimental, genetic, and environmental studies. Immunosenescence results in increased bacterial load as cell-mediated and humoral immune responses wane. The innate immune system gradually takes over; contributing to the rise in circulating proinflammatory cytokines such as TNFα. Maintaining the integrity of the blood-brain barrier (BBB) against a backdrop of increasing bacterial load is important. Aging may favor the proliferation of anaerobes in the mouth eliciting a robust TNFα response from the oral epithelium. Prolonged exposure to high levels of circulating TNFα compromises the integrity of the BBB. Sensitive techniques now detect the “asymptomatic” presence of bacteria in areas previously thought to be sterile, providing new insights into the wider distribution of components of the microbiome. These “immune-tolerated” bacteria may slowly multiply elsewhere until they elicit a chronic inflammatory response; some are now considered causal in instances of atherosclerosis and back pain. Inflammatory processes have long been associated with AD. We propose for a subset of AD patients, aging favors the overgrowth of oral anaerobes established earlier in life provoking a pro-inflammatory innate response that weakens the BBB allowing bacteria to spread and quietly influence the pathogenesis of AD. Finally, we suggest that human polymorphisms considered alongside components of the microbiome may provide new avenues of research for the prevention and treatment of disease.

By Shoemark DK, Allen SJ.|2019-05-30T21:38:24+00:00January 1st, 2015|Other|

Modifying effect of COMT gene polymorphism and a predictive role for proteomics analysis in children’s intelligence in endemic fluorosis area in Tianjin, China.

Cumulative fluoride exposure has adverse influences on children’s intelligence quotient (IQ). In addition, catechol-O-methyltransferase (COMT) gene Val158Met polymorphism (rs4680) is associated with cognitive performance. This study aimed to evaluate the associations of COMT polymorphism and alterations of protein profiles with children’s intelligence in endemic fluorosis area. We recruited 180 schoolchildren (10-12 years old) from high fluoride exposure (1.40 mg/l) and control areas (0.63 mg/l) in Tianjin City, China. The children’s IQ, fluoride contents in drinking water (W-F), serum (S-F), and urine (U-F); serum thyroid hormone levels, COMT Val158Met polymorphism, and plasma proteomic profiling were determined. Significant high levels of W-F, S-F, U-F, along with poor IQ scores were observed in the high fluoride exposure group compared with those in control (all P < 0.05). S-F and U-F were inversely related with IQ (r(s) = -0.47, P < 0.01; r(s) = -0.45, P = 0.002). Importantly, higher fluoride exposure was associated with steeper cognitive decline among children with the reference allele Val compared with those homozygous or heterozygous for the variant allele Met (95% CI, -16.80 to 2.55; P interaction < 0.01). Additionally, 5 up-regulated protein spots related to cell immunity and metabolism were detected in children with high fluoride exposure compared with the control. In conclusion, fluoride exposure was adversely associated with children’s intelligence, whereas the COMT polymorphism may increase the susceptibility to the deficits in IQ due to fluoride exposure. Moreover, the proteomic analysis can provide certain basis for identifying the early biological markers of fluorosis among children.

By Zhang S, Zhang X, Liu H, Qu W, Guan Z, Zeng Q, Jiang C, Gao H, Zhang C, Lei R, Xia T.|2019-01-06T21:20:41+00:00January 1st, 2015|Fluoride|

Galvanic corrosion of and ion release from various orthodontic brackets and wires in a fluoride-containing mouthwash.

BACKGROUND AND AIMS:
This study compared the galvanic corrosion of orthodontic wires and brackets from various manufacturers following exposure to a fluoride mouthwash.

MATERIALS AND METHODS:
This study was conducted on 24 lower central incisor 0.022″ Roth brackets of four different commercially available brands (Dentaurum, American Orthodontics, ORJ, Shinye). These brackets along with stainless steel (SS) or nickel-titanium (NiTi) orthodontic wires (0.016″, round) were immersed in Oral-B mouthwash containing 0.05% sodium fluoride for 28 days. The electric potential (EP) difference of each bracket-wire couple was measured with a Saturated Calomel Reference Electrode (Ag/AgCl saturated with KCl) via a voltmeter. The ions released in the electrolyte weremeasured with an atomic absorption spectrometer. All the specimens were assessed under a stereomicroscope and specimens with corrosion were analyzed with scanning electron microscopy (SEM). Data were analyzed using ANOVA.

RESULTS:
The copper ions released from specimens with NiTi wire were greater than those of samples containing SS wire. ORJ brackets released more Cu ions than other samples. The Ni ions released from Shinye brackets were significantly more than those of other specimens (P < 0.05). Corrosion rate of brackets coupled with NiTi wires was higher than that of brackets coupled with SS wires. Light and electron microscopic observations showed greater corrosion of ORJ brackets.

CONCLUSION:
In fluoride mouthwash, Shinye and ORJ brackets exhibited greater corrosion than Dentaurum and American Orthodontics brackets. Stainless steel brackets used with NiTi wires showed greater corrosion and thus caution is recommended when using them.

By Tahmasbi S, Ghorbani M, Masudrad M.|2018-08-02T21:19:06+00:00January 1st, 2015|Fluoride|

Peripheral neuropathic facial/trigeminal pain and RANTES/CCL5 in jawbone cavitation.

INTRODUCTION:

In this study, we elucidate the possible causative role of chronic subclinical inflammation in jawbone of patients with atypical facial pain (AFP) and trigeminal neuralgia (TRN) in the local overexpression of the chemokine regulated on activation and normal T-cell expressed and secreted (RANTES/C-C motif ligand 5 CCL5). Neurons contain opioid receptors that transmit antipain reactions in the peripheral and central nervous system. Proinflammatory chemokines like RANTES/CCL5 desensitize μ-opioid receptors in the periphery sensory neurons and it has been suggested that RANTES modifies the nociceptive reaction.

MATERIALS AND METHODS:

In 15 patients with AFP/TRN, we examined fatty degenerated jawbone (FDOJ) samples for the expression of seven cytokines by multiplex analysis and compared these results with healthy jawbones.

RESULTS:

Each of these medullary jawbone samples exhibited RANTES as the only highly overexpressed cytokine. The FDOJ cohort with AFP/TRN showed a mean 30-fold overexpression of RANTES compared to healthy jawbones.

CONCLUSIONS:

To the best of our knowledge, no other research has identified RANTES overexpression in silent inflamed jawbones as a possible cause for AFP/TRN. Thus, we hypothesize that the surgical clearing of FDOJ might diminish RANTES signaling pathways in neurons and contribute to resolving chronic neurological pain in AFP/TRN patients.

By Lechner J, von Baehr V.|2019-01-05T21:21:00+00:00January 1st, 2015|Periodontal Disease|

Allergic reactions to dental materials-a systematic review.

Our data included 71 relevant articles which included 60 case reports, 8 prospective studies and 3 retrospective studies. The source of these articles was Pub Med search done with the following terms: allergies to impression materials, sodium hypochlorite, Ledermix paste, zinc oxide eugenol, formaldehyde, Latex gloves, Methyl methacrylate, fissure sealant, composites, mercury, Nickel-chromium, Titanium, polishing paste and local anaesthesia. All the relevant articles and their references were analysed. The clinical manifestations of allergy to different dental materials based on different case reports were reviewed.

By Syed M, Chopra R, Sachdev V.|2018-08-02T21:00:29+00:00January 1st, 2015|Mercury, Other|

Fusobacterium nucleatum: a commensal-turned pathogen.

Fusobacterium nucleatum is an anaerobic oral commensal and a periodontal pathogen associated with a wide spectrum of human diseases. This article reviews its implication in adverse pregnancy outcomes (chorioamnionitis, preterm birth, stillbirth, neonatal sepsis, preeclampsia), GI disorders (colorectal cancer, inflammatory bowel disease, appendicitis), cardiovascular disease, rheumatoid arthritis, respiratory tract infections, Lemierre’s syndrome and Alzheimer’s disease. The virulence mechanisms involved in the diseases are discussed, with emphasis on its colonization, systemic dissemination, and induction of host inflammatory and tumorigenic responses. The FadA adhesin/invasin conserved in F. nucleatum is a key virulence factor and a potential diagnostic marker for F. nucleatum-associated diseases.

By Han YW.|2019-05-24T21:02:01+00:00January 1st, 2015|Other|

Effect of ionizing and non-ionizing radiation on amalgam, composite and zirconomer based restorations.

Dear Editor,
With great interest we read the article by Patel et al., entitled “An invitro Evaluation of Microleakage of Posterior Teeth Restored with Amalgam, Composite and Zirconomer–A Stereomicroscopic Study” [1] that is published in the July issue of the Journal of Clinical and Diagnostic Research (Vol-9(7): ZC65-ZC67, 2015). In this article, the authors performed an in vitro stereomicroscopic study to evaluate the microleakage of posterior teeth restored with amalgam, composite and zirconomer. In their study, cavities prepared on the occlusal surface, were restored with amalgam, composite and zirconomer.

By Mortazavi SM, Paknahad M, Mortazavi G.|2018-07-26T20:52:00+00:00January 1st, 2015|Mercury|

Hypersensitivity reactions to titanium: diagnosis and management.

Titanium is notable for its biocompatibility and is used as biologic implant material across surgical specialties, especially in metal-sensitive individuals. However, rare cases of titanium hypersensitivity reactions are reported in the literature. This article discusses the properties and biological behavior of titanium and provides a thorough review of the literature on reported cases, diagnostic techniques, and approach to management of titanium hypersensitivity.

By Wood MM, Warshaw EM.|2018-08-13T21:01:37+00:00January 1st, 2015|Other|

Identifying mercury heavy-metal poisoning masquerading as Dementia and Parkinson’s disease – recognizing neuropsychiatric manifestations and dietary contributors.

Assessing older adults presenting with cognitive decline, depression or other neuropsychiatric symptoms can be challenging because the underlying causes can be multifactorial. This article describes neuropsychiatric manifestations similar to those of Parkinson’s disease in an elderly man who upon examination was suspected of having an elevated blood mercury level through dietary exposure, a suspicion later confirmed by blood tests. We outline suggestions for comprehensive history taking to identify potential sources of environmental exposure and provide resources to help limit and prevent consumption of foods that can contain heavy metals.

By Chang F, Yeung KT, Chan G.|2018-07-19T20:25:45+00:00January 1st, 2015|Mercury|

adam

About Scientific Committee on Emerging and Newly Identified Health Risks.

INTRODUCTION:

MATERIALS AND METHODS:

RESULTS:

CONCLUSIONS: