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In light of the Minamata Convention on Mercury and efforts to phase down dental amalgam use, tracking dental amalgam proportions across US Food and Drug Administration (FDA)–identified at-risk populations is of interest to optimize material selection aligned with patient needs. A retrospective observational study of Epic's Cosmos electronic health records data set was conducted to calculate the rates of dental amalgam restorations from 2017 through 2023 and stratified using the social vulnerability index (quartile 4 indicates the highest social vulnerability and quartile 1 indicates the lowest) and payer type (Medicare, Medicaid, self-pay, miscellaneous or other). The authors included the following FDA-identified at-risk populations: pregnant people, children younger than 6 years, people with preexisting neurologic conditions, and people with impaired kidney function (n = 1,897,976). The overall rate of dental amalgam restoration placements in the general population declined from 21.8% in 2017 to 4.1% in 2023. Dental amalgam restoration trends, according to social vulnerability index quartile and payer type, decreased consistently across all 4 evaluated populations. Of all the social vulnerability index quartiles, quartile 4, representing the most socially vulnerable group, had the smallest decrease in dental amalgam placement rates among the FDA-identified populations examined. The study results showed a decreasing trend in dental amalgam restorations from 2017 through 2023 among FDA-identified populations, consistent with the Minamata Convention on Mercury directive for a phasedown in dental amalgam use. Notwithstanding improvements, lingering disparities persist among the most vulnerable population. Even within the groups identified as most vulnerable to harm, more targeted interventions and strategies are required to improve treatment among the most socially vulnerable. [ABSTRACT FROM AUTHOR]

Introduction: Understanding the reasons for retreatment of dental restorations is crucial to preventing potential tooth failure. Due to limited information on retreatment causes in our region, this study aims to compare the factors leading to the failure of posterior amalgam and composite restorations. Materials & Methods: This cross-sectional, observational study was conducted on patients referred to the restorative department of Ilam Faculty of Dentistry and private clinics who required retreatment of existing posterior restorations. Failure criteria for posterior restorations were evaluated based on established reference guidelines. Results: The study found that secondary caries had an odds ratio (OR) of 3.08 (95% CI: 2.85 - 3.29; p < 0.001), indicating a strong association with restoration failure. Additionally, restoration fractures were significantly correlated with retreatment, with an adjusted OR of 2.50 (95% CI: 2.46-2.86; p < 0.001). Conclusion: Secondary caries emerged as the most common reason for retreatment, regardless of whether composite or amalgam materials were used. Restoration fractures also significantly contributed to the need for retreatment. Therefore, it is essential to consider factors such as restoration material, classification, and the number of restoration levels to reduce the likelihood of retreatment. [ABSTRACT FROM AUTHOR]

Abstract Background The use of artificial intelligence in the field of health sciences is becoming widespread. It is known that patients benefit from artificial intelligence applications on various health issues, especially after the pandemic period. One of the most important issues in this regard is the accuracy of the information provided by artificial intelligence applications. Objective The purpose of this study was to the frequently asked questions about dental amalgam, as determined by the United States Food and Drug Administration (FDA), which is one of these information resources, to Chat Generative Pre-trained Transformer version 4 (ChatGPT-4) and to compare the content of the answers given by the application with the answers of the FDA. Methods The questions were directed to ChatGPT-4 on May 8th and May 16th, 2023, and the responses were recorded and compared at the word and meaning levels using ChatGPT. The answers from the FDA webpage were also recorded. The responses were compared for content similarity in “Main Idea”, “Quality Analysis”, “Common Ideas”, and “Inconsistent Ideas” between ChatGPT-4’s responses and FDA’s responses. Results ChatGPT-4 provided similar responses at one-week intervals. In comparison with FDA guidance, it provided answers with similar information content to frequently asked questions. However, although there were some similarities in the general aspects of the recommendation regarding amalgam removal in the question, the two texts are not the same, and they offered different perspectives on the replacement of fillings. Conclusions The findings of this study indicate that ChatGPT-4, an artificial intelligence based application, encompasses current and accurate information regarding dental amalgam and its removal, providing it to individuals seeking access to such information. Nevertheless, we believe that numerous studies are required to assess the validity and reliability of ChatGPT-4 across diverse subjects.

Background For more than 150 years, dental amalgam (DA) has been popular as a dental restorative material. Many organizations oppose its use due to perceived toxicity and environmental concerns. Hence, this study aimed to explore the continued use of DA from a South Indian dental practitioners’ perspective. Methods This cross-sectional study was conducted among fifty-two private and public dental practitioners of Udupi district in Southern India. A self‑administered questionnaire was distributed, that involved assessment of their preferences, continuation of use and concerns of using DA as a restorative material. The percentage contribution of each variable was calculated. Preferences for continuation of use of silver amalgam based upon the age, experience and mercury toxicity as a risk factor were analyzed using Students-t test and Fisher’s Exact Test test. Results Most dentists were satisfied (87%) with the results of the DA, found minimal failures (96%) and found DA more economical (89%). More than half (54%) of the participants reported that they would not continue the use of DA owing to mercury toxicity and environmental concerns. Dentists with higher age and longer clinical experience preferred continuation of DA. Conclusions Despite satisfaction with DA for its minimal failure, longevity and affordability, the authors found that most practitioners did not prefer its continued usage. This highlights their concerns over mercury toxicity and soft tissue lesions and accentuates their community social responsibility. There is also an urgent need to educate dentists on mercury hygiene, mercury waste management and disposal.

Background: The use of artificial intelligence in the field of health sciences is becoming widespread. It is known that patients benefit from artificial intelligence applications on various health issues, especially after the pandemic period. One of the most important issues in this regard is the accuracy of the information provided by artificial intelligence applications. Objective: The purpose of this study was to the frequently asked questions about dental amalgam, as determined by the United States Food and Drug Administration (FDA), which is one of these information resources, to Chat Generative Pre-trained Transformer version 4 (ChatGPT-4) and to compare the content of the answers given by the application with the answers of the FDA. Methods: The questions were directed to ChatGPT-4 on May 8th and May 16th, 2023, and the responses were recorded and compared at the word and meaning levels using ChatGPT. The answers from the FDA webpage were also recorded. The responses were compared for content similarity in "Main Idea", "Quality Analysis", "Common Ideas", and "Inconsistent Ideas" between ChatGPT-4's responses and FDA's responses. Results: ChatGPT-4 provided similar responses at one-week intervals. In comparison with FDA guidance, it provided answers with similar information content to frequently asked questions. However, although there were some similarities in the general aspects of the recommendation regarding amalgam removal in the question, the two texts are not the same, and they offered different perspectives on the replacement of fillings. Conclusions: The findings of this study indicate that ChatGPT-4, an artificial intelligence based application, encompasses current and accurate information regarding dental amalgam and its removal, providing it to individuals seeking access to such information. Nevertheless, we believe that numerous studies are required to assess the validity and reliability of ChatGPT-4 across diverse subjects. [ABSTRACT FROM AUTHOR]

Mercury, which is found in dental amalgams, is considered to be the most toxic non-radioactive element. However, the health policies of different countries have not reached a consensus on the use and safety of amalgam. This study aims to investigate the effect of amalgam restorations on mercury concentration in saliva, as well as the effect of restoration number, surface number, and chewing on this concentration. A total of 86 participants were included in this study (an equal number for the study and control groups). The number of amalgam restorations and their surfaces were recorded. While both unstimulated and stimulated saliva were collected from the study group, only unstimulated saliva was collected from the control group. The effect of chewing on mercury concentration was examined in the study group with unstimulated and stimulated saliva specimens using inductively coupled plasma mass spectrometry device. Mercury concentration in the unstimulated saliva was found to be higher in the study group compared to the control group (p= 0.000). As the number of amalgam restorations and the number of amalgam restoration surfaces increased, the mercury concentration in the saliva increased (p= 0.015 and p= 0.021, respectively). There was no statistically significant difference between mercury levels in the unstimulated saliva and the stimulated saliva (p=0.316). Chewing presented an insignificant difference in mercury concentration. Given this surprising result, the effect of chewing on mercury concentrations should be explored more extensively in future research. [ABSTRACT FROM AUTHOR]

Objectives: This study aimed to evaluate radiofrequency-induced heating of different amalgam restorations and dental implants during 1.5T magnetic resonance imaging (MRI). Materials and Methods: Standardized class I cavities (5 mm long, 3 mm wide, and 3 mm deep) were prepared on the occlusal surface of 45 extracted human third molars. The samples were restored by three different types of amalgam including Cinalux amalgam (non-gamma-2, spherical), GS-80 (non-gamma-2, admix), and GK-110 amalgam (non-gamma-2, admix in silver). As a separate intervention group (G4), five titanium mini drive-lock implants with 2mm diameter and 10mm length were also selected and mounted to the base of the Eppendorf tube with 3mm of the implants extending above the mounting putty. The box containing the specimens was placed parallel to the long axis of the standard head and neck coil of the MRI device (64MHz radio-frequency energy with 25kW amplifier, 1.5T). Temperature fluctuations of the metallic materials in each group were monitored during MRI scans using a calibrated thermometer. One-way ANOVA was used to compare temperature changes among the amalgam groups (P<0.05). Results: Temperature elevations ranged from 0.21°C to 0.70°C in amalgam restorations and from 0.35 to 0.47°C in dental implants. The temperature changes among the three amalgam agents were not statistically significant. Conclusion: According to our findings, the radiofrequency-induced heating of amalgam restorations and dental implants during MRI examination can be considered within acceptable ranges. Therefore, amalgam restorations and dental implants can be categorized as "MR safe" in terms of radiofrequency-induced heating during 1.5 T MRI. [ABSTRACT FROM AUTHOR]

Objectives: Teeth bleaching is an accepted and modern treatment in cosmetic dentistry. Bleaching agents may affect amalgam restorations and increase mercury release; therefore, patients are at increased risk of mercury exposure in the body. The aim of this study was to investigate the effect of polishing and universal bonding application on mercury release from aged amalgams exposed to bleaching. Materials and Methods: In this in-vitro experimental study, 64 dental amalgam specimens with dimensions of 3x5x10 were prepared and divided into two experimental and control groups. Each group was further divided into 4 subgroups and received one of the following treatments: no intervention, surface bonding, polishing, or polishing and surface bonding. Subsequently, the samples were immersed in bleaching agent containing 7% hydrogen peroxide and the amount of mercury released after 96h was measured. The results were analyzed by two-way ANOVA and Tukey post hoc tests (α≤0.05). Results: The results showed that the type of solution (P<0.05) and surface treatment (P<0.001) significantly affected the level of mercury release. However, there was no significant interaction between surface treatment methods in the bleaching group and those in the phosphate buffer group (P=0.621). Conclusion: Bleaching agents were found to enhance mercury release from dental amalgam. The application of polishing and universal bonding on amalgam surfaces exhibited significant effects on the reduction of the mercury release. [ABSTRACT FROM AUTHOR]

Background: Since the introduction of amalgam for tooth fillings, there have been concerns that mercury toxicity could pose unacceptable health risks. Rasa shastra is an ancient medical discipline that focuses on the utilization of metals and minerals for the treatment of diseases. Nevertheless, these minerals cannot be directly administered to the human body in their natural state due to their potential adverse effects. Hence, for medicinal purposes, these metals and minerals need to undergo purification (Shodhana) to eliminate impurities and modify their physical, chemical, and biological characteristics. Methodology: Human gingival fibroblasts (HGF) were exposed to commercially available mercury (CA-Hg) and ayurvedically purified mercury (AP-Hg) at concentrations of 6.25 μM, 12.5 μM, 25 μM and 50 μM. The unexposed HGF cultured in basal media was considered a control. All the samples were cultured for 24 hours and 48 hours, and the cytotoxicity was analyzed by MTT assay. Results: Cell viability between the control and experimental groups varied at 24 hours, however, the results were not statistically significant (p>0.05). At 48 hours, cell viability was higher in the AP-Hg group as compared to the CA-Hg group at the concentration of 6.25 μM, and the difference was statistically significant (p

Background For more than 150 years, dental amalgam (DA) has been popular as a dental restorative material. Many organizations oppose its use due to perceived toxicity and environmental concerns. Hence, this study aimed to explore the continued use of DA from a South Indian dental practitioners’ perspective. Methods This cross-sectional study was conducted among fifty-two private and public dental practitioners of Udupi district in Southern India. A self‑administered questionnaire was distributed, that involved assessment of their preferences, continuation of use and concerns of using DA as a restorative material. The percentage contribution of each variable was calculated. Preferences for continuation of use of silver amalgam based upon the age, experience and mercury toxicity as a risk factor were analyzed using Students-t test and Fisher’s Exact Test test. Results Most dentists were satisfied (87%) with the results of the DA, found minimal failures (96%) and found DA more economical (89%). More than half (54%) of the participants reported that they would not continue the use of DA owing to mercury toxicity and environmental concerns. Dentists with higher age and longer clinical experience preferred continuation of DA. Conclusions Despite satisfaction with DA for its minimal failure, longevity and affordability, the authors found that most practitioners did not prefer its continued usage. This highlights their concerns over mercury toxicity and soft tissue lesions and accentuates their community social responsibility. There is also an urgent need to educate dentists on mercury hygiene, mercury waste management and disposal.

Background: Since the introduction of amalgam for tooth fillings, there have been concerns that mercury toxicity could pose unacceptable health risks. Rasa shastra is an ancient medical discipline that focuses on the utilization of metals and minerals for the treatment of diseases. Nevertheless, these minerals cannot be directly administered to the human body in their natural state due to their potential adverse effects. Hence, for medicinal purposes, these metals and minerals need to undergo purification (Shodhana) to eliminate impurities and modify their physical, chemical, and biological characteristics. Methodology: Human gingival fibroblasts (HGF) were exposed to commercially available mercury (CAHg) and ayurvedically purified mercury (AP-Hg) at concentrations of 6.25 μM, 12.5 μM, 25 μM and 50 μM. The unexposed HGF cultured in basal media was considered a control. All the samples were cultured for 24 hours and 48 hours, and the cytotoxicity was analyzed by MTT assay. Results: Cell viability between the control and experimental groups varied at 24 hours, however, the results were not statistically significant (p>0.05). At 48 hours, cell viability was higher in the AP-Hg group as compared to the CA-Hg group at the concentration of 6.25 μM, and the difference was statistically significant (p<0.05). The cell proliferation assay results demonstrated a statistically significant difference in the mean optical density values (p<0.05) between CA-Hg and AP-Hg at 12.50 μM, 25 μM, and 50, μM concentrations observed at 24 hours. At 48 hours, a statistically significant difference in the mean OD values (p<0.05) between CA-Hg and AP-Hg at all four concentrations was observed. Conclusion: AP-Hg at a concentration of 6.25 μM demonstrated higher cell viability at 48 hours. Further, the cell proliferation rate was also higher for AP-Hg at all concentrations at 24 and 48 hours. These results indicated a less cytotoxic effect of AP-Hg than CA-Hg in HGF and hence could be employed for dental amalgam preparations. [ABSTRACT FROM AUTHOR]

Background For more than 150 years, dental amalgam (DA) has been popular as a dental restorative material. Many organizations oppose its use due to perceived toxicity and environmental concerns. Hence, this study aimed to explore the continued use of DA from a South Indian dental practitioners’ perspective. Methods This cross-sectional study was conducted among fifty-two private and public dental practitioners of Udupi district in Southern India. A self‑administered questionnaire was distributed, that involved assessment of their preferences, continuation of use and concerns of using DA as a restorative material. The percentage contribution of each variable was calculated. Preferences for continuation of use of silver amalgam based upon the age, experience and mercury toxicity as a risk factor were analyzed using Students-t test and Chi-square test. Results Most dentists were satisfied (87%) with the results of the DA, found minimal failures (96%) and found DA more economical (89%). More than half (54%) of the participants reported that they would not continue the use of DA owing to mercury toxicity and environmental concerns. Dentists with higher age and longer clinical experience preferred continuation of DA. Conclusions Despite satisfaction with DA for its minimal failure, longevity and affordability, the authors found that most practitioners did not prefer its continued usage. This highlights their concerns over mercury toxicity and soft tissue lesions and accentuates their community social responsibility. There is also an urgent need to educate dentists on mercury hygiene, mercury waste management and disposal.

Purpose: Dental amalgam contains mercury and is commonly used in dental restorations. The impact of MRI on mercury excretion from dental amalgam is not well understood across clinical field strengths, especially 7T. We investigated the effects of MRI exposure on mercury excretion using fresh, lab‐created dental amalgam restorations and in extracted teeth with old, pre‐existing restorations. Methods: Donated, unfilled human teeth (n = 120) were restored with amalgam before being stored in saline, artificial saliva, or a dry box prior to MRI scanning. The teeth were placed in individual tubes of fresh artificial saliva and scanned at 1.5T, 3T, or 7T or left unscanned as controls. Mercury concentrations were measured 24–30 h later. Donated teeth with pre‐existing restorations (n = 40) were stored in artificial saliva, scanned at 7T or left unscanned as controls, and mercury concentration tested. Results: For teeth extracted and restored in a laboratory, no significant difference was found (F = 2.42, P = 0.072) between mean mercury concentrations of unscanned teeth (13.72 μg/L) and teeth scanned at 1.5T (10.88 μg/L), 3T (12.65 μg/L), or 7T (8.88 μg/L). For teeth extracted with previously placed restorations, no significant difference (P = 0.288) was found between unscanned controls (4.28 μg/L) and teeth scanned at 7T (6.63 μg/L). Conclusion: MRI of dental amalgam does not significantly increase mercury excretion at 1.5T, 3T, or 7T compared to unscanned teeth. This holds true for controlled laboratory restorations as well as for those placed and lived with prior to extraction and scanning, demonstrating no added risk to the clinical patient or research subject. [ABSTRACT FROM AUTHOR]

Many contaminants can enter the environment via dentistry. Some of the materials including heavy metals may present some problems to the environment. Amalgam waste in dental clinics is the main source of mercury pollution in the environment. Apart from mercury, other amalgam constituents such as Ag, Sn, Co, Cu, and Zn in dental clinics’ wastewater have just been reported in a few previous kinds of literature. This study aimed to measure the concentrations of mercury, cobalt, zinc, copper, tin, silver, chromium, and nickel in the influent and effluent of dental units of some dental clinics. Samples were collected over 6-month period from 5 dental clinics and three samples were collected from each clinic at the end of the working day, within a week as the effluent sample. Metal concentration was also detected in the influent of the dental units and samples were analysed for metals using the atomic absorption spectrophotometry (AAS) technique for statistical analysis. Data were analysed with Wilcoxon and Kruskal – Wallis tests within SPSS 18 software. The concentration of all the metals in influent water was at the level of the national standard in all samples. In comparing influent and effluent values, the P-values for Hg, Zn, Cu, and Sn (0.001), Cu (0.003), Ag (0.028), Cr (0.007), and Ni (0.016) as shown significant differences between influent and effluent values for all the sample. Based on the obtained findings from the study, wastewater has an undesirable level in terms of heavy metals. Thus, dental clinic wastewater might be considered hazardous waste that should be properly treated before it discharges into the environment. [ABSTRACT FROM AUTHOR]

Objective: Health complaints attributed to dental amalgam fillings comprise both intraoral and general health complaints. There are data suggesting that patients with medically unexplained physical symptoms (MUPS) attributed to amalgam fillings show improvement in symptoms after removal of all amalgam fillings. However, data indicating changes of specific health complaints are limited. This study evaluated the changes of health complaints after removal of amalgam restorations in patients with health complaints attributed to dental amalgam fillings. Method: Patients with MUPS attributed to dental amalgam (Amalgam cohort) had all their amalgam fillings removed. The participants indicated an intensity of 11 local and 12 general health complaints on numeric rating scales before the treatment and at follow-up after 1 and 5 years. The comparison groups comprising a group of healthy individuals and a group of patients with MUPS without symptom attribution to dental amalgam did not have their amalgam restorations removed. Results: In the Amalgam cohort, mean symptom intensity was lower for all 23 health complaints at follow-up at 1 year compared to baseline. Statistically significant changes were observed for specific health complaints with effect sizes between 0.36 and 0.68. At the 5-year follow-up, the intensity of symptoms remained consistently lower compared to before the amalgam removal. In the comparison groups, no significant changes of intensity of symptoms of health complaints were observed. Conclusion: After removal of all amalgam restorations, both local and general health complaints were reduced. Since blinding of the treatment was not possible, specific and non-specific treatment effects cannot be separated.

Objectives: This study aimed to evaluate radiofrequency-induced heating of different amalgam restorations and dental implants during 1.5T magnetic resonance imaging (MRI). Materials and Methods: Standardized class I cavities (5 mm long, 3 mm wide, and 3 mm deep) were prepared on the occlusal surface of 45 extracted human third molars. The samples were restored by three different types of amalgam including Cinalux amalgam (non-gamma-2, spherical), GS-80 (non-gamma-2, admix), and GK-110 amalgam (non-gamma-2, admix in silver). As a separate intervention group (G4), five titanium mini drive-lock implants with 2mm diameter and 10mm length were also selected and mounted to the base of the Eppendorf tube with 3mm of the implants extending above the mounting putty. The box containing the specimens was placed parallel to the long axis of the standard head and neck coil of the MRI device (64MHz radio-frequency energy with 25kW amplifier, 1.5T). Temperature fluctuations of the metallic materials in each group were monitored during MRI scans using a calibrated thermometer. One-way ANOVA was used to compare temperature changes among the amalgam groups (P

Objectives: Teeth bleaching is an accepted and modern treatment in cosmetic dentistry. Bleaching agents may affect amalgam restorations and increase mercury release; therefore, patients are at increased risk of mercury exposure in the body. The aim of this study was to investigate the effect of polishing and universal bonding application on mercury release from aged amalgams exposed to bleaching. Materials and Methods: In this in-vitro experimental study, 64 dental amalgam specimens with dimensions of 3×5×10 were prepared and divided into two experimental and control groups. Each group was further divided into 4 subgroups and received one of the following treatments: no intervention, surface bonding, polishing, or polishing and surface bonding. Subsequently, the samples were immersed in bleaching agent containing 7% hydrogen peroxide and the amount of mercury released after 96h was measured. The results were analyzed by two-way ANOVA and Tukey post hoc tests (α≤0.05). Results: The results showed that the type of solution (P

Background For more than 150 years, dental amalgam (DA) has been popular as a dental restorative material. Many organizations oppose its use due to perceived toxicity and environmental concerns. Hence, this study aimed to explore the continued use of DA from a South Indian dental practitioners’ perspective. Methods This cross-sectional study was conducted among fifty-two private and public dental practitioners of Udupi district in Southern India. A self‑administered questionnaire was distributed, that involved assessment of their preferences, continuation of use and concerns of using DA as a restorative material. The percentage contribution of each variable was calculated. Preferences for continuation of use of silver amalgam based upon the age, experience and mercury toxicity as a risk factor were analyzed using Students-t test and Chi-square test. Results Most dentists were satisfied (87%) with the results of the DA, found minimal failures (96%) and found DA more economical (89%). More than half (54%) of the participants reported that they would not continue the use of DA owing to mercury toxicity and environmental concerns. Dentists with higher age and longer clinical experience preferred continuation of DA. Conclusions Despite satisfaction with DA for its minimal failure, longevity and affordability, the authors found that most practitioners did not prefer its continued usage. This highlights their concerns over mercury toxicity and soft tissue lesions and accentuates their community social responsibility. There is also an urgent need to educate dentists on mercury hygiene, mercury waste management and disposal.

Background The association between dental amalgam fillings and urine mercury concentrations was investigated in this study to assess the health risks associated with dental amalgams. Methods This cross-sectional study included 99 women in their 20s who visited the dental clinic in Daegu, Korea. The 99 participants were composed of 68 subjects who had dental amalgam fillings (exposure group) and 31 subjects who did not have dental amalgam fillings (nonexposure group). Oral examinations were conducted by a single dental hygienist, sociodemographic features were investigated as confounding variables, and urine mercury concentrations were measured using an automatic mercury analyzer. Results The mean±standard deviation of the urine mercury concentrations of the exposure and nonexposure groups were 1.50±1.78 μg/g creatinine and 0.53±0.63 μg/g creatinine, respectively. The exposure group showed significantly higher levels than the nonexposure group (p

Background: Dental caries stands as one of the most prevalent dental concerns, with early diagnosis being pivotal in clinical dentistry. Cone-beam computed tomography (CBCT) emerges as a widely utilized modality for dental caries identification, owing to its significant advantages. However, there remains a considerable knowledge gap regarding the efficacy of CBCT scans in detecting dental caries. In line with the as low as reasonably achievable principle, this study endeavors to evaluate the impact of amalgam fillings on the precision of occlusal caries detection in CBCT. Materials and Methods This in vitro study employed a set of 102 extracted human teeth samples. Among these, six molar teeth were used to create mesial-occlusal-distal amalgam restorations. The remaining teeth were placed in the dental sockets of a dry human skull to restore proximal contacts. CBCT images were obtained and examined by two observers, while histopathological examination was conducted using a stereomicroscope. Comparative analysis of CBCT images and histopathological data was performed using the McNemar test in SPSS software (α = 0.05). Results: The McNemar test results indicated that the nonrestoration group showed greater sensitivity and lower specificity in CBCT imaging than the amalgam-restored tooth group. Conclusion: The findings suggested that the CBCT technique did not demonstrate effectiveness in diagnosing dental caries around amalgam restorations.

Background For more than 150 years, dental amalgam (DA) has been popular as a dental restorative material. Yet, many organisations oppose its use due to perceived toxicity and environmental concerns. Hence, this study aimed to explore the continued use of DA from a South Indian dental practitioners’ perspective. Methods This cross-sectional study was conducted among fifty-two private and public dental practitioners of Udupi district in Southern India. A self‑administered questionnaire was distributed, that involved assessment of their preferences, continuation of use and concerns of using DA as a restorative material. Percentage contribution of each variable was calculated. Preferences for continuation of use of silver amalgam based upon the age, experience and mercury toxicity as a risk factor were analysed using Students-t test and Chi-square test. Results The majority of dentists were satisfied (87%) with the results of the DA, found minimal failures (96%) and found DA more economical (89%). More than half (54%) of the participants reported that they would not continue the use of DA owing to mercury toxicity and environmental concerns. Dentists with higher age and longer clinical experience preferred continuation of DA. Conclusions In spite of satisfaction with DA for its minimal failure, longevity and affordability, the authors found that a majority of practitioners did not prefer its continued usage. This highlights their concerns over mercury toxicity and soft tissue lesions and accentuates their community social responsibility. There is also an urgent need to educate dentists on mercury hygiene, mercury waste management and disposal.

Objective: To guide professionals about the criteria for replacing amalgam restorations and inform them about the new guidelines regarding the use/indication of this (amalgam) material after the Minamata Convention – COP-4. Material and Methods: The articles were selected from the databases (PubMed, Scielo, Bireme), and relevant articles on the subject between the years 2003-2021 were selected. Recently, social media have been flooded with dental treatments that aim to perform restorations only with composite resins or other types of esthetic material and completely replace all dental amalgam restorations, irrespective of their time in place, size, and functionality. Results: Although improperly, it has been noted that this information reaches patients, and they are led to believe in the inaccurate data that is passed on, such as, for example, (that amalgam leads to) permanent contamination by mercury, causing systemic problems and the loss of the tooth. Conclusion: The "phase down" of amalgam in research and teaching has previously been observed in several countries worldwide; however, its use is still necessary given particular circumstances, which, theoretically, make it a material with exact indication.

BACKGROUND: Dentists using dental amalgam are chronically exposed to low doses of elemental mercury. The complex toxico-kinetics of this systemic toxicant results in polymorphic and variable clinical phenotypes. In this context, adapted statistical methods are required to highlight potential adverse effects of occupational mercury exposure on dentists' health. OBJECTIVE: The present study aims to analyze the distribution of self-reported subjective symptoms, commonly associated with chronic mercury poisoning, according to occupational mercury exposure in a population of Moroccan liberal dentists. METHODS: In order to achieve the defined objectives, a three-step latent class regression was fitted. First a latent class analysis was performed to cluster the studied population according to their declared symptoms. Dentists were then classified in the defined latent classes based on their posterior probabilities. Finally, a logistic regression is fitted to identify predictors associated with the latent classes' membership. RESULTS: The final obtained model showed acceptable calibration and discrimination. Its interpretation revealed that the increase of the frequency of amalgam use was associated with significant higher odds of belonging to the high risk latent class. CONCLUSIONS: The present study represents an initial step towards the development of diagnosis model that predict clinical profiles according to occupational mercury exposure. [ABSTRACT FROM AUTHOR]

Introduction Recurrent caries can occur in different restorative materials. This is the significant factor in the failure and replacement of restorative materials. Early lesion detection is crucial to improve the chances of good treatment outcome and prevent significant hard tissue loss. The objectives of this study were to determine the prevalence of recurrent caries and it's association with different restorative materials in South Indian Coastal population. Materials and Methods A total of 560 restorations in 183 patients, who visited A B Shetty Memorial Institute of Dental Sciences, Deralakatte were examined clinically and radiographically for the presence of secondary caries. Patients in the age group of 18-60 years were included in the study. Results A total of 245 restorations were diagnosed with recurrent caries, which gives an overall prevalence of 47%. The percentage of recurrent caries was significantly higher with composite restorations and were seen in class II gingival margins. Conclusion Prevalence of secondary caries was higher with composite restorations, gingival margins of Class II restorations were more prone for secondary caries. Overall the prevalence of secondary caries in South Indian coastal population was high. Emphasis should be based on prevention, early diagnosis and management of SC. [ABSTRACT FROM AUTHOR]

Background/Aim. The cause of discolored gingiva (DG) is the presence of metal in the gingival tissue. DG is a relatively common case and is caused by the deposition of amalgam material in the gingival tissue during dental application or oral surgery. The aim of this study was to determine the significance of the presence of a cast post for the appearance of DG of abutment teeth (AT) in relation to the type of alloy used to make the fixed dental prosthesis (FDP). Methods. The study included 327 subjects with FDP. A total of 1,585 AT were examined. The subjects were classified into four groups depending on the type of alloy used to fabricate their FDPs (silver-palladium, gold, nickel-chromium alloy, or a combination of them). The presence of a cast post was confirmed by X-ray or by inspection of the dental chart. The study was conducted over the course of one year. Results. DG was observed in more than one-third (37.7%) of the subjects, of which 57.3% had a cast post. In the case of AT, discoloration occurred in 14.6%. Cast post was present in 92.7% of AT with DG. Conclusion. DG occurred in all groups of subjects regardless of the type of alloy from which the FDP was fabricated. The presence of a cast post is of great significance for the appearance of gray-bluish discoloration of the gingiva. [ABSTRACT FROM AUTHOR]

Abstract A multicenter, randomized controlled clinical trial evaluated the effectiveness of two treatments for deep caries lesions in permanent molars - selective caries removal (SCR) to soft dentin with restoration in a single visit, and stepwise excavation (SW) - regarding pulp vitality for a 5-year follow-up period. The present study aimed to determine the cost-effectiveness of these treatments. Treatments were conducted in two Brazilian cities (Brasília and Porto Alegre). At baseline, 299 permanent molars (233 patients) were treated and 229 teeth (174 patients) were evaluated after 5 years. The discounted cash flow method was adopted. The total cost of each treatment was calculated, and the failure cost (endodontic treatment + restoration) was added to the final cost, according to the 5-year failure rates of each therapy (20% for SCR and 44% for SW). A public health service unit composed of three dentists in 4-hour work shifts was used to calculate the monetary value of the treatments, assuming a total of 528 treatments/month. Considering the 229 teeth evaluated after 5 years (115 SCR and 114 SW), SCR provided savings of 43% (amalgam) and 41% (resin composite) per treatment, compared to SW. The SCR technique provides benefits for public finances (direct economy) and for public health services (increase in the number of treatments performed). Considering that maximizing profit and reducing costs are powerful motivating factors for adopting a certain treatment, this study provides data to better support the decision-making process, regarding the management of deep caries lesions in permanent molars.

Background: Diagnosis of dental caries using cone-beam computed tomography (CBCT) may be hindered due to several introduced and inherent artifacts. The aim of this study was to evaluate the effect of amalgam fillings on the accuracy of diagnosis of proximal caries in CBCT. Materials and Methods: In this in vitro study, 102 extracted human teeth (mandibular and maxillary molars and premolars) were used. Six molars were chosen for mesio-occluso-distal amalgam restorations. Before obtaining the CBCT images, the 96 remaining teeth were stabilized in dental sockets of six dry human skulls in a way that the proximal contacts re-established. Thereafter, six of the molar teeth were replaced by the amalgam-restored teeth and the second group of images was then obtained. All images were evaluated by two independent observers in the panorama view and the presence or absence of caries was recorded. For histopathologic investigations, the teeth were cut and assessed by an oral pathologist using a stereomicroscope. The McNemar test was used for comparison between CBCT assessments and histopathologic evaluations (P < 0.05 was considered statistically significant). In addition, the receiver operating characteristics curve was utilized to evaluate the diagnostic accuracy in different sections of imaging. Results: The result sensitivity and specificity of CBCT imaging in the first group of images before placement of the restored teeth were 0.96 and 0.36, respectively. In the second group of images after placement of the restored teeth, these values were 0.78 and 0.18, respectively. Moreover, statistical analysis showed that there is a good agreement in interproximal caries diagnosis between histopathologic and CBCT imaging findings without placement of amalgam restorations (P < 0.001). However, this agreement does not exist after amalgam restorations (P = 0.84). Conclusion: Diagnosis of proximal caries using CBCT is not an efficient method where there are amalgam restorations adjacent to the suspected teeth. [ABSTRACT FROM AUTHOR]

Objectives: The aim of the study was to assess the biocompatibility of modern composite and amalgam dental fillings. Material and Methods: The research was conducted on 150 healthy patients between the ages of 10 and 20 who had amalgam and composite fillings between 6 and 12 months. Under in vivo conditions, a swab of buccal cells near the fillings was taken, and the cytotoxic and genotoxic impact of composite and amalgam fillings on these cells was analyzed using the extended micronucleus test (cytomeassay). Results: The results showed statistically significant differences between the groups of subjects with amalgam and composite fillings and subjects without fillings for the following parameters: number of micronuclei (p=0.006), number of buds (p

This paper sets out the current position with respect to the replacement of dental amalgam as a restorative material. The environmental impact and the question of possible adverse effects of mercury on human health, including that of dental personnel, are reviewed. The literature has been surveyed using Pub Med with the following key words employed: dental amalgam; environmental; disposal; alternative materials. This identified a large number of papers, and more recent ones were selected for inclusion, particularly where they summarised the earlier literature. The findings of this process are that dental amalgam remains a popular and widely used material which, with appropriate hygiene measures, does not pose a threat to human health. However, environmental concerns with the mining, transport and technical uses of mercury led to the Minamata Convention in 2013, one consequence of which is that mining of mercury will cease from the year 2032. This means that dental amalgam will no longer be available for use. This article considers alternative materials. Results from the literature show that neither of the main possibilities, namely composite resins of glass-ionomer cements, compares with amalgam in terms of strength or durability. The impact of this on the dental profession is discussed briefly.

Introduction: Recently, a new category of dental bonding agents called universal adhesives has been introduced to the market, which are claimed to be able to create a strong bond between composite resins and teeth, metal surfaces and all types of ceramics alone and without the use of other primers. The aim of this study was to evaluate the performance of universal adhesives in the repair of amalgam restorations with composite resins in comparison with the conventional method. Material & Methods: In this experimental in vitro study, 80 amalgam blocks were prepared and after abrading the surface with an intraoral sandblaster and performing the aging process, the specimens were divided into 4 groups of 20 each, depending on how each surface was prepared by different bonding in the following order: Single Bond2 (S), Alloy Primer and Single Bond (AS), G-Premio Bond (G) and Alloy Primer and G-Premio Bond (AG). The composite blocks were then cured on the surface of the specimens. Finally, the specimens were tested for micro-shear bond strength (µSBS) using a micro-tensile tester and their cross-section was examined for fracture pattern under a stereomicroscope. Data were analyzed using Kruskal-Wallis, Man Whitney, and chi-square tests. A value of P

Background: Head and neck radiotherapy causes side effects such as stomatitis. In vitro studies demonstrated local dose enhancement due to backscatter radiation near metal restorations. The aim of this study was to analyze correlation between number of amalgam restorations with severity of oral mucositis in patients with head and neck radiotherapy. Method and materials: This cross-sectional study was accomplished on 80 patients under head and neck radiotherapy referred to Cancer Institute (Tehran, Iran) in 2014–2015. Severity of mucositis and pain were measured by three examinations according to WHO criteria and visual analogue scale. Descriptive statistics and Spearman's correlation coefficient test used to analyze the data by IBM SPSS statistics V22.0. Results: There was no significant correlation between the number of amalgam restorations and severity of mucositis and pain on second and third examinations. However, severity of mucositis and pain were found to be significantly correlated with radiation dose per session (p = 0.013, rs = 0.276), (p = 0.032, rs = 0.240) and total radiation dose (p < 0.001 rs = 0.393), (p < 0.001, rs = 0.445) on second and third examinations respectively. Conclusion: This study showed that number of dental amalgam restorations have no impact on aggravation of oral mucositis caused by head and neck radiotherapy. [ABSTRACT FROM AUTHOR]

A prospective cohort study on changes of health complaints after removal of amalgam restorations was carried out at the request of the Norwegian Directorate of Health. The aim was to provide and evaluate experimental treatment to patients with health complaints attributed to dental amalgam fillings. Patients (n = 32) with medically unexplained physical symptoms (MUPS), which were attributed to dental amalgam restorations had all their amalgam restorations removed and replaced with other dental restorative materials. Samples of blood were collected before and 1 year after removal of the fillings, and concentration of inorganic mercury (I-Hg), methylmercury (MeHg), silver (Ag) and selenium (Se) in serum was determined by inductively coupled plasma–sector field mass spectrometry. The comparison groups (one with MUPS but without attribution to amalgam [n = 28] and one group of healthy individuals [n = 19]) received no treatment. The participants responded to questionnaires at baseline and at follow-up after 1 and 5 years. Concentration of I-Hg and Ag in serum decreased significantly after removal of all amalgam restorations. Concentration of MeHg and Se in serum were not changed. Intensity of health complaints was significantly reduced after amalgam removal, but there were no statistically significant correlations between exposure indicators and health complaints. Removal of all amalgam restorations is followed by a decrease of concentration of I-Hg and Ag in serum. The results support the hypothesis that exposure to amalgam fillings causes an increase of the daily dose of both I-Hg and Ag. Even though intensity of health complaints decreased after removal of all amalgam restorations there was no clear evidence of a direct relationship between exposure and health complaints. Trial registration: The project is registered at Clinicaltrials.gov (NCT01682278). [ABSTRACT FROM AUTHOR]

Amalgam has been used for more than 150 years as a safe and reliable restorative material. The authors described the occurrence of amalgam and nonamalgam restorations in the United States in primary and permanent teeth across age groups and according to sociodemographic characteristics. The authors used clinical examination data from the National Health and Nutrition Examination Survey 2015-2018 for participants 2 years and older (n = 17,040). The authors estimated the prevalence and mean number of amalgam and nonamalgam restorations in primary and permanent teeth according to age groups (2-5 years, 6-11 years, 12-15 years, 16-19 years, 20-39 years, 40-59 years, 60-79 years, and ≥ 80 years), race and ethnicity, federal poverty guideline, education, and pregnancy status. The prevalence of amalgam restorations ranged from 4% through 69%. Overall, amalgam restorations were more prevalent in children and adolescents from racial and ethnic minority groups and families at lower poverty levels and with lower education. The mean number of teeth with nonamalgam restorations was higher than those with amalgam restorations in primary teeth of children aged 6 through 11 years, permanent teeth of those 12 through 15 years and 20 through 39 years, and women aged 20 through 49 years, regardless of pregnancy status. The mean number of amalgam restorations was higher than that for nonamalgam restorations in older age groups. Nonamalgam restorations were the most common in the primary teeth of children older than 5 years and in the permanent teeth of adults younger than 40 years. Amalgam restorations were more common in older adults. Amalgam and nonamalgam restorations were equally common in children younger than 5 years. The study findings suggest a shift from amalgam to alternative restorative materials in the United States. [ABSTRACT FROM AUTHOR]

In the context of evolving dental materials and techniques and a national agenda to phasedown use of dental amalgam, estimates of dental amalgam placement are necessary for monitoring purposes. Numbers of amalgam and composite posterior restorations from 2017 through 2019 were calculated using retrospective dental claims analysis of privately insured patients. Kruskal-Wallis and multilevel, multivariable negative binomial regression models were used to test for differences in rates of amalgam and composite restoration placement by age group, sex, urban or rural area, and percentage race and ethnicity area distribution. Statistical significance was set at 0.05, with Benjamini-Hochberg correction for false discovery rate. The rate of amalgam restorations declined over time from a mean of 6.29 per 100 patients in 2017 to 4.78 per 100 patients in 2019, whereas the composite restoration rate increased from 27.6 per 100 patients in 2017 to 28.8 per 100 in 2019. The mean number of amalgam restorations placed per person were lowest in females compared with males, in urban areas compared with rural areas, and in areas with more than 75% non-Hispanic White residents. Amalgam restoration placements in privately insured people in the United States declined from 2017 through 2019. Amalgam restoration placements may be unevenly distributed by location. Achieving further declines of dental amalgam use may require changes to insurance coverage, incentives, and provider training as well as augmented disease prevention and health promotion efforts. These efforts should focus particularly on groups with high caries risk or higher rates of amalgam placement. [ABSTRACT FROM AUTHOR]

Using a three-dimensional finite element analysis, this study aimed to evaluate the effect of different cements' thicknesses and Poisson's ratios on the stress distribution in enamel, dentin, restoration, and resin cement in a computer-aided design of a class II disto-occlusal cavity. Dental tomography was used to scan the maxillary first molar, creating a three-dimensional tooth model. A cavity was created with a 95 degree cavity edge angle. Resin cement with varying Poisson's ratios (V1: 0.35 and V2: 0.24) was used under the amalgam. The simulated groups' thicknesses ranged from 50 µm to 150 µm. A load of 600 N was applied to the chewing area. The finite element method was used to assess the stress distribution in the enamel, dentin, restorations, and resin cement. The stress in the restoration increased with the use of a 100 µm resin cement thickness and decreased with the use of a 150 µm resin cement thickness. For the V1 and V2 groups, the cement thickness with the maximum stress value for the enamel and dentin was 150 µm, while the cement thickness with the lowest stress value was 50 µm. The greatest stress values for V1 and V2 were obtained at a 150 µm cement thickness, while the lowest stress values were observed at a 100 µm cement thickness. Using resin cement with a low Poisson's ratio under amalgam may reduce stress on enamel and restorations. [ABSTRACT FROM AUTHOR]

Objective: To evaluate and compare bite force (BF) in permanent first molars restored with glass ionomer cement (GIC), composite and amalgam, and normal contralateral permanent first molars. Material and Methods: BF was recorded in decayed permanent first molars, which were filled with GIC (n=30), composite (n=30), and amalgam (n=30), and in healthy contralateral first molars (n=90) with Force Transducer Occlusal Force Meter and compared. Results: BF was significantly higher in normal teeth on the contralateral side compared to teeth restored with GIC and composite. However, in patients with amalgam restoration, though it was less compared to that on the contralateral side, it was not statistically significant (p>0.05). Conclusion: Restoring teeth with various filling materials may improve bite force. In the present study, it was found that the teeth restored with amalgam had higher bite forces in comparison to the other restorative materials used. However, it was not comparable to that observed in the normal tooth (control) on the contralateral side.

IntroductionThis paper set out to investigate the relationship between teaching and clinical practice of direct posterior restoration placement at tertiary dental institutions in South Africa.MethodsA cross-sectional study using a mixed methods approach was conducted, and all the South African dental schools were invited to participate. The quantitative phase of the study analyzed the Conservative Dentistry department's records of direct restorations at a single dental school. The number of amalgam and tooth-colored restorations placed by students in the fourth and fifth year of the program from 2004 to 2019 were compared. During the qualitative phase, semi-structured interviews were held with staff from the four dental schools involved with the teaching of direct posterior restorations.ResultsThe predominant direct posterior restoration placed in student clinics over a 15-year period at a South African dental school was tooth colored (75%). Teaching times do not correspond to a decrease in the placement of dental amalgam restorations for both one-surface and two-surface posterior restorations and a concomitant increase in the tooth-colored restorations.DiscussionAcademic staff involved in teaching identified that South Africa's ratification of the Minamata Convention has consequences for dental education and training. However, all schools reported that dental amalgam would continue to be taught in the absence of an appropriate alternative.

Introduction: This study aimed to evaluate the relationship between dental amalgam filling and cognition in older adults. Materials and Methods: A total of 169 patients aged 65 years and above were recruited from a geriatric outpatient clinic. Their socio-demographic and chronic disease data were recorded. All patients underwent oral examinations. Amalgam filling index scores were calculated for individuals with amalgam fillings. The participants were divided into a study group [amalgam (+)] and a control group [amalgam (-)] based on their amalgam-filling statuses. For sub-analysis, the amalgam-filled group was categorised according to high (≥4.191) and low (<4.191) mean index scores. Standardised mini-mental test, clock drawing test and Lawton-Brody instrumental activities of daily living scale were conducted for all patients. Results: About 46.2% (n=78) of participants were female, mean age was 69.6 ± 6.3 years and 53.7% (n=89) had amalgam fillings. There was no significant difference in the standardised mini-mental test, clock drawing test and Lawton-Brody instrumental activities of daily living scale scores between the study and control groups (all p>0.05), or in all test scores between participants with high and low amalgam scores in the group with amalgam fillings. Conclusions: This study showed that dental amalgam fillings were not associated with cognitive decline in older adults. [ABSTRACT FROM AUTHOR]

Different types of direct-placement dental materials are used for the restoration of structure, function and aesthetics of teeth. The aim of this research investigation is to determine, through a comparative cradle-to-gate life cycle assessment, the environmental impacts of three direct-placement dental restorative materials (DRMs) and their associated packaging. Three direct-placement dental materials; dental amalgam, resin-based composite (RBC) and glass polyalkenoate cements (GIC) are assessed using primary data from a manufacturer (SDI Limited, Australia). The functional unit consisted of 'one dental restoration' of each restorative system under investigation: 1.14 g of dental amalgam; 0.25 g of RBC (plus the adhesive = 0.10 g); and 0.54 g of GIC. The system boundary per restoration included the raw materials and their associated packaging materials for each DRM together with the processing steps for both the materials and packaging. The environmental impacts were assessed using an Egalitarian approach under the ReCiPe method using Umberto software and the Ecoinvent database. Nine different impact categories were used to compare the environmental performance of these materials. Dental amalgam had the highest impact across most of the categories, but RBC had the highest Global Warming Potential. The highest sources of the environmental impacts for each restorative material were: Amalgam, derived from material use; RBC, derived from energy use in processing material and packaging material; GIC, derived from material and energy use for packaging. Less intensive energy sources or more sustainable packaging materials can potentially reduce the impacts associated with RBC and GIC thus making them suitable alternatives to dental amalgam. [Display omitted] • The environmental impact of three dental restorative materials was assessed empirically. • Nine life-cycle impact assessment categories were investigated with the ReCiPe method. • Dental amalgam had the highest and glass ionomers the lowest impact across most categories. • Changes in energy mix and packaging materials can potentially reduce the impacts. [ABSTRACT FROM AUTHOR]

A multicenter, randomized controlled clinical trial evaluated the effectiveness of two treatments for deep caries lesions in permanent molars - selective caries removal (SCR) to soft dentin with restoration in a single visit, and stepwise excavation (SW) - regarding pulp vitality for a 5-year follow-up period. The present study aimed to determine the cost-effectiveness of these treatments. Treatments were conducted in two Brazilian cities (Brasília and Porto Alegre). At baseline, 299 permanent molars (233 patients) were treated and 229 teeth (174 patients) were evaluated after 5 years. The discounted cash flow method was adopted. The total cost of each treatment was calculated, and the failure cost (endodontic treatment + restoration) was added to the final cost, according to the 5-year failure rates of each therapy (20% for SCR and 44% for SW). A public health service unit composed of three dentists in 4-hour work shifts was used to calculate the monetary value of the treatments, assuming a total of 528 treatments/month. Considering the 229 teeth evaluated after 5 years (115 SCR and 114 SW), SCR provided savings of 43% (amalgam) and 41% (resin composite) per treatment, compared to SW. The SCR technique provides benefits for public finances (direct economy) and for public health services (increase in the number of treatments performed). Considering that maximizing profit and reducing costs are powerful motivating factors for adopting a certain treatment, this study provides data to better support the decision-making process, regarding the management of deep caries lesions in permanent molars. [ABSTRACT FROM AUTHOR]

Objective: To evaluate and compare bite force (BF) in permanent first molars restored with glass ionomer cement (GIC), composite and amalgam, and normal contralateral permanent first molars. Material and Methods: BF was recorded in decayed permanent first molars, which were filled with GIC (n=30), composite (n=30), and amalgam (n=30), and in healthy contralateral first molars (n=90) with Force Transducer Occlusal Force Meter and compared. Results: BF was significantly higher in normal teeth on the contralateral side compared to teeth restored with GIC and composite. However, in patients with amalgam restoration, though it was less compared to that on the contralateral side, it was not statistically significant (p>0.05). Conclusion: Restoring teeth with various filling materials may improve bite force. In the present study, it was found that the teeth restored with amalgam had higher bite forces in comparison to the other restorative materials used. However, it was not comparable to that observed in the normal tooth (control) on the contralateral side. [ABSTRACT FROM AUTHOR]

Among the pillars of sustainability in health care units is environmental protection. Although an EU-wide dental amalgam phase-out legislation exists, quantities of this material are still to be found in the market, dental offices or in the mouths of patients. The purpose of this study is to record the views of dentists and dental students in Greece regarding the use and safety of dental amalgam for people and the environment as well as their attitudes towards its restriction and disposal. Materials and methods: Two different questionnaires, through Google forms, were filled by each group. Descriptive statistics were used to describe the variables. The chi-square test or the chi-square test with Yates correction was used to examine potential differences per group (p-value = 0.05). Overall, 564 people participated in this study; 462 (81.9%) dentists (N1) and 102 (18.1%) dental students (N2). Results: Both groups agreed that they no longer use dental amalgam often. Dentists (39.8%) and students (36.4%) consider amalgam to have a moderate burden on the environment. This answer differed significantly per year of profession and year of undergraduate studies, respectively, with dentists from 6–25 years in the profession and 4th-year students, being the least aware on the environmental footprint of dental amalgam. Further, professionals (70%) and students (60%) believe that dental amalgam has a hazardous impact on patient's health, at all or to a small extent. For staff health, dentists reported at a moderate degree dangerous impact (32.9%) while students (36.4%), respectively. The impact on patients and staff health, were found to differ significantly per region of practicing dentistry for both groups. Finally, there were suggestions made from both groups about the necessity of information sharing on amalgam and mercury safety and the impact on the environment at the level of professional organizations. Conclusions: Students, younger dentists and those living in non-urban regions seem to be more sensitive to the environmental impact of amalgam use, disposal, and health of people. Environmental issues should be addressed thoroughly by professional organizations, enhancing relevant activities for all people involved. [ABSTRACT FROM AUTHOR]

Introduction: This study was conducted to evaluate and compare the effect of using three adhesive systems on the shear bond strength between composite resin and fresh amalgam. Materials and Methods: Amalgam samples were assigned into three groups according to the adhesive systems being used prior to the composite resin application. Group A (n = 10): universal self-etch bonding system (Single Bond Universal Adhesive, 3M, Neuss, Germany) was applied and light cured. Group B (n = 10): universal self-etch bonding was applied and light cured, followed by a thin layer of nanohybrid flowable composite (Tetric N-Flow, Ivoclar Vivadent, Liechtenstein), then light cured. Group C (n = 10): self-adhesive dual-cure luting resin cement (Calibra Universal, Dentsply Sirona, Charlotte, NC) was applied in equal quantity for each sample over amalgam surface. Composite resin was then applied by plastic instrument in a single increment to the height of the hole (2 mm), then celluloid strip was placed and light cured. After thermocycling, a shear bond test was performed. Results: Resin luting cement interface showed the higher significant bond strength, followed by universal bonding agent − flowable composite interface. The universal bonding interface group yielded the lowest results. Conclusion: The application of self-adhesive dual-cure luting resin cement resulted in significant increase in bond strength between composite resin and fresh amalgam.

Introduction: Dental amalgam is a dental material that has been used to fill carious cavities for more than 150 years. Amalgam fillings contain about 50% mercury and a mixture of other metals. The mercury it contains is controversial and debated by many researchers, as there is evidence of its negative effects on the human body. The constant release of mercury vapor from amalgam fillings is causing more and more countries to discontinue its use in treating patients' teeth. Aim of the study: The purpose of this study is to focus on evaluating the local and systemic effects of dental amalgam contained in dental fillings on human health. Materials and methods: PubMed and Google Scholar medical databases were analyzed, operating with the following keywords: dental amalgam, mercury, health effects, dentistry in as many configurations as needed. Thirty-four related articles published during the last five years (2017-2022) were selected. Results: Dental amalgam is a potential factor in many health problems among patients. Mercury's ease of penetration across the blood-brain barrier and the placenta means that it can cause adverse health effects from the prenatal period onward. Conclusions: Research on the effects of mercury from dental amalgams should continue in order to explore cause-and-effect sequences and deepen our understanding of the health implications. The search for an ideal restorative material for tooth tissue after dental treatment should be accelerated.

The conventional restorative materials amalgam and glass ionomer have multifarious drawbacks leading to introduction of newer materials with superior biomechanical attributes. The present study aimed to assess and compare the compressive strength of ceramicreinforced glass ionomer cement, zirconia-reinforced glass ionomer cement, high strength glass ionomer posterior restorative material, alkasite restorative material, and amalgam when used as posterior restorative materials. Materials and Methods: Five restorative materials were evaluated: modified glass ionomer cements including ceramic-reinforced, zirconia-reinforced, and high strength glass ionomer; alkasite restorative material; and dental amalgam. Fifty cylindrical specimens were fabricated using test materials (n = 10 for each group). Class II cavities prepared on 50 intact permanent molars were restored with test materials. After thermocycling and 24h of storing, the specimens in artificial saliva, compressive strength, and fracture resistance were tested. Data were analyzed statistically. One-way analysis of variance and post hoc Tukey test were used for intergroup comparison. Pearson’s correlation was used for correlating the maximum load by cylindrical and tooth specimens. Results: A significantly high compressive strength was displayed by specimens of group 4, followed by group 5, group 3, group 1, and least by group 2. The highest fracture resistance was displayed by teeth restored with the test materials in group 4, group 1, group 5, group 2, and least by group 3. Conclusion: Within the limitations of the present study, alkasite restorative material (Cention N) showed the highest compressive strength in cylindrical and highest fracture resistance in tooth specimens. [ABSTRACT FROM AUTHOR]