Health Implications of Dental Amalgam

Dental amalgam is one of the most widely used, but also the most controversial of dental restorative materials. Since its introduction during the first half of the 19 th century, concerns have been raised about health hazards related to the toxicity of a major component of amalgam, mercury. This has been a particularly contentious issue in Swed en, where amalgam use was discontinued in 2009, on environmental grounds. Two aspects of particular concern are the release of mercury vapour from dental amalgam fillings in patients and occupational exposure to mercury in clinical dental personnel handl ing amalgam. The aims of this thesis were twofold: to follow the progress of patients with health problems which they attribute to dental amalgam fillings and secondly, to investigate whether the offspring of female dental personnel handling amalgam were a t increased risk of adverse effects from potential exposure to mercury vapour in utero . In Study I we examined symptoms, perceived health changes over time and health - related quality of life (HRQoL) among applicants for subsidized replacement of amalgam f illings . We used a questionnaire to collect data. The results showed that the applicants had a wide range of symptoms and that their HRQoL was much poorer than in the general population in Sweden. Study II documented the use of social security benefits b y applicants for replacement of amalgam fillings . The data were retrieved from Swedish registers for the years 1994 to 2006. The cohort of dental filling replacement patients had a significantly higher number of days on sick leave and disability pension t han the general population. These differences increased during follow - up. In the replacement cohort, the highest number of sick - leave days was recorded in the year they applied for subsidi z ed replacement of fillings. While sick leave decreased following the year of application, the number of days on disability pension increased and peaked at the end of follow - up. Study III compared cognitive function among the sons of female dentists and dental nurses with that of sons of female physicians and assistant nurses. The aim was to determine whether the sons of female dentists and dental nurses had been harmed by the mothers’ potential occupational exposure to mercury while handling amalgam. The cognitive test scores were for a test undergone by all young men in Sweden when they were conscripted for military service. Data were retrieved from national registers. Sons of dental workers had cognitive function test results similar to, or higher than their comparison cohorts. Study IV investigated the risk of earl y mortality among the sons of female dental personnel. Using data from the national registers, neonatal, infant and childhood mortality rates were compared for the sons of dental and of non - dental health care personnel. The sons of female dentists were com pared with those of female physicians and the sons of female dental nurses with those of female assistant nurses. Analysis of data from the 1960’s disclosed a statistically significantly higher risk of neonatal mortality among the sons of dental nurses tha n the sons of assistant nurses. In the subsequent two decades, this difference no longer reached statistical significance and a trend test demonstrated a consistent decrease in risk over the three decades (1960’s, 1970’s and 1980’s). The following conclusions may be drawn from the results of the studies: A) In patients who attribute their poor health to their amalgam fillings, replacement of the fillings does not seem to lead to marked improvement in quality of life; HRQoL is well below the national averag e. Nor does filling replacement facilitate a return to workforce participation: in the years following filling replacement, these patients remain largely reliant on sick - leave or disability benefits. While the decreasing use of amalgam in recent years and its discontinuation from 2009 should lead to fewer and fewer people claiming amalgam - related ill - health, failure of current measures to improve the HRQoL in these patients and facilitate their return to the workforce is not only un satisfactory for the indi vidual patients, but also unacceptable to society. Further research is warranted to find ways of improving the status of these patients. B) There is no evidence that exposure to mercury vapour in utero has an adverse effect on the cognitive function of the of fspring of female dental professionals who handled amalgam during pregnancy. For the decade of highest use of amalgam, higher rates of neonatal mortality, but not of infant or childhood mortality, were disclosed among the offspring of female dental profess ionals. C) In Sweden, amalgam use decreased during the 1970’s and 1980’s and was finally discontinued in 2009. Thus the potential hazards of mercury exposure from amalgam fillings in patients and occupational exposure in dental personnel handling amalgam, n o longer apply in Sweden. Nevertheless, these findings on the health implications of dental amalgam, reliably supported by the Swedish national registers, provide an important frame of reference for countries with high caries activity, where amalgam use re mains high

Prophylactic antibiotics for staged bone augmentation in implant dentistry

Background: The objective of the study was to assess the effect of prophylactic antibiotics on the outcome of bone augmentation and subsequent dental implant placement by combining the recommended quality assessment methods for systematic reviews and primary studies. Materials and methods: This is a complex systematic review in which systematic reviews as well as primary studies are scrutinised. A search of Medline (OVID), The Cochrane Library (Wiley) and EMBASE, PubMed and Health technology assessment (HTA) organisations as-well as a complementary hand-search was carried out. Selected primary studies were assessed using GRADE. Each study was reviewed by three authors independently. Results: Abstract screening yielded six potential systematic reviews allocated for full-text inspection. A total of ten primary studies were read in full-text. No relevant systematic reviews regarding the topic of this article were found. The quality assessment resulted in two primary studies with a moderate risk of bias. Of the two studies with a moderate risk of bias, one compared a single dose of clindamycin 600 mg preoperatively with the same preoperative dose followed by four doses of 300 mg every 6 h. The second study compared a single dose prophylaxis of two different types of antibiotic compounds. Conclusion: In conclusion, the scientific evidence regarding the use of antibiotic prophylaxis for reducing the risk of infection in conjunction with bone augmentation procedures during dental implant placement is very limited. The infection rate as compared to nonusage of prophylactic antibiotics, selection of the most suitable compound, and the optimal duration of prophylactic treatment is still unknown.publishedVersio

Malocclusions and quality of life among adolescents : a systematic review and meta-analysis

BACKGROUND: Malocclusions in adolescents might have a negative impact on oral health-related quality of life (OHRQoL). Potential confounding variables (confounders) such as age, gender, caries, and socioeconomic status may skew the real relationship between malocclusions and OHRQoL. OBJECTIVES: To analyse the effect of malocclusions in adolescents on OHRQoL, when controlled for potential confounders. SEARCH METHODS: Five databases (PubMed, Cochrane Library, Cinahl, Scopus, and Web of Science) were searched up to 15 June 2022. SELECTION CRITERIA: Studies in which OHRQoL in 10-19-year olds with and without malocclusions were compared. DATA COLLECTION AND ANALYSIS: Screening, data extraction, and quality assessments were performed by four investigators independently. Risk of bias was assessed according to the Swedish Agency for Health Technology Assessment and Assessment of Social Services (SBU) guidelines. To be included, studies had to control for confounders. Certainty of evidence was assessed with GRADE. RESULTS: Thirteen cross-sectional studies with low and moderate risk of bias were included in the qualitative synthesis. Four of these were also included in the quantitative synthesis (meta-analysis). The 13 studies in the qualitative synthesis displayed a large variation among the indices used for malocclusion ratings, as well as in instruments measuring OHRQoL. There was moderate quality of evidence that malocclusions have a negative effect on OHRQoL. The four articles included in the quantitative synthesis (meta-analysis) measured malocclusions with DAI and OHRQoL with CPQ 11-14 short form. There was moderate quality of evidence that malocclusions have a negative effect on OHRQoL (RR/PR 1.15, 95% CI 1.12-1.18, 3672 participants). CONCLUSIONS: There is moderate quality of evidence that malocclusions in adolescents have a negative impact on OHRQoL, after taking relevant confounders into consideration. Future studies should ideally use standardized measures for malocclusion ratings and OHRQoL. REGISTRATION: PROSPERO. CRD42020186152

Swedish quality registry for caries and periodontal diseases (SKaPa) : validation of data on dental caries in 6- and 12-year-old children

Background The Swedish Quality Registry for caries and periodontal disease (SKaPa) automatically collects data on caries and periodontitis from patients’ electronic dental records. Provided the data entries are reliable and accurate, the registry has potential value as a data source for registry-based research. The aim of this study was to evaluate the reliability and accuracy of the SKaPa registry information on dental caries in 6- and 12-year-old children. Method This diagnostic accuracy study compared dental caries data registered at an examination with dental health status registered in the patient’s electronic dental records, and with corresponding data retrieved from the SKaPa registry. Clinical examinations of 170 6- and 12-year-old children were undertaken by one of the researchers in conjunction with the children’s regular annual dental examinations where the number of teeth were registered, and dental caries was diagnosed using ICDAS II. Teeth with fillings were defined as filled and were added to the ICDAS II score and subsequently dft/DFT was calculated for each individual. Cohen’s Kappa, the intraclass correlation coefficient (ICC), and sensitivity and specificity were calculated to test the agreement of the ‘decayed and filled teeth’ in deciduous and permanent teeth (dft/DFT) from the three sources. Results Cohen’s Kappa of the dft/DFT-values was calculated to 0.79 between the researcher and the patient record, to 0.95 between patient dental record and SKaPa, and to 0.76 between the researcher and SKaPa. Intraclass correlation coefficient (ICC) was calculated to 0.96 between the researcher and the patient journal, to 0.99 between the patient dental record vs. SKaPa, and to 0.95 between the researcher and SKaPa. Conclusion The SKaPa registry information demonstrated satisfactory reliability and accuracy on dental caries in 6- and 12-year-old children and is a reliable source for registry-based research.Trial registration The study was registered in Clinical Trials (www.ClinicalTrials.gov, NCT03039010)</p

Impact of direct oral anticoagulants on bleeding tendency and postoperative complications in oral surgery : a systematic review of controlled studies

OBJECTIVE: The recommendations for the management of direct oral anticoagulants (DOACs) in oral surgery are inconsistent. The present review evaluated whether DOACs increase the risk of bleeding during oral surgery and postoperative complications. STUDY DESIGN: The patients undergoing oral surgery and receiving a DOAC were compared with the patients receiving a DOAC different from the exposure, a vitamin K antagonist (VKA), or no anticoagulant. Three electronic databases were searched for eligible clinical trials and systematic reviews. The risk of bias was assessed, data were extracted, a meta-analysis was done, and the Grading of Recommendations, Assessment, Development and Evaluations certainty-of-evidence ratings were determined. RESULTS: Three clinical trials comparing patients receiving DOAC medication with patients on a VKA were eligible. A meta-analysis of bleeding 7 days postoperatively detected no significant differences between patients continuing DOAC or VKA medication during and after surgery. All of the point estimates favored uninterrupted DOAC over VKA therapy. Tranexamic acid was topically administered to some patients. CONCLUSIONS: Based on an interpreted trend among 3 studies with mixed patient populations, the risk of bleeding during the first 7 postoperative days may be lower for patients on uninterrupted DOAC than VKA therapy (⨁⨁⭘⭘), but the effect size of the risk is unclear. 80 of 274 included patients experienced postoperative bleeding

General joint hypermobility in temporomandibular joint disease; clinical characteristics, biomarkers, and surgical aspects

Objectives: This study aimed at identifying biomarkers in the temporomandibular joint (TMJ) synovial tissue analysing 28 extra cellular matrix proteins in TMJ diseased patients, classified with either general joint hypermobility (GJH) or normal joint mobility (NJM), and to compile clinical and protein characterisation to reveal potential surgical predictive factors. Study design: A prospective observational cohort study including 97 consecutive patients scheduled for TMJ surgery was performed. Joint mobility and several other predefined clinical variables were recorded. Synovial tissue was harvested during surgery followed by examination using multi-analytic profiling. A multivariate quantile regression model was used for analysis purposes. Results: The GJH/NJM ratio was 2:5. The GJH cohort were younger (P = 0.001) and more likely to be women (P = 0.026) compared to the NJM cohort. None of the protein concentrations could be correlated to joint mobility in the multivariate regression model, but often to the variable TMJ diagnosis. The surgical outcome after the six-month follow-up were equal between GJH and NJM patients. Conclusions: GJH was more common in the study cohort compared to general population frequencies, but GJH was not a negative factor for surgical outcome. Young age and female gender correlated to GJH. No TMJ biomarkers were GJH specific, and the results suggested that TMJ diagnosis more strongly correlated to the protein profile compared to GJH and the other investigated variables

The risk for infraposition of dental implants and ankylosed teeth in the anterior maxilla related to craniofacial growth, a systematic review

Background The aim of the study was to evaluate a potential association between individuals with different craniofacial types or other exposures, and the risk of infraposition due to continued growth/eruption of adjacent teeth in the anterior maxilla. Materials and methods This is a systematic review in which primary studies as well as other systematic reviews are scrutinised. A search of PubMed (Medline), Scopus, Web of science and Health technology assessment (HTA) organisations and a complementary handsearch was carried out. Selected studies were read in full-text by several reviewers. The quality of the included primary studies was assessed using a protocol for assessment of risk of bias in exposure studies. Results The literature search resulted in 3,296 publications. Title and abstract screening yielded 25, whereof one systematic review, potential publications allocated for full-text inspection. The quality assessment resulted in a total of seven studies with a low/moderate risk of bias and four studies with a high risk of bias. Conclusion In conclusion, a long-term risk for infraposition of dental implants, or ankylosed teeth, among natural teeth can be observed in some cases. The predisposing factors are still not fully understood since the current scientific evidence is very limited

Study on self-assessment regarding knowledge of temporomandibular disorders in children/adolescents by Swedish and Saudi Arabian dentists

OBJECTIVE: To estimate the degree of self-assessed knowledge among dentists in Sweden and Saudi Arabia regarding temporomandibular disorders (TMD) in children and adolescents using a summative form of assessment and further to investigate the possible factors that may influence the self-assessed knowledge. MATERIALS AND METHODS: A questionnaire survey covering four domains (Etiology; Diagnosis and classification; Chronic pain and pain behavior; Treatment and prognosis) regarding TMD knowledge was used. Out of 250 questionnaires (125 in each country) a total of 65 (52%) were returned in Sweden and 104 (83%) in Saudi Arabia. RESULTS: Self-assessed individual knowledge was significantly associated to the level of actual knowledge among the Swedish groups in the domains Etiology; Diagnosis and classification and Treatment and prognosis (p < 0.05). However, in the Saudi Arabian groups a corresponding significant association was only found in the domain Diagnosis and classification (p < 0.05). CONCLUSIONS: This study showed that there is a difference in the accuracy of self-assessment of own knowledge between the dentists in Sweden and Saudi Arabia. The Swedish dentists have a better ability to assess their level of knowledge compared to Saudi Arabian dentists regarding TMD in children and adolescents. This difference could be related to several factors such as motivation, positive feedback, reflection, psychomotor, and interpersonal skills, which all are more dominant in the Swedish educational tradition