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Dental amalgam from dental clinics in Kosova is an uncontrolled source of mercury. The environmental legislative framework related to its use does not fully provide measures that reduce amalgam use and the release of its waste into the environment. This paper highlights issues related to environmental policy covering mercury amalgam waste management. Existing national regulations on hazardous waste management in Kosova consider the waste from dental health care as hazardous. Currently, however, no regulations restrict the use of dental amalgam or specifically oblige the generators of amalgam to treat or dispose of waste properly, thus leading to inconsistent legislation. New regulations, revised hazardous waste management standards, and new infrastructure for waste treatment and disposal, in compliance with EU regulations, should be developed to create a holistic approach that prevents the adverse effects of amalgam waste. Integr Environ Assess Manag 2021;17:1037-1044. © 2021 SETAC.

Background Root canal therapy is a sequence of treatments involving root canal cleaning, shaping, decontamination and obturation. It is conventionally performed through a hole drilled into the crown of the affected tooth, namely orthograde root canal therapy. For teeth that cannot be treated with orthograde root canal therapy, or for which it has failed, retrograde root filling, which seals the root canal from the root apex, is a good alternative. Many materials, such as amalgam, zinc oxide eugenol and mineral trioxide aggregate (MTA), are generally used. Since none meets all the criteria an ideal material should possess, selecting the most efficacious material is of utmost importance. Objectives To determine the effects of different materials used for retrograde filling in children and adults for whom retrograde filling is necessary in order to save the tooth. Search methods Cochrane Oral Health's Information Specialist searched the following databases: Cochrane Oral Health's Trials Register (to 13 September 2016); the Cochrane Central Register of Controlled Trials (CENTRAL; 2016, Issue 8) in the Cochrane Library (searched 13 September 2016); MEDLINE Ovid (1946 to 13 September 2016); Embase Ovid (1980 to 13 September 2016); LILACS BIREME Virtual Health Library (1982 to 13 September 2016); and OpenSIGLE (1980 to 2005). ClinicalTrials.gov and the World Health Organization International Clinical Trials Registry Platform were searched for ongoing trials. We also searched Chinese BioMedical Literature Database (in Chinese, 1978 to 20 September 2016); VIP (in Chinese, 1989 to 20 September 2016); China National Knowledge Infrastructure (in Chinese, 1994 to 20 September 2016); and Sciencepaper Online (in Chinese, to 20 September 2016). No restrictions were placed on the language or date of publication when searching the electronic databases. Selection criteria We selected randomised controlled trials (RCTs) only that compared different retrograde filling materials, with reported success rate that was assessed by clinical or radiological methods for which the follow-up period was at least 12 months. Data collection and analysis Two review authors extracted data independently and in duplicate. Original trial authors were contacted for any missing information. Two review authors independently carried out risk of bias assessments for each eligible study following Cochrane methodological guidelines. Main results We included six studies (916 participants with 988 teeth) reported in English. All the studies had high risk of bias. The six studies examined five different comparisons, including MTA versus intermediate restorative material (IRM), MTA versus super ethoxybenzoic acid cement (Super-EBA), Super-EBA versus IRM, dentine-bonded resin composite versus glass ionomer cement and glass ionomer cement versus amalgam. There was therefore little pooling of data and very little evidence for each comparison. There is weak evidence of little or no difference between MTA and IRM at the first year of follow-up (risk ratio (RR) 1.09; 95% confidence interval (CI): 0.97 to 1.22; 222 teeth; quality of evidence: low). Insufficient evidence of a difference between MTA and IRM on success rate at the second year of follow-up (RR 1.06; 95% CI: 0.89 to 1.25; 86 teeth, 86 participants; quality of evidence: very low). All the other outcomes were based on a single study. There is insufficient evidence of any difference between MTA and Super-EBA at the one-year follow-up (RR 1.03; 95% CI: 0.96 to 1.10; 192 teeth, 192 participants; quality of evidence: very low), and only weak evidence indicating there might be a small increase in success rate at the one-year follow-up in favour of IRM compared to Super-EBA (RR 0.90; 95% CI: 0.80 to 1.01; 194 teeth; quality of evidence: very low). There was also insufficient and weak evidence to show that dentine-bonded resin composite might be a better choice for increasing retrograde filling success rate compared to glass ionomer cement at the one-year follow-up (RR 2.39; 95% CI: 1.60 to 3.59; 122 teeth, 122 participants; quality of evidence: very low). And there was insufficient evidence of a difference between glass ionomer cement and amalgam at both the one-year (RR 0.98; 95% CI: 0.86 to 1.12; 105 teeth; quality of evidence: very low) and five-year follow-ups (RR 1.00; 95% CI: 0.84 to 1.20; 82 teeth; quality of evidence: very low). None of these studies reported an adverse event. Authors' conclusions Based on the present limited evidence, there is insufficient evidence to draw any conclusion as to the benefits of any one material over another. We conclude that more high-quality RCTs are required.

Aim To assess whether the timing of pulp disease after tooth restoration was associated with type of restorative dental material used, extent of the restoration or tooth type. Methodology A comprehensive search and analysis of data using the Titanium Oral Health Management software program at The Oral Health Centre of Western Australia were performed to correlate procedural codes for teeth that had restorations placed and subsequently developed pulp disease requiring endodontic treatment or extraction from 1st January 2009 to 31st December 2013. Manual analysis of paper and/or electronic patient record cards was also performed. Data collected included restoration type, restored tooth surfaces, tooth type and the dates of restoration and subsequent endodontic intervention or extraction. Results Of 330 teeth that met the inclusion criteria, 84 (26%) had composite resin restorations, 80 (24%) had amalgams, 119 (36%) had glass-ionomer cement (GICs), and 47 (14%) had crowns. The average time between restoration and further intervention was 330 days with a range from 3 to 1775 days (approximately 5 years). Teeth restored with crowns or five-surface restorations were significantly more likely to require earlier intervention than other restorations. Premolar and anterior teeth were also more likely to require earlier intervention. Conclusions Teeth that developed pulp disease requiring further intervention that were restored with crowns and five-surface GIC developed the disease sooner than teeth that were restored with amalgam or composite. In teeth with five-surface restorations that developed pulp disease requiring further intervention, premolar and anterior teeth developed the pulp disease sooner than molars.

Lichen planus pigmentosus is uncommon in childhood and its treatment is often challenging. We report a case of cutaneous lichen planus pigmentosus in a 10-year-old boy, without oral mucosal involvement, two months after an amalgam dental restoration. The diagnosis was based on the histopathological examination of a skin biopsy, the positive patch test to mercury, and the improvement after amalgam removal. Our case report suggests that metal allergy may play a role, and amalgam replacement may be followed by clinical improvement.

ERZURUMLU, ZERRIN UNAL/0000-0002-8693-1206; Guler, Cigdem/0000-0002-2581-9050 WOS: 000479834400001 PubMed: 31368622 The aim of this article is to compare the effects of 1.5 T and 3 T MRI on microleakage of amalgam restorations. A total of 90 extracted molar teeth were used in this study. Amalgam was used to restore standard Class V preparations (5 x 3 x 2 mm). Following the restoration, the teeth were divided into three groups according to magnetic resonance imaging (MRI) protocol (Group I: Control, Group II: 1.5 T MRI, and Group III: 3 T MRI). A total of 6,000 thermal cycles at 5 degrees C-55 degrees C were applied on all samples. Microleakage values were measured in millimeters using the ImageJ program. Microleakage values were higher in the gingival region compared to the occlusal region in all groups and the differences were statistically significant (p < .05). Microleakage values were not statistically different among the groups in the occlusal region (p > .05), while there were statistically significant differences among the groups with respect to microleakage values in the gingival region (p < .01). The highest mean microleakage amount in the gingival region was measured in Group III (1.192 +/- 0.941 mm). This was followed by Group II (0.519 +/- 0.813 mm) and Group I (0.347 +/- 0.726 mm), respectively. Within the limitations of this in vitro study, we observed that higher microleakage values in amalgam restored teeth in which were exposed to MRI procedure. We also found that the teeth exposed to the stronger magnetic field showed higher microleakage amount.

Objective Questions have been raised about potential risks of prenatal exposure to mercury from amalgam fillings during pregnancy. The aim of this study was to assess possible associations between exposure to amalgam fillings in pregnant women participating in a large cohort study and adverse pregnancy outcome. Methods In the Norwegian Mother and Child Cohort Study (MoBa), a valid information about the number of teeth with amalgam fillings and dental treatment, including new amalgam fillings placed or removed during pregnancy, was available from 69 474 pregnancies. The information was obtained from two questionnaires sent to the women at 17 and 30 weeks of pregnancy, and the data were linked to the Medical Birth Registry of Norway. Logistic regression was used to estimate the odds ratio (OR) and 95% confidence intervals (95% CI) as a measure of association between pregnancy outcome and prenatal exposure to amalgam fillings. Results Logistic regression models, including mothers′ age, education, BMI, parity, smoking during pregnancy, and alcohol consumption during pregnancy revealed no significant associations between the number of teeth with amalgam fillings and early preterm delivery, late preterm delivery, low birthweight, malformation or stillbirth. Conclusions We found no evidence for serious perinatal consequences of maternal exposure to amalgam fillings during pregnancy.

Dental education consists of both theoretical and practical learning for students to develop competence in treating patients clinically. When dental students encounter practical courses in their first year as a new educational experience, they must also learn to evaluate themselves. Self-evaluation is an essential skill to learn for dental professionals to keep increasing their competence over the course of their careers. The aim of this study was to compare the assessment scores of second- and third-year dental students and the faculty in two consecutive preclinical practical exams in restorative dentistry courses in a dental school in Turkey. Faculty- and student-assigned scores were calculated from two consecutive preclinical examinations on tooth restorations performed on both artificial casts and phantom patients. The students were formally instructed on grading procedures for tooth preparations, base and restoration placement, and polishing criteria. After each step, each item was assessed by faculty members, the student, and another student. The results indicated that the initial differences between second-year students' assessments of their own preclinical practical ability and that of the faculty decreased among the third-year students. Self-evaluation scores did not indicate whether the third-year students tended to over- or underestimate the quality of their own work. However, the second-year students not only overestimated themselves but thought they were above average. The results point to the need to develop students' self-insight with more exercises and practical training.

The extra-alveolar dry period and storage medium in which the tooth was kept prior to replantation remain the critical factors affecting the survival and regeneration of the damaged periodontium. When the replantation is delayed, replacement root resorption is the most common complication following replantation of an avulsed tooth. The aim of this histological study was to evaluate the periodontal healing of replanted dogs' teeth after 20 min (short) and 60 min (long) extraoral dry time with and without the application of enamel matrix proteins. Eighty mature premolar roots (40 teeth) maxillary and mandibular premolars were extracted, the root canals were accessed, instrumented, and filled using a lateral condensation technique, and the access cavity was restored with amalgam. Each root was randomly assigned to one of experimental groups: Groups I and II: Roots were replanted after an extraoral dry time of 20 min. In group II, Emdogain(®) (Biora, Malmo, Sweden) was applied directly to the external root surface with complete coverage. Groups III and IV: Roots were replanted after an extraoral dry time of 60 min. In group IV, Emdogain(®) was applied to the whole external root surface before replantation. Roots that replanted within a total extraoral dry time of 10 min were used as negative controls, while those replanted after 90 min of extraoral dry time were assigned as positive controls. After 4 months, the dogs were euthanized, and the maxillary and mandibular processes were processed for histology and microscopically evaluated. Statistical analysis showed no significant differences (P = 0.1075) among the experimental groups. The results of this study show that 20 min of extraoral dry time is as detrimental to the PDL cells as 60 or 90 min of extraoral dry time, with avulsed dogs' teeth, even when replanted with an inductive material such as EMD. This study provides strong evidence in relation to the threshold of the extraoral dry time of avulsed teeth, suggesting that the extraoral dry time threshold of PDL cell viability is significantly less than that which current guidelines promote.

The aim of the study was to determine the prognosis and to evaluate the regression of lichenoid contact reactions (LCR) and oral lichen planus (OLP) after replacement of dental restorative materials suspected as causing the lesions. Forty-four referred patients with oral lesions participated in a follow-up study that was initiated an average of 6 years after the first examination at the Department of Odontology, i.e. the baseline examination. The patients underwent odontological clinical examination and answered a questionnaire with questions regarding dental health, medical and psychological health, and treatments undertaken from baseline to follow-up. After exchange of dental materials, regression of oral lesions was significantly higher among patients with LCR than with OLP. As no cases with OLP regressed after an exchange of materials, a proper diagnosis has to be made to avoid unnecessary exchanges of intact restorations on patients with OLP.

Occupational and Environmental Expo- sure to Mercury among Iranian Hairdressers: Hoda FAKOUR, et al. Department of Environment, Faculty of Natural Resources and Marine Sciences, Tarbiat Modares University, Iran—Objectives: The aim of this study was to describe the mercury concentrations in female hairdressers associated with occupational and environmental exposure through cosmetic products and amalgam fillings. Methods: Sixty-two hair and nail samples were collected randomly from Iranian hair- dressers. Hg level determination was carried out using a LECO, AMA 254, Advanced Mercury Analyzer accord- ing to ASTM, standard No. D-6722. Results: The mean mercury levels were 1.15 ± 1.03 µg/g and 1.82 ± 1.12 µg/g in the hair and nail samples, respectively with a positive correlation among them (r=0.98). A significant relation was also observed between Hg levels and the number of amalgam fillings (p

Aim To investigate amongst Greek endodontists, the incidence of ocular accidents during practice, the circumstances associated with them, the therapeutic measures taken after the accidents, their compliance with the use of eye protection and their eye care behaviour. Methodology One hundred and forty-seven endodontists met the inclusion criteria and were invited to participate in the survey. Data were gathered through interviews based on a questionnaire. Participants were asked for personal/professional data, information on ocular accidents in the past 5 years, post-accident actions and the type of eye protection used. Their eyesight status and frequency of ocular examination were also recorded. Data were analysed using chi-square test, independent samples t-test and logistic regression. The level of significance was set at P = 0.05. Results The response rate was 84%. Ocular accidents were reported by 73% of the participants. Amalgam and NaOCl were the foreign bodies most frequently associated with ocular accidents. Medical assistance was sought in 16% of the most recent accidents. No permanent eye damage was reported. Regular use of magnification (OR:0.305, 95%CI:0.123–0.754) and years of clinical experience (OR:0.191, 95%CI:0.066–0.551) were significant predictors for the incidence of ocular accidents. Adequate eye protection was utilized by 82% of endodontists. Endodontists with eyesight deficiencies attended more frequently for ocular examination (P = 0.018). Conclusion A high percentage of endodontists experienced ocular accidents. Regular use of magnification and increasing years in practice were associated with a reduced risk of ocular accidents. The majority of endodontists reported using adequate eye protection.

Background Childhood caries (tooth decay) consists of a form of tooth decay that affects the milk teeth (also known as baby or primary teeth) of children. This may range from tooth decay in a single tooth to rampant caries affecting all the teeth in the mouth. Primary teeth in young children are vital to their development and every effort should be made to retain these teeth for as long as is possible. Dental fillings or restorations have been used as an intervention to repair these damaged teeth. Oral health professionals need to make astute decisions about the type of restorative (filling) material they choose to best manage their patients with childhood caries. This decision is by no means an easy one as remarkable advances in dental restorative materials over the last 10 years has seen the introduction of a multitude of different filling materials claiming to provide the best performance in terms of durability, aesthetics, symptom relief, etc when placed in the mouth. This review sought to compare the different types of dental materials against each other for the same outcomes. Objectives The objective of this review was to compare the outcomes (including pain relief, survival and aesthetics) for restorative materials used to treat caries in the primary dentition in children. Additionally, the restoration of teeth was compared with extraction and no treatment. Search methods Electronic searches of the following databases were undertaken: the Cochrane Oral Health Group's Trials Register (up to January 2009); CENTRAL (The Cochrane Library 2009, Issue1); MEDLINE (1966 to January 2009); EMBASE (1996 to January 2009); SIGLE (1976 to 2004); and conference proceedings on early childhood caries, restorative materials for paediatric dentistry, and material sciences conferences for dental materials used for children's dentistry (1990 to 2008). The searches attempted to identify all relevant studies irrespective of language.Additionally, the reference lists from articles of eligible papers were searched, handsearching of key journals was undertaken, and personal communication with authors and manufacturers of dental materials was initiated to increase the pool of suitable trials (both published and unpublished) for inclusion into this review. Selection criteria Randomised controlled trials (RCTs) or quasi-randomised controlled trials with a minimum period of 6 months follow up were included. Both parallel group and split-mouth study designs were considered. The unit of randomisation could be the individual, group (school, school class, etc), tooth or tooth pair. Included studies had a drop-out rate of less than 30%. The eligible trials consisted of young children (children less than 12 years) with tooth decay involving at least one tooth in the primary dentition which was symptomatic or symptom free at the start of the study. Data collection and analysis Data were independently extracted, in duplicate, by two review authors. Disagreements were resolved by consultation with a third review author. Authors were contacted for missing or unclear information regarding randomisation, allocation sequence, presentation of data, etc. A quality assessment of included trials was undertaken. The Cochrane Collaboration statistical guidelines were followed for data analysis. Main results Only three studies were included in this review. The Fuks 1999 study assessed the clinical performance of aesthetic crowns versus conventional stainless steel crowns in 11 children who had at least two mandibular primary molars that required a crown restoration. The outcomes assessed at 6 months included gingival health (odds ratio (OR) 0.3; 95% confidence interval (CI) 0.01 to 8.32), restoration failure (OR 3.29; 95% CI 0.12 to 89.81), occlusion, proximal contact and marginal integrity. The odds ratios for occlusion, proximal contact and marginal integrity could not be estimated as no events were recorded at the 6-month evaluation. The Donly 1999 split-mouth study compared a resin-modified glass ionomer (Vitremer) with amalgam over a 36-month period. Forty pairs of Class II restorations were placed in 40 patients (21 males; 19 females; mean age 8 years +/- 1.17; age range 6 to 9 years). Although the study period was 3 years (36 months), only the 6- and 12-month results are reported due to the loss to follow up of patients being greater than 30% for the 24- and 36-month data. Marks 1999a recruited 30 patients (age range 4 to 9 years; mean age 6.7 years, standard deviation 2.3) with one pair of primary molars that required a Class II restoration. The materials tested were Dyract (compomer) and Tytin (amalgam). Loss to follow up at 24 and 36 months was 20% and 43% respectively. This meant that only the 24-month data were useable. For all of the outcomes compared in all three studies, there were no significant differences in clinical performance between the materials tested.No studies were found that compared restorations versus extractions or no treatment as an intervention in children with childhood caries. Authors' conclusions It was disappointing that only three trials that compared three different types of materials were suitable for inclusion into this review. There were no significant differences found in all three trials for all of the outcomes assessed. Well designed, randomised controlled trials comparing the different types of filling materials for similar outcomes are urgently needed in dentistry. There was insufficient evidence from the three included trials to make any recommendations about which filling material to use.

Ansari G, Ranjpour M. Mineral trioxide aggregate and formocresol pulpotomy of primary teeth: a 2-year follow-up. International Endodontic Journal, 43, 413–418, 2010. Abstract Aim To compare the clinical and radiographic response of primary teeth to vital pulpotomy using mineral trioxide aggregate (MTA) or formocresol (FC). Methodology A group of 17 children aged 4–9 were selected from those referred to the Paedodontic Department at Shahid Beheshti University, Dental School. Cases with at least two matching teeth were selected (40 teeth), showing signs of pulp involvement. A pulpotomy procedure was carried out in all cases with FC in control teeth whilst MTA was placed in experimental teeth. Clinical and radiographic evaluations were performed at 1-, 6-, 12- and 24-month recall. Statistical analysis using a Fischer exact test was performed on the data to determine significant differences between the groups. Results Overall, 22 second and 18 first primary molars were included. The gender ratio was one male to three female. No significant difference was found between the clinical and radiographic outcomes of the two groups at 6-, 12- and 24-month follow-up (P > 0.05). Internal resorption was seen significantly more often in FC cases after 12 months than MTA cases. Overall radiographic appearance of normal structures at 24th month was seen in more than 95% of the cases in MTA and 90% in the FC-treated group (P > 0.05). Conclusion Mineral trioxide aggregate for pulp treatment of primary teeth can be considered a replacement for FC.

Two patients presented with complaints of recurrent drainage of purulent exudate from sinus tracts, inflammation and pain after endodontic re-treatment of the maxillary left (Case 1) and right (Case 2) lateral incisors. The periapical lesions persisted after apical curettage, apicectomy and root-end filling with silver amalgam. Radiographic examination exposed the poor quality of the endodontic treatments and the silver amalgam root-end fillings, which were associated with periapical radiolucent areas in both teeth. The sinus tract persisted after root canal cleaning and shaping, followed by a calcium hydroxide root canal dressing. The root-end fillings were periapically dislodged with endodontic K-files, and showed progressive displacement by sinus tracts up to elimination in the oral cavity. Follow ups of 42 and 65 months post procedure revealed clinical disappearance of the symptoms, sinus tracts and exudates, and radiographs revealed that the repair process of the periapical radiolucent areas was quite advanced.

Background: Burning mouth syndrome is a burning sensation or stinging disorder affecting the oral mucosa in the absence of any clinical signs or mucosal lesions. Some studies have suggested that burning mouth syndrome could be caused by the metals used in dental prostheses, as well as by acrylate monomers, additives and flavouring agents, although others have not found any aetiologic role for hypersensitivity to dental materials. Objective: To evaluate the extent and severity of adverse reactions to dental materials in a group of patients with burning mouth syndrome, and investigate the possible role of contact allergy in its pathogenesis. Materials and methods: We prospectively studied 124 consecutive patients with burning mouth syndrome (108 males; mean age 57 years, range 41–83), all of whom underwent allergen patch testing between 2004 and 2007. Results: Sixteen patients (13%) showed positive patch test reactions and were classified as having burning mouth syndrome type 3 or secondary burning mouth syndrome (Lamey’s and Scala’s classifications). Conclusion: Although we did not find any significant association between the patients and positive patch test reactions, it would be advisable to include hypersensitivity to dental components when evaluating patients experiencing intermittent oral burning without any clinical signs.

Background: A 56-year-old female presented for periodontal treatment with a large amalgam tattoo located in alveolar mucosa on the facial aspect of her maxillary central incisors. The lesion had been present for 42 years since having endodontic surgery at teeth #8 and #9 after a traumatic childhood incident.Methods: A two-stage surgical approach was used to eliminate the lesion, beginning with a subepithelial connective tissue graft to increase tissue thickness subjacent to the amalgam tattoo. After 6 weeks of healing, the overlying pigmented tissue was removed using laser surgery to expose the underlying grafted connective tissue.Results: After 2 months of healing following laser surgery, the amalgam pigmentation was completely removed, with good color match and an increased width of keratinized tissue at the surgical site.Conclusion: A relatively large amalgam tattoo in the esthetic zone can be adequately removed by a two-stage procedure using grafted palatal connective tissue and laser deepithelialization.

Ceramic dental restorative materials offer an esthetic alternative to dental amalgam or gold. There is uncertainty relative to the longevity of ceramic inlay restorations. Recently published long-term research studies reveal general clinical performance trends. These trends are discussed while presenting a ceramic inlay case. Successful clinical use of ceramic inlay materials is absolutely dependent on the creation of an uncompromised adhesive tooth/ceramic interface. Ceramic inlay restorations perform well in terms of long-term retention, color match, and anatomic contour stability. These restorations all experience limited margin deterioration that does not predispose to marginal discoloration or secondary caries. Patients rarely suffer from postoperative sensitivity secondary to ceramic inlay placement. Ceramic inlays fail predominantly as a result of crack propagation from material flaws leading to bulk fracture. Some superficial ceramic defects may be repaired with composite resin. Internal material flaws are minimized by industrial production of indirect pressable glass-ceramic materials or ceramic blocks designed for computer-aided design/computer-assisted manufacturing (CAD/CAM). External surface flaws are limited by careful polishing techniques. Strategic placement of ceramic inlays in teeth that are not subject to heavy occlusal loading will result in more predictable long-term performance. Preparation design to prevent flexure of ceramic inlay materials is essential. CLINICAL SIGNIFICANCE Use of ceramic inlays to restore defects in posterior teeth requires careful attention to detail. Placement of ceramic inlay materials in high-stress areas may result in less predictable long-term performance. Ceramic inlays are advantageous for restoring moderately sized defects when optimal control of restoration contours and esthetics is desired.

Dental restorations, fixed prosthodontics, and implants affect dose distribution in head and neck radiation therapy due to the high atomic number of the materials utilized. The backscatter of electrons from metallic materials due to the impinging treatment x‐ray results in localized dose enhancements. These dose enhancements cause localized mucositis in patients who have dental work, a significant clinical complication. We investigated the backscatter effect of 23 configurations of dental work using the EGS4nrc Monte Carlo (MC) simulation system. We found that all‐metal fixed partial dentures caused the highest amount of dose enhancement – up to 33% – while amalgam restorations did not cause a significant amount. Restorations with a ceramic veneer caused up to 8% enhancement. Between 3 mm and 5 mm of water‐equivalent material almost completely absorbed the backscatter. MC simulations provide an accurate estimate of backscatter dose, and may provide patient‐specific estimates in future.

– Objective: To measure the 5-year caries increment among high-risk children during their participation in the New England Children’s Amalgam Trial (NECAT), and to evaluate sociodemographic factors that may account for any observed disparities. Methods: NECAT recruited 534 children aged 6–10 with at least two decayed posterior occlusal surfaces from urban Boston and rural Maine. After restoration of baseline caries and application of sealants to sound surfaces, NECAT continued to provide free comprehensive semiannual dental care to participants. The net caries increment of children who completed the 5-year follow-up (n = 429) was calculated and predictors of caries increment were investigated using multivariate negative binomial models. Results: The majority of children (89%) experienced new caries by the end of the 5-year follow-up. Almost half (45%) had at least one newly decayed surface by the first annual visit. At year 5, the mean number of new decayed teeth was 4.5 ± 3.6 (range 0–25) and surfaces was 6.9 ± 6.5 (range 0–48). Time trends showed a noticeably higher increment rate among older children and young teenagers. Multivariate models showed that age (P

Black's class I classic cavities were cut in 120 sound extracted human premolars and restored with one of two silver amalgams, six different base combinations, with or without cavity varnish and then aged for 3 months or 1 year. Thereafter, the restored teeth were subjected to a bacterial or acid broth in vitro carious challenge for 36 days. Resin cast impressions were made of the restoration margin of each specimen before and after the carious challenge giving a total of 240 replicas. The replicas were examined in a scanning electron microscope (SEM) and the margins subjected to seven marginal assessment procedures: (i) ranking using micrographs of the margin; (ii) percentage length of marginal discrepancy; (iii) Mjor assessment using six groups; (iv) number of margin segments showing a discrepancy; (v) greatest gap size; (vi) ranking based firstly on gap size and then number of margin segments showing a discrepancy; and (vii) ranking based firstly on gap size and then percentage length of marginal discrepancy. The data from procedures (i), (ii), (vi) and (vii) were examined using one-way ANOVA; a linear logistic statistical analysis examined data from procedures (iii)-(v). Statistical significance was chosen at P < 0.05. It was found that procedure (vii) was able to discriminate between variables to a greater degree than all other procedures. It is recommended that a ranking system based on greatest gap size and percentage length of marginal discrepancy be used to assess marginal quality of amalgam restorations.

The adherence of Streptococcus sanguis and S. mutans to seven restoratives in the presence and absence of an artificial salivary pellicle has been investigated. The physiochemical surface characteristics of the bacteria and of the restoratives were also measured, together with the effect of salivary coating of restoratives. Zeta potential of uncoated restoratives showed a positive correlation with the number of adherent S. mutans cells and S. sanguis cells. S. sanguis showed a positive correlation with the hydrophobicity of uncoated restoratives. The surface hydrophobicity was decreased upon saliva coating, whereas the zeta potential was slightly increased. The contact angles or zeta potentials of saliva-coated restoratives were positively correlated with those of uncoated restoratives. The number of adherent cells of both S. sanguis and S. mutans to saliva-coated restoratives were decreased after the coating. Zeta potential of saliva-coated restoratives showed a positive correlation with the numbers of adherent S. mutans cells, suggesting that non-specific electrostatic interactions have an important role in the adherence of this species.

Summary The bending characteristics of various parapulpal pins, the retention of a parapulpal pin in different core buildup materials, and the fracture resistance of pin-retained cores were investigated in an in-vitro study. In amalgam and composite cores, the use of parapulpal pins produced an increase in fracture resistance. The highest fracture resistance values were observed in amalgam cores, and the lowest fracture strength was exhibited by cores of glass ionomer cements (GICs) containing metallic particles. The different parapulpal pins and their flexural rigidity had little effect on the fracture resistance of the pin-retained cores. For extensive pin-retained cores it appears advisable to use GICs with restraint and, particularly in the case of large-scale bridge reconstructions, only after critical examination of the loading conditions.

Summary The personality traits of 66 of a sample of 70 adolescents aged 19–21 years were reexamined after 5 years by means of a personality inventory (KSP). A total of 15 subjects had intact dentitions (group I), while 13 subjects had had some fillings in their teeth since the first examination (group FI), and 38 subjects had restored dentitions at both examinations (group F). The findings of this study are in agreement with those of the earlier study of Kampe, Edman and Molin (1986). On both occasions the subjects with restored dentitions had higher scores on the Somatic Anxiety and Muscular Tension scales. The differences were more pronounced for the female subjects. With regard to muscular tension, there was a significant interactive effect, with higher values for the female subjects in group F. Individuals with high scores for the Clinical Dysfunction Index (DiII and DiIII) also had the highest scores on the Somatic Anxiety and Muscular Tension scales, thus confirming the validity of the muscle palpation. The hypothesis of a correlation between personality factors and dental-filling therapy was neither accepted nor rejected. The subjects in group F had the highest scores on both occasions on the Somatic Anxiety and Muscular Tension scales, although the subjects in group FI had the lowest scores. Further studies are required, and another 5-year follow-up study of this material could be conclusive.

Objectives: To compare the prevalence of caries between rural and urban children with unmet dental health needs who participated in the New England Children's Amalgam Trial. Methods: Baseline tooth and surface caries were clinically assessed in children from rural Maine (n = 243) and urban Boston (n = 291), who were aged 6 to 10 years, with two or more posterior carious teeth and no previous amalgam restorations. Statistical analyses used negative binomial models for primary dentition caries and zero-inflated models for permanent dentition caries. Results: Urban children had a higher mean number of carious primary surfaces (8.5 versus 7.4) and teeth (4.5 versus 3.9) than rural children. The difference remained statistically significant after adjusting for sociodemographic factors and toothbrushing frequency. In permanent dentition, urban children were approximately three times as likely to have any carious surfaces or teeth. However, rural/urban dwelling was not statistically significant in the linear analysis of caries prevalence among children with any permanent dentition caries. Covariates that were statistically significant in all models were age and number of teeth. Toothbrushing frequency was also important for permanent teeth. Conclusions: Within this population of New England children with unmet oral health needs, significant differences were apparent between rural and urban children in the extent of untreated dental decay. Results indicate that families who agree to participate in programs offering reduced cost or free dental care may present with varying amounts of dental need based on geographic location.

Objectives: Previous research shows increased dental decay among immigrants, but little is known about the oral health of the growing population of children of immigrants. We compared the children of immigrants to the children of US-born caregivers in their caries experience at enrollment and their new caries increments during the 5-year New England Children's Amalgam Trial (NECAT). Methods: NECAT recruited 283 Boston-area children aged 6 to 10 with untreated caries and offered free semiannual preventive and restorative dental care during the trial. Sociodemographic factors and caregiver immigrant status were assessed through interviews. Multivariate negative binomial models evaluated the association between caregiver immigrant status and clinically assessed carious surfaces. Results: Forty percent of these Boston-area children had immigrant caregivers. At baseline, the children of immigrants had more carious surfaces (11.5 versus 9.4, adjusted for race/ethnicity, age, gender, and caregiver smoking status). Caregiver language preference explained some of this association. Immigrant status and language preference were not associated with 5-year caries increments. Conclusions: Prevalent disparities in the unmet dental needs of the immigrants' children were quickly ameliorated during participation in NECAT. Dental initiatives that target neighborhoods and are sensitive to acculturation levels may help improve and maintain the oral health of immigrant families.

Aim: The aim of this study was to evaluate the effect of air polishing and different ultrasonic scaler inserts on dental fillings, such as amalgam, composite and porcelain. Materials and methods: This study was performed on amalgam, composite and porcelain samples. The surfaces of the samples were exposed to different type of piezoelectric ultrasonic scaler inserts and air-abrasive unit. The scaler inserts were Instrument A, Instrument PS and PI. The roughness of the surfaces of each sample were measured with a profilometer and observed by stereomicroscope. Results: The stereomicroscopic images and profilometric values showed that Instrument A and PS resulted in rough surfaces, such as chips, nicks and scratches on the amalgam, composite and porcelain surfaces. The Instrument PI roughened the amalgam surface, but it did not roughen the porcelain or composite surfaces. The profilometric measurements (Ra) showed that the roughness of the surfaces depending on air polishing was less than the ultrasonically scaled surfaces. Conclusion: The wrong tip applications during dental scaling procedure cause roughness, such as scratches, nicks or chips, not only on the teeth surfaces but also on the filling materials. Thus, dental scaling procedure on the restorations should be performed carefully and the roughness sites on the restorations have to be re-polished after scaling to prevent plaque accumulation.

Nightguard vital bleaching with 10% carbamide peroxide was shown to have some minor effects on certain brands of amalgam mainly related to mercury release. However, in this case report, amalgam staining of the bleaching tray was detected in correspondence of the left and right first upper molars following tooth whitening for a week. These teeth presented MOD amalgam fillings with superficial chipping at the cavosurface margins. The same phenomena did not occur in the mouth with other amalgam intracoronal restorations not showing marginal defects. No decay or discoloration was noted around the amalgam fillings both in the upper and lower teeth. At the 1-week recall visit, patient was recommended to avoid the bleaching gel application in the maxillary first molar teeth. The existing fillings were replaced with composite resin restorations after a 2-week elapse time. CLINICAL SIGNIFICANCE The unusual amalgam staining of the bleaching tray suggests that amalgam restorations with defective cavosurface margins should be monitored during the tooth whitening therapy. Alternatively, their replacement should be considered prior to bleaching. (J Esthet Restor Dent 19:208‐213, 2007)

Aim To investigate the attitudes towards and use of rubber dam by Irish general dental practitioners. Methodology A pre-piloted questionnaire was distributed amongst a group of 600 dentists randomly selected from the Irish Register of Dentists. Replies from dentists working in specialist practice or the hospital dental service were excluded. Dentists were surveyed in relation to their use of rubber dam during a variety of operative and root canal treatments, as well as their attitudes to the use of rubber dam in dental practice. Results A total of 300 replies were considered from a total of 324 that were received. Seventy-seven per cent of respondents (n ¼ 231) worked in general dental practice and 23% (n ¼ 69) worked in the Irish Health Board/Community Dental Service. Rubber dam was ‘never’ used by 77% of respondents (n ¼ 228) when placing amalgam restorations in posterior teeth, 52% (n ¼ 147) when placing composite restorations in posterior teeth, and 59% (n ¼ 177) when placing composite restorations in anterior teeth. Rubber dam was ‘never’ used by 39% of respondents (n ¼ 114) when performing root canal treatment on anterior teeth; 32% (n ¼ 84) when performing root canal treatment on premolar teeth; and 26% (n ¼ 51) when performing root canal treatment on molar teeth. Fiftyseven per cent (n ¼ 171) considered rubber dam ‘cumbersome and difficult to apply’, and 41% (n ¼ 123) considered throat pack ‘as good a prevention against inhalation of endodontic instruments as rubber dam’. Conclusions Whilst rubber dam is used more frequently for root canal treatment than operative treatment, its use is limited. This presents quality issues, as well as medico-legal and safety concerns for both the profession and patients.

Objective: This study compares the quality of class I restorations made with the atraumatic restorative treatment (ART) technique and conventional class I amalgam restorations. Methods: The study was carried out among secondary school students in Mzuzu, Malawi. First-year students in 1987 who needed at least two class I restorations were selected. Based on a split-mouth design, each participant received both ART and conventional restorations. The 89 pairs of class I cavities were divided randomly into two groups, since two different cermet ionomer cement (CIC) filling materials were used. Impressions of the restorations and subsequent models were made shortly after restoration, after six months, one year, two years, and three years. The quality of the restorations was determined on the models following the US Public Health Service criteria. Bulk fracture, contour, marginal integrity, and surface texture of the restorations were recorded and evaluated separately. Survival rates were determined by the resultant score of all criteria. Results: Though conventional amalgam restorations performed better on all criteria, this difference was significant only for the contour criterion. The survival rates of ART restorations after three years (81.0%) were lower than those of amalgam restorations (90.4%) (P=.067). Conclusions: The quality of ART class I restorations is competitive with that of conventional amalgam restorations.

Blood lymphocytes from 20 patients with oral contact lesions to dental amalgam and 10 healthy individuals were analyzed for HgCl2-induced proliferation in vitro, using both a modified assay and a conventional assay. The release of interferon-gamma (IFN-gamma) was measured in cell supernatants. Six patients displayed positive reactions in patch tests to mercuric compounds. No significant differences were recorded in HgCl2-induced proliferation in cells from patients and controls, since only few in the whole material responded to submitogenic concentrations. IFN-gamma was detectable in cell supernatants from some patients but also from controls and is not predictive of mercury allergy. Neither the phenotypes of peripheral lymphocyte subsets, the frequency of circulating cells expressing the interleukin-2 (IL-2) receptor, spontaneous lymphocyte proliferation nor concentrations of serum interleukin-6 differed between patient and control samples. In contrast to what has been claimed before, we did not find any evidence for specific in vitro lymphocyte reactivity in patients with oral contact lesions.

Tan L, Chen NN, Poon CY, Wong HB. Survival of root filled cracked teeth in a tertiary institution. International Endodontic Journal, 39, 886‐889, 2006. Aim To assess the survival rate of root filled cracked teeth over a 2-year period in a tertiary institute. Methodology Forty-nine patients who had root canal treatment completed on their cracked teeth at the National Dental Centre (Singapore) were recalled for a 2-year review. Collected review data included presence of periodontal pocketing, sinus tract and swelling associated with the teeth. The date of extraction was noted if a tooth was missing at review. Pretreatment data collected were number, extent and location of crack, presence of periodontal pocketing, patients’ age and gender, location of cracked teeth, type of teeth and presence of terminal cracked tooth. Results Fifty teeth in 49 patients were included. The Kaplan‐Meier estimate of 2-year survival rate was 85.5% (95% confidence interval: 75.5‐95.5). Cracked teeth which were the terminal teeth in the dental arch (RR ¼ 4.9, 95% CI: 1.2‐2.0, P ¼ 0.04), teeth with pre-root filling periodontal pocketing (RR ¼ 4.9, 95% CI: 1.2‐2.0, P ¼ 0.04) and teeth with multiple cracks (RR ¼ ¥, 95% CI: 1.9‐¥, P ¼ 0.01) were more likely to be extracted. Conclusions Within the limitations of this study, multiple cracks, terminal teeth and pre-root filling pocketing were significant prognostic factors for the survival of root filled cracked teeth.

Objectives: To identify histological features that distinguish amalgam-associated oral lichenoid reactions (AAOLR) from oral lichen planus (OLP). Methods: Oral pathologists provided their opinion as to the possibility of distinguishing AAOLR and OLP histologically, the features important in distinguishing AAOLR from OLP and the diagnosis of 12 AAOLR and 12 OLP cases including the features that drew them to their conclusion. Results: There was considerable variation between pathologists in their ability to distinguish the AAOLR and OLP cases. The sensitivity and specificity for histological diagnosis were 40% and 32% respectively. There were four features that were used most commonly to discriminate between AAOLR and OLP: an inflammatory infiltrate located deep to superficial infiltrate in some or all areas; a focal perivascular infiltrate; plasma cells in the connective tissue and neutrophils in the connective tissue. Each was independently predictive of AAOLR or OLP (P

Objective: To assist clinical decision making for an individual patient or on a community level, this study was done to determine the differences in costs and effectiveness of large amalgams and crowns over 5 and 10 years when catastrophic subsequent treatment (root canal therapy or extraction) was the outcome. Methods: Administrative data for patients seen at the University of Iowa, College of Dentistry for 1,735 large amalgam and crown restorations in 1987 or 1988 were used. Annual costs and effectiveness values were calculated. Costs of initial treatment (large amalgam or crown), and future treatments were determined, averaged and discounted. The effectiveness measure was defined as the number of years a tooth remained in a state free of catastrophic subsequent treatment. Years free of catastrophic treatment were averaged, and discounted. The years free of catastrophic treatment accounted for individuals who dropped out or withdrew from the study. Results: Teeth with crowns had higher effectiveness values at a much higher cost than teeth restored with large amalgams. The cost of an addition year free of catastrophic treatment for crowns was $1,088.41 at 5 years and $500.10 at 10 years. Teeth in women had more favorable cost-effectiveness ratios than those in men, and teeth in the maxillary arch had more favorable cost-effectiveness ratios than teeth in the mandibular arch. Conclusions: Neither the large amalgam or crown restoration had both the lowest cost and the highest effectiveness. The higher incremental cost-effectiveness ratio for crowns should be considered when making treatment decisions between large amalgam and crown restorations.

Purpose: The aim of this study was to investigate the current teaching of posterior composite resin restorations to undergraduate dental students in Ireland and the United Kingdom (UK). The investigation was a follow-up to a survey undertaken in 1997. Materials and methods: A questionnaire was distributed by e-mail to the Heads of Departments of Restorative Dentistry/Units of Operative Dentistry in each of the 15 dental schools with undergraduate dental degree programmes in Ireland and the UK. The questionnaire sought information relating to the teaching of posterior composite resin restorations in each dental school. Results: Fifteen completed questionnaires were returned (response rate = 100%). All schools (n = 15) taught the placement of composite resin restorations in occlusal cavities, 14 schools taught composite resin placement in two-surface occlusoproximal cavities and nine schools taught composite resin placement in three-surface occlusoproximal cavities. Respondents anticipated that the amount of preclinical teaching of posterior composite resin placement will increase twofold over the next 5 years, whilst the corresponding teaching of amalgam will fall to two-thirds its current level. Variation was found between dental schools in the teaching of the principles of cavity design, contraindications to placement, indications for lining and basing techniques, matrix and wedging techniques, and the use of curing lights. Conclusions: The amount of teaching of posterior composite resin restorations in undergraduate dental schools in Ireland and the UK has increased since the time of a previous survey in 1997. Composite resin may soon equal or overtake amalgam as the material of choice when restoring posterior cavities in Irish and UK dental schools. There was, however, much variation in the nature and extent of the teaching and the techniques taught.

The purpose of this study was to determine any inadvertent effects of the neodymium: yttrium-aluminium-garnet (Nd:YAG) laser, air-abrasion, and ortho-phosphoric acid on some conventionally used dental filling materials [amalgam, composite resin, compomer, glass-ionomer cement (GIC), and ceromer], when they were used for purposes of margin etching and assessed according to standard enamel etching parameters using a total of five fillings. The surfaces of the filling materials were polished. One sample from each material group was exposed to laser (at 0.75 J, 15 pps) and air abrasion (with Al-oxide powder, 60 psi) for 2 s and to the 37% ortho-phosphoric acid for 60 s. The exposed materials were examined under Scanning Electron Microscopy (SEM). After laser treatment most specimens showed recrystallized areas, the GIC surface being the most affected. There were some pores and cavities on the amalgam surface following laser treatment. The abraded surfaces showed mechanical abrasions. The acid etchant showed the least effect. During the application of laser or air-abrasion, the adjacent tooth or filling surface must be protected or the dentist must be careful.

Background: There are few Australian data on the reasons for placement and replacement of restorations, and the extent to which these are carried out in general practice. Methods: A survey was carried out of approximately 100 consecutive restorations placed by each of 28 general dental practitioners. The data were coded and statistically analyzed for various associations. Results: Resin composite was used twice as frequently as amalgam as a restorative material, and nearly four times as often as glass-ionomer cement. Secondary caries was the principal reason for replacing restorations, affecting predominantly amalgam restorations in Class I and Class V cavities. Teeth restored with amalgam fractured nearly twice as often as teeth restored with resin composite. The average ages of amalgam, resin composite and glassionomers at replacement were 13.6, 7.1 and 5.7 years respectively. Conclusions: Amalgam has the longest clinical service life, but is associated with more tooth fracture. Secondary caries is the main reason for replacing restorations. The anti-cariogenic effect of glass-ionomer cement is equivocal.

– Objectives: The extent to which substances released from dental materials cause adverse health effects and whether removal of dental materials results in improvement of health is a matter of dispute. The aim of the study was to investigate changes in the intensity of subjective symptoms after replacement of dental materials in patients referred for adverse reactions related to dental materials, and to compare the profiles of symptoms with those found in the general population. Methods: Information was obtained from 142 patients referred to the Dental Biomaterials Adverse Reaction Unit in Bergen, Norway. At the time of examination, all patients completed a questionnaire regarding a range of subjective symptoms. A follow-up questionnaire was sent to all patients 1 to 2 years later. Similar questionnaires were sent to a reference group of 800 persons drawn from the general population. Results: The follow-up questionnaires were completed and returned by 84 patients, and 441 persons in the reference group. The patient group presented higher symptom indices than the reference group (P

Background: A number of reports exist on the side effects of materials used to restore teeth. Most of the cases involve local allergy reactions, but also skin lesions are described. Few cases are described where both local effects on the mucosa and skin lesions distant to the oral cavity are caused by amalgam. Result: The case presented indicates that the release of mercury from amalgam fillings is able to induce hypersensitivity reactions resulting in soft-tissue changes in the gingiva, buccal mucosa, tongue and on the skin of the back of the hands.

Background: This study aimed to determine the reasons for dentists’ choice of materials, in particular amalgam and resin composite, in Australia. Method: A questionnaire was developed to elicit this information. The names and addresses of 1000 dentists in Australia were selected at random. The questionnaire was mailed to these dentists with an explanatory letter and reply-paid envelope. Results: A total of 560 replies were received. Regarding choice of material, 99 per cent of respondents cited clinical indication as an influencing factor, although patients’ aesthetic demands (99 per cent of respondents), patients’ wish (96 per cent), patients’ financial situation (82 per cent), and lecturers’ suggestions (72 per cent) were also reported to influence respondents’ choice of materials. Twelve per cent of respondents used composite ‘always’, 29 per cent ‘often’, 32 per cent ‘sometimes’, 23 per cent ‘seldom’ and 4 per cent ‘never’ in extensive loadbearing cavities in molar teeth. For composite restorations in posterior teeth, 84 per cent ‘always’, ‘often’ or ‘sometimes’ used the total etch technique, 84 per cent used a thick glass-ionomer layer and 36 per cent never used rubber dam. Fifty-nine per cent of respondents reported a decreased use of amalgam over the previous five years. Sixty-eight per cent of respondents agreed with the statement ‘discontinuation of amalgam restricts a dentist’s ability to adequately treat patients’. Seventy-five per cent considered that the growth in the use of composites increased the total cost of oral health care. Conclusions: Of the respondents from Australia 73 per cent place large composite restorations in molar teeth and their choice of material is influenced greatly by clinical indications, and patients’ aesthetic demands.

This study evaluated the corrosion behaviour of two high copper dental amalgam alloys [Dispersalloy (Dentsply-Caulk) and Tytin (Kerr)] in different electrolytes. Amalgam specimens were prepared, coupled to a copper wire, cemented into glass tubes and polished to a 600-grit finish. A corrosion cell was prepared using a carbon counter-electrode, a standard calomel electrode as the reference and amalgam as the working electrode. The alloys were tested in the following mediums at 37 degrees C: (i) artificial saliva based on Fusayama's solution (FS), (ii) artificial saliva with citric acid adjusted to pH 4.0 (FC) and (iii) 1% sodium chloride solution (SC). Corrosion potentials (E(corr)) and corrosion rates (I(corr)) were determined using potentiostatic and impedance spectroscopy methods. Data was subjected to anova/Scheffe's post hoc test at 0.05 significance level. For both alloys, the corrosion potential in FS was significantly greater than in SC. Corrosion potential of Tytin in FS and SC was also significantly greater than in FC. The corrosion rate of Dispersalloy in FC was significantly greater than in FS and SC. For Tytin, corrosion rate in SC was significantly greater than in FS and FC. Although no significant difference in corrosion potential/rate was observed between the alloys when tested in FS, significant differences were observed when electrochemical testing was carried out in FC and SC. The corrosion behaviour of high copper amalgam alloys are both material and environment dependent. Certain food substances may increase the corrosion of high copper amalgams.

Background In an in vitro study, the surface wear on cervical restorations and adjacent enamel and root cementum caused by different tooth-cleaning methods in simulated long-term therapy was investigated. Methods Cervical restorations of amalgam (Oralloy), modified composite resin (Dyract), glass-ionomer cement (ChemFill Superior), and composite (Tetric) were instrumented by POL (polishing), CUR+POL (curette and polishing), US+POL (ultrasonic device with polishing) and the polishing agents Cleanic and Proxyt in a computer-controlled test bench. Treatment time corresponding to a real-time period of 5 or 10 years. Substance loss from instrumented surfaces was measured with a digital gauge. A three-way anova was used in the statistical evaluation. Results The results showed that POL led to slight substance loss, which was greater using Cleanic (27 microm) than Proxyt (5 microm). CUR+POL produced a significantly greater substance loss than did US+POL, with 186 microm versus 35 microm on glass-ionomer cement, respectively, and 123 microm versus 18 microm, respectively, on root cementum, followed by composite (111 microm versus 27 microm, respectively), polyacid modified composite resin/compomer (89 microm versus 36 microm), amalgam (75 microm versus 19 microm), and enamel (32 microm versus 23 microm). Conclusions As opposed to the use of US+POL or POL, substance loss on cervical restorations and especially root cementum must be expected to result from tooth-cleaning during long-term maintenance treatment using CUR+POL.

A continuous flow system was developed to evaluate the adhesion of Streptococcus mutans ATCC 25175 to filling materials (Ariston, Tetric, Dyract, Compoglass, Vitremer, Aqua Ionofil, Ketac Fil, amalgam, Galloy and ceramics as controls). Streptococcus mutans was added to saliva-coated test specimens, and a nutrient broth permanently supplied over a time period of 48 h and then the weight of plaque, the number and viability of the bacteria adhering to the materials were determined. The weights of artificial plaque on all filling materials tested were higher than those on ceramics, the highest values were measured on the glass-ionomers. The amount of plaque correlates with the surface roughness, whereas there was no correlation of the surface roughness with the number of colony-forming units (CFU) of S. mutans. The CFU of adhering S. mutans also depends on the viability of the bacteria. The plaque on Ketac Fil contained a high number of viable bacteria. The fluorides of glass-ionomers do not efficiently prevent the attachment and the viability of S. mutans.

Background: To determine whether clinical examinations and periapical radiographs provide sufficient information to assess the cause of pulp and periapical diseases, the status of teeth when restored and their further treatment needs. Other aims were to determine whether restorations should be removed prior to commencing endodontic treatment, and whether the type and longevity of restorations were related to the presence of disease. Methods: Information was collected regarding 245 restored teeth from 220 consecutive patients referred for endodontic treatment. Teeth were examined before and after the restorations were removed and the findings were compared. Results: Pre-operative examination revealed 47 (19.2 per cent) teeth had caries, 57 (23.3 per cent) had cracks and 96 (39.2 per cent) had marginal breakdown. After restoration removal, the figures were 211 (86.1 per cent), 147 (60 per cent), and 244 (99.6 per cent) respectively. Almost all teeth (93 per cent) had more than one of these factors and periapical radiographs were unreliable indicators of their presence. There was only a 56.1 per cent chance (with 95 per cent Confidence Interval) of finding caries, cracks or marginal breakdown prior to restoration removal. Composite resins were more often associated with early onset and rapid progression of pulp diseases. Conclusions: All restorations should be removed prior to endodontic treatment in order to remove the common factors that may have caused the pulp and periapical disease, and to assess the tooth’s prognosis and future treatment needs.

The short-term tissue responses to two potential root-end filling materials, a light-cured glass ionomer cement (Vitrebond) and a reinforced zinc oxide-eugenol cement (Kalzinol), were compared with that to amalgam using a previously devised experimental model. In 24 premolar teeth of beagle dogs (47 roots), a collection of endodontic pathogenic bacteria was first inoculated into the root canals to induce periradicular lesions. On each root, an apicoectomy was performed and root-end cavities prepared to receive fillings of each material. The teeth and surrounding jaw were removed after 2 weeks (23 roots) and 1 week (24 roots); they were then prepared for histological examination. The tissue response to amalgam fillings after 2 weeks and 1 week was marked by moderate or severe inflammation on all roots, and extended toor = 0.5 mm or0.5 mm in 15 out of 16 roots. In contrast, after 2 weeks, the majority of roots filled with Kalzinol showed little or moderate inflammation, while the tissue response to Vitrebond was the best of the three materials, and was also the least extensive. After 1 week, the overall best tissue response was with Vitrebond, followed by Kalzinol. The differences between materials for both time periods with either none or few inflammatory cells when compared with that with either moderate or severe inflammation were not statistically significant (P0.02). However, the differences between materials for both time periods with no inflammation or inflammation extending0.2 mm when compared with that with inflammation extending0.2 mm (or = 0.5 mm or0.5 mm) were statistically significant (P0.01). Apart from amalgam, in which healing was marked by the persistence of a localized focus of inflammation adjacent to the root-end filling, even though there were intersample variations, there was little overall difference in the temporal and qualitative healing response to Vitrebond and Kalzinol. Both Vitrebond and Kalzinol have potential as root-end filling materials, as the tissue response was considerably more favourable than that to amalgam even in the short-term.

Tooth bleaching is a popular procedure in modern aesthetic dentistry. Bleaching agents may affect amalgam restorations by altering the release of mercury. The aim of this study was to explore the effect of biofilm-coated amalgam restorations on the release of mercury in the presence of carbamide peroxide. Samples of SDI and Valliant amalgams were submerged for either 14 days or 7 months in buffered KCl after which they were coated with saliva, bacteria, and polysaccharides. The samples were exposed to 10% carbamide peroxide (CP) for 24 h. The amount of mercury released was examined for 120 h. Results showed that most of mercury release occurred within the first 24 h, after which the release rate decreased sharply. After 120 h the release of mercury from the tested samples was minimal and similar to the control group. The presence of biofilm coating on the amalgam samples did not induce the release of mercury but tended to reduce mercury release into the surrounding environment. CP induces the release of mercury from amalgam samples. However, the presence of biofilm did not prevent large amounts of mercury release from amalgam coated with biofilms and exposed to CP. This study indicates that dental biofilm may retard the release of mercury from amalgam restorations.

The purpose of this study was to examine the association of dental materials with oral lichen planus (OLP) and, particularly, the effects of amalgam, amalgam corrosion status, gold and dissimilar metals in continuous contact. A case-control study was performed with 43 OLP cases from the Oral Medicine Clinic at the School of Dentistry, University of Washington and 78 controls from a general dental care-screening clinic, also at the School of Dentistry, University of Washington. Health histories and oral examinations were obtained. Current metal or metal-based restorations were charted, along with corrosion status of amalgams and the presence of dissimilar metals in continuous contact. Adjusted odds ratios (ORs) and 95% confidence intervals for the following potential risk factors were found to be: (1) number of teeth with amalgam, OR = 1.02 (0.92, 1.13); (2) total surfaces of amalgam, OR = 0.96 (0.92, 1.0); (3) number of teeth with gold, OR = 1.12 (0.95, 1.31); (4) mean amalgam corrosion score, OR = 5.74 (2.34, 14.1); (5) presence of dissimilar metals in contact (per quadrant), OR = 1.25 (0.81, 1.92). These findings suggest that although the presence of amalgam or gold themselves is not associated with increased risk of OLP, corrosion of amalgams and the presence of a 'galvanic effect' from dissimilar dental materials in continuous contact (bimetallism) are associated with an increased risk of OLP.

A 61-year-old woman presented with a 2-year history of an abnormal erythematous swelling on the upper lip and cheek. Upon examination there were no other physical findings. Histological examination found discreet sarcoidal granulomas in the lower dermis. Routine laboratory studies, chest radiographs and pulmonary functions were all normal. Clinical presentation and histological findings were, therefore, compatible with the diagnosis of orofacial granulomatosis (OFG). The patient was patch tested with an extended standard series that included metal-salt, dental prosthesis, bakery and corticosteroids series. The patch test was positive (score ++) after 48 and 72 h for mercury in the metal-salt and dental prosthesis series. During the past decade the patient had received amalgam fillings of several dental cavities, including one adjacent to the swollen cheek. The unilateral localization of the soft tissue swelling adjacent to the amalgam tooth fillings, along with the positive patch test for mercury, raised the possibility that the OFG was part of a delayed hypersensitive reaction to the fillings. The patient therefore underwent a total amalgam replacement procedure; complete disappearance of the swelling overlying the right cheek was observed within 7 weeks and the swelling of the upper lip subsided completely within 6 months. We propose that mercury in amalgam tooth fillings is another cause of OFG and suggest appropriate patch testing in patients who do not have an apparent cause of OFG.