Amalgam Restorations Research Articles

Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational Cross-Sectional Study With Meta-Analysis.

This web-based survey, conducted across multiple countries, sought to explore the factors that impact the decision-making of clinicians when it comes to managing defective direct restorations. A survey consisting of 14 questions was sent out to dentists in 21 countries through various online platforms. The survey consisted of two sections. The first contained five questions about demographic information, while the second involved eight clinical scenarios. In the second part, participants were tasked with deciding whether to repair or replace defective composite and amalgam restorations. Three thousand six hundred eighty dental practitioners completed the survey. For composite restorations, repair was preferred in scenarios like partial loss or fracture (RR:0.72; 95% CI: 0.58, 0.89; p = 0.002), whereas replacement was favored for secondary caries (RR:2.43; 95% CI: 1.87, 3.16; p < 0.001) and open/defective margins (RR:3.93; 95% CI: 2.68, 5.76;p < 0.001). Amalgam restorations were mostly replaced across all scenarios. The main factors influencing decision-making were caries risk, restoration size, and patient oral hygiene. Substantial heterogeneity was observed across countries. This study underscores the complexity of the decision-making process and the need for evidence-based guidelines to inform clinicians' decisions regarding restoration management. Patient-level factors predominantly influence decision-making, emphasizing the need for individualized approaches. The study reveals that the material type in the original restoration is a critical determinant, with composite restorations being repaired in specific scenarios, while amalgam restorations are consistently replaced across different countries. Key patient and tooth-level factors, such as high caries risk, poor oral hygiene, and restoration size, significantly impact clinicians' decisions, often favoring replacement over repair. These findings underscore the necessity for evidence-based guidelines to assist clinicians in making informed choices, ultimately enhancing the quality of patient care.

Effects of Finishing on Surface Roughness of Four Different Glass-Ionomer Cements and One Alkasite: In Vitro Investigation over Time Using Aging Simulation

In 2017, Europe implemented a ban on amalgam restorations for children aged &lt;15 years and for pregnant/breastfeeding women, highlighting the need for alternative filling materials exhibiting less surface roughness and enhanced longevity. This in vitro study aimed to examine the surface roughness variations of five amalgam-replacement materials across three time points and using six finishing methods: (1) no finishing (control), (2) Arkansas burs, (3) diamond burs, (4) tungsten carbide burs, (5) SofLex discs in descending grit size, and (6) coarse SofLex discs combined with silicone polishing. We prepared 960 samples. Each material group, i.e., Cention Forte (CNF), DeltaFil (DLF), Ketac Universal (KTU), IonoStar Molar (ISM), and Equia Forte HT (EQF), comprised 60 samples (n = 10 per finishing method) created using standardized 3D-printed metal molds. Surface roughness (Sa) was measured immediately after finishing, after 30 days of storage in distilled water, and after thermocycling (5000 cycles) using a non-contact profilometer. The results indicate that conventional and hybrid glass-ionomer cements have smoother surfaces than high-viscosity GICs. The DLF and CNF groups exhibited stable outcomes. These findings underscore the importance of selecting appropriate finishing methods based on the restorative material to minimize surface roughness.

Advancing Diabetic Dental Restorations: A Comparative Analysis of Alveolar Bone Loss in Class II Composite Resin Versus Amalgam Fillings.

Introduction This study evaluated the impact of Class II composite resin and amalgam restorations on alveolar bone loss in diabetic patients, a population more susceptible to periodontal complications. The main objective was to determine whether the choice of restorative material impacts periodontal health, providing insights to optimize dental care for this high-risk group. Materials and methods This observational, comparative. cross-sectional study included 64 diabetic patients, divided into two groups based on their Class II restorations. Group 1 had 32 patients with composite resin restorations, while Group 2 comprised 32 patients with amalgam restorations. Both groups were matched for age and diabetes duration to ensure comparability. Periodontal health, specifically alveolar bone loss, was assessed through clinical and radiographic evaluations. The study analyzed the impact of the two materials on alveolar bone levels. Results Data from 64 diabetic patients (32 in Group 1 and 32 in Group 2) were statistically analyzed using PASW Statistics for Windows, Version 18.0 (Released 2009; SPSS Inc., Chicago, United States). Three statistical tests, descriptive statistics, two-sample t-test, and analysis of covariance (ANCOVA), were used. The results showed significant differences between the two groups, with composite resin restorations linked to greater alveolar bone loss. Conclusion The choice of restorative material significantly influences periodontal health in diabetic patients. Composite resin restorations were associated with a higher risk of alveolar bone loss and periodontal disease, emphasizing the need for careful material selection and regular periodontal monitoring in diabetic patients.

Implementation of machine learning models as a quantitative evaluation tool for preclinical studies in dental education.

Objective, valid, and reliable evaluations are needed in order to develop haptic skills in dental education. The aim of this study is to investigate the validity and reliability of the machine learning method in evaluating the haptic skills of dentistry students. One-hundred fifty 6th semester dental students have performed Class II amalgam (C2A) and composite resin restorations (C2CR), in which all stages were evaluated with Direct Observation Practical Skills forms. The final phase was graded by three trainers and supervisors separately. Standard photographs of the restorations in the final stage were taken from different angles in a special setup and transferred to the Python program which utilized the Structural Similarity algorithm to calculate both the quantitative (numerical) and qualitative (visual) differences of each restoration. The validity and reliability analyses of inter-examiner evaluation were tested by Cronbach's Alpha and Kappa statistics (p=0.05). The intra-examiner reliability between Structural Similarity Index (SSIM) and examiners was found highly reliable in both C2A (α=0.961) and C2CR (α=0.856). The compatibility of final grades given by SSIM (53.07) and examiners (56.85) was statistically insignificant (p>0.05). A significant difference was found between the examiners and SSIM when grading the occlusal surfaces in C2A and on the palatal surfaces of C2CR (p<0.05). The concordance of observer assessments was found almost perfect in C2A (κ=0.806), and acceptable in C2CR (κ=0.769). Although deep machine learning is a promising tool in the evaluation of haptic skills, further improvement and alignments are required for fully objective and reliable validation in all cases of dental training in restorative dentistry.

Determining the Failure Rate of Direct Restorations-Chart Review versus Electronic Health Record Reports.

Amalgam and composite restorations are used to treat minor dental issues. University of Michigan, School of Dentistry Electronic Health Record (EHR) reports show a 2.31% failure rate for amalgam and 1.14% for composite. Our study aims to determine the true failure rates through manual EHR chart reviews. Patient data from the University of Michigan School of Dentistry were utilized-216 amalgam restorations from 2020 to 2022 and 350 composite restorations in 2021 were searched. We defined failure and retreatment as replacing a restoration with the same material and failure and alternate treatment as replacing restoration with an alternative treatment within one year. The failure rate refers to a combination of replacement with the same and alternative treatment material within one year. For Amalgam: 1.85% failed and were retreated; 7.87% failed and were received an alternate treatment. Composite: 9.71% failed and retreated; 2.86% failed and received alternate treatment. In total anterior composite: 10.5% retreated, 2.6% failed; posterior composite: 9.1% retreated, 3.0% failed. Our study revealed higher restoration failure rates than the reports extracted in the EHR. This highlights the need to foster a culture of precise documentation to align EHR reports with hand-search findings.

Evaluation of alveolar bone loss among diabetic patients with class II amalgam restorations.

The relationship between Class II amalgam restorations and alveolar bone loss among diabetic and non-diabetic patients is evaluated at the Faculty of Dentistry, Najran University, KSA. Hence, we compared type 2 diabetic (n = 32) and non-diabetic patients (n=32) using clinical assessments and imaging techniques. Parameters such as bone loss rate, extent, age, and periodontal condition (plaque index and Gingival Index) were analyzed. Analysis of data shows that diabetic patients on average have higher bone loss.

Survival Rates of Amalgam and Composite Resin Restorations from Big Data Real-Life Databases in the Era of Restricted Dental Mercury Use.

Tooth decay, also known as caries, is a significant medical problem that harms teeth. Treatment is based on the removal of the carious material and then filling the cavity left in the tooth, most commonly with amalgam or composite resin. The consequences of filling failure include repeating the filling or performing another treatment such as a root canal or extraction. Dental amalgam contains mercury, and there is a global effort to reduce its use. However, no consensus has been reached regarding whether amalgam or composite resin materials are more durable, and which is the best restorative material, when using randomized clinical trials. To determine which material is superior, we performed a retrospective cohort study using a large database where the members of 58 dental clinics with 440 dental units were treated. The number of failures of the amalgam compared to composite resin restorations between 2014 and 2021 were compared. Our data included information from over 650,000 patients. Between 2014-2021, 260,905 patients were treated. In total, 19,692 out of the first 113,281 amalgam restorations failed (17.49%), whereas significantly fewer composite restorations failed (11.98%) with 65,943 out of 555,671. This study indicates that composite is superior to amalgam and therefore it is reasonable to cease using mercury-containing amalgam.

Repair versus replacement of defective direct dental restorations: A multinational cross-sectional study with meta-analysis

ObjectivesWhen dental practitioners encounter a defective restoration, they are faced with a crucial decision whether to repair or replace it. This study aims to explore international preferences for repair procedures and the clinical steps taken during the repair process. MethodAn 11-question survey was distributed to dentists across 21 countries via different platforms. The survey comprised two sections: the first included five questions aimed at gathering demographic information, while the second consisted of six questions focusing on participants' practices related to the repair of composite or amalgam restorations A meta-analysis was employed to ascertain the pooled odds ratio of repairing versus replacement. The statistical analysis was carried out using the RevMan 5.3 program and forest plots were generated using the same program to visualize the results. ResultsThe survey was completed by 3680 dental practitioners. The results indicated a strong tendency to repair defective composite restorations (OR: 14.23; 95 % CI: 7.40, 27.35, p < 0.001). In terms of amalgam, there was a significant tendency to replace the restorations (OR: 0.19; 95 % CI: 0.12, 0.30, p < 0.001). When repairing restorations, the most common protocols were etching with orthophosphoric acid and creating an enamel bevel, regardless of the restorative material used. ConclusionThe findings of this study indicate that there exists a knowledge gap among dental practitioners regarding restoration repair. It is imperative that dental practitioners receive proper education and training on restoration repair, to ensure the usage of adequate protocols and restoration survival. Clinical significanceA significant portion of dental practitioners lack the necessary knowledge and education required for the repair of restorations. Therefore, it is imperative to establish guidelines aimed at enhancing the management of defective restorations, along with protocols for clinical interventions. This includes the incorporation of proper courses in undergraduate, graduate, and continuing education programs.

Managing failed vital pulp therapies in mature permanent teeth in a retrospective cohort study, with success and survival rates of managing protocols

Despite advancements in vital pulp therapy (VPT), a subset of cases fails to achieve desired outcomes. This study based on a previous large-scale cohort study involving 1257 VPT-treated teeth, aiming to describe the demographic data and clinical characteristics of all failed cases and their management protocols. Clinical records/images of 105 failed cases treated by a single endodontist (2011–2022) were examined, including 10 extracted teeth. Asymptomatic cases with PDL widening received no intervention, while others underwent management protocols, including (selective) RCT and (tampon) re-VPT. These retreatments were assessed for success (defined as radiographic evidence of healing) and survival (characterized by the retention/function of the treated tooth) using Kaplan–Meier analysis. While 51.4% of all initial failures were diagnosed due to symptoms, 48.6% were symptom-free. Notably, failed cases with symptomatic irreversible pulpitis, and apical periodontitis/widened PDL before initial treatment significantly outnumbered asymptomatic cases and normal PDL, respectively (P = 0.001). Moreover, most of the initial failures were observed in teeth with composite resin rather than amalgam restorations (P = 0.002). The success and survival rates for the management protocols were 91.78% and 95.79%, respectively, over an average follow-up period of 36.94 (± 23.30) months. RCT and re-VPT procedures provide successful outcomes for managing unsuccessful VPTs.

Health complaints before and at one and five years after removal of dental amalgam restorations - data from a prospective cohort study in Norway.

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. 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. 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. 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.

Radiofrequency-Induced Heating of Amalgam Restorations and Dental Implants during 1.5T Magnetic Resonance Imaging.

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.

Effect of Polishing and Universal Bonding Application on Mercury Release from Aged Amalgam after Exposure to Bleaching Agents.

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<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.

Dead Men Do Even Tell Filled Tales

Background: Dental identification of deceased individual is a core task in the forensic dentistry. The accurate recording of clinical procedures has become more important over the time because of the increasing trends of lawsuits worldwide. Advances in imaging, root canal anatomy and restorative materials have been consistently emerging in present research and practice. Hence, the purpose of this paper is to provide an update on interrelationship between restorative dentistry and forensic personal identification.Aim: To observe the effects of predetermined incineration temperatures (400 and 800) on unrestored and restored teeth with different restorative materials, and its effect on length of tooth and volume of the pulp under Stereomicroscope and CBCT.Materials and Methods: 48 extracted premolar teeth were divided into 2 groups based on predetermined temperatures and subdivided into 4 subgroups based on restorative material used. Subgroup i- Unrestored teeth, Subgroup ii- class I Amalgam restoration, Subgroup iii- class I Amalgomer restoration and Subgroup iv- class I Cention restoration. The Antemortem and postmortem records were compared using Stereomicroscope and CBCT.Results: Teeth exposed to incineration at different temperatures will be analyzed under Stereomicroscope and CBCT.

Evaluation of Knowledge and Attitude of Yazd Dental Students in Connection with the Training of Posterior Teeth Restoration with Composite in 2023

Introduction: Today, composite resins are a suitable choice for tooth restoration, which in relation to posterior teeth, the most important limitations are marginal leakage, secondary decay, poor load bearing capacity, high wear and inability to restore contact. The durability of posterior restorations especially class II restorations is less compared to amalgam restorations. This has been affected by various factors such as polymerization shrinkage, thermal expansion coefficient and abrasion resistance that limits the durability of the posterior composite. Methods: The present study was a cross-sectional descriptive study, which 68 final year dental students of School of Dentistry of Shahid Sadoughi University of Medical Sciences in Yazd City were selected by census and their attitude and awareness were studied using a valid and reliable questionnaire containing demographic characteristics and attitude as well as awareness questions. All the data were analyzed in SPSS 16 statistical software. Likert scale was used to measure awareness and attitude. Results: In the present study, among the 68 final year dental students, 37 students (54.4%) were male 31 students (45/6%) were female the mean and standard deviation of the age of the participants was 25.12 ± 2.3 years. In this study, the mean and standard deviation of total attitude score of final year dental students was equal to 22.80 ± 6.74 and the total attitude score of final year dental students based on Likert Scale was lower than the average. Most of the students reported the quality of posterior composite training to meet practical needs as poor. Conclusion: Based on the results, the awareness and attitude of final year dental students in relation to posterior composite restoration training was less than average and weak, respectively. There was no significant difference was observed between the knowledge and attitude scores with the gender and age.

Rubber Dam Isolation Survey among Dental Students in Al-Qassim University and How to Promote its Usage.

Rubber dam isolation is crucial in dentistry, but its use varies among dental students. There is a need to assess their awareness, attitudes, and practices and find ways to promote its usage. To evaluate dental students' knowledge and practices regarding rubber dam isolation and identify barriers to its use. The study employed a cross-sectional design to assess dental students' knowledge and practices regarding rubber dam isolation. Data were collected from dental students at Al-Qassim University during the period from January to March 2023. A convenience sampling method was used, involving students from the third, fourth, and fifth academic years, with a total of 62 questionnaires distributed. A pre-tested questionnaire consisting of 11 closed-ended questions was used to collect data, and the analysis was performed using SPSS version 21, with results presented through descriptive statistics. Only 21% always used rubber dam for amalgam restorations, while 53.2% used it for composite restorations. Over 70% believed their education on rubber dam was adequate. The main barriers were difficulty (40.3%) and time constraints (53.2%). About 68% felt rubber dam should be mandatory for composite treatments. Dental students need more education and training to bridge the gap between knowledge and practice concerning rubber dam isolation. Implementing it can enhance the quality of dental care.

Posterior tooth anatomy: wax carving. Part 2

This second article in the two-part series on wax carving provides a step-by-step guide focusing on the coronal anatomy of whole posterior teeth. The exercises are primarily designed to help clinicians simulate and master the carving and shaping of extensive dental amalgam and posterior resin composite restorations, as well as for use in designing fixed and removable prosthodontic restorations. CPD/Clinical Relevance: Knowledge and understanding of the anatomy of posterior teeth is a key skill in dentistry.

Barodontalgias, dental and orofacial barotraumas: a survey in Swiss divers and caisson workers.

Changing ambient pressure can lead to medical conditions in body cavities filled with air. Intraoral pain elicited by changes in pressure is referred to as barodontalgia. Dental barotraumas are defined as pressure-induced damages of teeth and restorations. The pathophysiologic background so far is not completely clear. The present study deals with dental and orofacial symptoms which can occur as a result of pressure variations. With the aid of cantonal administrations, diving associations, and tunnel construction firms, 520 pressure-exposed individuals (499 scuba/ professional divers, 21 caisson workers operating at excess pressure) were questioned regarding dental problems. A personal interview was conducted with affected individuals. Problems in the dental area were experienced by 15% of all respondents. Toothaches were suffered by 10.2% of the participants. Tooth injuries occurred in 6.3% of all interviewees (26 fractured amalgam restorations, 4 crown fractures, 3 losses of tooth fragments). A proportion of 11.3% among the respondents complained about temporomandibular joint problems or mucosal irritations (for example aphthae) related to the mouthpieces. Barotraumas outside the dental area were incurred by 31.9% of the divers. Of these, 69.9% concerned the ears and 65.6% occurred during the descent. Based on the results obtained from the survey and taking into account the current literature, recommendations for the prevention of barotraumas in divers and caisson workers were prepared. Diagnostic exclusion of dental pathologies and avoidance of retentive reconstruction materials are important factors for the prevention of barodontalgias and dental barotraumas.

Assessment of Prevalence and Causative Factors for Replacement of Composite and Amalgam Restorations: An Observational Study

ABSTRACT Aim: This study intends to evaluate the frequency and causes of replacement for failed amalgam and composite dental restorations. Methodology: A cross-sectional study comprising female patients with failed permanent composite and amalgam restorations aged 15–60 years old was carried out at the dental clinics of Qassim University. Using a self-structured proforma, demographic data and causes for restoration failure were recorded. The effectiveness of the restorations was assessed by using the Ryge criteria after performing clinical and radiographic examinations. The Statistical Package for Social Science was used for the statistical analysis. Results: It is found that 84.6% of the 299 unsuccessful restorations examined were composite, and 15.4% were amalgam. The main reason for dental failure for both amalgam (95.6%) and composite (93.28%) restorations was secondary caries. Failure of amalgam restoration was largely caused by poor marginal adaptation. With varied incidences between amalgam and composite restorations, typical complaints included discomfort, sensitivity, pain, and food impaction with soreness. The main justification for replacement in amalgam restorations was sensitivity. Repair and replacement rates were similar for amalgam, composite, and mandibular/maxillary restorations. Moreover, 21.1% of individuals overall reported no symptoms, with 8.7% in the amalgam group and 23.3% in the composite group with significant differences (χ 2 = 34.28, P = 0.001). Conclusion: According to the current study, secondary caries was found to be the main reason for both amalgam and composite restoration failure. The main problems reported were sensitivity, discomfort, and pain with amalgam showing more sensitivity-related failures.

Association between dental restorations and artefacts on head magnetic resonance images in paediatric patients.

Magnetic resonance imaging (MRI) has become an important diagnostic tool for paediatric patients. The association between dental restorations and MRI artefacts/distortions, however, is unclear. To investigate the association between dental restorations and artefacts in head MRI in children. This retrospective analysis included patients who underwent head MRI and dental examination at Ramathibodi Hospital from January 2015 to March 2021. From dental records and dental radiographs, a dentist reviewed the amount and type of restorative materials used. Two radiologists examined the MRI scans in five sequences for the presence of distortions and quantified the magnitude and grading of any artefacts. Ninety-four patients aged 3-15 years were included. Twenty-four patients who received preformed metal crowns (PMCs) had MRI distortions. Subjects with no restorations or with tooth-coloured material or amalgam restorations or both did not exhibit distortions. The number of PMCs was related to the size of an artefact. Almost all distortions were confined to the oral cavity and maxillary sinus and did not affect the diagnostic brain area. Among the commonly used dental restorative materials for children, only PMCs were associated with artefacts on head MRI scans.

The “Phase Down” of Dental Amalgam Restorations - What are the Criteria for Replacement and Indication?

The “Phase Down” of Dental Amalgam Restorations - What are the Criteria for Replacement and Indication?