Teaching of composite restoration repair in Brazilian dental schools.

OBJECTIVES: The aim was to investigate aspects of the teaching of restoration repair as a minimally invasive alternative to replacing defective direct composite restorations in undergraduate curricula teaching programs in Brazilian dental schools. METHODS: A 14-item validated survey questionnaire was mailed to directors/coordinators of operative/restorative dentistry teachers of Brazilian Dental Schools. Data were collected on demographic characteristics of the teachers and institutions, together with questions on the teaching of the repair of defective resin-based composite restorations as part of the school curriculum; the rationale behind the teaching; the nature of the teaching (preclinical and/or clinical); how techniques were taught, indications for repair, operative techniques, materials used, patient acceptability and expected longevity of completed repairs. RESULTS: Two hundred and twenty-two (94%) directors/ coordinators of dental curricula in Brazil were contacted. One hundred and thirty-one directors/coordinators (59%) replied, providing the e-mail address from the teacher responsible for the operative/restorative dentistry program in their school. Of these, 104 responded to the questionnaire (79% response rate). Ninety-three (89%) of the participating schools reported teaching composite repairs as an alternative to replacing restorations. Of the theoretical content, 43% was taught at preclinical and clinical levels, whereas most practical experience (53%) was acquired at clinical levels. Eighty-eight schools (95%) reported tooth substance preservation being the main reason for teaching repair techniques. All schools that taught repairs reported high patient acceptability. CONCLUSIONS: The teaching of composite restoration repair as an alternative to restoration replacement is established in undergraduate programs in most of the Brazilian dental schools surveyed. CLINICAL SIGNIFICANCE: The reasons for teaching restoration repair in Brazil were found to be quite unanimous among teachers, especially regarding the preservation of tooth structure. Variations were found in the clinical indications for repair, suggesting the need for further investigations. Monitoring repaired restorations should be encouraged and could contribute to future studies.

Evidence-practice gap in treatment decisions about defective composite and amalgam restorations among Brazilian dentists

Better understanding of dentists' decision-making about defective restorations is needed to close the evidence-practice gap (EPG). This study aimed to quantify the EPG about defective restorations and identify dentist factors associated with this EPG. Methods: 216 dentists from São Paulo State, Brazil, completed a questionnaire about three clinical case scenarios involving defective composite restorations with cementum-dentin margins (case 1) and enamel margins (case 2), and an amalgam (case 3) restoration. Dentists were asked what treatment, if any, they would recommend, including preventive treatment, polishing, re-surfacing, or repairing the restoration, or replacing the entire restoration. Replacing the entire restoration in any of these three scenarios was classified as inconsistent with the evidence, comprising an EPG. Bivariate analyses using Chi-square, ANOVA, or multiple comparison tests were performed (p<.05). Results: for defective composite restorations, 49% and 55% of dentists chose to replace the entire restoration for cases 1 and 2, respectively. Twenty-nine percent of dentists chose to replace the entire amalgam restoration. Dentists were significantly more likely to choose to replace the defective amalgam restoration than the composite restoration with a defect at the cementum-dentin margins or the enamel margins (both at p < .001). Female dentists were more likely to choose a conservative treatment than male dentists for cases 1 (p=.034) and 2 (p=.009). Dentists with a higher percentage of patients interested in individualized caries prevention were also more conservative in case 1 (p=.045). Conclusion: a substantial EPG regarding treatment decisions for defective restorations exists, especially for composite restorations. This study adds to the international evidence that an EPG exists in this clinical area and that global strategies need to be developed to close the gap

Fixed Partial Denture Designed by Combining the Whole 3D Digital Surface Morphology of the Provisional Restoration and Abutment Teeth Surfaces.

We introduce a new digital workflow to fabricate a fixed partial denture (FPD) utilizing the three-dimensional surface morphology of provisional restoration (PR) and abutment teeth. Scanned images of the full maxilla with abutment teeth, full maxilla with PR, and PR alone were superimposed. The surfaces of the final FPD were designed based on the entire morphology of the PR and abutment teeth surfaces. The inner and outer surfaces converged at the margin lines of the abutment teeth. Fine modifications to the final FPD design were performed manually, and the final FPD was fabricated and successfully installed in the patient.

Bone Dimensional Change Following Immediate Implant Placement in Posterior Teeth with CBCT: A 6-Month Prospective Clinical Study.

This prospective clinical study aimed to evaluate the peri-implant hard tissue dimensional change at 6 months of immediate implant placement with bone graft materials in the posterior area using cone-beam computed tomography (CBCT). Twelve dental implants were placed concurrently following tooth extraction in the posterior area and filled with xenograft particles. The CBCT images were taken immediately after surgical procedures and then at 6 months follow-up. To evaluate the hard tissue changes, the vertical and horizontal bone thickness were analyzed and measured using ImageJ software. Paired t-test or Wilcoxon match-pair signed-rank test was done to analyze the changes of hard tissue values at the same level between immediately and 6 months following immediate implant placement. Independent t-test or Mann-Whitney U test was used to analyze the dimensional change in the vertical and horizontal direction in buccal and lingual aspects. The level of significance was set at p value = 0.05. All implants were successfully osseointegrated. At 6 months follow-up, the vertical bone change at the buccal aspect was -0.69 mm and at the lingual aspect -0.39 mm. For horizontal bone thickness, the bone dimensional changes at 0, 1, 5, and 9 mm levels from the implant platform were -0.62 mm, -0.70 mm, -0.24 mm, and -0.22 mm, respectively. A significant bone reduction was observed in all measurement levels during the 6 months after implant placement (p value < 0.05). It was noted that even with bone grafting, a decrease in bone thickness was seen following the immediate implant placement. Therefore, this technique can be an alternative method to place the implant in the posterior area.

Challenges in diagnosing and managing non-cavitated occlusal caries lesions. A Literature overview and a report of a case.

AIM: Aim of this literature overview was to analyze the diagnostic procedures of hidden caries lesions and to present a restorative protocol. METHODS: A literature overview was performed in order to evaluate hidden caries etiological hypothesis and the reported prevalence. The diagnostic procedure is performed with the aid of an intra-oral fluorescence based camera and the restorative procedure is completed with the use of a novel bisphenol-A free composite. RESULTS: Non cavitated occlusal caries lesions prevalence is high in young adults population. Diagnosis of hidden caries requires both high sensitivity and specificity. CONCLUSIONS: The novel diagnostic and restorative protocol showed to be highly effective in hidden caries assessment and restoration.

Inverse gas chromatography in the examination of adhesion between tooth hard tissues and restorative dental materials.

The adhesion is a crucial issue in the bonding of dental restorative materials to tooth hard tissues. A strong and durable bond between artificial and natural materials is responsible for the success of the restoration in the oral cavity; therefore it has to be thoroughly examined before new restorative material is introduced to the market and used clinically. Among all methods used to examine bonding strength, most of them require a large number of healthy teeth to be conducted. In this paper, the bond strength between tooth hard tissues (dentin and enamel) and an exemplary restorative composite was examined with the non-conventional method, i.e. inverse gas chromatography. Dentin and enamel from bovine teeth were separated and subjected to the standard preparation procedure using the 3-component etch-and-rinse commercial bonding system. Tissues, as well as commercial restorative composite, were examined using inverse gas chromatography. The work of adhesion between dentin/enamel and composite was calculated. Obtained results were compared with the values of shear bond strength of six configurations, i.e. etched dentin/enamel-composite, primed dentin/enamel-composite, and bonded dentin/enamel-composite. All obtained results proved that there is a correlation between the values describing bond strength obtained from inverse gas chromatography and direct mechanical tests (shear bond strength tests). It proves that inverse gas chromatography is a powerful perspective tool for the examination of bond strength between tooth hard tissues and potential dental materials without using a large number of health tooth tissues.

Clinical and radiographic comparative study to evaluate the efficacy of restoring destroyed primary incisors using two different techniques-A pilot study.

OBJECTIVE: The restoration of destroyed maxillary primary incisors is difficult because of the insufficient amount of coronal structure. This pilot study aimed to compare the efficacy of composite posts technique and glass fiber posts technique in restoring destroyed primary incisors. MATERIALS AND METHODS: Thirty-six destroyed maxillary primary incisors in 11 children with early childhood caries were randomly assigned after endodontic treatment into two groups: glass fiber posts (n = 18) and composite resin posts (n = 18). Blinded clinical evaluation was made at 3, 6, 9, and 12 months and Blinded radiographic evaluation was made at 6 and 12 months. The evaluation was according to the FDI criteria. Data were analyzed with Fisher's exact test (α = .05). RESULT: After 12 months post-treatment, the success rates were 88.2% in glass fiber posts group and 70.6% in composite resin posts group. There was no statistically significant difference between the two groups according to the evaluation criteria (p-value >.05). CONCLUSION: Glass fiber posts technique and Composite posts technique may be used in the restoration of destroyed primary incisors.

Clinical efficacy of ceramic versus resin-based composite endocrowns in Chinese adults: study protocol for a randomized controlled trial.

BACKGROUND: Endocrown restoration is widely used to restore endodontically treated teeth. However, the clinical effects of different computer-aided design/computer-aided manufacturing (CAD/CAM) materials for endocrown restoration are not clear. The primary objective of this trial is to compare the clinical efficacy of resin-based bloc and ceramic endocrowns for restoring endodontically treated teeth. METHODS: The proposed resin-based bloc and ceramic endocrown assessment trial is a parallel group-designed randomized controlled trial. We will recruit 156 adults between 18 and 75 years old with a minimum of one such molar. The inclusion criteria were good oral hygiene habits, root apex of molar without evident damage, receipt of standard endodontic treatment, need for endocrown restoration, and only one endocrown restoration performed per patient. Patients participating in another study or those with systemic diseases, disabilities, or known allergies to used materials will be excluded. All patients will be randomized and restored with resin-based bloc and ceramic endocrown according to a random number table. Clinical evaluations will be performed at baseline and after treatment at 6, 12, and 24 months, in accordance with the modified Federation Dentaire Internationale (FDI) criteria, by two independent evaluators. The primary outcome is marginal adaptation; secondary outcomes include wear, tooth integrity, fracture of material and retention, marginal staining, and patient view. All data will be analyzed by an independent statistician. Signed rank-sum tests will be used for intragroup comparisons. Wilcoxon rank-sum tests will be used for intergroup comparisons. Hierarchical logistic regression will be used to adjust the baseline and other important indicators. DISCUSSION: This study will investigate endocrowns of two CAD/CAM materials for endodontically treated molars. The results may help clinicians choose the better CAD/CAM material option and explain to patients the advantages and disadvantages of these two materials with evidence-based support. For patients, the results may lead to improvement in long-term restoration. TRIAL REGISTRATION: ClinicalTrials.gov NCT04033380. Registered on 24 July 2019.

Five year evaluation of the complications observed in porcelain fused to metal (PFM) crowns placed at a university hospital.

OBJECTIVE: To determine the frequency of complications in crowns cemented over a 5-year period in a tertiary care hospital and also to report the survival of these crowns. METHODS: The retrospective cross-sectional study was conducted at the Aga Khan University Hospital, Karachi, from March 2017 to March 2018 and comprised porcelain fused-to-metal crowns placed on the anterior or posterior teeth that were fabricated at the institutional laboratory and were placed in institutional dental clinics in the preceding 5 years. Porcelain-fused to-metal The crowns were clinically and radio-graphically evaluated in a duration of two months for presence/absence of complications. Factors associated with the failure of the crowns, their survival and the impact of covariates, like gender, flossing and bruxism, on the survival time were determined. Data was analysed using SPSS 22. RESULTS: There were 150 crowns related to 107 patients who had a mean age of 45.0±11.4 years. The most common complication observed was open proximal contacts 9(6%) followed by de-cementation 8(5.3%), porcelain chipping 9(6%) and abutment fracture 2(1.3%). The 5-year survival rate of the crowns was 127(84.7%). The mean follow-up time was 57.2±1.0 months. Overall, year-wise survival of PFM crowns for one year till five years was 147 (98%), 144 (96%), 135 (90%), 130 (86%) and 119 (79%) respectively. CONCLUSIONS: The porcelain-fused-to-metal crowns had a high 5-year survival rate. Open proximal contacts represented the most common complication.

Quality of Information Regarding Repair Restorations on Dentist Websites: Systematic Search and Analysis.

BACKGROUND: Repairing instead of replacing partially defective dental restorations represents a minimally invasive treatment concept, and repairs are associated with advantages over complete restoration replacement. To participate in the shared decision-making process when facing partially defective restorations, patients need to be aware of the indications, limitations, and advantages or disadvantages of repairs. Patients are increasingly using the internet to gain health information like this online. OBJECTIVE: We aimed to assess the quality of German-speaking dentist websites on repairs of partially defective restorations. METHODS: Three electronic search engines were used to identify German-speaking websites of dental practices mentioning repairs. Regarding information on repairs, websites were assessed for (1) technical and functional aspects, (2) comprehensiveness of information, and (3) generic quality and risk of bias. Domains 1 and 3 were scored using validated tools (LIDA and DISCERN). Comprehensiveness was assessed using a criterion checklist related to evidence, advantages and disadvantages, restorations and defects suitable for repairs, and information regarding technical implementation. Generalized linear modeling was used to assess the impact of practice-specific parameters (practice location, practice setting, dental society membership, and year of examination or license to practice dentistry) on the quality of information. An overall quality score was calculated by averaging the quality scores of all three domains and used as primary outcome parameter. Quality scores of all three domains were also assessed individually and used as secondary outcomes. RESULTS: Fifty websites were included. The median score of quality of information was 23.2% (interquartile range [IQR] 21.7%-26.2%). Technical and functional aspects (55.2% [IQR 51.7%-58.6%]) showed significantly higher quality than comprehensiveness of information (8.3% [IQR 8.3%-16.7%]) and generic quality and risk of bias (3.6% [IQR 0.0%-7.1%]; P<.001/Wilcoxon). Quality scores were not related to practice-specific parameters (P>.05/generalized linear modeling). CONCLUSIONS: The quality of German-speaking dentist websites on repairs was limited. Despite sufficient technical and functional quality, the provided information was neither comprehensive nor trustworthy. There is great need to improve the quality of information to fully and reliably inform patients, thereby allowing shared decision making.

Antibacterial Properties of Nanoparticles in Dental Restorative Materials. A Systematic Review and Meta-Analysis.

Background and Objectives: Nanotechnology has become a significant area of research focused mainly on increasing the antibacterial and mechanical properties of dental materials. The aim of the present systematic review and meta-analysis was to examine and quantitatively analyze the current evidence for the addition of different nanoparticles into dental restorative materials, to determine whether their incorporation increases the antibacterial/antimicrobial properties of the materials. Materials and Methods: A literature search was performed in the Pubmed, Scopus, and Embase databases, up to December 2018, following PRISMA (Preferred Reporting Items for Systematic Review and Meta-Analysis) guidelines for systematic reviews and meta-analyses. Results: A total of 624 papers were identified in the initial search. After screening the texts and applying inclusion criteria, only 11 of these were selected for quantitative analysis. The incorporation of nanoparticles led to a significant increase (p-value <0.01) in the antibacterial capacity of all the dental materials synthesized in comparison with control materials. Conclusions: The incorporation of nanoparticles into dental restorative materials was a favorable option; the antibacterial activity of nanoparticle-modified dental materials was significantly higher compared with the original unmodified materials, TiO2 nanoparticles providing the greatest benefits. However, the high heterogeneity among the articles reviewed points to the need for further research and the application of standardized research protocols.

Retrospective study of patients with amelogenesis imperfecta treated with different bonded restoration techniques.

OBJECTIVE: The aim of this retrospective study was to evaluate clinical success and satisfaction of patients with amelogenesis imperfecta treated with three different types of bonded restorations at a university clinic. MATERIALS AND METHODS: One hundred fifty-four restorations in 15 subjects with mean age of 17.3 years (SD 8.2) were evaluated after treatment with three different types of bonded restorations: all ceramic enamel-dentin bonded restorations, prefabricated composite veneers, and direct composite resin restorations. A modified version of the Californian Dental Association system for quality evaluation of dental care and a questionnaire assessing patient satisfaction were used for classification. The restorations were evaluated with respect to patient satisfaction, esthetics, technical, and biological complications. RESULTS: Mean observation period for the restorations was 42.5 months (SD 35.6). All restorations were in place at the time of the examination. Surface and color calibration showed a success of 95% for the ceramic enamel-dentin bonded restorations, 44% for the direct composite resin restorations, and 0% for the prefabricated composite veneers. The same pattern was evident for anatomy and marginal integrity. The subjects reported a high degree of satisfaction with both the esthetics and function of their restorations. CONCLUSION: The results indicated that all ceramic restorations demonstrated the best results for patients with amelogenesis imperfecta.

Reparación de defecto localizado en restauración de amalgama como tratamiento de mínima intervención en cariología / Repair of a localized defect in a restoration with amalgam filling as minimal intervention treatment in cariology

Introducción: La reparación de restauraciones ha sido estudiada desde muy recientemente, pero a pesar de haber demostrado efectividad y mejoras en la terapéutica de la caries dental, aún tiene seguidores y detractores, lo que justifica la necesidad de estudios que sigan avalando tales prácticas. Objetivo: Describir, a través de la presentación de un caso, la reparación de un defecto localizado en una restauración de amalgama como tratamiento de mínima intervención en cariología. Presentación del caso: Paciente femenina de 16 años con antecedentes de salud acude a consulta refiriendo una pequeña fractura de restauración en diente 4.6 desde hace varias semanas. La regularización del defecto en la restauración, la mínima preparación cavitaria, la eliminación del fragmento de la base intermedia, la protección del complejo dentino-pulpar y el llenado de la cavidad resultante, fueron los primeros pasos de una técnica que se cumplimentó luego del pulido final de la interface tejido dentario-restauración y se evolucionó cinco años después. Se evidenció el estado y presencia de la reparación de la restauración realizada, sin fracturas añadidas, microfiltraciones, sintomatologías, desplazamientos ni pérdidas de la continuidad. Conclusiones: La reparación del defecto localizado de amalgama se realizó con el fin de preservar los tejidos dentarios no afectados como lo dicta la mínima intervención en cariología. Cinco años más tarde, la evolución evidencia una práctica que se tradujo en resultados satisfactorios e incremento de la calidad de vida de la paciente(AU)

Introduction: Restoration repair has been studied recently; but, even when it has demonstrated effectiveness and improvements in the therapy of dental caries, it still has followers and detractors that justify the need for studies that continue supporting such practices. Objective: To describe, through a case presentation, the repair of a defect located in a restoration with amalgam filling as minimal intervention treatment in cariology. Case presentation: Sixteen-year-old female patient with health history that went to the clinic reporting a small fracture of a restoration performed in tooth 4.6 several weeks ago. The regularization of the defect in the restoration, minimum cavity preparation, elimination of the fragment of the intermediate base, protection of the dentin-pulp complex, and filling of the resulting cavity were the first steps of a technique that was completed after the final polishing of the dental tissue/restoration interface that was evolved five years later. The status and presence of the restoration repair performed without added fractures, microfiltration, symptomatology, displacement or loss of continuity was evidenced. Conclusions: The repair of the localized defect in a restoration with amalgam filling was performed with the aim of preserving the unaffected dental tissues as dictated by minimal intervention in cariology. Five years later, the patient´s evolution shows a practice that resulted in satisfactory results and an increase in the patient's quality of life(AU)

Using Er:YAG laser to remove lithium disilicate crowns from zirconia implant abutments: An in vitro study.

BACKGROUND: When implants are restored with cement-retained restorations, prosthetic retrievability can be difficult and often requires sectioning using rotary instruments. Sometimes repeated removals of a cement-retained implant crown are needed such as for treatment of peri-implantitis or immediate implant provisionalization. The purpose of this study was to evaluate the effect of erbium-doped yttrium aluminum garnet (Er:YAG) laser as a non-invasive treatment modality to remove lithium disilicate crowns from zirconia implant abutments following long-term cementation, repetitive debonding and re-cementation, and short-term retrieval. MATERIAL AND METHODS: Twenty identical lithium disilicate crowns were cemented onto zirconia prefabricated abutments using composite resin cement. Ten cemented crowns were removed at 48 hours after cementation as a short-term group (ST), while another 10 were removed 6 months after cementation as a long-term group (LT). To mimicking repetitive recementation and retrieval, the LT crowns were then recemented and removed after 48 hours as a long-term recemention (LTR) group. The LTR crowns were then again recemented and removed after 48 hours as a long-term repeated recemention (LTRR) group. Er:YAG laser was used to facilitate the retrieval of these crowns. recorded and analyzed using ANOVA and t-test. The surfaces of the crown and the abutment were further examined using light microscopy and scanning electron microscopy (SEM). Temperature changes of the abutment and crown upto 10 minutes were also measured and statistically analyzed (paired t-test). RESULTS: The average times of crown removal from zirconia abutments were 4 minutes (min) and 42 second (sec) in LT to 3 min 24 sec in LTR, and 3 min 12 sec in LTRR and ST groups. LTR took the longest time to remove, statistically (ANOVA and t-test, p < .001). No statistical differences were observed among the removal times of LTR, LTRR, and ST groups (t-test, p = .246, .246 and 1). SEM examination of the material surface showed no visual surface damaging from treatment with Er:YAG laser. The temperatures during irradiation ranged from 18.4°C to 20°C and 22.2°C to 24.5°C (Paired t-test, p < .0001) for the abutment and the crown during irradiation from 1 min to 10 mins. CONCLUSIONS: Long-term cementation can increase time in lithium disilicate crown removal from zirconia abutment using Er:YAG. Er:YAG laser is a non-invasive tool to remove cement-retained implant prostheses and should be considered as a viable alternative to rotary instruments.

Repair potential of a new glass hybrid restorative system.

BACKGROUND: Repair of a failed amalgam or composite resin (CR) restoration has been extremely studied and proposed as a routine clinical treatment option; however, repair potential of glass ionomer-based restorative materials was not studied sufficiently in the literature. AIM: The aim of this study is to evaluate the repair potential of a glass hybrid (GH) restorative repaired either by the same material (GH) or CR after different surface treatments using microtensile bond strength (µTBS) test. METHODS AND MATERIALS: One hundred and twenty bar-shaped (2 × 2 × 8 mm) GH blocks were prepared. After aging, the specimens were divided into two groups (n = 60) and five subgroups (n = 12). The specimens in Group I were repaired with the following protocols: (a) no treatment + GH, (b) diamond bur (B) + GH, (c) cavity conditioner + GH, (d) cavity conditioner + universal adhesive (A) + GH, (e) A + GH, and specimens in Group II were repaired with (a) no treatment + CR, (b) B + CR, (c) B + A + CR, (d) 40% phosphoric acid + A + CR, (e) A + CR. The specimens that were subjected to µTBS testing, scanning electron microscopy evaluations, and fracture modes were determined. Data were analyzed using Kruskal-Wallis and Mann-Whitney U tests (P = 0.05). RESULTS: Repair using CR resulted in higher bond strengths (P < 0.001). The lowest bond strength was obtained in Group Ie. The highest bond strength was obtained when GH was roughened in Group IIc. CONCLUSION: Repair of restorative GH with CR appears as a preferred option to improve the bond strength.

Técnica innovadora semidirecta de Individualización con endoposte de fibra / Innovative chairside technique of Individualized fiber post

La restauración con sistema de endoposte de fibra mediante técnica de individualización o anatómica es conocida desde hace tiempo. Se presenta una alternativa para ser realizada de manera semidirecta mediante la confección de un modelo flexible translúcido que permite reducir algunos inconvenientes de la técnica directa de individualización. El material empleado para el modelo es un material de bajo costo y accesible para cualquier profesional que desee emplear esta alternativa de restauración. (AU)

Anatomical or individualized fiber post technique has been used for many years now. An alternative is presented to be done chairside with a flexible and translucid model obtained that allows to reduce some drawbacks of the direct anatomical technique. The material used is less expensive than other options and might be used by any professional that want to learn this technique. (AU)

Anesthetic Management of a Pediatric Patient With Pelizaeus-Merzbacher Syndrome: A Case Report.

A 3-year-old pediatric patient with previously diagnosed Pelizaeus-Merzbacher syndrome presented for outpatient dental restoration. Given the infrequency of this demyelinating disorder, an anesthetic plan was tailored to address the patient's hypotonia and aspiration risk, as well as minimize potential complications including seizures, hemodynamic instability, and postoperative respiratory support. Multimodal analgesia, along with an appropriate ventilation strategy and normothermia, allowed the patient to successfully undergo a general anesthetic and be safely discharged home the same day.

SDR® vs traditional composite in class II restorations in primary molars.

This study aims to compare the clinical characteristics of a new flowable resin-based composite with those of a traditional composite when applied to deciduous molars for class II restorations. Twentyeight children between 6-12 years of age, with paired minimal Class II cavities present on their primary molars, were chosen. The paired cavities were restored with either a microhybrid composite or a new flowable resin-based composite. The composites were assigned to cavities in either the right or left side of the mouth, using random allocation tables. Each pair of restorations were clinically assessed at sixmonth intervals following the United States Public Health Service criteria. The prevalence of carious lesions was higher in maxillar molars (53.6%) compared to the mandibular molars (46.4%). At 24 months, Charlie or Delta scores in the paired groups were not seen in any patient, thus demonstrating a clinical success. The statistical analysis using Pearson’s chi-squared test did not reveal significant p-values for any parameter except the proximal contact showing significant p-values for this parameter. SDR appears to be the material of choice for the restoration of deciduous teeth due to its clinical features shown at 24 months as well as its ease and speed of application.

Deep infiltration for the treatment of hypomineralized enamel lesions in a patient with molar incisor hypomineralization: a clinical case.

This case report presents the technique of deep infiltration for the treatment of hypomineralized enamel lesions in a patient affected by molar incisor hypomineralization (MIH) with the purpose of obtaining an aesthetic improvement in the affected vestibular enamel. Deep infiltration treatment involves a sequence of steps starting with an initial mechanical abrasion of the outside surface of the enamel, followed by a phase of chemical erosion using 15% hydrochloric acid, penetration through the porosity of the enamel by a very fluid resin, and finally the repair of the thin layer of lost enamel using a composite. The aesthetic improvement of the elements affected by hypomineralized lesions is discernible immediately following treatment and becomes more accentuated with time. At the expense of minimal damage to surface enamel, deep infiltration enables treatment of all types of white spot enamel lesions, regardless of aetiology, offering the possibility of restoring an aesthetically pleasing smile for patients.

Analysis of flexural strength and contact pressure after simulated chairside adjustment of pressed lithium disilicate glass-ceramic.

STATEMENT OF PROBLEM: Research evaluating load-to-failure of pressed lithium disilicate glass-ceramic (LDGC) with a clinically validated test after adjustment and repair procedures is scarce. PURPOSE: The purpose of this in vitro study was to investigate the effect of the simulated chairside adjustment of the intaglio surface of monolithic pressed LDGC and procedures intended to repair damage. MATERIAL AND METHODS: A total of 423 IPS e.max Press (Ivoclar Vivadent AG) disks (15 mm diameter, 1 mm height) were used in the study. The material was tested by using an equibiaxial loading arrangement (n≥30/group) and a contact pressure test (n≥20/group). Specimens were assigned to 1 of 14 groups. One-half was assigned to the equibiaxial load test and the other half underwent contact pressure testing. Testing was performed in 2 parts, before glazing and after glazing. Before-glazing specimens were devested and entered in the test protocol, while after-glazing specimens were devested and glazed before entering the test protocol. Equibiaxial flexure test specimens were placed on a ring-on-ring apparatus and loaded until failure. Contact pressure specimens were cemented to epoxy resin blocks with a resin cement and loaded with a 50-mm diameter hemisphere until failure. Tests were performed on a universal testing machine with a crosshead speed of 0.5 mm/min. Weibull statistics and likelihood ratio contour plots determined intergroup differences (95% confidence bounds). RESULTS: Before glazing, the equibiaxial flexural strength test and the Weibull and likelihood ratio contour plots demonstrated a significantly higher failure strength for 1EC (188 MPa) than that of the damaged and/or repaired groups. Glazing following diamond-adjustment (1EGG) was the most beneficial post-damage procedure (176 MPa). Regarding the contact pressure test, the Weibull and likelihood ratio contour plots revealed no significant difference between the 1PC (98 MPa) and 1PGG (98 MPa) groups. Diamond-adjustment, without glazing (1EG and 1PG), resulted in the next-to-lowest equibiaxial flexure strength and the lowest contact pressure. After glazing, the strength of all the groups, when subjected to glazing following devesting, increased in comparison with corresponding groups in the before-glazing part of the study. CONCLUSIONS: A glazing treatment improved the mechanical properties of diamond-adjusted IPS e.max Press disks when evaluated by equibiaxial flexure and contact pressure tests.