Tooth autotransplantation and resin composite reshaping as a multidisciplinary approach for treating dental agenesia: A 10-year follow-up.

CASE REPORT: This case report describes the multidisciplinary approach performed in a 9-year-old male patient with dental agenesia affecting teeth 21 and 22. Autotransplantation of the right upper second premolar with incomplete rhizogenesis to the missing area was combined with coronary reshaping with resin composite and orthodontic therapy. The treatment began with the extraction of the deciduous upper left central incisor, bone preparation for the recipient site of the donor tooth, atraumatic extraction of the right upper second premolar and immediate autotransplantation in the surgically prepared recipient site. Subsequently, sutures to reposition the flap and a rigid splint were performed. After 12 months, coronary reshaping of the autotransplanted tooth with resin composite was carried out. Orthodontic treatment involving the use of a fixed appliance was used to correct the interdental spaces and achieve adequate occlusion. Clinical and radiographic follow-up 10 years after tooth autotransplantation and 9 years after reshaping revealed partial obliteration of the pulp chamber, root resorption, ankylosis and the presence of endodontic treatment. CONCLUSIONS: The long-term outcomes highlighted that tooth autotransplantation represents a biologically and cost-effective procedure for replacing missing teeth in young patients, particularly in cases of incomplete rhizogenesis of the autotransplanted tooth. CLINICAL SIGNIFICANCE: This case report discusses tooth autotransplantation and resin composite reshaping as viable and long-term clinical options for treating young patients with dental agenesis.

EFFECT OF LOW-LEVEL DIODE LASER ON DENTIN TOPOGRAPHY AND SYMPTOMATIC NONCARIOUS CERVICAL LESIONS PRIOR TO COMPOSITE RESTORATIONS: A SPLIT-MOUTH RANDOMIZED CONTROLLED TRIAL.

OBJECTIVES: This study assessed alterations in sensitivity among symptomatic noncarious cervical lesions (NCCLs) following the application of 3 low-level diode laser wavelengths before composite restoration. It analyzed the changes in dentin topography using a scanning electron microscope (SEM). MATERIALS AND METHODS: Nine patients with 36 NCCLs were randomly assigned intra-individually to 4 groups based on the laser wavelength: laser simulation, 445 nm, 660 nm, and 970 nm. Cavity preparation, irradiation, and composite restoration were performed for each lesion. Sensitivity to cold stimuli was recorded using a visual analog scale (VAS) before the intervention (baseline) and at 1 day, 14 days, 1-, 3-, and 6-month. Pulp sensibility was recorded using an electrical pulp tester (EPT) at baseline, before treatment, and at 3- and 6-month. Additionally, an in vitro examination was performed on 12 extracted human molars to yield 12 dentin discs. Each disc was randomly divided into 4 quadrants to receive the same laser wavelengths to determine the diameters of the tubules using SEM. Results were analyzed statistically for clinical studies by the Friedman test, while ANOVA (RM-ANOVA) was conducted in-vitro, followed by the Bonferroni test in the case of significance (P < .05). RESULTS: VAS readings decreased across all groups, with a significant decrease observed for 660 nm and 970 nm from 14 days to 6-month, while at 445 nm there was a significant decrease at 6-month compared to the control (P < .05). EPT showed a significant decrease in pain threshold levels at 660 nm and 970 nm at 3- and 6-month, while 445 nm showed a significant decrease at 6-month compared to the control (P < .05). The mean tubular diameter at 445 nm decreased, with no significant difference from the control, whereas a significant decrease was found at 660 nm and 970 nm compared to the control (P < .05). CONCLUSIONS: Prior to composite restoration in symptomatic NCCLs, diode lasers with a wavelength of 660 nm showed the highest reduction in sensitivity, followed by 970 nm, whereas 445 nm diode lasers showed the least reduction. Additionally, diode lasers with wavelengths of 660 and 970 nm reduced the width of the dentinal tubules (DT) without inducing melting, as viewed under SEM.

The stamp technique for direct restoration in a ICDAS 4 carious lesion: A 4-year follow-up.

OBJECTIVE: This case report described the use of a stamping technique associated with a bulk fill composite to restore an ICDAS 4 carious lesion on a posterior tooth. The 4-year follow-up is also presented. CLINICAL CONSIDERATIONS: A 32-year-old patient presented a carious lesion on tooth 36 with an underlying dark shadow at the dentin seen from the noncavitated enamel occlusal surface, which was compatible with an ICDAS 4 carious lesion. The lesion was radiographically detected and the caries disease was treated with dietary and hygiene habits orientations. Before accessing the lesion and selectively removing the carious tissue, an occlusal stamp was made by applying a flowable resin composite to copy the anatomy of the noncavitated enamel surface. The cavity was restored using a bulk fill resin composite (Opus Bulk Fill, FGM) with 4-mm-thick increments. Before curing the last increment, a Teflon band was adapted at the uncured bulk fill composite surface and the occlusal stamp made with the flowable composite was pressed against it to reproduce the natural characteristics and initial occlusal anatomy. The top surface was light-activated for 40 s. After 4 years, small wear could be seen in the restoration, but still within clinically acceptable levels. CONCLUSION: The occlusal stamp technique allows reproduction of the natural anatomy of teeth affected by ICDAS 4 carious lesions with good clinical longevity over 4 years. CLINICAL SIGNIFICANCE: This case report presents the use of the stamp technique to restore a tooth affected by an ICDAS 4 lesion, in which a carious process reached the dentin and the enamel anatomy was still preserved. The bulk fill resin composite associated with the occlusal stamp was chosen to quickly restore the cavity with clinical predictability. Bulk fill composites allow the insertion of up to 4-mm-thick increments and offer lower shrinkage stress, good clinical longevity and a less time-consuming procedure in cases of posterior teeth, especially if associated with the stamp technique.

Comparing fracture resistance on bovine incisors restored by tooth fragment reattachment versus direct composite restoration techniques.

BACKGROUND/AIM: Anterior teeth are prone to traumatic dental injuries (TDIs). Although a number of techniques ranging from original tooth fragment reattachment (TFR) to direct composite restoration (DCR) can be used to restore uncomplicated crown fractures, there is no consensus on which method is best. The purpose of this study was to investigate the fracture resistance of bovine incisors restored by two different techniques (TFR and DCR) in three different fracture models. MATERIALS AND METHODS: Sixty extracted bovine lower incisors were randomly divided into three groups (n = 20). Angle, oblique, or transverse sections of all the teeth in a group were prepared by using a disk. The cut surfaces were scanned, and the cross-sectional areas (CSA) of the enamel and dentin were measured. Half the teeth in each group were restored by DCR (n = 10) and the other half by TFR (n = 10). The forces required to fracture the restored teeth were then measured using a Universal testing machine, and the fracture modes were analyzed (cohesive, adhesive, or mixed). RESULTS: No statistically significant differences between the TFR and DCR restorations were detected for total and enamel CSAs in any of the restoration shapes (p > .067). The fracture forces required to break DCR angle and transverse restorations were significantly greater than for the corresponding shapes restored with TFR (p < .033). However, the difference in the forces needed to fracture oblique section restorations by DCR or TFR was not statistically significant (p = .239), despite a similar trend (143.4 ± 51 N and 120.9 ± 25 N, respectively). CONCLUSION: This study revealed that a greater force is required to fracture teeth restored by the DCR than by the TFR technique, especially for a transverse section. This demonstrates that restoring a fractured tooth provides a superior outcome compared to reattaching the fractured fragment.

Survival analysis of fragment reattachments and direct composite restorations in permanent teeth after dental traumatic injuries.

BACKGROUND/AIM: In case of crown fractures after traumatic dental injuries, the affected teeth can be restored either with reattachment of the fractured fragment or with a direct composite restoration. So far, longevity data for reattachments and direct composite restorations with regard to different failure types (pulp necrosis and infection, restoration loss) are scarce. Therefore, the aim of this retrospective study was to evaluate the restorative and biological survival of reattached fragments and composite restorations after crown fractures in permanent teeth. MATERIAL AND METHODS: Dental records of patients treated between 2000 and 2018 were retrospectively analysed regarding the restoration (reattachment or direct composite restorations) of teeth with crown fractures. Survival (no further intervention) and restorative and/or biological failure of all restored teeth were recorded. Statistical analysis was performed using Kaplan-Meier statistics, and the mean annual failure rates for two and 5 years were calculated. Furthermore, the effect of potential risk factors on survival was assessed. Log-rank tests and univariate Cox regression models (likelihood ratio tests) were used to assess the univariate effect of all variables of interest. Variables with a p-value ≤.10 were included in a multivariate Cox regression model with shared frailty (p < .05). RESULTS: Overall, 164 patients with 235 teeth (uncomplicated crown fracture: N = 201, complicated crown fracture: N = 34) were included (1.6 ± 2.5 years observation time). Of these, 59 teeth were restored with reattachment of the fragment and 176 with a composite restoration. Overall, composite restorations had a significantly higher survival rate than reattachments (p = .002). The cumulative survival after 2 years was 42.9% and 65.0% for teeth treated with a reattachment (mAFR = 34.5%) and a composite restoration (mAFR = 19.3%), respectively. When differentiating between failure types, restoration failure and pulp necrosis were significantly more frequently detected in reattached crown fractures compared to composite restorations (restorative failure: p = .001; biological failure: p = .036). In the multivariate Cox regression model, the variable jaw and luxation significantly influenced the survival when the tooth was restored with a composite restoration. The survival was not influenced by the fracture type. CONCLUSIONS: Restorative and biological failures were more frequently detected when the tooth was restored with a reattached fragment compared to a direct composite restoration. Both, restoration failure and pulp necrosis with infection should be considered as frequent complications after restoration of crown-fractured teeth which emphasizes the necessity of regular and short follow-up intervals throughout the first 2 years.

Evaluation of the proximal contact tightness in class II resin composite restorations using different contact forming instruments: a 1-year randomized controlled clinical trial.

BACKGROUND: Proper proximal contact in direct composite restorations is crucial for periodontal health. Over a one-year period, this study was conducted to assess successive biological changes in proximal contact tightness PCT in class II direct composite restorations and the adjacent teeth by applying sectional matrix system along with different contact forming instruments. METHODS: 72 direct compound class II composite restorations were performed in patients aged 18-40 years and divided into 4 groups: Group I (n = 18): proximal contact was restored with Palodent plus sectional matrix system, Group II (n = 18): Trimax as contact forming instrument, Group III (n = 18): Perform as contact forming instrument and Group IV (n = 18): Contact pro as contact forming instrument. All contact forming instruments were used along with Palodent plus matrix system. PCT was measured using a digital force gauge before (T0), immediate post operative (T1) and at 3 (T2), 6 (T3), 9 (T4), and 12 months (T5) after restorative treatment. Using One-Way ANOVA, Tukey's post hoc test, and Bonferroni correction, PCT values were compared between groups before and after the intervention restoration. Meanwhile, for comparisons within groups, a paired t-test was conducted (p ≤ 0.05). RESULTS: Contact forming instruments combined with Palodent plus sectional matrix system achieved better PCT. Trimax led to a statistically considerable tighter proximal contacts than the other groups (p < 0.05). No statistically significant difference was found in PCT between Contact pro-2, Perform and Palodent plus sectional matrix system. By means of multivariate analysis, the PCT between both T0 and T1 were increased (p < 0.001) and then it decreased till T5. CONCLUSIONS: The use of transparent contact forming instruments achieved greater PCT compared to Palodent sectional matrix system alone that gradually decreased throughout 12 months and reached the PCT between the natural teeth. Using Trimax system provided the tightest proximal contacts. Additionally, digital force gauge was confirmed as an inclusive and accurate method to quantify PCT. TRIAL REGISTRATION: ClinicalTrials.gov NCT05749640: 24/5/2022.

Regenerative endodontic treatment of an immature incisor tooth with a novel platelet-rich product: A five-year follow-up case report.

This case report presents a five-year follow-up and the management of a necrotic, immature incisor tooth treated by a novel platelet-rich plasma/platelet extract solution and platelet-rich fibrin (PRP-PES/PRF) and the restoration by using a stress-reduced direct composite restoration (SRDC) technique. The patient with a broken maxillary lateral tooth was referred to our clinic. Extra/intra-oral examinations were within normal limits. The nonvital tooth having an apical lesion and open-apical apex was treated with a regenerative endodontic treatment procedure (REP), and further root development with continued apical closure was shown in the follow-ups up to 60 months. In conclusion, the SRDC and PRP-PES/PRF combination can be an opportunity for the teeth requiring post-restoration. In contrast to the treatment strategy susceptible to weakening or fracturing the patient's tooth root, the REP approach may lead to a better prognosis for the patient's tooth.

Effect of Nd:YAG laser irradiation, used as a desensitizing strategy, on bond strength to simulated hypersensitive dentin.

OBJECTIVES: To evaluate the effect of Nd:YAG laser irradiation as a prior desensitizing strategy on immediate and medium-term microtensile bond strength (µTBS) to simulated hypersensitive dentin. MATERIALS AND METHODS: Flat mid-coronal dentin was obtained from third molars and submitted to a 600-grit SiC paper (1 min; N: normal dentin) or subsequently challenged with citric acid (6%, 1 min; H: simulated hypersensitive dentin). Afterwards, dentin was or was not (C: control; HC, NC - each n = 7) irradiated with Nd:YAG laser (L: laser; 1.0 W/10 Hz/100 mJ/4 irradiations of 50-60 s; HL, NL - each n = 7). A 2-step self-etch adhesive (Clearfil SE Bond) was applied and composite (Filtek Z350) buildups were constructed. After 24-h (distilled water/37 °C) storage, specimens were sectioned into beams and tested (µTBS; 0.5 mm/min) immediately or after 6-month aging. Three-way ANOVA and Tukey tests were applied (α = 0.05). Qualitative evaluation of the adhesive interface (n = 1 extra tooth per group) was performed by Confocal Laser Scanning Microscopy. RESULTS: Substrate condition (p < 0.001), laser irradiation (p < 0.001), and aging (p = 0.002) influenced the results. Furthermore, there was interaction between substrate and irradiation (p < 0.001). Laser irradiation favored µTBS exclusively to hypersensitive dentin immediately and after aging. µTBS to hypersensitive dentin was higher than that to the normal substrate only when it was laser-irradiated. In any case, immediate µTBS was always higher than that after aging. CLSM revealed longer and more numerous resin tags for simulated hypersensitive dentin, and shorter and fewer resin tags for laser-irradiated dentin. No differences were observed in the hybrid layer itself. CONCLUSION: Nd:YAG laser irradiation prior to restoration favored the µTBS of a self-etch adhesive and resin composite to hypersensitive dentin. CLINICAL RELEVANCE: Desensitizing strategies are usually tried before performing restorative treatments in hypersensitive dentin; therefore, they may influence behavior of the adhesive interface established. However, instead of causing concern, Nd:YAG laser irradiation revealed a favorable effect on the aforementioned interface.

The effect of different application modes of a 1-step self-etch adhesive on the clinical performance of Class I composite restorations: A randomized controlled clinical trial.

OBJECTIVE: To evaluate the clinical performance of a 1-step self-etch dentin adhesive that was applied according to the manufacturers' recommendations, doubling the adhesive application time and layer in Class I cavities with a composite resin. MATERIALS AND METHODS: A total of 39 patients aged between 14 and 43 (mean age: 19.1) years were enrolled in the study. Each patient received three restorations. In these three restorations, a 1-step self-etch adhesive was applied according to the manufacturer's recommendations (control group), by doubling the adhesive application time, and with double layers. The restorations were evaluated according to modified USPHS criteria at baseline, and 1, 2, 3, and 4-year recalls. RESULTS: After 4 years, the success rate was 100% for restorations with the adhesive applied according to the manufacturers' recommendations, 96.9% for restorations applied by doubling the adhesive application time, and 93.8% for restorations applied with double adhesive layers. There was no significant difference between the three application methods among all the evaluation periods regarding the evaluation criteria. CONCLUSIONS: The 4-year success rates of a 1-step self-etch dentin adhesive that was applied according to the manufacturers' recommendation, by doubling the adhesive application time, and with double layers were excellent. CLINICAL SIGNIFICANCE: It is not recommended to double the adhesive application time nor apply a double layer of a 1-step self-etch adhesive because it does not improve the clinical performance of Class I composite restorations.

The effect of chlorhexidine primer application on the clinical performance of composite restorations: a literature review.

To discuss the effectiveness of chlorhexidine (CHX) used as therapeutic dentin primer in adhesively bonded composite restorations. OVERVIEW: An electronic search in MEDLINE database, accessed through PubMed was conducted. No restrictions of languages and date of publication were made. The following key words were used: "chlorhexidine", "composite" and "composite resins." Clinical studies in which CHX was used during bonding procedures were included in this review. Six studies met the inclusion criteria. Of these, five studies were carried out on noncarious cervical lesions (NCCL). Only one study was carried out on class II preparation of permanent molars. In all studies, either etch-and-rinse and self-etch adhesive systems were used during bonding procedures. On the basis of the reviewed clinical trials, it can be concluded that CHX primer application does not seem to influence clinical outcome of composite restorations. CLINICAL SIGNIFICANCE: Current scientific evidence cannot neither strongly recommend nor discourage the application of CHX as therapeutic primer in composite restorations. Studies with longer follow-up periods with adhesive restorations placed on dentin after caries removal, rather than only on NCCL, are desirable to further investigate the therapeutic effect of CHX during bonding procedures.

Impact of various finishing and polishing techniques and composite materials on Candida albicans biofilm formation.

Candida albicans biofilms are commonly associated with severe oral infections. In dentistry, prosthetic and restorative materials are potential structures for the adhesion of C. albicans facilitating the formation of Candida biofilm and infection. Three composite resins (Charisma Classic, Sonic Fill, Estelite ∑ Quick) and two finishing-polishing systems (Biscover LV, Dental Finishing Disc) were evaluated for Candida biofilm formation. A Candida biofilm assay showed that both the resin and the finishing/polishing procedures affect Candida biofilm formation. Specifically, Candida biofilm formation was significantly lower in Sonic Fill resin than both Charisma Classic and Estelite ∑ Quick (P = .021). The type of finishing and polishing procedure also significantly affected the Candida biofilm formation to composite material (P < .001). Candida biofilm formation was more advanced after Biscover LV procedure than Dental Finishing Disc procedure.

Effect of access cavity design on gaps and void formation in resin composite restorations following root canal treatment on extracted teeth.

AIM: To evaluate the influence of ultraconservative endodontic access cavities (UEC) on gaps and void formation in resin composite restorations in extracted two-rooted maxillary premolars after root canal treatment. Traditional endodontic access cavities (TEC) were used as a reference for comparison. METHODOLOGY: Two-rooted maxillary premolars were scanned in a micro-computed tomographic (micro-CT) device, matched based on similar anatomical features and allocated into two groups (n = 10) according to the design of the access cavity: TEC or UEC. Teeth were mounted on a mannequin head and a single operator performed the treatment, including endodontic access cavity preparation, root canal detection, preparation, filling and restoration procedures, under magnification. For restorative procedure, a bulk fill flowable layer was applied initially followed by an overlaying of regular composite. After restoration procedures, a new micro-CT scan was performed to check the quality of the coronal restoration by analysing the percentage volume of empty spaces present in the tooth-restoration interface (gaps) and inside the restoration (voids). Data were analysed statistically using Shapiro-Wilk and Student's t tests with a significance level of 5%. RESULTS: All specimens had gaps and voids. There were significant differences between the access cavity designs regarding the formation of voids with significantly more voids associated with the UEC (P < 0.05). Gap formation did not differ between groups (P > 0.05). CONCLUSION: The access cavity design used during root canal treatment interfered with the adaptation of the restorative material. The minimally invasive access cavity design was associated with a significantly greater number of voids within restorations.

Minimally invasive removal of tooth-colored restorations: evaluation of a novel handpiece using the fluorescence-aided identification technique (FIT).

OBJECTIVES: This study investigated the ability of the fluorescence-aided identification technique (FIT) facilitated by a novel handpiece to simplify the removal of tooth-colored composite restorations with water-cooled rotating instruments. MATERIALS AND METHODS: Five undergraduate students and five dentists (6-14 years of professional experience) were asked to remove dental restorations in vitro using both the conventional technique (CT) and the fluorescence-aided identification technique. The FIT method was performed on teeth restored in addition to the fluorescent composite resin with the non-fluorescent (FIT1) and fluorescent (FIT2) bonding agent. CEREC scans were superimposed and three-dimensionally analyzed with the software OraCheck 2.13 with respect to the cavity surface area still covered with composite resin and the volume of the needlessly removed sound hard tissue. Additionally, the removal procedure was timed. RESULTS: The FIT2 group showed the most promising results: the smallest cavity surface area covered by composite resin independent of the professional expertise, and for the dentist group, the smallest amount of removed sound hard tissue and the fastest removal. CONCLUSIONS: Using the fiber optic of the handpiece for fluorescence excitation has been proven to be effective for performing the FIT, and therefore, to improve the removal of tooth-colored restorations. CLINICAL RELEVANCE: This study is basic research to encourage the integration of fluorescence inducing light sources in dental treatment units by the manufacturers as a prerequisite for a simplified daily use of the FIT.

Effect of cavity lining on the restoration of root surface carious lesions: a split-mouth, 5-year randomized controlled clinical trial.

OBJECTIVE: To compare the clinical performance of cavities with no lining and lining with resin-modified glass ionomer (RMGIC) for the treatment of root surface carious lesions. MATERIALS AND METHODS: The study included 39 patients (mean age, 39.6 years) who visited the university hospital for the treatment of at least 2 root surface carious lesions. After caries removal, the depth, length, and height of the cavities were measured. Using a paired-tooth design and simple randomization technique, the cavities were assigned to one of two groups that were either unlined or lined with RMGIC (Glass Liner II). All cavities were restored with a nanohybrid resin-based composite (Clearfil Majesty Esthetic). One hundred restorations (50 lined, 50 unlined) were placed. Two examiners other than the operator blindly evaluated the restorations at the follow-ups according to the modified Havemann criteria for marginal adaptation, anatomic form, marginal staining, caries in the adjacent tooth structure, caries at the cavosurface margin, and tooth sensitivity. Chi-square, Fisher's exact, Mann-Whitney U, and Cochran Q tests were used for the analysis (p < 0.05). RESULTS: At the 5-year follow-up, 12 restorations were failed. However, there was no significant difference between the marginal adaptation and marginal staining of the materials (p = 0.526 and p = 0.893, respectively). Four caries lesions were detected in the adjacent tooth structure and at the cavosurface margin at the 5-year assessment. CONCLUSION: There was no significant difference in the clinical performance of the lined and unlined restorations. CLINICAL RELEVANCE: The clinical performance of both unlined and RMGIC-lined cavities at the 5-year post-restoration assessment was acceptable. TRIAL REGISTRATION: NCT03802539.

Fiber-reinforced composite fixed dental prosthesis using an additive manufactured silicone index.

OBJECTIVE: Digital tools such as facial and intraoral digitizers and additive manufacturing (AM) technologies assist restorative treatments. The objective of the present manuscript was to describe a workflow procedure for treatment planning and fabricating a fiber-reinforced composite fixed dental prosthesis (FDP) replacing an absent maxillary lateral incisor, using additively manufactured silicone indices to facilitate the clinical intervention. CLINICAL CONSIDERATIONS: The elaboration of a direct fiber-reinforced composite restoration is a technique sensitive procedure which might be time-consuming for the clinician. The digital waxing helped to determine the exact position and size of the lingual wings and connectors of the fiber-reinforced FDP and to design a three-piece index. And the AM of the index helped to transfer the information to the patient's dentition accurately. CONCLUSIONS: The protocol minimizes the time of clinical intervention by facilitating the transference of the virtual diagnostic waxing teeth into the patient's mouth. The three-piece silicone index provides an individualized path of insertion of each index part while also providing a customized space and location of the lingual wings of the restoration. CLINICAL SIGNIFICANCE: The usage of AM silicone indices facilitates the clinical intervention by translating the size and position of the diagnostic wax-up teeth into the patient's mouth, minimizing clinical procedure's time.

Next generation of dentists moving to amalgam-free dentistry: Survey of posterior restorations teaching in North America.

OBJECTIVES: The dental field is gradually reducing the use of amalgam and moving towards adhesive restoration. This change is in accordance with the advancement and improvement of composite resin materials and adhesion systems. Consequently, posterior cavity preparations teaching should be re-examined to determine whether dental schools are adapting their curriculum to fit the current trends in dentistry and what rationale supports their decisions. METHODS: An online questionnaire was constructed to assess the time dedicated to teaching composite materials and amalgam, in addition to the principles of posterior preparations, for composite restorations in North American dental schools. RESULTS: A total 33 schools responded to the questionnaire. A large variation was found in teaching methods and techniques of posterior restorations. The reasoning for teaching amalgam restorations was diverse as were the principles of composite resin preparation taught. CONCLUSION: No agreed principles of cavity preparation for resin composite restorations were found, as opposed to explicit agreement on amalgam cavity preparations. The results demonstrate a lack of clear guidelines for cavity preparation of resin composite restorations. Dental schools may benefit when a consensus on this topic is achieved.

Evaluation of the influence of various restoration techniques on fracture resistance of endodontically treated teeth with different cavity wall thicknesses.

AIMS: The aim of this study was to compare the effect of different restoration techniques on fracture resistance of endodontically treated teeth with different wall thicknesses. MATERIALS AND METHODS: Extracted and endodontically treated 210 premolars were randomly divided into three thickness groups [2 mm (A), 1.5 mm (B), and 1 mm (C)] and, each group was further divided into seven restoration subgroups (n = 10): direct composite (control) (K), composite with fiber on cavity floor (KT), composite with fiber on occlusal level (KO), fiber post and composite (FP), inlay (L), fiber on cavity floor and inlay (LT), and inlay and fiber on occlusal level (LO). Fracture test was performed, and data were compared with Kruskal-Wallis and Mann-Whitney U tests (P < 0.05). RESULTS: There were no differences between the subgroups in A and C statistically (P > 0.05). However, in B, KO subgroup showed statistically higher values (P = 0.039). CONCLUSION: Wall support of 2 mm was adequate, and support of 1 mm was completely insufficient. When the wall thickness was 1.5 mm, direct restoration with fiber at the occlusal level significantly improved resistance.

Direct resin composite restoration of maxillary central incisors using a 3D-printed template: two clinical cases.

BACKGROUND: Three-dimensional (3D) printing technology is used widely in dentistry for applications including implant surgery, oral and maxillofacial surgery, orthognathic surgery, endodontics and prosthodontics. Using a 3D-printed template makes performing the repair procedure faster and more convenient. The aesthetic restoration of anterior teeth can recover facial beauty, enhance speaking and chewing functions and improve the quality of life of the patient. CASE PRESENTATION: This article describes two kinds of clinical cases including fractured teeth and dental caries. In both, a 3D-printed template was used for direct resin composite restoration of maxillary central incisors. A 3D-printed template was built using the following 3-step process: data acquisition was conducted via intra-oral scanning, virtual modeling was performed using an imaging process, and manufacturing was performed using a 3D printer. Aesthetically restoring the maxillary incisors with the assistance of the 3D-printed template achieved the anticipated results, and the patients were very satisfied with the effect. CONCLUSIONS: The direct resin composite restoration of maxillary central incisors using a 3D-printed template represents a rapid, convenient, aesthetic and functional option for treating maxillary central incisors. A 3D-printed template is therefore an acceptable and reliable alternative to traditional direct composite restoration of maxillary central incisors including fractured teeth and dental caries.

Survival Rates of Stainless Steel Crowns and Multi-Surface Composite Restorations Placed by Dental Students in a Pediatric Clinic.

PURPOSE: This study examined survival rates of multi-surface composite restorations and stainless steel crowns (SSCs) placed by students in a pediatric dental clinic as well as the length of time it takes for restorations to be replaced with stainless steel crowns. STUDY DESIGN: Data from electronic dental records for all children with at least one 2-surface composite restorations or SSCs on a primary first or second molar from January 1, 2007 to September 30, 2015 were analyzed. The primary outcome was the time to a new restoration or SSC on the same tooth, with time to a crown as a secondary outcome. Descriptive statistics were obtained and the cumulative incidence of the event of interest was estimated using 95% confidence intervals and compared between groups using Fine-Gray regression. RESULTS: A total of 6,288 teeth from 2,044 children were analyzed. Three years after the initial procedure, 1.5% of SSCs and 21% of 2 and 3 surface composite restorations failed and needed a replacement (Hazard Ratio [HR]= 14; 95% Confidence interval [CI] 9-22, p<0.001). Also, 6.8% of composite restorations needed replacement with SSCs' (HR=4; 95% CI: 3-7). CONCLUSIONS: The study demonstrates that stainless steel crowns had a higher survival rate than multi-surface composite resins placed by students at a pediatric dental clinic in primary molars of children.

[Paradigm shift in conservative dentistry: the end of the amalgam era]. / Paradigmaváltás a fogmegtartó kezelésben: az amalgámkorszak vége.

Dental amalgam has been used for more than 150 years due to its beneficial mechanical properties and durability in dentistry. In the past and to date, many questions about amalgam restorations have arisen, especially regarding the mercury content, which has been the subject of global disputes. By presenting the past and present of the 'amalgam issue', the aim of our paper is to display the current position of international literature. This summary is based on the publications in the PubMed database, the guidelines of the Council of European Dentists. Although the use of dental amalgam is widespread, concerns have been raised about the adverse effect on human health and the environment, focusing on its heavy metal pollution during waste treatment. In 2017, the European Union (EU) adopted the so-called Mercury Regulation, based on the United Nations Minamata Convention on Mercury, the recommendations of which are presented in the present review. This Regulation includes the requirement for EU Member States to develop a national action plan for the phase-down of amalgam. The feasibility plan for complete phase-out may be guaranteed by 2030. The authors discuss the advantages and disadvantages of possible amalgam alternatives by presenting glass-ionomers and resin-based composites. In the future, more material research programmes and long-term follow-up studies are necessary. In addition to several global health organizations, the Council of European Dentists also draws attention to prevent dental caries, expecting to reduce the number of restorations. Orv Hetil. 2018; 159(42): 1700-1709.