An assessment of Brazilian dentists' knowledge about tooth fragment reattachment: A cross-sectional study.

BACKGROUND/AIM: Crown fractures are common traumatic dental injuries and tooth fragment reattachment is a viable option for restoring a fractured tooth. The aim of this study was to assess the knowledge and experience of dentists in the Federal District regarding the tooth fragment reattachment technique for enamel and dentin fractures. MATERIALS AND METHODS: For the cross-sectional observational study, an electronic form was designed with objective and self-report questions for dentists. The data were analyzed using descriptive statistics, with their absolute and relative frequencies. For the analysis of categorical variables, the nonparametric chi-squared or Fisher exact association tests were used in the statistical software R (version 4.2.1). RESULTS: A total of 416 dentists participated in the study (58.9% female and 41.1% male). Of these, 70% declared they knew about fragment reattachment, but only 42.3% reported previous experience with this procedure. The most common storage medium used for the fractured fragment was milk (78.1%), and the bonding material used for reattachment was light-cured composite resin (86.3%). A majority (66.3%) reported that for a patient with enamel and dentin fracture, with the crown fragment in good condition, they would choose to do the reattachment. CONCLUSION: Dentists demonstrated that they had adequate knowledge about the tooth fragment technique, although many did not have previous experience with this procedure.

Influence of two carbodiimides on the bond strength of universal adhesives to dentin.

The pretreatment of dentin with cross-linking agents during bonding procedures has been proposed to improve the mechanical properties of the collagen in the hybrid layer and reduce the biodegradation of the adhesive interface. The aim of this study was to evaluate the influence of pretreatment with two carbodiimides on the dentin bond strength of universal adhesives, after thermocycling. Three universal adhesives in the self-etching mode were used (Single Bond Universal-SBU, Clearfil Universal-CLU and Ambar Universal-ABU). A self-etching adhesive system (Clearfil SE Bond-CSB) was used as control. Two carbodiimides, 1-ethyl-3-(3'-dimethylaminopropyl)-carbodiimide (EDC) and N,N'-dicyclohexylcarbodiimide (DCC), were applied for 1 min. The excess solution was removed with absorbent paper and the universal adhesives were applied. The specimens were stored for 24 h in distilled water at 37 °C or 10,000 thermal cycles (5-55 °C, 30 s) and then were prepared for microtensile bond strength test (n = 4 teeth, average of 21 sticks per group). Data were analyzed using three-way ANOVA and Tukey's (α = 5%). After 24 h, SBU and CSB had statistically similar bond strength values for the control groups (22.07 ± 9.03 and 19.82 ± 7.28 MPa), with EDC (30.21 ± 11.30 and 19.67 ± 5.36 MPa) and DCC (30.12 ± 13.43 and 19.82 ± 7.28 MPa) pretreatments (p > 0.05). The use of EDC (32.57 ± 9.60 MPa) and DCC (24.71 ± 9.87 MPa) showed statistically higher bond strength for CLU than for the control group (14.62 ± 6.16 MPa; p < 0.05). After thermocycling, the SBU, CLU, and CSB groups showed statistically similar bond strengths with the use of EDC (27.08 ± 8.44; 18.74 ± 5.41; and 24.55 ± 10.43 MPa) and without the use of cross linkers (20.06 ± 7.99; 22.55 ± 9.04; and 26.54 ± 10.13 MPa; p > 0.05). Groups tested after 24 h in distilled water presented higher bond strength than those submitted to thermocycling. It can be concluded that the use of cross linkers influenced the immediate bond strength of the universal adhesives, and this was dependent on the combination of the adhesive system and type of carbodiimide. The use of EDC increased the immediate bond strength of CLU. DCC increased the bond strength of ABU at 24 h, but the values were lower than those of the control group after aging for three out of the four adhesives.

Do anterior and posterior teeth treated with post-and-core restorations have similar failure rates? A systematic review and meta-analysis.

STATEMENT OF PROBLEM: The association between tooth type, location in the dental arch, and selection of a post-and-core system for endodontically treated teeth is unclear. Information on the influence of these parameters on the failure rate of teeth treated with post-and-core restorations is needed. PURPOSE: The purpose of this systematic review and meta-analysis was to assess the available evidence on the failure rates of anterior and posterior teeth treated with post-and-core restorations. MATERIAL AND METHODS: A search was performed in PubMed, Scopus, Web of Science, Latin American and Caribbean Health Sciences Literature database, Brazilian Library in Dentistry, Cochrane Library, and Gray literature for randomized clinical trials comparing the failure rates of anterior and posterior teeth treated with post-and-core restorations. The risk of bias tool from the Cochrane Collaboration was used for quality assessment of the studies. RESULTS: The search strategy identified 2526 articles, and 6 studies were included in the meta-analysis. No difference in the failure rate of post-and-core restorations placed in anterior and posterior teeth was found in most studies. The risk ratio for anterior versus posterior teeth was 1.06 (95% confidence interval [CI], 0.69-1.64; P=.79). The risk ratio for incisors versus canines was 3.08 (95% CI, 0.56-17.04; P=.20) and that for premolars versus molars was 0.45 (95% CI, 0.12-1.74; P=.25). The risk ratio for prefabricated glass fiber posts on anterior versus posterior teeth was 1.13 (95% CI, 0.61-2.09; P=.70) and that for metal posts was 1.10 (95% CI, 0.64-1.91; P=.72). CONCLUSIONS: The failure rates in anterior and posterior teeth treated with post-and-core restorations were similar at short- to medium-term follow-up. More well-designed clinical trials comparing the survival and failure rates of anterior and posterior teeth treated with post-and-core restorations with longer follow-up times are needed.

Esthetic and functional management of an ankylosed central incisor with a conservative restorative approach.

In this case report, we share a conservative and simple restorative management approach for a relatively complex esthetic situation on an adult patient with an ankylosed maxillary central incisor in infra-occlusion. A 37-year-old healthy female patient presented for a consultation with a chief complaint of an unappealing smile. The intraoral exam revealed tooth #8 (FDI 11) was in obvious and significant infra-occlusion due to altered eruption. Periapical radiographs of this area were non-contributory and all teeth responded within normal limits to pulp vitality tests. After review of several treatment options, the patient opted for a conservative restorative approach in which a partial ceramic veneer was planned for the ankylosed tooth, while composite resin was used on the contralateral central incisor to achieve a symmetric and pleasant result. CLINICAL SIGNIFICANCE: A relatively complex clinical problem was satisfactorily resolved with a very conservative option in which composite resin and a ceramic veneer were used to restore an asymmetric smile.

Lithium silicate endocrown fabricated with a CAD-CAM system: A functional and esthetic protocol.

An endocrown restoration is an alternative approach to complete crowns with intraradicular cores or dowels for the restoration of endodontically treated teeth. Endocrowns conserve tooth structure and require fewer dental visits. This approach has been widely used, and various materials and techniques have been reported. Computer-aided design and computer-aided manufacturing (CAD-CAM) systems can generate and store libraries of teeth with various anatomies in their database, and diagnostic tooth waxing may not be required. However, occlusal adjustments after the cementation of indirect restorations are often frustrating. Thus, a rapid and efficient way of addressing this challenge is necessary. This clinical report presents a protocol for the fabrication and delivery of an endocrown by using the biogeneric design mode with lithium silicate-based ceramic adjusted before its complete sintering.

Planning extensive esthetic restorations for anterior teeth: use of waxed-up study casts and composite resin mock-ups.

The aim of this case report is to highlight the importance of appropriate planning protocols when direct composite resin restorations are used to solve extensive esthetic problems. A 30-year-old patient complained about her small maxillary anterior teeth and short upper lip. All teeth were healthy and light colored, and the patient exhibited good oral hygiene. The anterior teeth were relatively short, resulting in a compromised esthetic relationship between height and width. The maxillary and mandibular right central incisors were in an edge-to-edge relationship. After diagnostic casts and waxed-up study casts were obtained, occlusal adjustment and recontouring of the incisal and labial surfaces of the mandibular right central incisor were performed to increase overjet. To increase the volume of the upper lip, composite resin restorations were planned for the maxillary anterior teeth. To confirm that the contours and color of the new smile were acceptable to the patient, composite resin esthetic mock-ups were made directly in the mouth before the definitive procedure. After definitive restoration of the anterior teeth, additional occlusal adjustments were performed. At the 36-month follow-up, no fracturing or severe wear of the restorations was observed. The restored anterior guidance provided excellent function after 3 years of clinical service.

Fabrication of lithium silicate ceramic veneers with a CAD/CAM approach: a clinical report of cleidocranial dysplasia.

The fabrication of minimally invasive ceramic veneers remains a challenge for dental restorations involving computer-aided design and computer-aided manufacturing (CAD/CAM). The application of an appropriate CAD/CAM protocol and correlation mode not only simplifies the fabrication of ceramic veneers but also improves the resulting esthetics. Ceramic veneers can restore tooth abnormalities caused by disorders such as cleidocranial dysplasia, enamel hypoplasia, or supernumerary teeth. This report illustrates the fabrication of dental veneers with a new lithium silicate ceramic and the CAD/CAM technique in a patient with cleidocranial dysplasia.

Esthetic, occlusal, and periodontal rehabilitation of anterior teeth with minimum thickness porcelain laminate veneers.

Ceramic veneers of minimum thickness provide satisfactory esthetic outcomes while preserving the dental structure. Dental ceramics can both improve the esthetic appearance and reestablish the strength and function of teeth. In worn anterior teeth, functional surfaces, for example, anterior and lateral guidance, can be restored effectively. The characteristics of dental ceramics, such as color stability and mechanical and optical properties, make this material a good choice for indirect restorations, especially when optimum function and esthetics are required. This clinical report presents an occlusal, periodontal, and restorative solution with minimum thickness glass ceramic veneers for worn anterior teeth with multiple diastemas.

Bond strength of fiber-reinforced posts to deproteinized root canal dentin.

AIM: This study evaluated the push-out bond strength of cemented fiber posts after deproteinization of root canal dentin walls with NaOCl. The effect of the application of an antioxidant solution (sodium ascorbate) was also evaluated. MATERIALS AND METHODS: A three-step etch-and-rinse (Scotch-bond - 3M Espe) and a one-step self-etching adhesive (Xeno III - Dentsply Caulk) were evaluated. Thirty bovine incisor roots were divided into 3 groups: a. Irrigation with physiologic solution (control). b. Deproteinization with 10 minutes irrigation of 5% NaOCl. c. Deproteinization with NaOCl followed by 10 minutes irrigation with 10% ascorbic acid. Fiber posts were cemented with a dual-cured cement (Rely X ARC - 3M ESPE). The push-out bond strength was evaluated after 24 hours of storage in distilled water. The data were analyzed with three-way ANOVA, one-way ANOVA and Tukey's test (α = 0.05). RESULTS: There were significant differences between groups (p < 0.05). The bond strength of Scotchbond was not influenced by the deproteinization. Xeno III showed a decrease in bond strength when deproteinized with 5% NaOCl (p < 0.05). For Xeno III, the subsequent irrigation with ascorbic acid was able to reverse the effect of the deproteinization. Considering the radicular thirds, the bond strength varied in the sequence-apical < middle < coronal. CONCLUSION: Only the all-in-one adhesive was influenced by the deproteinization. Considering the respective control groups, both systems showed similar bond strength results. CLINICAL SIGNIFICANCE: The decreased bond strength of the self-etching adhesive following deproteinization seams to be related to the oxidant effect of the NaOCl solution and the subsequent irrigation with ascorbic acid was able to reverse the effect of the deproteinization.

Using chemical vapor deposition diamond finishing burs for conservative esthetic procedures.

The article demonstrates how chemical vapor deposition (CVD) diamond burs were used in a simple esthetic and cosmetic procedure to treat discolored anterior teeth. A patient who experienced discoloration after bleaching was treated with direct resin composite veneers. Excess restorative material close to the periodontium was removed with a CVD diamond bur attached to an ultrasonic handpiece. The results indicate that CVD diamond burs are appropriate for removing excess material at the gingival margins of resin composite restorations without damaging the periodontium.

Layering technique with non-Vita shading concepts.

Managing teeth with hypoplasia stains or discoloration using composite resin materials is challenging. When appraising hypoplasia stains, the substrate color and thickness of the material must be considered. The non-Vita shading system has a reduced number of layers, primarily dentin and enamel, which is known as the natural layering concept. The incremental approach of this system allows the masking of substrates with color differences and the reproduction of the optical characteristics of chromaticity, translucency or opacity as well as the value (luminosity). The present study demonstrates and discusses the color sequence for the natural reproduction of tooth structures using an alternative composite resin system from the classical Vita scale.

Macroabrasion and/or Partial Veneers: Techniques for the Removal of Localized White Spots.

Macroabrasion is a technique for the removal of localized white spots using a high-speed, intermittent high speed turbine finishing diamond tip. It is fast, safe, efficient, and an alternative to enamel microabrasion. However, when the stain is deeper, these localized intrinsic stains or defects can be treated with partial direct veneers. A conservative preparation should be done and that allows stratification of the resin to mask the hypoplasia and provide naturalness to the tooth. Thus, the objective of this work is to demonstrate, through a clinical case, macroabrasion and a partial veneer from the preparation, restoration, to the finishing and polishing to remove hypoplastic stains.

Color Stability of Ceramic Veneers Luted With Resin Cements and Pre-Heated Composites: 12 Months Follow-Up.

The objective was to evaluate the color stability of ceramic veneers luted with resin cements and pre-heated composite resins (60oC) for 12 months, and determine the degree of conversion (DC) of the luting agents. Two resin cements (AllCem Veneer, light-cured (LRC) and AllCem, dual-cured (DRC)] and three composite resins [Z100 (MNCR-minifilled), Herculite Classic (MHCR-micro-hybrid) and Durafill (MCCR-microfilled)] were used for cementing 0.8-mm-thick lithium-silicate glass-ceramic laminates (Suprinity, shade B2-HT, Vita) on bovine enamel (n=10). The specimens were stored at 37oC in distilled water. CIELab parameters were determined at 24h after luting (baseline), 7, 30, 90, 180 days and 12 months. Three specimens were prepared for DC evaluation, performed by micro-Raman spectroscopy. Data were analyzed by ANOVA and Tukey's test (a=5%). For ΔEab and ΔE00, there were significant differences for luting material (p<0.001), time (p<0.001), and double interaction (p<0.001). The groups cemented with MHCR (1 year), MCCR (90 days and 1 year) and MCCR-PH (1 year) were the ones with ΔE values greater than the acceptability threshold. All other groups maintained their ΔE lower than the acceptability threshold after 1 year in distilled water. Regarding DC, there were no significant differences (p=0.127) among the materials. Non-significant negative correlations were observed between the mean ΔEab and DC (R=-0.65) and ΔE00 and DC (R=-0.64). A significant positive correlation was observed mean ΔEab and ΔE00 (R=0.99). It was concluded that the different luting agents influenced the final color of the restorations. The heating of the composite resins did not affect their DC.

Surface Deterioration of Indirect Restorative Materials.

The objective of this work was to evaluate the effects of in vitro and in situ biodegradation on the surface characteristics of two resin cements and a hybrid ceramic system. One hundred and eighty specimens (4X1.5mm) of each material (Maxcem Elite, NX3 Nexus and Vita Enamic) were made and randomly distributed in twelve groups (n=15) according to the material and biodegradation method. The specimens were then submitted to the following challenges: storage in distilled water 37 ºC for 24 h or 7 days, storage for 7 days, at 37 ºC, in stimulated saliva or in situ. The in situ stage corresponded to the preparation of 15 intraoral palatal devices, used for 7 days. Each device presented 3 niches, where a sample of each materials was accommodated. Specimens from both saliva and in situ groups suffered a cariogenic challenge, corresponding to the application of a solution of 20% of sucrose, 10 times throughout each day. After each biodegradation method, the surface roughness (Ra), Vickers hardness (VHN) and scanning electron microscopy (SEM) analyzes were performed. The data collected were evaluated by Levene test, two-way ANOVA and Tukey`s test (α=5%). The in situ challenge promoted the greater biodegradation, regardless of the material. Regarding the materials, the Vita Enamic VHN was negatively affected by all biodegradation methods and the Nexus NX3 presented better performance than the self-adhesive cement tested. Therefore, within the conditions of this work, it was concluded that in situ biodegradation can affect negatively the surface characteristics of indirect restorative materials.

Esthetic Rehabilitation with Direct Composite Resin in a Patient with Amelogenesis Imperfecta: A 2-Year Follow-Up.

Amelogenesis imperfecta is a group of conditions caused by over 15 different genes that affects the development of dental enamel and poses some challenges to dentists. An adult patient with amelogenesis imperfecta with severe changes in tooth color and reduction of occlusal vertical dimension sought dental treatment. Diagnostic wax-up was carried out to guide the stratification of a nanoparticulate resin for the restorative treatment. Direct composite resin restorations were applied on all teeth for modification of both esthetics and occlusion. After a 2-year follow-up, the findings appear to suggest that composite resin is a low-cost alternative when compared with indirect ceramic restorations, provides a good esthetic outcome, and offers considerable longevity for cases like the one reported herein.

Cara smile: Use of planning software to facilitate esthetic dental treatment in a case.

Treatment of the anterior teeth is challenging. Computer resources and software are available to facilitate a digital smile approach, thus allowing the dentist to plan and predict an esthetic result for a patient, particularly when an integrated multidisciplinary approach is necessary. Digital smile design has emerged as a tool in cosmetic dentistry that helps both professionals and the patient to visualize the result, in addition to facilitating a discussion between the two before establishing a final treatment decision. Here, we present a case involving a 27-year-old female who underwent multidisciplinary treatment initiated by digital planning using specific software, namely Cara Smile. The patient presented with complaints of maxillary tooth malalignment, staining, and fractures. To obtain the correct width-to-height ratio, a simulated gingival procedure was performed in the software. Gingivectomy was performed using digital simulation, and 90 days after surgery, cast and wax-up models maintaining the previously planned width-to-height ratio for the maxillary anterior teeth were made. Esthetic crowns and veneers were fabricated using the digital planning protocol. Therefore, Cara Smile is useful to facilitate the diagnosis through digital photos, improve communication between the various professionals involved in treatment, and guide the predictability of treatment and patient acceptance.

Clinical Steps for Restoration of Fractured Anterior Teeth: Color Protocol with Non-VITA Scale.

Direct composite resin restorations are commonly provided because of their satisfactory esthetics and minimal wear of opposing tooth structure. Recent restorative systems may not follow the nomenclature of the classical VITA shade guide, using instead a simplified resin color system. A better understanding of these systems and their behavior regarding the incidence of light is an excellent approach to anterior restorations, especially for fractured anterior teeth. This paper demonstrates the color selection and clinical sequence for the natural reproduction of tooth structure using a resin system that does not follow the VITA classical scale.

Color stability of ceramic veneers as a function of resin cement curing mode and shade: 3-year follow-up.

The influence of curing mode and shade of resin cements on the color stability of minimum-thickness ceramic veneers after a three-year storage time in distilled water was evaluated in this study. Ninety-six 0.5-mm-thick feldspathic ceramic veneers (Mark II) were luted onto resin composite substrates (Filtek Z350 XT, shade A2E) with two light-cured (NX3 Light-cure and AllCem Veneer) and dual-cured resin cements (NX3 dual-cure and AllCem) in various shades. The specimens were stored in distilled water at 37°C. Color measurements were performed with a spectrophotometer at the following times: 1h and 24h; 7, 30, and 180 days; and 1, 2, and 3 years. Data for color difference (ΔEab) light-cured and dual-cured resin cements were analyzed by two-way ANOVA with repeated measures and Tukey's test (α = 0.05). For the light-cured cements, the ΔEab values were as follows: NX3-Yellow (2.37±1.35) = ACV-A1 (2.40±1.21) = ACV-Trans (2.52±1.46) = ACV-E-Bleach M (2.56±1.42) = NX3-White (2.69±1.49) = NX3-Clear (2.98±1.68). The lowest ΔE values were found for 1 h (0.61±0.36)a, followed by 24 h (1.15±0.55)b and 30 days (2.48±1.11)c. One year, 180 days, and 2 and 3 years presented higher ΔEab values (3.34±0.94, 3.52±1.04, 3.52±0.95 and 3.55±1.14, respectively)d. For the dual-cured cements, the ΔEab values varied as follows: NX3-Clear (2.32±1.24)a = NX3-Yellow (2.37±1.32)a = NX3-White (2.76±1.43)a < AC-Trans (3.77±1.91)b = AC-A3 (4.13±2.11)b < AC-A1 (5.38±2.92)c. Considering time, the lowest ΔEab values were found for 1 h (0.48±0.25)a, followed by 24 h (2.13 ±0.83)b, 30 days (3.54±1.31)c, and 180 days (3,70±1.73)c. The follow-up times of 1 (4.43±2.15)d, 2 (5.02±1.74)e, and 3 years (4.90±2.12)e presented higher ΔEab values. This study demonstrated that light-cured resin cements were less susceptible to color change than dual-cured cements. After 2 years of follow-up, all cements presented ΔEab values above the acceptability threshold.

Influence of Pre-Curing Different Adhesives on the Color Stability of Cemented Thin Ceramic Veneers.

The objective was to evaluate the color stability of thin ceramic veneers as a function of the curing mode (with and without pre-cure) of different adhesive systems applied to the internal surface of ceramics. Five adhesive systems (Scotchbond Multi-Purpose, Single Bond Universal, Gluma 2 Bond, Ambar, and Ambar APS) and photo-cured resin cement (Allcem Veneer) were used for cementing 0.6 mm-thick feldspathic veneers (Mark II) on composite resin substrates (Charisma Diamond). The groups, according to adhesive system, were divided into two subgroups (n=10): i) adhesive and resin cement were polymerized separately (pre-cure of the adhesive), ii) adhesive and resin cement were polymerized simultaneously. The CIELab color parameters were determined with a spectrophotometer at 24h (baseline), 7 days, 30 days and 12 months. Data were analyzed by two-way ANOVA and Tukey's test (α=0.05). The results indicated statistically significant differences for adhesive systems and time. The mode of curing of the adhesive system was not statistically significant: pre-cured adhesives (2.6±1.3) and not pre-cured adhesives (2.8±1.4). For the adhesives, ΔE values varied in the following order: Ambar-APS (1.6±0.5) < Scotchbond Multi-Purpose (2.6±1.2) = Gluma 2 Bond (2.7±1.2) = Ambar (2.9±1.2) < Single Bond Universal (3.5±1.5). For time, ΔE values were: 7 days (1.7±0.7), 30 days (3.5±1.2) and 12 months (2.9±1.3). It can be concluded that the different adhesive systems used for cementing thin ceramic veneers influenced the final color of the indirect restorations. The adhesives curing mode did not present a significant effect in the color stability of thin ceramic veneers.

Cutting efficiency of different diamond burs after repeated cuts and sterilization cycles in autoclave.

CONTEXT: The aim was to evaluate the cutting efficiency of different diamond burs after successive cuts and repeated sterilization in an autoclave. The morphology and grit sizes were analyzed and correlated to cutting efficiency. MATERIALS AND METHODS: Ten medium-grit diamond burs of five different manufacturers were investigated (KG, KG Sorensen; TH, Tri-Hawk; KM, Komet; HC, Heico; and FD, Frank Dental). Changes in the cutting efficiency of diamond burs on composite resin blocks were measured after five repeated cuts and after five sterilization cycles. Grit sizes were analyzed by scanning electron microscopy (SEM) and correlated to cutting efficiency. The data were statistically analyzed using 3-way ANOVA and Tukey's test (α = 0.05). RESULTS: Significant differences were observed for diamond burs (P < 0.0001) and condition (P < 0.0001). FD presented the lowest mean cut time (21.88s), followed by KM (36.08s). TH (40.18s), HC (41.65s), and KG (42.23s) had the highest cut times. The number of cuts was not statistically significant. New burs had a significantly shorter cutting time (33.38s) when compared with the ones after sterilization cycles (39.55s). A moderate to strong positive correlation was found between diamond size and cutting time (Pearson's coefficient of 0.77). CONCLUSION: All diamond burs demonstrated lower cutting efficiency after repeated autoclaving. Cutting efficiency did not decrease as the number of cuts increased.