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1.
Oper Dent ; 45(6): 664-676, 2020 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-32997740

RESUMEN

CLINICAL RELEVANCE: When a resin nanoceramic inlay is cemented using self-adhesive cement, a universal dentin adhesive can be applied to the prepared cavity. The application of the adhesive before self-adhesive cement placement provides similar or better interfacial adaptation than without the adhesive. SUMMARY: Purpose: The first objective of this study was to determine whether the luting material used for computer-aided design and computer-aided manufacture resin nanoceramic inlays affected interfacial adaptation. The second objective was to investigate whether application of a universal dentin adhesive before cementation affected interfacial adaptation. The final objective was to compare the inlay-side and dentin-side interfaces in the cement space.Methods and Materials: Seventy-four class I cavities were prepared on extracted human third molars. Cavities were optically scanned, and resin nanoceramic inlays were milled using Lava Ultimate blocks (3M ESPE). For the control groups, the fabricated inlays were cemented using Panavia V5 (Kuraray Noritake) or FujiCem 2 (GC). For the experimental groups, the teeth were randomly divided into groups I and II. Group I contained four subgroups using different luting materials; in all subgroups, the inlays were cemented and dual cured without pretreatment. Group II contained six subgroups in which inlays were cemented and dual cured after application of a universal dentin adhesive. After thermocycling, interfacial adaptation was measured using swept-source optical coherence tomography (SS-OCT) imaging and statistically compared among groups.Results: Interfacial adaptation was different depending on the luting material used (p<0.05). After application of a universal adhesive, some subgroups showed improved interfacial adaptation (p<0.05). In the comparison of inlay-side and dentin-side interfaces, no difference was found in interfacial adaptation (p>0.05).Conclusions: Interfacial adaptation for resin nanoceramic inlays differed with luting material. For some self-adhesive cements, application of a universal adhesive before cementation improved interfacial adaptation.


Asunto(s)
Incrustaciones , Tomografía de Coherencia Óptica , Resinas Compuestas , Diseño Asistido por Computadora , Preparación de la Cavidad Dental , Porcelana Dental , Humanos , Ensayo de Materiales , Cementos de Resina
2.
Int J Esthet Dent ; 15(3): 344-354, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32760928

RESUMEN

AIM: Die silicone materials are used to build chairside composite restorations. The purpose of this study was to compare the flowability, dimension accuracy, and tear strength of four elastomeric die materials. MATERIAL AND METHODS: Materials were divided into four groups: Mach-2 (M2), Scan Die (SD), GrandioSO Inlay System (GIS), and Impregum-F (IM). Flowability analysis was carried out using the shark fin test (SFT). For dimension accuracy, impressions were taken from a premolar Class I preparation and an elastomeric model was cast. Composite resin restorations were built and positioned into the premolar for gap measurement. The mean gap length was divided into three levels: acceptable (A), not acceptable (NA), and misfit (M). For tear strength, strip specimens were made with a V-shaped notch (n = 6). The specimens were tested in a universal machine until tear. All data were analyzed statistically with a confidence interval of 95%. RESULTS: GIS showed the lowest flowability values, with no differences between IM, M2, and SD. For dimension accuracy, IM showed 100% 'A' gap values, followed by M2 (80%), SD (60%), and GIS (60%). For tear strength, IM showed the highest values, followed by M2, GIS, and SD. CONCLUSIONS: M2, SD, and IM had similar flowability, while GIS had the lowest. IM presented higher tear strength than M2, followed by GIS and SD. IM showed the highest degrees of acceptable gap filling, followed by M2.


Asunto(s)
Resinas Compuestas , Incrustaciones , Análisis del Estrés Dental , Ensayo de Materiales
3.
J Prosthodont ; 29(8): 693-698, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32767417

RESUMEN

PURPOSE: This study was done to compare the survival rates of cast gold and ceramic onlays placed in a dental school setting. MATERIAL AND METHODS: An electronic search was conducted in the patient records at Adams School of Dentistry, University of North Carolina at Chapel Hill for onlay codes that were in the database (From 1998 until 2018). Progress notes and radiographs were scrutinized to establish the survival time of the restorations. Any complications that occurred during the life time of the restorations were noted. The survival was summarized by categorization based on ranges of survival time in years; group 1: 1 to 5 years, group 2: 6 to 22 years. The mean survival time and standard deviation were calculated. One-way ANOVA was used to determine whether there was a statistically significant difference in the survival times between gold and ceramic onlays. RESULTS: The mean survival rate of cast gold onlays (86.6%) was comparable to that of ceramic onlays (81.1%). The gold onlays in Group 1 had a higher mean survival time (2.43 years) than the ceramic onlays (2.03 years). This difference was statistically significant (p = 0.002). The ceramic onlays in Group 2 had a mean survival time of 19.75 years while gold onlays had a mean survival time of 17.63 years. This difference was not statistically significant (p = 0.91). CONCLUSION: It was concluded that while the survival rate of ceramic onlays (81.1%) was inferior to that of cast gold onlays (86.6%), it was comparable.


Asunto(s)
Oro , Incrustaciones , Cerámica , Porcelana Dental , Fracaso de la Restauración Dental , Humanos , Estudios Retrospectivos
4.
Int J Prosthodont ; 33(4): 410-417, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32639701

RESUMEN

PURPOSE: To evaluate the dimensional accuracy of impressions made using a new fast-setting polyether material. MATERIALS AND METHODS: A metallic reference model with two crown preparations, one inlay preparation, and three stainless steel precision balls was digitized to create a digital reference model. Sixteen one-step impressions were made for each of the four study groups, differing in impression material (regular-setting polyether [RSP] vs fast-setting polyether [FSP]) and technique (monophase vs dualphase), for a total of 64 specimens. Plaster casts fabricated from these impressions were digitized using 3D scans. Global accuracy was studied by evaluating distance and angle deviations between the replica and the reference model. Local accuracy was described in terms of trueness and precision of the aligned individual abutment tooth surfaces. RESULTS: For all impression materials and techniques, the local accuracy at the abutment tooth level was excellent. For surfaces prepared for crowns, mean trueness was < 10 µm, and mean precision < 12 µm. Inlay surfaces were associated with higher inaccuracies (mean trueness < 21 µm and mean precision < 37 µm). The greatest global inaccuracies were generally measured for the cross-arch span, with mean distance changes between -55 µm and -94 µm. For all aspects of studied accuracy, impressions with FSP were at least comparable to those fabricated with RSP. CONCLUSION: Within the limitations of this study, all tested polyether materials would allow for clinically acceptable impression making. The new fast-setting material could be an alternative to regular-setting polyether materials, especially for single crowns and small fixed partial dentures.


Asunto(s)
Técnica de Impresión Dental , Modelos Dentales , Coronas , Materiales de Impresión Dental , Incrustaciones
5.
Oral Maxillofac Surg ; 24(4): 411-415, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32556619

RESUMEN

PURPOSE: Various procedures have been adopted for eminence augmentation for treatment of recurrent temporomandibular joint dislocation. The aim of this study is to assess maximal incisal opening (MIO) using a custom-made titanium implant versus inlay autogenous augmentation from the patient's chin for more stable condylar movements. METHODS: Ten patients were treated in this study (20 joints) five patients with bilateral patient-specific titanium onlay implant and five for autogenous inlay grafting technique; each implant in the study group was virtually designed using a specific software and milled from titanium grade V blocks, then fixed with mini screws at the lateral aspect of the zygomatic arch while in the control group, autogenous corticocancellous bone block was harvested from the chin and wedged at the created defect of the eminence to increase its height. RESULTS: The follow-up period ranged from 6 months to 1 year to access the maximal incisal opening (MIO). The mean preoperative maximal incisal opening was 47.8 mm and that of the postoperative was 33.2 mm in the study group and 35.4 mm in the control group, respectively. One patient reported postoperative slight unilateral edema and pain that gradually diminishes after 1 month postoperative. CONCLUSION: No statistical difference between both groups p value 0.3.


Asunto(s)
Incrustaciones , Titanio , Trasplante Óseo , Humanos , Articulación Temporomandibular , Cigoma
6.
Quintessence Int ; 51(7): 566-576, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32500864

RESUMEN

OBJECTIVES: Long-term retrospective evaluation of the survival rate and the technical and biologic outcomes of all-ceramic inlays and onlays in premolars and molars. METHOD AND MATERIALS: Fifty-four patients treated as part of a prospective clinical trial and having received 157 inlays and 27 onlays made out of a leucite-reinforced glass-ceramic (IPS Empress) in premolars and molars, were invited to the present follow-up examination. The survival of the restorations was evaluated. The biologic outcomes were assessed by measuring the pocket probing depth (PPD), the Plaque Index (PI), and the Sulcus Bleeding Index (SBI). The technical behavior was evaluated using modified US Public Health Service criteria (modUSPHS). Finally, patient satisfaction was recorded with a questionnaire. Data of patients and restored teeth were analyzed descriptively, and continuous variables were given in mean values and standard deviations. For the analysis of the restoration survival over time, the Kaplan-Meier survival estimate was calculated. The level of statistical significance was set at P < .05. RESULTS: Thirty-six patients (20 women, 16 men; mean age 50.9 years) with 132 restorations, 107 inlays and 25 onlays, were examined after a mean observation time of 11.2 ± 4.3 years. The overall 11-year survival rate of the 132 restorations was 80.3%. Inlays exhibited an 11-year survival rate of 80.4% and onlays of 80.0%. Twenty-two technical complications occurred. Ceramic fractures (10.6%) and chipping (2.3%) were the most frequent complications. Six biologic complications occurred (4.5%). CONCLUSION: Glass-ceramic inlays and onlays presented favorable long-term clinical survival and success rates. Technical complications were predominant, and biologic problems remained rare. More clinical long-term data are needed.


Asunto(s)
Porcelana Dental , Incrustaciones , Cerámica , Fracaso de la Restauración Dental , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Estudios Retrospectivos
7.
Dent Mater ; 36(7): 854-864, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32473834

RESUMEN

OBJECTIVES: The purpose of the study was to compare the mvM stresses occurring in inlays, onlays and endocrowns made from different materials and their bonding with molars in a computer simulation of mastication. METHODS: The study was conducted using the finite elements method with contact elements. Sixteen 3D first molar models were created of a intact tooth - T; a tooth with a ceramic inlay - IN; a tooth with an onlay - ON; and a tooth with an endocrown - EN. The restorations were made of: Comp - resin nanoceramic; Hc - hybrid ceramic; Le - leucite ceramic; Dlit - lithium disilicate; and Zr - zirconia. Computer simulations of mastication were performed. The equivalent stresses according to the modified von Mises criterion (mvM) were calculated in model materials and contact stresses at the interface cement-dental tissue around the examined restorations. RESULTS: The highest equivalent mvM stresses were concentrated in buccal margins of inlays. The mvM stresses recorded in onlays were 1.6-5 times lower than those found in inlays, while in endocrowns they were 2.3-6.5 times lower. Around the onlays and endocrowns, in tooth structures and luting cement, mvM stresses were significantly lower compared to teeth restored with inlays. The tensile and shear contact stresses between inlays and teeth were several times lower than under another restorations. The highest stresses (58.5MPa) occurred in the zirconia inlay. The stresses observed in the enamel of a tooth restored with an INZr inlay were half those noted in INComp, and a third of those observed in cement. Tensile contact stresses at the interface between the INZr inlay and dental tissue were 4.5 times lower than in the INComp, and the shear stresses were more than 7 times lower. SIGNIFICANCE: The highest values and unfavorable of stress levels occurred in teeth restored with inlays. Cavities MOD in molars should be reconstructed with cusp-covering restorations. The endocrown in molars should withstand physiological loading. The higher the modulus of elasticity of the restoration material, the higher the stresses in the restorations, while the lower stresses were observed in the tooth structures, luting cement and at the interface between the restoration and the dental tissue. Ceramic restorations should provide better protection and marginal seal of the reconstructed tooth than composite ones.


Asunto(s)
Incrustaciones , Masticación , Resinas Compuestas , Simulación por Computador , Porcelana Dental , Análisis del Estrés Dental , Análisis de Elementos Finitos , Ensayo de Materiales , Diente Molar
9.
J Contemp Dent Pract ; 21(3): 296-303, 2020 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-32434978

RESUMEN

BACKGROUND: Short-fiber-reinforced resin composite (SFRC) is a direct bulk fill resin composite specially indicated in large complex cavities. It is characterized by having high fracture toughness and load bearing capacity to decrease the incidence of fracture of the restoration. MATERIALS AND METHODS: In two parallel groups (n = 38 restorations), 76 participants having complex proximal cavities with asymptomatic vital pulp were randomly enrolled in this trial and received either SFRC (Ever X Posterior, GC, Japan) covered by Gaenial posterior (GC, Japan) or chairside indirect restorations (Grandioso inlay system; VOCO, Germany) fabricated on a silicon die. Materials were applied according to the manufacturer instructions with the corresponding adhesive system. Only 67 participants completed the trial, which was assessed using the modified United States Public Health Service (USPHS) criteria by two independent blinded assessors at 6 months and 1 year follow-up visits. STATISTICAL ANALYSIS: Fisher's exact and Cochran's Q tests were used to analyze inter- and intragroup comparisons, respectively. The significance level was set at p ≤ 0.05. RESULTS: No statistically significant difference was observed between both tested groups for all USPHS criteria at different follow-up periods except for marginal integrity favoring the SFRC at 12 months when the difference became significant (p < 0.001), and color match favoring the nanohybrid indirect resin composite restorations with significant difference in scores at all follow-up intervals (p < 0.001) was found. Cochran's Q test showed significant differences within the same technique during the follow-up period for some criteria. CONCLUSION: Direct SFRC and indirect nanohybrid resin composite complex proximal restorations showed an acceptable clinical performance along the 1 year follow-up period. CLINICAL RELEVANCE: Direct SFRC restorations could be a viable treatment option for complex restorative cases.


Asunto(s)
Restauración Dental Permanente , Incrustaciones , Resinas Compuestas , Alemania , Humanos , Diente Molar , Estados Unidos
10.
Oper Dent ; 45(6): 608-617, 2020 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-32243253

RESUMEN

CLINICAL RELEVANCE: Using the deep margin elevation technique in preparations extending beyond the cemento-enamel junction appears to be beneficial in maintaining structural integrity of CAD/CAM-fabricated feldspathic ceramic inlays. SUMMARY: Objective: To evaluate the effect of deep margin elevation on structural and marginal integrity of ceramic inlays.Methods and Materials: Forty extracted human third molars were collected and randomly separated into four groups (n=10/group). In group 1 (enamel margin group), the gingival margin was placed 1 mm supragingival to the cemento-enamel junction (CEJ). In group 2 (cementum margin group), the gingival margin was placed 2 mm below the CEJ. In group 3 (glass ionomer [GI] margin group), the gingival margin was placed 2 mm below the CEJ, and then the margin elevated with GI to the CEJ. In group 4 (resin-modified glass ionomer [RMGI] margin group), the gingival margin was placed 2 mm below the CEJ, and then the margin elevated with RMGI to the CEJ. Standardized ceramic class II inlays were fabricated with computer-aided design/computer-aided manufacturing and bonded to all teeth, and ceramic proximal box heights were measured. All teeth were subjected to 10,000 cycles of thermocycling (5°C/55°C) and then underwent 1,200,000 cycles of vertical chewing simulation at 50 N of force. Ceramic restorations and marginal integrity were assessed with a Hirox digital microscope. The Fisher exact test (two-tailed) with adjusted p-values (α=0.05) and logistic regression were used for statistical analysis.Results: The cementum margin group had a significantly higher ceramic fracture rate (90%) compared to other groups (10% in enamel margin and GI margin groups, p=0.007; 0% in RMGI group, p<0.001). Logistic regression showed that with increased ceramic proximal box heights, the probability of ceramic fracture increased dramatically.Conclusion: Deep marginal elevation resulted in decreased ceramic fracture when preparation margins were located below the CEJ. There was no difference found between margin elevation with GI or RMGI. Increased heights of ceramic proximal box may lead to an increased probability of ceramic fracture.


Asunto(s)
Cerámica , Incrustaciones , Resinas Compuestas , Diseño Asistido por Computadora , Esmalte Dental , Porcelana Dental , Humanos , Cuello del Diente
11.
Clin Oral Investig ; 24(10): 3457-3466, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31989370

RESUMEN

OBJECTIVE: The objective of this in vitro study was to investigate fracture load, fracture types, and impact of chewing simulation of human molars restored with 3D printed indirect polyetheretherketone (PEEK) inlays and compare these with milled indirect PEEK inlays, direct resin composite fillings, and sound teeth. MATERIALS AND METHODS: A total of 112 molars with form congruent class I cavities were restored with (n = 16/group) 3D printed indirect PEEK inlays via fused layer manufacturing (FLM): (1) Essentium PEEK (ESS), (2) KetaSpire PEEK MS-NT1 (KET), (3) VESTAKEEP i4 G (VES), (4) VICTREX PEEK 450G (VIC), (5) milled indirect PEEK inlays JUVORA Dental Disc 2 (JUV), and (6) direct resin composite fillings out of Tetric EvoCeram (TET). Sound teeth (7) acted as positive control group. Half of the specimens of each group (n = 8) were treated in a chewing simulator combined with thermal cycling (1.2 million × 50 N; 12,000 × 5 °C/55 °C). Fracture load and fracture types of all molars were determined. Statistical analyses using Kolmogorov-Smirnov test and two-way ANOVA with partial eta squared (ηp2) followed by Scheffé post hoc test, chi square test and Weibull modulus m with 95% confidence interval were computed (p < 0.05). RESULTS: ESS and TET demonstrated the lowest fracture load with a minimum of 956 N, whereas sound molars showed the highest values of up to 2981 N. Chewing simulation indicated no impact (p = 0.132). With regard to Weibull modulus, KET presented a lower value after chewing simulation than JUV, whereas TET had the highest value without chewing simulation. All indirect restorations revealed a tooth fracture (75-100%), direct resin composite fillings showed a restoration fracture (87.5%), and 50% of the sound teeth fractured completely or had cusp fractures. CONCLUSIONS: All 3D printed and milled indirect PEEK inlays as well as the direct resin composite fillings presented a higher fracture load than the expected physiological and maximum chewing forces. CLINICAL RELEVANCE: 3D printing of inlays out of PEEK via FLM provided promising results in mechanics, but improvements in terms of precision and esthetics will be required to be practicable in vivo to represent an alternative dental material.


Asunto(s)
Impresión Tridimensional , Resinas Compuestas , Análisis del Estrés Dental , Estética Dental , Humanos , Incrustaciones , Cetonas , Ensayo de Materiales , Polietilenglicoles , Cementos de Resina , Fracturas de los Dientes
12.
Artículo en Inglés | MEDLINE | ID: mdl-31562036

RESUMEN

Localized vertical bone defects within the anterior mandibular alveolar ridge frequently pose a unique challenge for functionally and aesthetically pleasing rehabilitation of this area. Causes for significant bone loss in this region may include periodontal disease, postextraction atrophy, trauma, and orthodontic treatment. In the presence of such a defect, ridge augmentation may be obligatory before installation of dental implants. Several surgical procedures, notably bone augmentation techniques, including guided bone regeneration, onlay bone grafting, and interpositional grafts, have been described. However, loss of a single incisor or a few incisors may render these methods complicated for surgical manipulation. In this article, we aim to report the outcome of 4 cases with localized vertical osseous deficits in the anterior mandible, treated by using a technique whereby we utilized the bony defect's margins through a vestibular approach to wedge inlay grafts without additional fixation or distraction hardware, thus overcoming the surgical difficulties and achieving a favorable outcome.


Asunto(s)
Pérdida de Hueso Alveolar/cirugía , Aumento de la Cresta Alveolar , Implantes Dentales , Trasplante Óseo , Implantación Dental Endoósea , Incrustaciones , Mandíbula/cirugía
13.
Oper Dent ; 45(1): 52-61, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31084532

RESUMEN

PURPOSE: The purpose of this study was to investigate the effect of four direct restorative materials that can be used in the proximal box elevation (PBE) technique. METHODS AND MATERIALS: Seventy-five molar teeth were randomly assigned to one of five groups (n=15): type II glass ionomer (GI), type II resin-modified glass ionomer (RMGI), resin-based composite (RBC), bulk-fill (BF) resin-based composite, and a control with no box elevation procedure. Specimens were prepared for a standard mesio-occlusal-distal, computer-aided design/computer-aided manufactured (CAD-CAM) resin, nanoceramic onlay with mesial cervical margins located 1 mm above the cementoenamel junction (CEJ) and distal cervical margins located 2 mm below the CEJ. PBE was used to elevate the distal margins to 1 mm above the CEJ in all groups except the control group. For the control group the onlay margin was placed directly on the prepared distal tooth structure without PBE. A Lava Ultimate CAD/CAM resin, nanoceramic onlay restorative was manufactured and bonded on all specimens with RelyX Ultimate adhesive resin cement. The quality of the tooth-PBE material and PBE material-onlay interface was evaluated with scanning electron microscopy using epoxy resin replicas before and after cyclic loading (100,000 cycles, 1.2 Hz at 65N and 37°C). In addition to margin quality, the fracture resistance of each group was measured using a universal testing machine. Fracture pattern was recorded by visual examination. The Levene test for homogeneity and the Welch analysis of variance were completed for fracture resistance and margin quality. A χ2 test was completed for break mode. RESULTS: For dentin margins, a statistically significant difference was detected between the RMGI and control groups at baseline (p=0.0442). All other groups-GI, RBC, and BF-showed no difference from the control at baseline (p>0.05). No statistical significance was observed among groups for post-cyclic fatigue (p=0.8735). For onlay margins, no statistical significance was observed among groups for pre-cyclic fatigue, post-cyclic fatigue, or change (p=0.9713, p=0.528, p=0.4385, respectively). No significant difference was observed for the fracture resistance among groups or for the type of break by material used (p=0.1593, p=0.77, respectively). CONCLUSION: Within the parameters of this study, after mechanical fatigue, the materials used for PBE: RMGI, RBC, and BF, did not influence results in terms of margin quality and fracture resistance. Therefore, collective findings suggest that these materials might be suitable for PBE procedures. Nevertheless, clinical caution is recommended with any PBE procedure and further testing of GI materials is needed.


Asunto(s)
Resinas Compuestas , Incrustaciones , Diseño Asistido por Computadora , Materiales Dentales , Análisis del Estrés Dental , Ensayo de Materiales , Diente Molar , Cementos de Resina
14.
J Esthet Restor Dent ; 32(2): 244-250, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31642587

RESUMEN

OBJECTIVE: To evaluate the clinical performance of hybrid ceramic inlay-onlay restorations over a 2-year period. CLINICAL CONSIDERATIONS: A total of 30 lithium disilicate glass ceramic (LDC; control group) and 30 hybrid ceramic (HC; test group) inlay/onlay restorations were performed in 14 patients. Clinical evaluations were performed after 1 week, 6 months, 1 year, and 2 years of cementation according to the modified United States Public Health Service (USPHS) criteria, gingival index, and plaque index. The Friedman test was used for the significant difference in time and Wilcoxon signed-rank test was used for the determination of differences. The clinical parameters, gingival and plaque indexes differences in time were analyzed with Chi-square test. No statistically significant difference (P > .05) was found between the two groups in the modified USPHS, gingival index, and plaque index evaluations, whether statistically significant differences were found within groups. The total survival rate was 100% for both groups after 2 years. CONCLUSION: Based on the 2-year data, the tested HC can be considered a reliable material for inlay/onlay restorations. CLINICAL SIGNIFICANCE: The results of this in vivo study suggest that both resin nanoceramic materials and LDC materials have been successfully incorporated in treatments of inlay and onlay restorations. Short-term results showed that resin nanoceramic materials can be counted as a good choice in inlay and onlay restorations in an effort to reduce the treatment time associated with ceramic firing processes.


Asunto(s)
Porcelana Dental , Incrustaciones , Cerámica , Diseño Asistido por Computadora , Estudios de Seguimiento , Humanos , Boca
15.
J Prosthet Dent ; 124(1): 88-93, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31672425

RESUMEN

STATEMENT OF PROBLEM: Although different preparation designs have been proposed for onlays fabricated by computer-aided design and computer-aided manufacturing (CAD-CAM), their effect on marginal adaptation is unclear. PURPOSE: The purpose of this in vitro study was to investigate the effect of tooth preparation designs on the marginal and internal adaptation of ceramic-reinforced composite resin CAD-CAM onlays. MATERIAL AND METHODS: A traditional preparation with a heavy chamfer on the functional cusp and a contrabevel on the nonfunctional cusp and a shoulder preparation with equal reduction on all cusps were used for mesial-occlusal-distal (MOD) onlay preparations. Ceramic-reinforced composite resin onlays were designed and milled based on the scanned prepared teeth. A digital silicone replica technique was used to determine marginal discrepancies between preparations and onlay restorations. A total of 100 numeric distances (representations of the fit in each region) were measured in 3 distinct regions: the buccal margin, lingual margin, and internal area. Independent Student t tests were used to determine significant differences (α=.05). RESULTS: Traditional preparation designs resulted in significantly smaller overall discrepancies (50.9 ±0.5 µm and 139.1 ±5.4 µm, P<.001) and smaller marginal discrepancies in the buccal (49.7 ±1.4 µm and 135.8 ±2.2 µm, P<.001) and lingual areas (47.1 ±1.0 µm and 133.4 ±1.1 µm, P<.001). CONCLUSIONS: The marginal adaptation of ceramic-reinforced composite resin CAD-CAM onlays was affected by the preparation design. The traditional preparation design offered better marginal adaptation; therefore, it is recommended in clinical practice.


Asunto(s)
Adaptación Marginal Dental , Incrustaciones , Resinas Compuestas , Diseño Asistido por Computadora , Coronas , Diseño de Prótesis Dental , Humanos , Preparación del Diente
17.
Int J Prosthodont ; 33(1): 22-28, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31860910

RESUMEN

PURPOSE: To evaluate the clinical performance of endodontically treated (ET) teeth restored with two different marginal forms of lithium disilicate glass-ceramic (LDG ceramic) onlays. MATERIALS AND METHODS: A total of 120 posterior teeth were prepared for onlays after ET. The occlusal surfaces of the teeth were removed 1.5 to 2 mm anatomically. Different marginal forms were employed depending on the thickness of the residual axis wall of each tooth: In Group S, a 1-mm shoulder was prepared when the remaining axis wall was > 2 mm (n = 50), and in Group B, a 20- to 30-degree bevel was prepared when the remaining axis wall was ≤ 2 mm (n = 70). The access of the pulp chamber was filled with resin, and 1.5 to 2 mm of the box morphology of the pulp chamber was preserved. The pressed LDG ceramic was applied to the fabricated onlays. The teeth and restorations were checked after 6, 12, and 24 months. All available restored teeth were assessed using modified United States Public Health Service criteria. RESULTS: During the observation period, no tooth fracture occurred. Neither tooth cracks nor secondary caries were observed in Group S or Group B. The 2-year survival rate of the teeth was 100%. Five fractured onlays were observed in Group S in the molar region, while all onlays in Group B were intact (P < .05). The survival rate of the onlays was 95.83%. CONCLUSION: The results demonstrate that LDG ceramic onlays can preserve ET posterior teeth with a highly satisfactory outcome, though the marginal form may affect the survival rate of the onlay.


Asunto(s)
Porcelana Dental , Incrustaciones , Cerámica , Fracaso de la Restauración Dental , Estudios de Seguimiento
18.
Int J Prosthodont ; 33(1): 48-55, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31860913

RESUMEN

PURPOSE: To investigate the marginal and internal adaptations of ceramic inlay restorations placed with immediate dentin sealing (IDS) vs delayed dentin sealing (DDS) procedures. MATERIALS AND METHODS: Mesial and distal Class II cavities were prepared in 12 extracted molar teeth, which were randomly allocated into six groups of 2 teeth each. Lava Ultimate inlays were fabricated and luted to the cavities using All-Bond universal adhesive system and eCEMENT dual-curing resin cement following IDS/immediate cementation (control groups 1 and 2), IDS/delayed cementation (groups 3 and 4), or DDS/delayed cementation (groups 5 and 6) protocols. Teeth in groups 2, 4, and 6 were subjected to thermocycling of 500 cycles between 5°C and 55°C after inlay cementation. Following staining with silver nitrate solution, the marginal and internal gap volumes were determined using microcomputed tomography images. Statistical analyses were conducted using independent t test and one-way analysis of variance followed by Tukey post hoc test (P < .05). RESULTS: Marginal gap volume for DDS (1.856 ± 0.323 mm3) was significantly higher than that of IDS immediately after inlay cementation (0.891 ± 0.281 mm3) (P = .025). Following thermocycling, the internal gap volume for DDS (0.838 ± 0.248 mm3) was significantly higher than that for IDS (0.098 ± 0.066 mm3) (P = .000), but the marginal gap volume of DDS (1.964 ± 0.956 mm3) was not significantly different from that of IDS (1.426 ± 0.725 mm3) (P = .622). CONCLUSION: Luted ceramic inlays have a superior marginal adaptation right after cementation and a superior internal adaptation after thermocycling when using the IDS technique compared to the DDS technique. However, marginal adaptation after thermocycling was not significantly different between the two techniques.


Asunto(s)
Incrustaciones , Cementos de Resina , Cerámica , Adaptación Marginal Dental , Dentina , Ensayo de Materiales , Microtomografía por Rayos X
19.
J Esthet Restor Dent ; 32(2): 193-203, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31393651

RESUMEN

OBJECTIVES: This investigation was a longitudinal, randomized clinical trial to measure the clinical performance of a nano-ceramic material (Lava Ultimate/3M) for chairside Computer Assisted Design/Computer Assisted Machining (CAD/CAM) fabricated restorations. MATERIALS AND METHODS: One hundred and twenty chairside CAD/CAM onlays were restored with a CEREC system randomly assigned to 60 leucite-reinforced ceramic (IPS EmpressCAD/Ivoclar Vivadent AGBendererstrasse 2FL-9494 SchaanLiechtenstein) onlays and 60 nano-ceramic (Lava Ultimate/3M) onlays. Equal groups of onlays were cemented using a self-etch and a total etch adhesive resin cement. The onlays were recalled for a period of 5 years. RESULTS: At 1 week postoperatively, 10% of the onlays cemented with both the self-etch and total etch adhesive resin cements were reported as slightly sensitive. However, all patients were asymptomatic by the 4th week without treatment. Four leucite-reinforced onlays and one nano-ceramic onlay fractured and required replacement. CONCLUSIONS: Adhesive retention with a self-etch or total etch cementation technique resulted in a similar clinical outcome with no reported debonds. The nano-ceramic onlays had a lower incidence of fracture compared to the leucite-reinforced ceramic onlays with both having a very low risk of fracture. Nano-ceramic onlays performed equally as well as glass ceramic onlays over 5 years of clinical service. CLINICAL SIGNIFICANCE: Ceramic materials have been a mainstay for chairside CAD/CAM restorations for the past 30 years and a new category of resilient ceramics with a resin matrix has been introduced reported to offer ceramic-like durability and esthetics with resin-like efficiency in handling. There are no long-term clinical studies on the performance of these materials. This is a 5-year randomized clinical trial on the performance of nano-ceramic onlays.


Asunto(s)
Porcelana Dental , Incrustaciones , Cerámica , Diseño Asistido por Computadora , Humanos , Estudios Longitudinales , Ensayo de Materiales , Cementos de Resina
20.
Oper Dent ; 45(2): 163-172, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31373887

RESUMEN

This study aimed to evaluate the marginal and internal adaptation of partial coverage crowns (ceramic onlays) fabricated with Press, CEREC BlueCam, and CEREC OmniCam systems, using two preparation designs and evaluating the internal discrepancies at different locations. Two phantom maxillary premolars (master teeth) received different preparation designs, with (BX) and without (NB) a modified occlusal box with round internal angles. Sixty IPS e-max ceramic restorations were fabricated with three systems: Press (n=20), CEREC BlueCam (n=20), and CEREC OmniCam (n=20). Both marginal and internal discrepancy width were measured by using a stereomicroscope at ×25 magnification. The data were evaluated statistically using analysis of variance followed by Tukey's Honestly Significant Difference test (α=0.05). The ceramic restorations fabricated with the Press system presented significantly smaller marginal and internal disadaptations than the BlueCam and OmniCam CEREC systems (p<0.0001). Regarding the preparation designs, preparation BX presented the smallest marginal discrepancies for all fabrication systems and larger internal discrepancies than for restorations fabricated with the Press system. The occlusal location presented a larger internal discrepancy compared with the axial locations. Although the three systems resulted in the fabrication of restorations within a clinically acceptable adaptation with marginal discrepancies below 100 µm, the Press system presented the smallest marginal and internal discrepancies. An improved marginal adaptation was observed in the preparation design with a modified occlusal box with rounded internal angles.


Asunto(s)
Adaptación Marginal Dental , Incrustaciones , Cerámica , Diseño Asistido por Computadora , Coronas , Porcelana Dental , Diseño de Prótesis Dental
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