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1.
J Esthet Restor Dent ; 36(7): 1020-1028, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38445806

RESUMEN

OBJECTIVE: Evaluate the color and translucency of a nanoceramic resin subjected to hygiene practices and immersion in coffee over time. MATERIALS AND METHODS: Specimens (n = 80, HT and LT, 0.5-mm thick) of a nanoceramic resin were obtained and were divided in groups according to the simulated oral hygiene: no intervention (NT), brushing with an electric brush and water (BN), brushing with an electric brush and toothpaste for 10 s (BT), and immersion in mouthwash for 30 s (MW). Oral hygiene practices were repeated after staining in coffee solution for 15, 48, 336, 1440, 8640, and 35,040 min. Spectral wavelengths were recorded with a spectrophotometer at each time. ∆E00, ∆L', ∆C', ∆H', and TP00 were calculated by CIEDE2000 and were evaluated by 2-way ANOVA, repeated measures ANOVA, and Tukey's HSD test (α = 0.05). RESULTS: ANOVA showed significance among factors for ΔE00 (p < 0.05), with higher ΔE00 for NT-HT (11.7) and NT-LT (11.2). After T6 (2-year simulation), the lowest values were found for BT-HT (5.3) and BT-LT (4.9). All groups showed a reduction in lightness and translucency and increased chroma and hue. However, the smallest variations were found in the BT groups (p < 0.05). CONCLUSIONS: Brushing with toothpaste effectively minimized the color change of NCRs caused by coffee staining. CLINICAL SIGNIFICANCE: Oral hygiene practices, such as brushing with toothpaste, might be important to minimize staining of nanoceramic resin restorations, especially in patients who frequently consume coffee.


Asunto(s)
Café , Color , Higiene Bucal , Cerámica/química , Humanos , Espectrofotometría , Cepillado Dental , Pastas de Dientes/química
2.
BMC Oral Health ; 24(1): 173, 2024 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-38308326

RESUMEN

BACKGROUND: Since color measurements are relative, the discrepancy among different instruments is alarmingly high. This multicenter study evaluated the effectiveness of instrument calibration and inter-instrument harmonization of different spectrophotometers with the same optical geometry using tooth-colored, translucent dental materials. METHODS: The coordinating center (CC) spectrophotometer was calibrated using the NPL Ceram Series II set. Two sets of 10 specimens, labeled 1 to 10 and I to X (10 mm in diameter and 1 mm thick), were tested at CC and three research sites (RS1, RS2, and RS3) using the same d/8° optical geometry spectrophotometers. Calibration factors were calculated for each material and site to obtain the average calibration factors for sets 1-10, set I-X, and the combination of both. The differences among the non-corrected and corrected reflection values were calculated using CIEDE2000 (DeltaE00) and CIELAB (DeltaEab) color difference formulas and were submitted to ANOVA and Tukey test (α = 0.05). RESULTS: A significant decrease of color differences between non-corrected as compared to corrected measurements was recorded for all CC-RS and RS-RS comparisons. The reduction of DeltaE00 values between non-corrected and corrected for CC-RS1, CC-RS2, and CC-RS3 were 83.1%, 77.2%, and 73.6%, respectively. The corresponding DeltaE00 values for RS1-RS2, RS1-RS3, and RS2-RS3 comparisons, indirectly compared in the experiment, were 84.2%, 82.8%, and 68.5%, respectively. There was a significant reduction of DeltaE00 and DeltaEab color difference for all combined RS pairs and each of three RS pairs, corrected with one of two specimen sets calibration factors separately. CONCLUSIONS: Calibration and harmonization of color measurements in dentistry using tooth-colored, translucent restorative materials significantly decreased measurement discrepancies between the coordinating center and research sites and among pairs of research sites.


Asunto(s)
Materiales Dentales , Odontología , Humanos , Color , Espectrofotometría , Ensayo de Materiales
3.
J Prosthet Dent ; 127(3): 498.e1-498.e8, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34973836

RESUMEN

STATEMENT OF PROBLEM: Whether color changes in resin nanoceramic (RNC) restorations can occur because of material and adhesive interface degradation is unclear. PURPOSE: The purpose of this in vitro study was to evaluate the color of RNCs submitted to surface treatments, cementation, and aging. MATERIAL AND METHODS: RNC specimens (N=120) were produced with a thickness of 0.5 mm. The No Treatment-High/Low Translucency (NT-HT/LT) groups did not receive treatments; the Airborne-particle Abrasion-High/Low Translucency (AA-HT/LT) groups were airborne-particle abraded, and the Airborne-particle Abrasion Silane-High/Low Translucency (AASIL-HT/LT) groups received airborne-particle abrasion and a silane agent. Single specimens (n=60) were measured on a spectrophotometer before and after aging (50 000 cycles). The other half was mounted on composite resin bases and measured. The cleaned specimens were cemented (C) on the bases and measured (T0 and T1). ΔE00, ΔL', ΔC', and ΔH' were obtained by using the CIEDE2000 formula and analyzed by using ANOVA and repeated-measures ANOVA. Multiple comparisons were made by using the Tukey HSD test (α=.05). RESULTS: For single specimens, the greatest ΔE00 values were observed in the AA-T1-LT resin (5.87). For mounted and cemented conditions, the greatest ΔE00 values were found in the AA-C-T1-LT resin (1.74), and the ΔE00 ranged from 0.75 (NT-OL) to 1.44 (AASIL-C-T1) for the HT resin (P<.001). The mounted and cemented specimens tended toward red and yellow, whereas lighter specimens were observed after cementation. CONCLUSIONS: Aging affected the color of the RNCs evaluated. The single specimens showed greater color differences than the cemented specimens, reinforcing the importance of the adhesive cement in the optical behavior of thin restorations.


Asunto(s)
Cementación , Cementos Dentales , Color , Resinas Compuestas , Cementos Dentales/uso terapéutico , Ensayo de Materiales , Cementos de Resina/uso terapéutico , Propiedades de Superficie
4.
J Prosthet Dent ; 128(3): 228-232, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33640088

RESUMEN

This clinical report describes the replacement of a traumatized maxillary canine that was extracted after unsuccessful orthodontic extrusion with an implant-supported restoration. Guided bone regeneration surgery was performed, followed by a second surgery with implant placement plus simultaneous bone and tissue regeneration. Esthetics and function were achieved with the placement of a veneered zirconia implant-supported restoration.


Asunto(s)
Implantes Dentales , Estética Dental , Diente Canino/cirugía , Prótesis Dental de Soporte Implantado , Maxilar/cirugía , Extrusión Ortodóncica
5.
J Prosthodont ; 31(S1): 105-135, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35313027

RESUMEN

PURPOSE: To screen and critically appraise available literature regarding additive manufacturing technologies for bone graft material fabrication in dentistry. MATERIAL AND METHODS: PubMed and Scopus were searched up to May 2021. Studies reporting the additive manufacturing techniques to manufacture scaffolds for intraoral bone defect reconstruction were considered eligible. A narrative review was synthesized to discuss the techniques for bone graft material fabrication in dentistry and the biomaterials used. RESULTS: The databases search resulted in 933 articles. After removing duplicate articles (128 articles), the titles and abstracts of the remaining articles (805 articles) were evaluated. A total of 89 articles were included in this review. Reading these articles, 5 categories of additive manufacturing techniques were identified: material jetting, powder bed fusion, vat photopolymerization, binder jetting, and material extrusion. CONCLUSIONS: Additive manufacturing technologies for bone graft material fabrication in dentistry, especially 3D bioprinting approaches, have been successfully used to fabricate bone graft material with distinct compositions.


Asunto(s)
Materiales Biocompatibles , Bioimpresión , Materiales Biocompatibles/uso terapéutico , Odontología , Impresión Tridimensional
6.
J Esthet Restor Dent ; 33(7): 999-1009, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-33929073

RESUMEN

OBJECTIVES: To assess the discoloration of teeth treated with the different phases of calcium aluminate cement (CAC), in comparison with the conventional CAC and mineral trioxide aggregate (MTA). MATERIALS AND METHODS: Fifty bovine incisors were prepared and filled. Two millimeters of the filling was removed to fabricate a cervical plug with the following cements (n=10): CA(CaO.Al2 O3 ); CA2 (CaO.2Al2 O3 ); C12 A7 (12CaO.7Al2 O3 ); CAC and MTA. The initial color measurement was performed and after 7, 15, 30, 45, 90, 180, and 365 days new color measurements were performed to determine the color (ΔE00 ), lightness (ΔL'), chroma (ΔC'), hue differences (ΔH'), and the whiteness index (WID ). RESULTS: ΔE00 was significant for groups (p = 0.036) and periods (p < 0.05). The greater ΔE00 was observed after 365 days for CAC (12.8). C12 A7 (7.2) had the smallest ΔE00 . ΔL' and ΔC' were significant for groups and periods (p < 0.05). ΔH' was significant for periods (p < 0.05). After 365 days, significant reduction in lightness was observed for all groups. For CA, CA2 , CAC, and MTA groups, the WID values decreased over time (p < 0.05). CONCLUSIONS: The tested cements changed the color behavior of the samples, resulting in greater teeth darkening over time. CLINICAL SIGNIFICANCE: There is no long-term study assessing the discoloration induced by the different phases of CAC.


Asunto(s)
Decoloración de Dientes , Compuestos de Aluminio/efectos adversos , Animales , Compuestos de Calcio/efectos adversos , Bovinos , Color , Cementos Dentales/efectos adversos , Materiales Dentales , Combinación de Medicamentos , Óxidos/efectos adversos , Silicatos/efectos adversos , Decoloración de Dientes/inducido químicamente
7.
J Prosthet Dent ; 125(2): 323.e1-323.e7, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33176924

RESUMEN

STATEMENT OF PROBLEM: Marginal fit of zirconia restorations is an important criterion for their long-term success. However, in spite of the wide use of zirconia in dentistry, the relationship between marginal fit and low-temperature degradation from aging is unclear. PURPOSE: The purpose of this in vitro study was to compare the marginal adaptation of veneered and monolithic zirconia and metal-ceramic computer-aided design and computer-aided manufacturing (CAD-CAM) crowns before and after cementation and to evaluate the influence of artificial aging on the adaptation of zirconia crowns. MATERIAL AND METHODS: Seventy-two standardized dies were prepared to receive a posterior crown and randomly divided into 6 groups (n=12) as per the material and the presence or not of cement: metal-ceramic, veneered zirconia, and monolithic zirconia. The zirconia groups were subjected to accelerated low-temperature degradation through hydrothermal aging in an autoclave at 131 °C and 0.17 MPa for 5 and 20 hours. A scanning electron microscope with a magnification of ×1000 was used for marginal adaptation measurements, and X-ray diffraction (XRD) was used to characterize phase transformation degradation. The data were statistically analyzed using 2-way ANOVA, repeated measures ANOVA with Greenhouse-Geisser correction, and the t test (α=.05). RESULTS: No significant differences in the marginal discrepancy were recorded among the analyzed groups. The presence of cement did not influence marginal fit in any treatment group. No significant differences were observed in the marginal adaptation values before and after aging (P>.05). After 20 hours of aging, the monoclinic phase increase to 8.3% on veneered zirconia and to 3.1% on monolithic crowns. CONCLUSIONS: Monolithic and bilayer CAD-CAM zirconia crowns showed marginal gaps that were within an acceptable range of clinical discrepancy, regardless of cementation. Marginal adaptation was not influenced by aging. Low-temperature degradation did not lead to a significant transformation from the tetragonal to monoclinic phase.


Asunto(s)
Cementación , Adaptación Marginal Dental , Cerámica , Diseño Asistido por Computadora , Coronas , Porcelana Dental , Diseño de Prótesis Dental , Circonio
8.
J Contemp Dent Pract ; 22(1): 101-104, 2021 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-34002718

RESUMEN

AIM: This clinical technique report aimed to describe a composite resin repair technique performed in an implant-supported prosthesis. BACKGROUND: Veneering ceramic fracture or chipping is one of the most frequent clinical failures in dentistry. Therefore, the use of less time- and cost-consuming ceramic repair techniques is helpful in clinical practice. TECHNIQUE: Briefly, to treat the ceramic surface, the glaze was removed at the margins of the fracture area, then, air-abrasion and acid-etching were performed. To promote chemical adhesion, a silane coupling agent and adhesive system were applied over the ceramic surface, and the composite resin was applied by incremental technique. Finally, the polish was performed. CONCLUSION: In conclusion, the applied composite resin repair of feldspathic porcelain chipping in implant-supported prosthesis was a simple, easy, affordable, and minimally invasive treatment. CLINICAL SIGNIFICANCE: The causes of veneer materials failures in metal-ceramic crowns are considered a challenge for the dentist and a problem that displeases patients. Repairs are indicated to prevent cracks from spreading and to prevent the accumulation of biofilm on the damaged surface. Therefore, different repair protocols have been proposed to enhance the esthetic, functionality, and longevity of the implant-supported prosthesis. Additionally, the success of the clinical cases depends on the capability to identify ceramic failures and the ability to indicate/perform the correct repair protocol. Since the described repair technique of the fractured screw-retained implant-supported prosthesis was a simple, easy, affordable, and minimally invasive treatment, with excellent esthetic and masticatory results, it represents an interesting clinical option.


Asunto(s)
Implantes Dentales , Porcelana Dental , Tornillos Óseos , Coronas , Prótesis Dental de Soporte Implantado , Fracaso de la Restauración Dental , Estética Dental , Humanos , Circonio
9.
J Esthet Restor Dent ; 31(5): 514-519, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31497927

RESUMEN

OBJECTIVE: Defects/bubbles can occur during the manufacture of bis-acryl resin provisional restorations, requiring repair or new prosthesis. This study evaluated the color stability of bis-acryl resin specimens repaired, aging, and immersioned in beverages. MATERIAL AND METHODS: Eighty disks were made of bis-acryl resin. Twenty disks were not repaired (BCR), 20 disks were repaired with the same bis-acryl resin (BCR-BCR), 20 disks were repaired with flowable resin (BCR-FR), and 20 disks received an adhesive layer prior to flowable resin repair (BCR-AFR). Coordinates L*a*b* were obtained. Ten disks from each group were thermocycled (5000 cycles) and the others were immersed in coffee with sugar (n = 5) and cola-based soft drinks (n = 5) for 7 days. Color, lightness, chroma, and hue differences were calculated by the CIEDE2000 formula, analyzed by two-way analysis of variance. Multiple comparisons were made with the Tukey's HSD test (α = .05). RESULTS: BCR-FR group presented the highest color differences (5.6) between groups repaired (P < .001). BCR-BCR group showed the smallest color differences (0.9) after aging (P = .003), but the greatest variation between T0 and T1 (about 1 ΔE). BCR-ARF immersed in coffee showed the greatest color differences (20.6) (P < .001). CONCLUSIONS: Aging and immersion altered the colorimetric behavior of repairs, especially after the use of coffee. CLINICAL IMPLICATIONS: Repairs are indicated when defects and bubbles are present in the surface of the bis-acryl resin provisional restorations after its manufacture. However, they may present noticeable color changes, especially when the use of coffee is frequent.


Asunto(s)
Resinas Acrílicas , Resinas Compuestas , Bebidas , Color , Ensayo de Materiales , Propiedades de Superficie
10.
J Esthet Restor Dent ; 31(6): 533-541, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31268244

RESUMEN

OBJECTIVE: The unavoidable extraction of teeth in the esthetic area can be overcome through different treatment modalities. Recently, immediate implants appeared as a minimally invasive approach to resolving these cases; however, immediate implant loading is not always possible or indicated. In these cases, an innovative approach through customized healing abutments could be used to preserve the soft tissue contour, eliminating the need for reopening surgery and the use of provisional restorations to condition the mucosal contour. CLINICAL CONSIDERATIONS: The present cases describe a simplified chairside approach to use customized healing abutments for immediate implants placed after tooth extraction in the anterior and posterior areas in order to maintain the soft tissue contours while reducing the clinical steps until delivering the final restorations. CONCLUSIONS: This technique seems to be effective to guide the soft tissue healing around dental implants allowing a natural emergence profile with implant-supported restorations, reducing the number of treatment steps. CLINICAL SIGNIFICANCE: The use of customized healing abutments prepares soft tissue for the prosthetic stage preserving its contours and eliminating the need for reopening surgery.


Asunto(s)
Implantes Dentales de Diente Único , Implantes Dentales , Carga Inmediata del Implante Dental , Pilares Dentales , Implantación Dental Endoósea , Prótesis Dental de Soporte Implantado , Humanos , Extracción Dental
11.
J Esthet Restor Dent ; 31(4): 299-303, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-30912240

RESUMEN

OBJECTIVE: This article presents a retrospective analysis of an anterior single crown that showed chipping of the veneering ceramic, the clinical stages of intraoral repair made in composite resin, and fractographic analysis of the causes of failure. CLINICAL CONSIDERATIONS: The ceramic chipping occurred in the incisal and labial surfaces of the crown, 1 year after installation. Clinical examination revealed the presence of occlusal interference, which was probably responsible for chipping. Vinyl-polysiloxane impression was made from the patient, and epoxy replica was produced. The replica was gold coated and inspected under the optical microscopy and scanning electron microscope (SEM) for descriptive fractography. Optical microscopy and SEM images showed that chipping initiated at the incisal edge, where it is possible to note an area of damage accumulation. At the labial surface, multiple arrest lines with their convex sides facing the incisal edge were observed. The fractured area was repaired intraorally with composite resin, and the patient's occlusion was checked and monitored. CONCLUSION: According to the fractographic analysis, occlusal interference was related to ceramic chipping in the incisal edge. Intraoral repair technique with composite resin was indicated for this moderate chipping. CLINICAL SIGNIFICANCE: Retrieval analysis of chipping ceramic delivers better understanding of the failure origin and could prevent future failures. Intraoral repair is a practical and conservative technique and may be performed in a single clinical session without requiring the removal of prosthesis.


Asunto(s)
Fracaso de la Restauración Dental , Coronas con Frente Estético , Cerámica , Coronas , Porcelana Dental , Humanos , Ensayo de Materiales , Estudios Retrospectivos , Propiedades de Superficie
12.
J Esthet Restor Dent ; 31(4): 388-397, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31099974

RESUMEN

OBJECTIVE: Evaluate the adhesive behavior of conventional and high-translucent zirconia after surface conditioning and hydrothermal aging. MATERIALS AND METHODS: Conventional (ZrC) and high-translucent zirconia (ZrT) specimens were divided into six groups: without surface treatment (ZrC and ZrT), air-borne particle abrasion with 50-µm Al2 O3 sized particles (ZrC-AO and ZrT-AO), and tribochemical treatment with 30-µm silica modified Al2 O3 sized particles (ZrC-T and ZrT-T). Zirconia specimens were treated using an MDP-containing universal adhesive and bonded to two resins blocks with an adhesive luting cement. Microbar specimens with cross-sectioned areas of 1 mm2 were achieved. Half of the microbars were subjected to hydrothermal aging. Bond strength was evaluated by microtensile bond strength test and statistically evaluated by the Weibull analysis. RESULTS: Roughness of the ZrC-AO and ZrT-AO groups were statistically higher. Bond strength analysis revealed higher bond strength for ZrC-AO and ZrC-T groups compared to ZrT-AO and ZrT-T, respectively. Mixed failure was the most frequent for the mechanically treated groups, while no cohesive failures were obtained. CONCLUSION: Lower values of bond strength were obtained for the mechanically treated high-translucent zirconia groups when compared to their conventional zirconia counterparts. Mechanical surface treatment significantly improved the bond strength to conventional and high-translucent zirconia. CLINICAL SIGNIFICANCE: Mechanical surface treatment (air-borne particle abrasion or tribochemical treatment) associated with the use of universal adhesives containing MDP could provide a durable bonding to conventional and high-translucent zirconia.


Asunto(s)
Recubrimiento Dental Adhesivo , Materiales Dentales , Análisis del Estrés Dental , Ensayo de Materiales , Cementos de Resina , Estrés Mecánico , Propiedades de Superficie , Circonio
13.
J Esthet Restor Dent ; 31(1): 5-12, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30499164

RESUMEN

OBJECTIVE: Congenital absence of maxillary lateral incisors is a frequent clinical challenge which must be solved by a multidisciplinary approach in order to obtain an esthetic and functional restorative treatment. Noninvasive treatments, that are in accordance with the patients' expectations, should be the first therapeutic alternative. If the deciduous tooth is present, minimally invasive dental extraction followed by immediate dental implant placement and provisional restoration is indicated. In this restorative treatment, an adequate emergency profile can be achieved by peri-implant soft-tissue-conditioning techniques. Moreover, the association of restorative materials, such as composite resins and dental ceramics, provides more predictable esthetic results. CLINICAL CONSIDERATIONS: The present case report presents a rehabilitation of bilateral congenital absence of maxillary lateral incisors through a multidisciplinary approach. Dental implants, long-term provisional restoration, tooth bleaching, minimally veneered high-translucent monolithic zirconia crowns, feldspathic veneers, and composite restorations were used by the dental team to achieve the expected functional and esthetic outcomes. CONCLUSIONS: Different treatment modalities are available for the rehabilitation of congenital absence of teeth. However, it is important that a dental team consider performing minimally invasive treatments, as many of these treatments are done on young patients. CLINICAL SIGNIFICANCE: Patient-centered treatments involving minimally invasive approaches in a multidisciplinary environment would be appropriate in order to achieve predictable results.


Asunto(s)
Implantes Dentales , Incisivo , Resinas Compuestas , Coronas , Estética Dental , Humanos
14.
J Prosthet Dent ; 121(3): 547.e1-547.e7, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30661878

RESUMEN

STATEMENT OF PROBLEM: Infiltrated zirconia has promising mechanical properties. However, information about its optical behavior is scarce. PURPOSE: The purpose of this in vitro study was to evaluate the color and translucency of zirconia submitted to infiltration and aging. MATERIAL AND METHODS: Sixty zirconia disks were machined. Ten disks received no treatment (NT group), 10 disks were immersed in a coloring liquid (A2 group), and 10 disks were immersed in a fluorescent liquid (F group). The other 30 disks were submitted to the same treatments plus glass infiltration (NT+I, A2+I, and F+I groups). The coordinates L*, a*, and b* and the Y tristimulus values were obtained to calculate the color (ΔE00), lightness, chroma, and hue differences; the translucency parameter (TP); and the contrast ratio (CR) associated with the specimens. After aging in an autoclave for 4 hours (T1), new measurements were made. Two- and 3-way ANOVAs were used to analyze color differences, TP, and CR. The lightness, chroma, and hue differences were evaluated by a repeated measures ANOVA. Multiple comparisons were made with the Tukey honestly significant difference (HSD) test (α=.05). RESULTS: The greatest color differences were observed in the A2+I group (11.23 ΔE00) (P<.001). Aging affected the chroma of the colored groups (P=.013 and P=.001) but did not affect their translucency (P=.347 for TP and P=.132 for CR). The greatest TP values were found in the NT and NT+I groups (2.54 and 2.34, respectively), whereas the CR was equal to or close to 1 in all groups. CONCLUSIONS: Color differences were observed in the glass-infiltrated groups. The TP and CR were affected by infiltration. Aging did not influence the optical behavior of the specimens.


Asunto(s)
Cerámica , Porcelana Dental , Color , Ensayo de Materiales , Circonio
15.
J Esthet Restor Dent ; 30(5): 397-407, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-30375751

RESUMEN

OBJECTIVE: This review integrates published scientific information about the fluorescence of natural teeth, dental resins and ceramics, and the main methods of analysis and quantification presented in the literature. OVERVIEW: Fluorescence is an emission of light (photons) by a substance that has absorbed light of higher energy. In natural teeth, it is more intense in the dentin than in the enamel and presents a bluish-white color. In dental resins and ceramics, fluorescence is obtained by the incorporation of materials that contain rare-earth luminescence centers (more precisely lanthanide luminescence centers), which allows these artificial materials to simulate natural teeth in a more beautiful and vital-looking way. However, the lack of knowledge about this optical phenomenon on the part of professionals indicates the need for more scientific studies and dissemination on this topic. CONCLUSIONS: Aesthetic materials have variable spectral compositions and fluorescence intensities, which are not always compatible with natural teeth. The fluorescence of teeth and restorative materials can be influenced by several factors, such as aging, temperature, and bleaching. Several devices for fluorescence evaluation and quantification are used in studies under different methodologies, but the small number of studies on the subject make it difficult to compare their results. CLINICAL SIGNIFICANCE: Fluorescence is a fundamental optical property for aesthetic rehabilitations since its presence and intensity in the restorative materials allows achieving an aesthetic result much closer to reality. However, the fluorescent behavior of natural teeth and aesthetic restorative materials is not yet fully understood by researchers and clinicians. Greater understanding of this phenomenon will contribute to the selection, indication, and clinical use of these materials.


Asunto(s)
Materiales Dentales , Restauración Dental Permanente , Resinas Compuestas , Esmalte Dental , Dentina , Fluorescencia
16.
J Esthet Restor Dent ; 30(5): 449-456, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-30194894

RESUMEN

OBJECTIVE: To evaluate the color of a bis-acryl resin after polishing, aging, and colorants. MATERIALS AND METHODS: From the 140 disks obtained, 35 were not polished (NP), 35 were polished with 3-µm (3P), 35 with 3- and 1-µm (1P), and 35 with 3-, 1-, and 0.5-µm sized particles (05P). Five disks of each group were thermocycled for 20, 100, and 200 cycles. Sixty disks were thermocycled and kept in beverages (tea, wine, and coffee) after four cycles. Sixty disks were immersed in the beverages for 24 hours, a week, and a month. The coordinates L*a*b* were measured and the color differences were analyzed by ANOVA. The lightness, chroma, and hue differences were evaluated by repeated measures ANOVA. Comparisons were made with Tukey's test (α = 0.05). RESULTS: Similar behaviors were observed between 3P and 05P groups (1.53 and 1.95ΔE00 ) (P < .05). The NP group submitted to 200 cycles showed the biggest color differences (3.02) (P = .003). The greatest color differences were observed in the NP group submitted to immersion in coffee (8.30) and wine (7.93) (P < .05). CONCLUSIONS: The polished surfaces were the least stained. Coffee and wine provided the greatest color changes, both for baths and immersions. CLINICAL SIGNIFICANCE: Polishing of provisional surfaces restorations made of bis-acrylic resin is essential to minimize staining caused by aging and use of colorants, regardless of the particle size present in the polishing paste. The contact with coffee and red wine should be avoided, especially for clinical times greater than 1 week.


Asunto(s)
Resinas Acrílicas , Baños , Bebidas , Color , Resinas Compuestas , Pulido Dental , Ensayo de Materiales , Propiedades de Superficie
17.
J Prosthet Dent ; 120(2): 276-281, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29551373

RESUMEN

STATEMENT OF PROBLEM: Laboratory procedures, such as dipping in coloring and fluorescent liquids, can be used to improve the optical properties of zirconia. However, information is lacking on the effect of these liquids. PURPOSE: The purpose of this in vitro study was to evaluate the color differences and degree of fluorescence of zirconia (3Y-TZP) treated with coloring and fluorescent liquids before and after an accelerated aging protocol. MATERIAL AND METHODS: Forty disk-shaped specimens of 3Y-TZP were fabricated by milling and separated according to the laboratory treatment performed: white zirconia (control group); zirconia treated with coloring liquid (A2 group); zirconia treated with fluorescent liquid (fluorescent group); and zirconia treated with both liquids (A2 fluorescent group). The L*a*b* coordinates before aging (T0) were obtained with a spectrophotometer, and the degree of fluorescence was measured. The disks were subjected to accelerated aging for 1 hour (T1) and 5 hours (T2). Measurements were made before and after each time interval. Color differences (ΔE00) were calculated using the CIEDE2000 formula and analyzed by 2-way ANOVA. Lightness (ΔL'), chroma (ΔC'), and hue differences (ΔH') were analyzed by multivariate ANOVA. Degrees of fluorescence were obtained as percentages and were analyzed by 2-way ANOVA. Multiple comparisons were performed by the Tukey HSD test (α=.05). RESULTS: Color differences were observed when 3Y-TZP disks were treated with coloring (7.91 ΔE00), with fluorescent liquid (5.81 ΔE00), and with both liquids (5.52 ΔE00). Accelerated aging resulted in color differences in the T2 A2 group (6.74 ΔE00) and at both times evaluated in the fluorescent group (T1=8.59 ΔE00 and T2=8.47 ΔE00) (P<.001). In the A2 fluorescent group, the degree of fluorescence was not influenced significantly (P>.05). The use of fluorescent liquid influenced the degree of fluorescence in the fluorescent group (T0=20%). CONCLUSIONS: Significant differences in color, lightness, chroma, and hue were achieved in all tested groups before and after aging. The degree of fluorescence was statistically different only in the fluorescent group and was not influenced by accelerated aging.


Asunto(s)
Color , Colorantes Fluorescentes/química , Coloración de Prótesis , Circonio/química , Análisis de Varianza , Cerámica/química , Colorantes , Materiales Dentales , Porcelana Dental/química , Estética Dental , Humanos , Ensayo de Materiales , Análisis Multivariante , Espectrofotometría , Factores de Tiempo
18.
BMC Med Genet ; 18(1): 145, 2017 12 08.
Artículo en Inglés | MEDLINE | ID: mdl-29221435

RESUMEN

BACKGROUND: Arrhythmogenic cardiomyopathy (ACM) is an inherited genetic disorder, characterized by the substitution of heart muscle with fibro-fatty tissue and severe ventricular arrhythmias, often leading to heart failure and sudden cardiac death. ACM is considered a monogenic disorder, but the low penetrance of mutations identified in patients suggests the involvement of additional genetic or environmental factors. METHODS: We used whole exome sequencing to investigate digenic inheritance in two ACM families where previous diagnostic tests have revealed a PKP2 mutation in all affected and some healthy individuals. In family members with PKP2 mutations we determined all genes that harbor variants in affected but not in healthy carriers or vice versa. We computationally prioritized the most likely candidates, focusing on known ACM genes and genes related to PKP2 through protein interactions, functional relationships, or shared biological processes. RESULTS: We identified four candidate genes in family 1, namely DAG1, DAB2IP, CTBP2 and TCF25, and eleven candidate genes in family 2. The most promising gene in the second family is TTN, a gene previously associated with ACM, in which the affected individual harbors two rare deleterious-predicted missense variants, one of which is located in the protein's only serine kinase domain. CONCLUSIONS: In this study we report genes that might act as digenic players in ACM pathogenesis, on the basis of co-segregation with PKP2 mutations. Validation in larger cohorts is still required to prove the utility of this model.


Asunto(s)
Displasia Ventricular Derecha Arritmogénica/genética , Adulto , Anciano , Anciano de 80 o más Años , Oxidorreductasas de Alcohol/genética , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Proteínas Co-Represoras , Conectina/química , Conectina/genética , Distroglicanos/genética , Femenino , Humanos , Masculino , Persona de Mediana Edad , Modelos Moleculares , Mutación , Proteínas del Tejido Nervioso/genética , Linaje , Placofilinas/genética , Dominios Proteicos , Proteínas Represoras/genética , Secuenciación del Exoma , Proteínas Activadoras de ras GTPasa/genética
19.
J Prosthet Dent ; 117(4): 453-458, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27881329

RESUMEN

Patients with CHARGE syndrome (where CHARGE stands for coloboma of the iris or retina, heart defects or cardiac malformations, atresia/stenosis of the choanae, retardation of growth and development, genital anomalies, and ear abnormalities) present several orofacial anomalies. Their treatment depends on the specific type of manifestation. To perform the complex oral rehabilitation and achieve a conservative, esthetic, and functional exploration of the definitive treatment goal, computer-aided design and computer-aided manufacturing (CAD-CAM) polymers can be used as long-term interim restorations. This article reports the treatment of a young patient with CHARGE syndrome combined with oral alterations. CAD-CAM polymers offer an intermediate treatment with satisfying esthetics and function at low biological cost until bone growth is completed. This period facilitates additional planning for the definitive restoration.


Asunto(s)
Síndrome CHARGE/cirugía , Diseño Asistido por Computadora , Diseño de Prótesis Dental/métodos , Rehabilitación Bucal/métodos , Adolescente , Coronas con Frente Estético , Dentadura Parcial Fija , Estética Dental , Humanos , Masculino
20.
Mov Disord ; 31(12): 1901-1904, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27671522

RESUMEN

BACKGROUND: Linkage analyses of families with primary familial brain calcification (formerly idiopathic basal ganglia calcification [IBGC]) identified 3 candidate loci (IBGC1-3). Recently, SLC20A2 mutations were found in the IBGC1 and IBGC3 families, merging these 2 loci. We here elucidate the genetic cause of primary familial brain calcification in the 'IBGC2' kindred. METHODS: We sequenced known primary familial brain calcification genes and quantified SLC20A2 and PDGFB. Moreover, CT scans of affected and unaffected family members were evaluated by 2 blinded neuroradiologists for distribution of brain calcification. RESULTS: A heterozygous multiexonic SLC20A2 deletion was detected in several affected family members. A reevaluation of neuroimaging data revealed a subset of mutation-negative individuals with only mild and/or unilateral calcification. CONCLUSIONS: The identified SLC20A2 mutation resolves the genetic cause of primary familial brain calcification in the 'IBGC2' kindred, collapsing 'IBGC2' into IBGC1. We suggest an algorithm for predicting the chances of finding genetic mutations that has to be validated in further studies. Our study enhances criteria for the evaluation of neuroimaging data, contributing further to the much needed harmonization of diagnostic and research data collection in primary familial brain calcification. © 2016 International Parkinson and Movement Disorder Society.


Asunto(s)
Enfermedades de los Ganglios Basales/diagnóstico por imagen , Enfermedades de los Ganglios Basales/genética , Calcinosis/diagnóstico por imagen , Calcinosis/genética , Enfermedades Neurodegenerativas/diagnóstico por imagen , Enfermedades Neurodegenerativas/genética , Proteínas Cotransportadoras de Sodio-Fosfato de Tipo III/genética , Humanos , Linaje , Método Simple Ciego
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