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1.
J Adhes Dent ; 22(4): 343-351, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32666060

RESUMEN

PURPOSE: This randomized, split-mouth clinical study evaluated the marginal quality of direct class-I and class-II restorations made of microhybrid composite that were applied using two polymerization protocols and two marginal evaluation criteria. MATERIALS AND METHODS: A total of 50 patients (mean age: 33 years) received 100 direct class-I or class-II restorations in premolars or molars. Three calibrated operators made the restorations. After conditioning the tooth with 2-step etch-and-rinse adhesive, restorations were made incrementally using microhybrid composite. Each layer was polymerized using a polymerization device operated either in regular mode (600-650 mW/cm2 for 20 s) (RM) or high-power (1200-1300 mW/cm2 for 10 s) mode (HPM). Two independent, calibrated operators evaluated the restorations 1 week (baseline) and 6 months after restoration placement, and thereafter annually up to 10 years using modified USPHS and SQUACE criteria. Data were analyzed using the Mann-Whitney U-test (α = 0.05). RESULTS: Alpha scores (USPHS) for marginal adaptation (76% and 74% for RM and HPM, respectively) and marginal discoloration (70% and 72%, for RM and HPM, respectively) did not show significant differences between the two polymerization protocols (p > 0.05). Alpha scores (SQUACE) for marginal adaptation (78% and 74% for RM and HPM, respectively) and marginal discoloration (70% for both RM and HPM) were also not significantly different at the 10-year year follow-up (p > 0.05). CONCLUSION: Regular and high-power polymerization protocols had no influence on the stability of marginal quality of the microhybrid composite tested up to 10 years. Both modified USPHS and SQUACE criteria confirmed that regardless of the polymerization mode, marginal quality of the restorations deteriorated significantly compared to baseline (p < 0.05).


Asunto(s)
Resinas Compuestas , Adaptación Marginal Dental , Restauración Dental Permanente , Adulto , Diente Premolar , Estudios de Seguimiento , Humanos , Polimerizacion , Estados Unidos , United States Public Health Service
2.
Aust Endod J ; 44(3): 240-244, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29034579

RESUMEN

A comparison of the abilities of rotary versus reciprocating files to eliminate viable Enterococcus faecalis populations from the long oval root canals of extracted human teeth. Fifty teeth were contaminated and randomly distributed into two groups (n = 25 each): BT-RaCe group and WaveOne group. Two microbial samples were obtained from each tooth before (S1) and after (S2) instrumentation. The CFUs from the S1 and S2 measurements were calculated and compared between the groups. Both groups showed significantly fewer CFUs in the S2 samples (P < 0.001). In the S2 intragroup comparison, BT-RaCe resulted in significantly fewer CFUs than WaveOne (P = 0.010). In the direct comparison between the rotary multiple file shaping system and the reciprocating single-file system, the multiple file system was more efficient at reducing the microbiological load of viable E. faecalis from long oval root canals.


Asunto(s)
Infecciones por Bacterias Grampositivas/terapia , Pulpitis/terapia , Preparación del Conducto Radicular/métodos , Tratamiento del Conducto Radicular/métodos , Instrumentos Dentales , Enterococcus faecalis/patogenicidad , Humanos , Pulpitis/microbiología , Preparación del Conducto Radicular/instrumentación , Tratamiento del Conducto Radicular/instrumentación , Muestreo , Sensibilidad y Especificidad , Extracción Dental
3.
J Clin Exp Dent ; 9(1): e40-e45, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28149461

RESUMEN

BACKGROUND: Non carious cervical lesions associated to muscle hyperfunctions are increasing. Microhybrid resin composites are used to restore cervical abfractions. The purpose of this study was to investigate if resin composites modify tooth plaque, inducing an increment of cariogenic microflora and evaluate their effect, in vivo and in vitro, against S. mutans. MATERIAL AND METHODS: Eight abfractions were restored with two microhybrid resin composites (Venus, Heraeus-Kulzer® and Esthet-X, Dentsply®), after gnatological therapy, in three patients with muscle hyperfunctions. For each abfraction three samples of plaque were taken from the cervical perimeter: before the restoration, one week and three months after restoration. The samples were evaluated both by traditional microbiological methods and by Polymerase Chain Reaction (PCR). In vitro, disk-shaped specimens of the two composites were prepared to estimate the effects against pre-cultured S. mutans, after incubation at 37°C for 24h and assessed by a turbidimetric technique. RESULTS: In vivo no differences were found in plaque growth, for all samples, before and after restoration with both composites; in vitro, instead, a significant reduction of S. mutans growth was found between specimens of two composites (Mann-Whitney U-test p>0,06). CONCLUSIONS: In this study a relevant consideration was elicited: composite materials, in vivo, do not modify plaque composition of non carious cervical lesions to a potential cariogenic plaque. Key words:Abfraction, restoration, S. mutans, composite, class V.

4.
Aust Endod J ; 43(3): 110-114, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27808450

RESUMEN

Comparison of the ability of newly designed rotary files to eliminate viable Enterococcus faecalis populations from long oval root canals of extracted human teeth to that of the self-adjusting file (SAF). One hundred caries-free, single-rooted, long oval teeth were contaminated with E. faecalis. The teeth were randomly distributed into four groups (n = 25) as follows: G.1, manual; G.2, SAF; G.3, ProTaper Next; and G.4, BT-Race. Two microbial samples were obtained from each tooth with sterile paper points, (s1) before and (s2) after instrumentation. The relative reduction in colony-forming units (CFUs) from s1 to s2 measurements was calculated and compared among the groups using parametric Kruskal-Wallis one-way anova on ranks and Dunn's method (a = 0.05). The results indicated a descending order of the groups with regard to efficacy as follows: BT-Race, Next, SAF and manual. The statistical analysis showed that the relative percentage reduction (RR) of CFUs was lower in the manual group than in the other groups, while the SAF group showed a significantly lower RR than the BT-Race group (P < 0.05). The efficacy in reduction of the microbiological load of viable E. faecalis from long oval root canals was different between the tested endodontic systems.


Asunto(s)
Instrumentos Dentales , Cavidad Pulpar/microbiología , Enterococcus faecalis/aislamiento & purificación , Preparación del Conducto Radicular/instrumentación , Carga Bacteriana , Humanos , Técnicas In Vitro , Distribución Aleatoria
5.
Int J Esthet Dent ; 11(4): 494-504, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27730220

RESUMEN

The aim of this case report was to treat eight simultaneous recessions that caused an unesthetic smile in a 27-year-old orthodontically treated female patient and to restore the anterior maxillary teeth in the esthetic area. The treatment consisted of bilaminar mucogingival surgery with a palatine graft and a collagen matrix graft (Mucograft, Geistlich). At 24 months, complete root coverage was achieved in all treated sites, with an increase of keratinized tissue (KT), complete resolution of hypersensitivity, and a high level of esthetic satisfaction. This case report shows that it is possible to correct multiple unesthetic recessions in one stage thanks to the combination of a connective tissue graft (CTG), a collagen matrix graft, and a coronally advanced flap (CAF).


Asunto(s)
Estética Dental , Recesión Gingival/cirugía , Adulto , Femenino , Humanos
6.
Int J Esthet Dent ; 11(3): 314-36, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27433548

RESUMEN

Restorative procedures are accompanied by a reduction of tooth stability, a decrease of fracture resistance, and an increase in deflection of weakened cusps. The choice between a direct or an indirect restorative technique, mainly in posterior areas, is a challenge, and involves biomechanical, anatomical, functional, esthetic, and financial considerations. In this article, the pros and cons of direct restorations are examined, as well as an analysis of indirect restorations and an overview of dental ceramics. In particular, several clinical uses of lithium disilicate overlays with a circumferential adhesive ferrule effect are proposed: heavily compromised vital teeth with thin walls, cracked teeth, and endodontically treated molars. Clinical procedures are described step by step on the basis of data from scientific literature. In conclusion, the use of lithium disilicate in combination with adhesive technologies can lead to a more conservative, economic, and esthetic approach in the restoration of heavily compromised teeth.


Asunto(s)
Recubrimiento Dental Adhesivo , Porcelana Dental/química , Diseño de Prótesis Dental , Restauración Dental Permanente/métodos , Resinas Compuestas/química , Amalgama Dental/química , Recubrimiento Dental Adhesivo/métodos , Materiales Dentales/química , Fracaso de la Restauración Dental , Estudios de Seguimiento , Humanos , Diente Molar/lesiones , Diente Molar/patología , Fracturas de los Dientes/terapia , Preparación Protodóncica del Diente/métodos , Diente no Vital/terapia
7.
J Clin Exp Dent ; 7(1): e54-9, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25810842

RESUMEN

OBJECTIVES: The aim of this clinical trial was to evaluate posterior indirect composite resin restoration ten years after placement luted with two different procedures. STUDY DESIGN: In 23 patients 22 inlays/onlays (Group A) were luted using a dual-cured resin composite cement and 26 inlays/onlays (Group B) were luted using a light cured resin composite for a total of 48 Class I and Class II indirect composite resin inlays and onlays. The restorations were evaluated at 2 time points: 1) one week after placement (baseline evaluation) and 2) ten years after placement using the modified USPHS criteria. The Mann-Whitney and the Wilcoxon tests were used to examine the difference between the results of the baseline and 10 years evaluation for each criteria. RESULTS: Numerical but not statistically significant differences were noted on any of the recorded clinical parameters (p>0.05) between the inlay/onlays of Group A and Group B. 91% and 94 % of Group A and B respectively were rated as clinically acceptable in all the evaluated criteria ten years after clinical function. CONCLUSIONS: Within the limits of the study the results showed after ten years of function a comparable clinical performance of indirect composite resin inlays/onlays placed with a light cure or dual cure luting procedures. Key words:Light curing composite, dual curing composite, indirect composite restoration, inlays/onlays, clinical trial.

8.
Artículo en Inglés | MEDLINE | ID: mdl-25738342

RESUMEN

This study aimed to determine the effect of adhesive direct composite restorations, endodontic treatments, and fatigue treatments on the cuspal deflection of maxillary premolars subjected to different cyclic occlusal forces. Thirty intact maxillary second premolars were selected. Ten teeth were left untreated (group IN), 10 teeth were subjected to endodontic and restorative treatment (group FL), and the remaining 10 teeth were subjected to endodontic, restorative, and fatigue treatments (group FT). All teeth were subjected to 5 occlusal compressive loading forces (98, 147, 196, 245, and 294 N) with a universal testing device. A total of 15 experimental groups were obtained with 3 tooth conditions (IN, FL, FT) and 5 different occlusal loading values. Deflection amounts (µm) were measured with laser sensors and recorded, and obtained data were statistically analyzed with one-way analysis of variance at a significance level of .05. Mean cuspal deflection values (µm) and SDs of experimental groups ranged as follows: IN-98 (24.4 ± 19.8), IN-147 (34.8 ± 28.9), IN-196 (43.8 ± 34.7), IN-245 (54.5 ± 46.4), IN-294 (60.3 ± 50.6), FL-98 (56 ± 49.1), FL-147 (62.6 ± 49.6), FL-196 (72.4 ± 52.1), FL-245 (81.3 ± 56), FL-294 (92.2 ± 60.9), FT-98 (77.2 ± 80.9), FT-147 (83.4 ± 81.3), FT-196 (92.6 ± 83.7), FT-245 (102.7 ± 85.4), and FT-294 (124.2 ± 89.5). Mean values of three main experimental groups were as follows: IN (43.5 µm), FL (72.9 µm) and FT (96.0 µm). Significant differences were found between the three main groups and relevant subgroups (P < .001). Highest cuspal deflection values (CDV) were obtained in FT groups. Lowest CDV were obtained in IN groups. FL groups showed higher deflection values than IN groups. CDV increased progressively as the teeth were restored and subjected to fatigue treatment.


Asunto(s)
Diente Premolar , Tratamiento del Conducto Radicular , Humanos , Técnicas In Vitro , Maxilar
9.
Int J Esthet Dent ; 9(4): 490-505, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25289384

RESUMEN

The use of zirconia is an esthetic alternative to metal for implant-supported frameworks, and it has increased primarily for its high biocompatibility, low bacterial surface adhesion, high flexural strength and high mechanical features. The zirconia frameworks in fixed prosthetic restorations that are supported by implants is commonly covered with hand-layered overlay porcelain. This technical procedure is highly esthetic but it can cause some complications, such as porcelain fractures. The purpose of this article is to introduce an innovative approach to create an esthetic fixed ceramic implant restoration to minimize and facilitate the repair of the mechanical complications, by combining the adhesive-cementation of lithium disilicate full coverage restorations on implant screw-retained zirconia frameworks.


Asunto(s)
Recubrimiento Dental Adhesivo , Implantes Dentales , Materiales Dentales/química , Porcelana Dental/química , Prótesis Dental de Soporte Implantado , Retención de Dentadura , Circonio/química , Grabado Ácido Dental/métodos , Óxido de Aluminio/química , Cementación/métodos , Diseño Asistido por Computadora , Coronas , Grabado Dental/métodos , Diseño de Prótesis Dental , Diseño de Dentadura , Retención de Dentadura/instrumentación , Dentadura Completa , Dentadura Parcial Fija , Humanos , Cementos de Resina/química , Silanos/química , Dióxido de Silicio/química , Propiedades de Superficie
10.
Int J Esthet Dent ; 9(3): 426-35, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25126621

RESUMEN

PURPOSE: Marginal fit is valued as one of the most important criteria for the clinical quality and success of all-ceramic crowns. The aim of this in vitro study was to investigate the marginal fit of Lava Zirconia crown-copings on chamfer and shoulder preparations. METHODS: Two acrylic model teeth were selected to simulate the clinical preparations: one molar was prepared with a chamfer finish line (C) and one premolar was prepared with a rounded shoulder finish line (RS). Each resin model was duplicated 10 times using silicon-based impression material and poured in type IV dental stone for the fabrication of working dies. A total of 20 copings were divided into two groups (n = 10 for each finish line). Fifty measuring locations were chosen randomly along the margin on the dies and the gap width - vertical marginal discrepancy - was measured under a light microscope with a magnification of x100. Measurements were made without cementation. The mean marginal gap widths and standard deviations were calculated and a one-way analysis of variance (ANOVA) was performed for different types of preparations in order to detect differences (α = 0.05). RESULTS: The mean marginal gap was 30 ± 3 µm for the C group and 28 ± 4 µm for the RS group. The one-way ANOVA showed no statistical significant difference between the two groups (P = 0.23). CONCLUSIONS: Within the limitations of this study, the marginal discrepancies were all within the clinical acceptable standard set at 120 µm. Chamfer and shoulder preparations did not show differences regarding the gap dimension. CLINICAL SIGNIFICANCE: Bur design is an easily selected parameter before natural tooth preparation. Both tested finish lines are able to help clinicians in obtaining acceptable marginal fit values for the investigated zirconia copings.


Asunto(s)
Diseño Asistido por Computadora , Coronas , Adaptación Marginal Dental , Diseño de Prótesis Dental , Preparación Protodóncica del Diente/métodos , Diente Premolar , Cerámica/química , Materiales Dentales/química , Humanos , Diente Molar , Propiedades de Superficie , Circonio/química
11.
Case Rep Dent ; 2013: 387206, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23762642

RESUMEN

A case of implant-bone prosthetic rehabilitation, after the fracture of the maxillary central incisors, which had been treated with grafting of a bone substitute, is reported. This case was followed by the normal procedures of implantology within the traditional timeframe for bone regeneration. However, a barrier membrane was not used which shows that even along with the use of graft material a sufficient amount of bone could be achieved for a subsequent rehabilitation. Therefore, after a five-year follow-up period, osseointegration was maintained with no marginal bone loss.

12.
J Dent ; 41(5): 436-42, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23454329

RESUMEN

OBJECTIVES: This randomised, split-mouth clinical study evaluated the marginal quality of direct Class I and Class II restorations made of microhybrid composite and applied using two polymerisation protocols, using two margin evaluation criteria. METHODS: A total of 50 patients (mean age: 33 years) received 100 direct Class I or Class II restorations in premolars or molars. Three calibrated operators made the restorations. After conditioning the tooth with 2-step etch-and-rinse adhesive, restorations were made incrementally using microhybrid composite (Tetric EvoCeram). Each layer was polymerised using a polymerisation device operated either at regular mode (600-650 mW/cm(2) for 20s) (RM) or high-power (1200-1300 mW/cm(2) for 10s) mode (HPM). Two independent calibrated operators evaluated the restorations 1 week after restoration placement (baseline), at 6 months and thereafter annually up to 5 years using modified USPHS and SQUACE criteria. Data were analyzed using Mann-Whitney U-test (α=0.05). RESULTS: Alfa scores (USPHS) for marginal adaptation (86% and 88% for RM and HPM, respectively) and marginal discoloration (88% and 88%, for RM and HPM, respectively) did not show significant differences between the two-polymerisation protocols (p>0.05). Alfa scores (SQUACE) for marginal adaptation (88% and 88% for RM and HPM, respectively) and marginal discoloration (94% and 94%, for RM and HPM, respectively) were also not significantly different at 5th year (p>0.05). CONCLUSION: Regular and high-power polymerisation protocols had no influence on the marginal quality of the microhybrid composite tested up to 5 years. Both modified USPHS and SQUACE criteria confirmed that regardless of the polymerisation mode, marginal quality of the restorations deteriorated compared to baseline.


Asunto(s)
Resinas Compuestas/química , Adaptación Marginal Dental , Materiales Dentales/química , Restauración Dental Permanente/clasificación , Grabado Ácido Dental/métodos , Adulto , Diente Premolar/patología , Color , Luces de Curación Dental/clasificación , Recubrimiento Dental Adhesivo/métodos , Caries Dental/terapia , Femenino , Estudios de Seguimiento , Humanos , Curación por Luz de Adhesivos Dentales/instrumentación , Curación por Luz de Adhesivos Dentales/métodos , Masculino , Metacrilatos/química , Persona de Mediana Edad , Diente Molar/patología , Polimerizacion , Adulto Joven
13.
Am J Dent ; 24(1): 8-12, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21469400

RESUMEN

PURPOSE: To evaluate the degree of conversion (DC) of dual-curing materials used to lute glass-fiber posts in a simulated root canal polymerized by two different modalities. METHODS: Artificial root canals were used to simulate a clinical condition to lute 45 posts by three different dual curing luting cements (Calibra, Multilink Automix and Variolink II). Two light cure modalities were chosen for each luting cement: standard (S group) 400 mW/cm2 for 120 seconds and high-power (H group) 1200 mW/cm2 for 40 seconds. Raman spectra were collected at different positions in the post surface (1, 3, 5 and 7 mm from the coronal-most portion of the post covered in cement) and the percentage degree of conversion was computed. The data were analyzed using ANOVA and post-hoc Student-Neuman-Keuls t-test (P = 0.05). RESULTS: The DC of the tested luting composites decreased progressively while increasing the distance from the light tip. Regardless of the polymerization modality (H or S) applied. Conversely, the curing modality significantly influenced the DC of the tested materials, evidencing different responses to the same energy density: Calibra seemed to be less dependent on light-curing than the other tested materials, showing a constant behavior. Multilink Automix reached the highest DCs in the S group compared to the H mode. Variolink II showed an interesting drawback in DC at 7 mm when cured in the H model. Dual-cure materials show adequate monomer conversion but when the distance from the curing light increased, a variable, but significant lowering in conversion rate was observed. In addition, the time and power of curing appeared to be material-dependent and should be calibrated individually.


Asunto(s)
Resinas Compuestas/química , Recubrimiento Dental Adhesivo/métodos , Curación por Luz de Adhesivos Dentales/métodos , Técnica de Perno Muñón , Análisis del Estrés Dental , Vidrio , Dureza , Humanos , Ensayo de Materiales , Polimerizacion , Cementos de Resina
14.
J Adhes Dent ; 13(3): 279-86, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21246078

RESUMEN

PURPOSE: To determine, by means of a non-destructive experimental procedure, the effectiveness of adhesive restorations in reducing the cuspal deflection of endodontically treated premolars, with or without root canal fiber posts. MATERIALS AND METHODS: The cuspal deflection of ten sound, intact maxillary premolars was evaluated. A loading device induced deformation by axial force (ranging from 98 to 294 N) applied on the occlusal surface of teeth while laser sensors registered the amount of deflection. Once tested, teeth were endodontically treated and the marginal ridges were removed. The teeth were randomly divided into two groups and restored with: group 1) dual curing adhesive, flowable composite, and microhybrid composite; group 2) the same materials associated with root canal glass fiber post and composite cement. The cuspal deflection test was repeated with the same protocol after restorative procedures, allowing a direct comparison of the same samples. Statistical analysis was performed using ANOVA at a significance level of 0.05. RESULTS: Different average cuspal deflection was detected in the two groups: composite resin with post insertion resulted in lower deformation compared with composite alone. Mean deflection ranged from 3.43 to 12.17 µm in intact teeth, from 14.42 to 26.93 µm in group 1, and from 15.35 to 20.39 µm in group 2. ANOVA found significant differences (p = 0.02). CONCLUSION: Bonded composite restorations with fiber posts may be more effective than composite alone in reducing the cuspal deflection in endodontically treated premolars in which the marginal ridges have been lost.


Asunto(s)
Resinas Compuestas , Recubrimiento Dental Adhesivo , Restauración Dental Permanente/métodos , Técnica de Perno Muñón , Diente no Vital , Adolescente , Adulto , Análisis de Varianza , Diente Premolar , Análisis del Estrés Dental , Vidrio , Humanos , Ensayo de Materiales , Corona del Diente/fisiología , Adulto Joven
15.
J Dent ; 37(8): 610-5, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19450917

RESUMEN

OBJECTIVES: Adhesive luting of indirect restorations can be carried out employing dual- or light-curing materials. This in vitro study evaluated the degree of conversion (DC) of the materials employed in this procedure, seeking how the combination of time and power of curing applied during polymerisation, as well as the temperature of the light-curing composite, influenced the DC. MATERIALS AND METHODS: One hundred and eighty onlays of different thicknesses (2 mm, 3 mm, 4 mm) were luted with three different composites: two dual-curing cements (Variolink II and Calibra) and a light-curing composite (Venus). The same halogen lamp was used with three different modalities selected to provide a constant quantity of energy. The time/power combinations tested were 400 mW/cm(2) for 120 s, 800 mW/cm(2) for 60s and 1200 mW/cm(2) for 40 s. The light-curing composite was employed at room temperature and after preheating at 54 degrees C. Each sample was examined in three positions using the Micro-Raman Dilor HR LabRam spectrometer to evaluate the polymer conversion degree. The data were analysed using analysis of variance and the Student-Newman-Keuls test (p=0.05). RESULTS: The dual-curing materials showed average conversion percentages close to 64%, although onlays thickness clearly influence the degree of conversion, the light-curing composite showed satisfactory results only when onlays thickness was thin, however preheating significantly improved the performance of the light-curing composite under onlays of great thickness. CONCLUSIONS: Optimal luting of indirect restorations is clearly dependent from light source power, irradiation time and dual-cure luting cement or light-curing composite chosen. It should be calibrated for each material to acquire high DCs. Preheating of light-curing only composites allows for the materials to reach optimal conversion degrees.


Asunto(s)
Resinas Compuestas/química , Recubrimiento Dental Adhesivo/métodos , Adaptación Marginal Dental , Incrustaciones/métodos , Cementos de Resina/química , Resinas Compuestas/efectos de la radiación , Cementos de Resina/efectos de la radiación , Espectrometría Raman
16.
Eur J Esthet Dent ; 3(2): 186-96, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-19655531

RESUMEN

The purpose of the study was to evaluate the shear bond strengths (SBS) of two resin cements to intaglio surfaces of zirconia from two manufacturers after three surface treatment methods. Forty zirconia specimens from one manufacturer (Lava, 3M ESPE) and 40 zirconia specimens from another manufacturer (Cercon, Dentsply), each with system-specific intaglio surfaces, were randomly divided into four treatment groups (20 samples per group, 10 for each manufacturer): no treatment (No_T), sandblasting with 50microm Al2O3 (S_50), sandblasting with 110 microm al2O3 (S_110), and Rocatec silica coating and silanization (ESPE-Sil, 3M ESPE) (Roc). A 5-mm metal ring was fixed upon the zirconia and was filled with one of two different resin composite cements (RelyX Unicem, 3M ESPE and Panavia F 2.0, Kuraray). Samples were stored in distilled water at 37 degrees C for 7 days; SBS was evaluated using a universal testing machine. Values were calculated in MPa and the data were analyzed by ANOVA and Tukey HSD test (P < .05). In the Lava specimens, the three surface treatment methods tested did not increase the bond strength of Panavia compared to the control group (P = .195); using RelyX Unicem, S_50 and Roc, mean SBS values were significantly higher than values for No_T (S50 P = .0048; Roc P < .001). For Lava surfaces treated with Rocatec, there was a statistically significant difference between the two luting cements used (Unicem 11.39 +/- 2.19; Panavia 8.56 +/- 1.17; P = .002). Regarding the Cercon specimens, there was a significant difference between the Unicem and the Panavia control groups (No_T Unicem 1.48 +/- 1.19, No_T Panavia 4.60 +/- 2.75, P = .004). In conclusion, all surface treatments increased the bond strength of RelyX Unicem resin cement to both zirconia substrates. No statistically significant changes were found using Panavia on Lava. Sandblasting with 110 microm Al2O3 provided the highest bond strength for Panavia on Cercon.


Asunto(s)
Recubrimiento Dental Adhesivo , Porcelana Dental , Cementos de Resina , Itrio , Circonio , Análisis del Estrés Dental , Ensayo de Materiales , Resistencia al Corte , Propiedades de Superficie
17.
J Adhes Dent ; 9(5): 463-7, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18297827

RESUMEN

PURPOSE: To evaluate in vitro the bond strength at the adhesive interface between a quartz fiber post, different adhesive systems, and different composite cements. MATERIALS AND METHODS: Thirty extracted single-rooted teeth were endodontically treated and divided into three groups (n=10). Quartz fiber posts (DT Light-Post) were cemented with the following materials: group I: Prime & Bond NT + Self Cure Activator, and Calibra as luting cement; group II: Prime & Bond NT + Self Cure Activator, and UniFil Core; group III: UniFil Bond in combination with Unifil Core. The specimens were processed for the push-out test to evaluate bond strength at the root dentin-cement-post interface. They were sectioned along the long axis of the post into 1-mm-thick slices. A total of 60 sections was obtained from group I. Group II provided 67 slices, while group III provided 69. Loading was performed at a crosshead speed of 0.5 mm/min until the post segment was dislodged from the root section. RESULTS: There was no statistically significant difference between the three experimental groups. The mean bond strength obtained for group I was 9.81 +/- 5.40 MPa. For group II it was 12.06 +/- 6.25 MPa, and 9.80 +/- 5.01 MPa for group III. CONCLUSION: All the materials tested were similar in terms of providing satisfactory bond strength when used for luting fiber posts. However, Unifil Core may be advantageous since it can also be used as a core buildup material, which simplifies the clinical procedures.


Asunto(s)
Recubrimiento Dental Adhesivo , Recubrimientos Dentinarios , Dentina , Técnica de Perno Muñón , Cementos de Resina , Grabado Ácido Dental/métodos , Análisis de Varianza , Retención de Prótesis Dentales , Cavidad Pulpar , Análisis del Estrés Dental , Humanos , Ensayo de Materiales , Cuarzo , Estadísticas no Paramétricas
18.
Eur J Esthet Dent ; 2(2): 188-209, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-19655565

RESUMEN

Scientific progress in adhesive dentistry has led to more conservative techniques, both direct and indirect, to solve esthetic problems in anterior teeth. This article will discuss only indirect techniques, which are clearly superior in complex cases in which it will be difficult to recreate harmonious tooth shape and color. After reviewing the literature and highlighting the properties of this technique, the indications and benefits compared to the direct technique will be assessed. This is followed by a step-by-step description of operative procedures, from treatment planning to relining and polishing of the cemented adhesive restoration. The long-term success of veneers depends mainly on the tooth preparation, which should be confined to enamel, involve proximal contact areas, maintain the cervical enamel margin, and incorporate the incisal edge to increase veneer resistance and enable correct placement. Although no clinical follow-up similar to that of ceramic materials is available, the latest-generation resin composites offer interesting features. They can withstand mechanical stress, have excellent esthetic properties, and, most importantly, can be repaired intraorally without impairing their physicochemical and mechanical properties.


Asunto(s)
Resinas Compuestas , Recubrimiento Dental Adhesivo , Materiales Dentales , Coronas con Frente Estético , Resinas Compuestas/química , Cementos Dentales/química , Esmalte Dental/anatomía & histología , Hipoplasia del Esmalte Dental/terapia , Materiales Dentales/química , Pulido Dental/métodos , Diseño de Prótesis Dental , Estética Dental , Humanos , Incisivo/anomalías , Preparación del Diente/métodos
19.
Br Dent J ; 198(7): 447, 2005 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-15870815

RESUMEN

Over the last few years, the advancements made in the field of adhesive techniques have significantly modified operative techniques, from cavity preparation to final restoration. On one hand, a predictable bond between restoration and dental tissues allows us to operate with very conservative techniques, saving sound dental tissue; on the other hand, it must be considered that such procedures are not simple. Additionally, it is easy to observe that all of our everyday dental practice is strictly influenced by the type of material and techniques used. Knowing such procedures as well as adhesive mechanisms, quality of sound dental tissue and its conservation - both in vital and endodontically treated teeth - is now considered significantly relevant for restorative purposes.


Asunto(s)
Resinas Acrílicas/química , Resinas Compuestas/química , Poliuretanos/química , Materiales Dentales/química , Restauración Dental Permanente , Humanos , Incisivo , Diente Molar
20.
Am J Dent ; 17(4): 295-300, 2004 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-15478495

RESUMEN

PURPOSE: To determine, by means of a non-destructive experimental procedure, the extent to which tooth cusps are weakened by endodontic procedures and the effectiveness of adhesive bonding restoration in reducing cuspal deflection as a function of different restorative procedures. METHODS: A mechanically controlled loading device induced cuspal deflection by axial force (range 98-294 N) on an occlusal surface while LTS laser twin sensors registered the amount of deflection. Cusp deflection values, in microns, were recorded for each tooth. Thirty sound maxillary premolars teeth were sequentially evaluated in the following conditions: A) intact tooth; B) completion of endodontic and restorative procedures. Teeth were randomly divided into five groups and restored respectively with: A) amalgam (Dispersalloy); B) Spectrum TPH; C) Surefil; D) Esthet-X; E) Esthet-X + Dyract Flow. RESULTS: The average loading force needed to induce 1 microm cusp deflection was evaluated, for all groups, in intact teeth (range 49.52-58.76 N/microm) and in restored teeth (range 8.56 - 47.05 N/microm). Statistical analysis (ANOVA for repeated measures) has been performed. Mean structural recovery values after restorative treatment were 17% with amalgam, 60% with Spectrum TPH, 59% with SureFil, 54% with Esthet-X, and 99% with Esthet-X/Dyract.


Asunto(s)
Diente Premolar/fisiopatología , Resinas Compuestas/química , Amalgama Dental/química , Recubrimiento Dental Adhesivo , Corona del Diente/fisiopatología , Diente no Vital/fisiopatología , Adolescente , Adulto , Análisis de Varianza , Fuerza de la Mordida , Compómeros/química , Aleaciones Dentales/química , Elasticidad , Humanos , Tratamiento del Conducto Radicular , Diente no Vital/terapia
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