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1.
J Clin Exp Dent ; 11(9): e807-e813, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31636873

RESUMEN

Background: The aim of this study was to evaluate the distribution of stress in complete fixed mandibular prostheses with infrastructures (IE) fabricated with different materials and techniques, under compressive force. Material and Methods: A model of an edentulous mandible, which received five 4x11 mm external hexagon implants between the mental foramens, was fabricated. The groups were divided into: Group I - IE in nickel-chromium with an acrylic resin occlusal coating; Group II - IE in nickel-chromium with a ceramic occlusal coating; Group III - IE milled in zirconia with a ceramic coating. For the photoelastic methodology, 70 N axial loads were applied in three regions. Photographic images were taken and analyzed according to the number of high-intensity fringes. For the strain gauge methodology, the measurement of stresses was performed in two distinct regions. The same compression tests described earlier were then performed. The registered stress values were grouped in tables and submitted to two-factor variance analysis (ANOVA) and the Tukey test with 5% significance. Results: The results of the two methodologies demonstrated smaller stress values for Group I, when compared to the other groups. Conclusions: It was possible to conclude that the complete fixed prostheses, with infrastructures cast in metal and acrylic occlusal coating, demonstrated better biomechanical results. Key words:Dental implants, mandibular prosthesis implantation, biomechanics.

2.
J Prosthodont ; 28(6): 692-700, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31125155

RESUMEN

PURPOSE: To investigate the influence of nonthermal plasma (NTP) treatment on the tensile bond strength between heat-polymerized acrylic resin for ocular prostheses and silicone reliner, with and without the use of an adhesive primer. MATERIALS AND METHODS: One-hundred and sixty-four acrylic resin specimens were fabricated and randomly distributed into four groups according to the type of surface treatment: Sofreliner Primer, NTP, Sofreliner Primer + NTP, and NTP + Sofreliner Primer. Two specimens interposed with relining material (Sofreliner) formed one test sample to perform the tensile bond strength tests, before (initial) and after storage (final) in saline solution (37°C, 90 days, n = 10). Surface characterization was performed by scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). The failure type was classified as cohesive, adhesive, or mixed. The data were analyzed statistically using the two-way ANOVA and Tukey test, as well as the chi-squared test (α = 0.05), Bonferroni correction (α = 0.005), and Spearman correlation coefficient (α = 0.05). RESULTS: The SEM and EDS analyses showed the presence of a thin, homogenous organic film in the groups treated with NTP. The NTP + Sofreliner Primer group presented the largest bond strength mean values in the initial period (p < 0.05). Sofreliner Primer and NTP + Sofreliner Primer groups presented the first and second largest tensile bond strength mean values in the final period (p < 0.05), respectively. NTP + Sofreliner Primer group also had the largest number of cohesive (70%, initial) and mixed (90%, final) failures. CONCLUSIONS: The NTP treatment performed before the primer application enhanced the bond between the acrylic resin ocular prosthesis and the Sofreliner silicone-based reliner, even after 90 days of immersion in saline solution.


Asunto(s)
Recubrimiento Dental Adhesivo , Siliconas , Resinas Acrílicas , Cementos Dentales , Análisis del Estrés Dental , Ojo Artificial , Ensayo de Materiales , Propiedades de Superficie , Resistencia a la Tracción
3.
BMC Oral Health ; 19(1): 75, 2019 05 03.
Artículo en Inglés | MEDLINE | ID: mdl-31053131

RESUMEN

BACKGROUND: The aim was to analyze the levels of stress of edentulous patients through the state-trait anxiety inventory (STAI) and salivary flow through the visual analogue scale (VAS) xerostomia questionnaire, as well as analyze the levels of cortisol, capillary blood glucose, and blood pressure (BP) before and after the installation of complete dentures. METHODS: Fifty patients were evaluated. The STAI and VAS xerostomia questionnaire were applied before the installation of the prosthesis, on the day of its installation, and 1 month after the last recall visit. The BP measurement, as well as salivary and blood collections, were performed before the installation of the prothesis, and 1 month after the last recall visit. Data from the VAS xerostomia questionnaire and cortisol levels were submitted to ANOVA and the Tukey test (P = .05). Data from the STAI, as well as blood glucose and BP levels, were submitted to the Chi-square test (P = .05). The correlation between cortisol and blood glucose and between cortisol levels and BP was analyzed. RESULTS: There was no statistically significant association between the questions of the VAS xerostomia questionnaire, STAI-state and STAI-trait scores, or the periods analyzed. However, the cortisol level collected in the morning decreased after the installation of the prosthesis. There was a correlation between cortisol and blood glucose and BP levels. CONCLUSIONS: The installation of complete dentures was beneficial for patients since it was probably responsible for the cortisol level reduction.


Asunto(s)
Ansiedad/metabolismo , Glucemia/metabolismo , Presión Sanguínea/fisiología , Dentadura Completa/psicología , Hidrocortisona/metabolismo , Estrés Psicológico/diagnóstico , Estrés Psicológico/psicología , Ansiedad/psicología , Humanos
4.
J Med Eng Technol ; 42(5): 359-367, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30251571

RESUMEN

In some clinical situations, the clinician may encounter previously installed implants that should be associated with other implants for a proper rehabilitation. The aim of this study was to evaluate the biomechanical behaviour of a multiple prosthesis joined by different implant connections using photoelasticity. Photoelastic models with a screwed fixed prosthesis supported by implants with different connection systems (Morse taper, external hexagon, internal hexagon, and Flexcone), and different combinations among them, were fabricated. Each assembly was placed in a circular polariscope, and axial and oblique (45°) loads of 100 N were applied on the occlusal surface of the crowns. The fringe patterns were photographed and the analysis was performed by counting the number of high-intensity fringes and also according to the stress distribution region where they appeared. Among implants of the same connection, the external connections obtained a greater number of high intensity fringes when compared to the internal connections. From the biomechanical point of view, the association between different types of connections obtained positive results.


Asunto(s)
Prótesis e Implantes , Fenómenos Biomecánicos , Estrés Mecánico
5.
J Med Eng Technol ; 41(4): 309-313, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28351185

RESUMEN

New systems are released in the odontological market with the objective of bringing improvements and advancements in the clinical success of implants and implant-supported prostheses. The distribution of tension for the bone/implant system of these new systems is important. The purpose of this work was to evaluate, by photoelastic analysis and strain gauges, the distribution of tension for the bone/implant system, using the Slim system. A photoelastic cast with an external hexagon implant was manufactured and a metal prosthesis was screwed below it, with or without the tested system. For the photoelasticity methodology, a photoelastic cast, with or without the tested system, was positioned in a circular polariscope, and axial loads of 100 N were applied to the centre of the crown. The pattern of tension generated was photographed and analysed qualitatively in an imaging programme. For the extensometry methodology, two extensometers were placed in the mesial and distal region of the implant in the photoelastic cast. The axial loads were applied to the group again, with or without the system (n = 10). The t test of independent samples with a significance level of 5% was used for this analysis. This study demonstrated greater tension values for both the photoelastic and extensometry methods when the tested system was used. Clinical studies must be performed to evaluate the tested system because the results might not be clinically significant to a bone reabsorption.


Asunto(s)
Implantes Dentales , Fenómenos Biomecánicos , Humanos , Ensayo de Materiales , Estrés Mecánico
6.
Implant Dent ; 26(1): 106-111, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28060024

RESUMEN

PURPOSE: The aim of this study was to assess stress distribution in the bone-implant interface of a mandibular implant-supported prosthesis with different cantilever lengths, aesthetic coating materials, and implant abutments. MATERIALS AND METHODS: A photoelastic model of an edentulous mandible, containing 5 external hexagon implants, was constructed. Experimental models were divided into 6 groups: group 1-UCLA component and metal bar; group 2-UCLA component and acrylic resin coating; group 3-UCLA component and porcelain coating; group 4-abutment and metal bar; group 5-abutment and acrylic resin coating; and group 6-abutment and porcelain coating. Forces were applied to the most anterior implant, the most posterior implant, and different cantilever lengths. RESULTS: The results showed a higher number of high-stress fringes as the cantilever length increased. Fringes were better distributed in groups with prostheses composed of acrylic resin and in groups that contained an abutment. CONCLUSION: The stress distribution in the bone-implant interface is improved when the cantilever is eliminated and when abutments in an acrylic resin prosthesis are used.


Asunto(s)
Prótesis Dental de Soporte Implantado/métodos , Dentadura Completa , Interfase Hueso-Implante/fisiopatología , Retención de Prótesis Dentales , Prótesis Dental de Soporte Implantado/normas , Análisis del Estrés Dental , Dentadura Completa/normas , Humanos , Técnicas In Vitro , Resinas Sintéticas/uso terapéutico , Soporte de Peso
7.
J Med Eng Technol ; 41(2): 115-121, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27696920

RESUMEN

Short dental implants have been used as an attempt to avoid bone grafts surgery, however there are few literature reports that evaluate changes to their design. Therefore, the aim of this study was to assess the effect of different short implant design on stress distribution through photoelastic analysis. Six external hexagon (5 × 5 mm) short dental implants with different design were used. Each group was treated with a single crown and a three element fixed partial dental prosthesis, resulting in a total of 12 photoelastic models. The assembling photoelastic model-implant-prosthesis was set in a circular polariscope where loads of 100N were applied on the occlusal surface with a Universal Test Machine (UTM). The tension fringes were photographed and later assessed qualitatively by a graphic software (Adobe Photoshop). Less high-intensity fringes were observed on the short implants with triangular threads, short external hexagon and flat apical profile. In conclusion, the macrodesign influenced the amount of stress distributed to the bone when short dental implants are placed.


Asunto(s)
Implantes Dentales , Dentadura Parcial Fija , Estrés Mecánico , Fenómenos Biomecánicos , Humanos , Ensayo de Materiales , Diseño de Prótesis
8.
J Prosthet Dent ; 117(5): 685-689, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-27881311

RESUMEN

STATEMENT OF PROBLEM: The rehabilitation of patients after a maxillectomy involves the use of an obturator to seal oral-nasal-sinus communication and to facilitate mastication, swallowing, and speech. PURPOSE: The purpose of this in vitro study was to evaluate different attachment systems used for implant-retained obturators at dissipation loads and under shear forces. MATERIAL AND METHODS: Photoelastic models were fabricated with 3 external hexagon implants at the incisor, canine, and first molar regions. Subsequently, overdentures were made, and metal hooks were placed at the incisor and first molar regions to displace the prostheses in the vertical, anterior, and posterior directions, with a constant speed of 50 mm/min. A photoelastic model with an O-ring or bar-clip system was placed in a circular polariscope, and tested with a universal testing machine. The images were recorded and high-intensity fringes were counted using software. For strain gauge analysis, each strain gauge was placed horizontally at the mesial and distal sides of the implants. The registered strains were submitted to 2-way ANOVA (α=.05). RESULTS: The O-ring showed the lowest number of high-intensity fringes in photoelastic imaging, while the strain gauge analysis showed the lowest stress values in the bar-clip group (P=.007). CONCLUSIONS: The stress around titanium implant necks was more damaging to surrounding bone, while the bar-clip attachment system had a better biomechanical performance. The bar-clip presented the lowest strain values around the dental implants and few high-intensity fringes.


Asunto(s)
Retención de Prótesis Dentales/métodos , Prótesis Dental de Soporte Implantado , Análisis del Estrés Dental/métodos , Prótesis de Recubrimiento , Obturadores Palatinos , Modelos Dentales , Diseño de Dentadura , Técnicas In Vitro , Ensayo de Materiales , Propiedades de Superficie , Titanio
9.
Toxicol In Vitro ; 36: 180-185, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27521695

RESUMEN

The aim of this study was to evaluate the influence of pigment incorporation on the cytotoxicity of ocular prosthesis N1 color acrylic resin. Nine samples were manufactured by heat-polymerization in water bath and divided into 3 groups: acrylic resin without pigment incorporation (group R), acrylic resin with pigment incorporation (group RP), and acrylic pigment (group P). Eluates formed after 72h of sample immersion in medium were incubated with conjunctival cell line (Chang conjunctival cells) for 72h. The negative control group consisted in medium without samples (group C). The cytotoxic effect from the eluates was evaluated using MTT assay (cell proliferation), ELISA assay (quantification of IL1ß, IL6, TNF α and CCL3/MIP1α) and RT-PCR assay (mRNA expression of COL IV, TGF ß and MMP9). Data were submitted to ANOVA with Bonferroni post-tests (p<0.05). All groups were considered non-cytotoxic based on cell proliferation. However, resin with pigment incorporation showed significant IL6 quantity increase. Resin without pigment incorporation exhibited higher mRNA expression of COL IV, MMP9 and TGF ß, however it was also observed for the negative control group. The materials exhibited divergent biological behavior. Despite the pigment incorporation that resulted in an increase of IL6, no cytotoxicity was observed based on cell proliferation.


Asunto(s)
Resinas Acrílicas/toxicidad , Colorantes/toxicidad , Conjuntiva/citología , Ojo Artificial , Línea Celular , Proliferación Celular/efectos de los fármacos , Colágeno Tipo IV/genética , Humanos , Metaloproteinasa 9 de la Matriz/genética , ARN Mensajero/metabolismo , Factor de Crecimiento Transformador beta/genética
10.
J Prosthet Dent ; 116(4): 501-506.e5, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27422232

RESUMEN

STATEMENT OF PROBLEM: Different factors can influence marginal bone loss around dental implants, including the type of internal and external connection between the implant and the abutment. The evidence needed to evaluate these factors is unclear. PURPOSE: The purpose of this systematic review was to evaluate marginal bone loss by radiographic analysis around dental implants with internal or external connections. MATERIAL AND METHODS: A systematic review was conducted following the criteria defined by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). Initially, a population, intervention, comparison, and outcome(s) (PICO) question was defined: does the connection type (internal or external) influence marginal bone loss in patients undergoing implantation? An electronic search of PubMed/MEDLINE and Scopus databases was performed for studies in English language published between January 2000 and December 2014 by 2 independent reviewers, who analyzed the marginal bone loss of dental implants with an internal and/or external connection. RESULTS: From an initial screening yield of 595 references and after considering inclusion and exclusion criteria, 17 articles were selected for this review. Among them, 10 studies compared groups of implants with internal and external connections; 1 study evaluated external connections; and 6 studies analyzed internal connections. A total of 2708 implants were placed in 864 patients. Regarding the connection type, 2347 implants had internal connections, and 361 implants had external connections. Most studies showed lower marginal bone loss values for internal connection implants than for external connection implants. CONCLUSIONS: Osseointegrated dental implants with internal connections exhibited lower marginal bone loss than implants with external connections. This finding is mainly the result of the platform switching concept, which is more frequently found in implants with internal connections.


Asunto(s)
Pérdida de Hueso Alveolar/etiología , Diseño de Implante Dental-Pilar/efectos adversos , Implantación Dental Endoósea/efectos adversos , Prótesis Dental de Soporte Implantado/efectos adversos , Humanos
11.
J Contemp Dent Pract ; 17(3): 211-6, 2016 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-27207200

RESUMEN

AIM: Epidermolysis bullosa (EB) represents a highly rare subgroup of skin diseases that affects skin and mucous membrane. The aim of the present study was to assess caries prevalence and its associated factors in EB subjects. Salivary status was also assessed. MATERIALS AND METHODS: Ten subjects with EB who were under supervision were selected (cases) and matched by age and gender with unaffected individuals (controls). Dental caries were recorded using the World Health Organization (WHO) criteria. Oral hygiene and dietary habits were investigated by clinical examination and questionnaires. Both nonstimulated and stimulated saliva were collected and salivary pH, buffering capacity and mouth opening were evaluated. RESULTS: The results showed that the median decay-missing-filled teeth was significantly higher (p = 0.0094) in EB cases 5 (3.9-20.3) than in controls 3 (2-3.25). The groups also differed when food consistency was analyzed. Individuals with EB have a higher intake of soft food. In addition, the median mouth-opening values from cases (0.84-2.84 cm) and controls (4.3-4.9 cm) have shown to be statistically different (p = 0.007). Considering the salivary parameters, none of them showed significant differences among groups. CONCLUSION: Epidermolysis bullosa subjects present higher caries scores and might be related to their physical condition and dietary habits. CLINICAL SIGNIFICANCE: There is a lack of information about oral status in EB subjects. Hence, our findings add useful information regarding the relationship between caries prevalence and associated risk factors in EB subjects.


Asunto(s)
Caries Dental/epidemiología , Epidermólisis Ampollosa/fisiopatología , Adolescente , Estudios de Casos y Controles , Niño , Epidermólisis Ampollosa/complicaciones , Conducta Alimentaria , Femenino , Alimentos , Humanos , Masculino , Higiene Bucal , Prevalencia
12.
J Med Eng Technol ; 40(2): 35-42, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26783652

RESUMEN

Photoelastic analysis was used to evaluate the biomechanical behaviour of implant-supported, double-screwed crowns with different connection systems and cantilever lengths. Three models were made in PL-2 photoelastic resin and divided into six groups, on the basis of the implant connection system (external hexagon [EH] or Morse taper [MT]), type of abutment (Mini Pilar [Neodent, Curitiba, Paraná, Brazil] or "UCLA") and number of crowns in the cantilever (one or two). The implant-prosthesis unit was placed in a circular polariscope. Occlusal surfaces of the crowns were subjected to 100-N loads in the axial and oblique (45°) directions in a universal testing machine (EMIC). Generated stresses were recorded and analysed qualitatively in a graphics program (Adobe Photoshop). Under axial loading, all of the groups had similar numbers of fringes, which were increased when the crowns were subjected to oblique loading. The highest number of fringes was found during oblique loading in the EH + Mini Pilar group. In conclusion, although the type of implant connection system did not have a direct influence on the stress distribution for axial loading, the cantilever length did have a direct influence on stress distribution. Models with two crowns in the cantilever showed more stress, with a greater concentration of force on the cervical part of the implant.


Asunto(s)
Implantes Dentales , Fenómenos Biomecánicos , Ensayo de Materiales , Fotograbar , Estrés Mecánico
13.
Am J Dent ; 28(3): 174-80, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26201230

RESUMEN

PURPOSE: To analyze whether immersion in sodium fluoride (NaF) solutions and/or common acidic beverages (test solutions) would affect the surface roughness or topography of lithium disilicate ceramic. METHODS: 220 ceramic discs were divided into four groups, each of which was subdivided into five subgroups (n = 11). Control group discs were immersed in one of four test beverages for 4 hours daily or in artificial saliva for 21 days. Discs in the experimental groups were continuously immersed in 0.05% NaF, 0.2% NaF, or 1.23% acidulated phosphate fluoride (APF) gel for 12, 73, and 48 hours, respectively, followed by immersion in one of the four test beverages or artificial saliva. Vickers microhardness, surface roughness, scanning electron microscopy (SEM) associated with energy dispersive spectroscopy, and atomic force microscopy (AFM) assessments were made. Data were analyzed by nested analysis of variance (ANOVA) and Tukey's test (α = 0.05). RESULTS: Immersion in the test solutions diminished the microhardness and increased the surface roughness of the discs. The test beverages promoted a significant reduction in the Vickers microhardness in the 0.05% and 0.2% NaF groups. The highest surface roughness results were observed in the 0.2% NaF and 1.23% APF groups, with similar findings by SEM and AFM. Acidic beverages affected the surface topography of lithium disilicate ceramic. Fluoride treatments may render the ceramic surface more susceptible to the chelating effect of acidic solutions.


Asunto(s)
Bebidas , Cariostáticos/química , Porcelana Dental/química , Fluoruros/química , Fluoruro de Fosfato Acidulado/química , Bebidas Gaseosas , Citrus sinensis , Café , Microanálisis por Sonda Electrónica , Frutas , Dureza , Humanos , Concentración de Iones de Hidrógeno , Ensayo de Materiales , Microscopía de Fuerza Atómica , Microscopía Electrónica de Rastreo , Saliva Artificial/química , Fluoruro de Sodio/química , Propiedades de Superficie , Factores de Tiempo , Vino
14.
J Med Eng Technol ; 39(6): 322-7, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26100976

RESUMEN

The aim of this study was evaluate the biomechanical behaviour of prostheses screwed into conventional (0° angulation) and pre-angled experimental (8, 12 and 20°) external hexagon implants (13 × 4 mm) by photoelastic analysis. Eight casts were made in photoelastic resin. Casts were divided into groups of single crowns or three combined elements. Each unit was positioned in a circular polariscope. By using a universal testing machine, 100 N loads were applied in the axial and oblique (45°) directions to fixed points on the occlusal surfaces of the crowns. Generated stresses were recorded photographically and analysed qualitatively in a graphics program. In single-element prostheses, the number of high-stress fringes increased with increasing implant angle. However, in three-element prostheses, there was no difference in the stress distribution with implant angle, except for the 12° implant that had a higher degree of stress. For the other groups pre-angulation of the implant increases the concentration and intensity of stresses for single prosthesis and has similar stress distribution in three-element fixed prostheses.


Asunto(s)
Implantes Dentales , Huesos/fisiología , Modelos Biológicos , Estrés Mecánico
15.
Ann Med Surg (Lond) ; 4(2): 200-3, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26052437

RESUMEN

INTRODUCTION: The treatment of orofacial tumors may cause facial deformities by losses of structures that affect basic functions, i.e. feeding, speech, and the reduction of patient self-steam. PRESENTATION OF CASE: A white male patient was diagnosed with epidermoid cancer on the mandibular alveolar ridge with infiltration staging IV A. The patient was submitted to a mandibulectomy associated with a complete extraction of mandibular teeth. For rehabilitation, a conventional denture for the mandibular arch and a removable partial denture for the maxillary arch were fabricated. A correct occlusal adjustment and a satisfactory amount of alveolar bone was favorable for conventional dentures of the prostheses bases improve their retention and stability. After one year of follow-up, the patient was adapted to the prostheses, satisfied with their retention, and reported an improvement on his feeding. DISCUSSION: The prosthetic rehabilitation of patients after a partial mandibulectomy is essential for their self-steam. Conventional dentures may have their retention and stability improved if they are well fabricated, recorded and have a balanced occlusion. CONCLUSION: A correct occlusal adjustment and an adequate retention of the prostheses bases may improve their retention and stability. Patients without xerostomy and with a satisfactory amount of alveolar bone may have a favorable prognosis for conventional dentures.

16.
Case Rep Dent ; 2015: 704348, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25705525

RESUMEN

The success of rehabilitation will not depend on just clinical procedures. A proper dental technique (ceramist) is required as well as the respect for some biomimetic principles to obtain the desired final result. This study has the purpose of describing a prosthetic rehabilitation with laminate veneers and all-ceramic crowns of a patient unsatisfied with a previous esthetic treatment because of the negligence of some biomimetic principles. A 45-year-old female patient was admitted to the dental clinic complaining about the lifelike appearance of her all-ceramic restorations. Before the fabrication of new restorations, a mock-up was conducted to verify the patient's satisfaction. A ceramist conducted all the fabrication process so that surface characterizations could be visually verified and the lifelike appearance of natural tooth could be reproduced. After the cementation procedure, the patient reported being satisfied with the lifelike appearance of the new restorations. Based on the clinical findings of the present case report, it can be concluded that the reproduction of the lifelike esthetic appearance of natural teeth and the visualization of the final results before definitive procedures are essential to obtain the clinical success.

17.
Int J Surg Case Rep ; 7C: 149-53, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25618842

RESUMEN

INTRODUCTION: The aim of this paper was to present a rehabilitation of a patient with a dynamic universal castable long abutment (UCLA) for a single tilted implant in the anterior maxillary area. PRESENTATION OF CASE: A 57-year-old male patient attended the dentistry college clinic complaining of a vertical fracture of a residual root of the dental element 22. The tooth extraction was indicated for the implant installation. Due to the socket buccal wall thickness, the implant was installed with an inclination to the palate. It was done in a two-stage surgical protocol, and an external hexagon implant (3.75×11.5mm) was placed. After a six-month healing period to correct the implant position, a dynamic UCLA was set in place, rectifying the implant emergence profile at 20°. The ceramic structure fitting was performed and, after the patient's consent, the prosthesis was finalized and installed. DISCUSSION: After a follow-up period of twenty months, no complications were observed. CONCLUSION: The installation of tilted implants with a dynamic UCLA may be a viable option, faster and less invasive than bone grafts.

18.
J Prosthet Dent ; 112(5): 1156-63, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24928773

RESUMEN

STATEMENT OF PROBLEM: Surface transformation with nonthermal plasma may be a suitable treatment for dental ceramics, because it does not affect the physical properties of the ceramic material. PURPOSE: The purpose of this study was to characterize the chemical composition of lithium disilicate ceramic and evaluate the surface of this material after nonthermal plasma treatment. MATERIAL AND METHODS: A total of 21 specimens of lithium disilicate (10 mm in diameter and 3 mm thick) were fabricated and randomly divided into 3 groups (n=7) according to surface treatment. The control group was not subjected to any treatment except surface polishing with abrasive paper. In the hydrofluoric acid group, the specimens were subjected to hydrofluoric acid gel before silane application. Specimens in the nonthermal plasma group were subjected to the nonthermal plasma treatment. The contact angle was measured to calculate surface energy. In addition, superficial roughness was measured and was examined with scanning electron microscopy, and the chemical composition was characterized with energy-dispersive spectroscopy analysis. The results were analyzed with ANOVA and the Tukey honestly significant difference test (α=.05). RESULTS: The water contact angle was decreased to 0 degrees after nonthermal plasma treatment. No significant difference in surface roughness was observed between the control and nonthermal plasma groups. Scanning electron microscopy and energy-dispersive spectroscopy images indicated higher amounts of oxygen (O) and silicon (Si) and a considerable reduction in carbon (C) in the specimens after nonthermal plasma treatment. CONCLUSIONS: Nonthermal plasma treatment can transform the characteristics of a ceramic surface without affecting its surface roughness. A reduction in C levels and an increase in O and Si levels were observed with the energy-dispersive spectroscopy analysis, indicating that the deposition of the thin silica film was efficient.


Asunto(s)
Cerámica/química , Porcelana Dental/química , Gases em Plasma/química , Grabado Ácido Dental/métodos , Argón/química , Carbono/análisis , Pulido Dental/instrumentación , Calor , Humanos , Ácido Fluorhídrico/química , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Oxígeno/análisis , Distribución Aleatoria , Silanos/química , Silicio/análisis , Dióxido de Silicio/química , Siloxanos/química , Espectrometría por Rayos X , Propiedades de Superficie , Tensión Superficial , Factores de Tiempo , Humectabilidad
19.
Case Rep Dent ; 2014: 270365, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24715992

RESUMEN

The gastroesophageal reflux disease (GERD) is one of the main causes of dental erosion. The aim of this case presented is to describe the prosthetic rehabilitation of a patient with GERD after 4 years of followup. A 33-year-old male patient complained about tooth sensitivity. The lingual surface of the maxillary anterior teeth and the cusps of the upper and lower posterior teeth presented wear. It was suspected that the feeling of heartburn reported by the patient associated with the intake of sports supplements (isotonics) was causing gastroesophageal changes. The patient was referred to a gastroenterologist and was diagnosed with GERD. Dental treatment was performed with metal-free crowns and porcelain veneers after medical treatment of the disease. With the change in eating habits, the treatment of GERD and lithium disilicate ceramics provided excellent cosmetic results after 4 years and the patient reported satisfaction with the treatment.

20.
J Contemp Dent Pract ; 14(3): 567-72, 2013 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-24172009

RESUMEN

AIM: The aim of this study is to evaluate through a literature review, the soft tissue response in contact with zirconia abutments, including case reports comparing prosthetics rehabilitations with zirconia and titanium abutments upto 3 years of follow-up as well as the factors that should be considered on implant's abutment selection. BACKGROUND: Metallic abutments can provide grayish color when in contact with thin soft tissues which may lead the implant prosthetic treatment to failure. In this context, the abutments of zirconia stand out because there is an excellent linking between esthetics and the health of peri-implant soft tissues. MATERIALS AND METHODS: A consult of the published researches was made on the PubMed database from 2000 to September 2012. The including criteria were: literature reviews, clinical studies and case reports in English that focused on the response of the soft tissue in contact with zirconia implant abutments. The studies that were not in English and did not match the tackled issue were excluded. RESULTS: A total of 32 articles were found. According to the search strategy, just 16 articles were selected for this review. Three studies affirmed that zirconia abutments have an excellent soft tissue response; one study showed increased gingival recession with zirconia abutments and nine studies do not stand out any difference on biological behavior between titanium and zirconia abutments. Three studies affirmed that zirconia abutments provide natural gingival appearance, anatomic contour and greater esthetics. CONCLUSION: The use of zirconia abutments is recommended for anterior regions because of their greater optical properties and esthetic results and more studies should be performed and analyzed longitudinally regarding their biological response. CLINICAL SIGNIFICANCE: The zirconia abutments have been established to be essential in order to achieve great esthetic results in cases of thin peri-implant soft tissues and in regions where the three-dimensional placement of implants is more superficial.


Asunto(s)
Diseño de Implante Dental-Pilar , Materiales Dentales/química , Odontología Basada en la Evidencia , Periodoncio/fisiología , Circonio/química , Estética Dental , Encía/fisiología , Humanos , Titanio/química
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