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1.
Artículo en Inglés | MEDLINE | ID: mdl-33528462

RESUMEN

Conical retention with antirotational features (Acuris abutment) has been recently proposed for restorations of healed single implants. The conometric abutments use the retentive force of the coping-abutment system to retain the prosthetic crown without the use of cement or screws. This retentive force must be overcome to obtain detachment of the relined provisional crown in immediate restorations. The present article describes the use of digital scanning technology to virtually plan computer-guided implant placement and restoration with conical indexed abutments in postextraction sites. Importing the scan data of both matrix and patrix abutments that are seated on the definitive cast into the computer-aided design software provides a workflow to preoperatively mill a crown that perfectly fits the abutment into the postextraction site. This technique simplifies the provisional crown relining onto the conometric indexed abutment and reduces the intraoperative time.


Asunto(s)
Implantes Dentales , Prótesis Dental de Soporte Implantado , Diseño Asistido por Computadora , Coronas , Pilares Dentales , Diseño de Implante Dental-Pilar , Humanos , Tecnología
2.
Int J Prosthodont ; 34(1): 88-100, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33570524

RESUMEN

Emerging evidence implies significant interrelations between the condition of the peri-implant tissues and the implant-abutment-prosthesis complex. A new paradigm for studying the peri-implant tissues in close interrelation with the implant-abutment-prosthesis complex in the presence of the oral biofilm is essential. The aims of this paper are to introduce the concept of the "implant supracrestal complex" (ISC) and to describe the critical elements that define it as a unique anatomical and functional system of human tissues, mechanical components, and oral bacteria/biofilm. This paper reviews recent evidence to identify the impact of design features on short-term clinical outcomes and long-term health of the peri-implant bone and soft tissues. Prosthetic-driven implant placement is a prerequisite for proper ISC design, which in turn can indirectly influence the structure and dimensions of the peri-implant soft tissues. Design features of the implant-prosthesis-abutment complex, such as the emergence profile, emergence angle, and cervical margin, as well as the design of the implant-abutment and abutment-prosthesis junctions and their locations in relation to the tissues of the ISC, can have a significant impact on the maintenance of stable and healthy peri-implant tissues in the long term.


Asunto(s)
Pilares Dentales , Implantes Dentales , Diseño de Implante Dental-Pilar , Humanos
3.
Int J Oral Maxillofac Implants ; 36(1): 68-74, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33600525

RESUMEN

PURPOSE: The aim of this study was to test in vitro the bacterial microleakage at the Morse taper implant-abutment connection with switched platform subjected to functional load and thermocycling. MATERIALS AND METHODS: A total of 48 Morse taper implant-abutment connections with switched platforms (12 implants per group) were used. The abutments were attached to implants and presented in four groups: group 1, control; group 2, subjected to thermocycling; group 3, subjected to cyclic compressive loading; and group 4, subjected to thermocycling and cyclic compressive loading. All groups were then inoculated in Eppendorf tubes including three types of bacterial suspensions: Enterococcus faecalis, Staphylococcus aureus, and Pseudomonas aeruginosa for 7 and 14 days to detect possibility of bacterial infiltration from outside to the internal chamber of the implant. RESULTS: Implants not exposed to cyclic loading and thermocycling (group 1) and those exposed to thermocycling (group 2) exhibited no infiltration of E faecalis, S aureus, and P aeruginosa from outside to the inner chamber of the implant, while infiltration of P aeruginosa was only observed in implants subjected to cyclic loading only (group 3) and those subjected to cyclic loading in conjunction with thermocycling (group 4). CONCLUSION: Microbial leakage at the implant-abutment connection is influenced by the applied load alone and in combination with thermocycling; however, E faecalis and S aureus did not leak at the implant-abutment connection even under these circumstances. Only P aeruginosa infiltrated inside the implant-abutment connection, which might be caused by its swarming motility.


Asunto(s)
Implantes Dentales , Filtración Dental , Pilares Dentales , Diseño de Implante Dental-Pilar/efectos adversos , Implantes Dentales/efectos adversos , Filtración Dental/etiología , Enterococcus faecalis , Humanos , Ensayo de Materiales
4.
Int J Oral Maxillofac Implants ; 36(1): 177-181, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33600539

RESUMEN

PURPOSE: Abutment screw loosening is a frequently encountered prosthetic complication in implant dentistry. Due to the detection of preload loss soon after initial torque application, abutment screw retightening 10 minutes after initial tightening has been recommended. The aim of this clinical study was to assess preload maintenance in the abutment screws of single posterior implants after 1 month of use by employing screw-cement-retained prostheses and a clinical assessing method, with the ultimate goal of helping to improve the clinical workflow of implant-based restorations. MATERIALS AND METHODS: In total, 158 patients treated using three implant systems were divided randomly into two groups in which abutment screws were and were not retightened, respectively, approximately 10 minutes after initial torque application. Screw-cement-retained prostheses, which permitted the assessment of abutment screw preload maintenance and screw retightening after 1 month of use, were used. Preload loss at 1 month was defined as the failure to achieve the torque recommended for the abutment screws after 90-degree clockwise rotation of the screwdriver. The data were analyzed using binary logistic regression, with a significance level of P ≤ .05. RESULTS: No preload loss was detected 10 minutes after initial screw tightening. Preload loss was detected in 16 (10.13%) cases at 1 month after initial tightening, with no significant difference according to the implant system used, the presence or absence of retightening at 10 minutes after initial tightening, or implant position (premolar or molar). CONCLUSION: Under the experimental conditions of this study, abutment screws in some bone-level, internal tapered-connection, platform-switching implant systems showed preload loss at 1 month after abutment placement for single posterior implant-based restorations, regardless of implant system or whether abutment screws had been retightened 10 minutes after abutment placement, or implant position (premolar or molar). It is necessary to retorque the abutment screws 1 month after initial torque. The screw-cement-retained prostheses used in this study permit abutment screw retightening at that time and have advantages over traditional methods.


Asunto(s)
Pilares Dentales , Implantes Dentales , Tornillos Óseos , Diseño de Implante Dental-Pilar , Análisis del Estrés Dental , Humanos , Mantenimiento , Torque
5.
Int J Oral Maxillofac Implants ; 36(1): 47-54, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33600522

RESUMEN

PURPOSE: The aim of this in vitro study was to evaluate the mechanical behavior regarding dynamic fatigue of different implant-abutment connections and the unitary indication of abutments for all regions of the mouth. MATERIALS AND METHODS: This experimental study developed according to international standards (ISO 14801:2007) was performed using five types of implants and abutments: G1-external hex smart implant and 17-degree universal abutment (EHS); G2-cortical external hex implant and 17-degree universal abutment (EHTi); G3-internal hex implant and 30-degree universal abutment (IH); G4-Morse taper implant (11.5 degrees) and 17-degree universal abutment (MT11.5); and G5- Morse taper implant (16 degrees) and 30-degree universal abutment (MT16). A 15-Hz cyclic loading was applied to the specimens with the maximum number of cycles set at 5 × 106. Success was defined when three samples supported 5 million cycles without failure. The maximum load supported from each group after dynamic loading was recorded. The Spearman correlation and the Lowess method were used to analyze the correlation between the number of cycles and the applied load, and the Kruskal-Wallis and Nemenyi tests were used for comparison between the abutments when reaching 5 million cycles. RESULTS: There was a negative correlation (r < 0.00) and significant difference (P < .05) between the number of cycles and the load for each type of implant and abutment. The load values supported by each group after cyclic loading to achieve 5 million cycles were as follows: EHS, 225 N; EHTi, 215 N; IH, 220 N; MT11.5, 210 N; and MT16, 240 N. The MT16 implant-abutment assembly presented a significantly higher load (P = .024) than the MT11.5 implant-abutment assembly. CONCLUSION: All implant-abutment connections investigated in this study resisted average occlusal force values reported as acceptable in the literature and may be indicated for any region of the mouth.


Asunto(s)
Coronas , Diseño de Implante Dental-Pilar , Pilares Dentales , Diseño de Implante Dental-Pilar/efectos adversos , Análisis del Estrés Dental , Fatiga , Humanos , Ensayo de Materiales , Reproducibilidad de los Resultados
6.
J Prosthet Dent ; 125(4): 682.e1-682.e10, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33551133

RESUMEN

STATEMENT OF PROBLEM: Tissue-level internal connection implants are widely used, but the difference in abutment screw stability because of the shoulder coverage formed by the contact between the shoulder of the implant collar and the abutment remains unclear. PURPOSE: The purpose of this finite element analysis (FEA) and in vitro study was to investigate stress distribution and abutment screw stability as per the difference in shoulder coverage of the abutment in tissue-level internal connection implants. MATERIAL AND METHODS: Abutments were designed in 3 groups as per the shoulder coverage of the implant collar, yielding complete coverage (complete group), half coverage (half group), no coverage (no group) groups. In the FEA, a tightening torque of 30.0 Ncm was applied to the abutment screw, a force of 250 N was applied to the crown at a 30-degree angle, and the von Mises stresses and the stress distribution patterns were evaluated. In the in vitro study, the groups were tested (n=12). A total of 200 000 cyclic loads were applied at 250 N, 14 Hz, and at a 30-degree angle. Removal torque values and scanning electron microscopy (SEM) images were assessed. Removal torque values were analyzed by ANOVA and paired t tests. RESULTS: The maximum von Mises stress of the abutment screw was the lowest in the complete group, slightly higher in the half group, and highest in the no group. High stresses were concentrated in 1 location in the implant abutment connection area of the no group. The removal torque values after loading were significantly lower in the no group than in the complete group (P=.047). The SEM images revealed concentrated structural loss and wear in 1 location of the no group. CONCLUSIONS: FEA and in vitro studies confirmed that the shoulder coverage of the abutment in the tissue-level internal connection implant helped improve screw stability. Cyclic loading reduced the removal torque of the abutment screw.


Asunto(s)
Diseño de Implante Dental-Pilar , Implantes Dentales , Tornillos Óseos , Pilares Dentales , Análisis del Estrés Dental , Análisis de Elementos Finitos , Torque
7.
Artículo en Inglés | MEDLINE | ID: mdl-33348644

RESUMEN

Aim: (PRIMARY) Assess the changes in bone level (6 and 12 months after implant placement) between the test (definitive abutment (DEF)) and control (healing abutment (HEA)) groups. (SECONDARY) Assess the changes in bone level (6 and 12 months after implant placement) between the 1 mm high abutment group and 2 mm abutment group. Evaluate changes in implant stability recorded with analysis of the resonance frequency (RFA) Osstell system, at 6 and 12 months after implant placement, between the control group (HEA) and test (DEF). For the DEF group, the abutment was placed at the time of the surgery and was never removed. For the HEA group, the abutment was removed three times during the manufacture of the crowns. The abutments used were 1 mm high (Subgroup A) and 2 mm high (Subgroup B). Materials and methods: A total of 147 patients were selected between 54.82 ± 11.92 years old. After implant placement, patients were randomly distributed in the DEF and HEA group. After the implant placement, a periapical radiograph was taken to assess the peri-implant bone level; the same procedure was carried out 6 and 12 months post-placement. To compare the qualitative variables between the groups (HEA/DEF), the Chi-square test was used; for quantitative (MANOVA). Results: After a year, the accumulated bone loss was 0.48 ± 0.71 mm for the HEA group and 0.36 ± 0.79 mm for the DEF group, without statistical significance. Differences were only found due to timing (time) between 0 and 6 months (=0.001) and 0 and 12 months (0.001), with no differences attributable to the study groups (DEF and HEA). The accumulated bone loss (1 year) was 0.45 ± 0.78 mm for the 1 mm abutment group and 0.41 ± 0.70 mm for the 2 mm abutment group (p = 0.02). No differences were observed in implant stability between groups. Conclusions: The "One Abutment-One Time" concept does not reduce peri-implant bone loss compared to the connection-disconnection technique. The height of the abutment does influence bone loss: the higher the abutment, the lower the bone loss.


Asunto(s)
Pérdida de Hueso Alveolar/diagnóstico , Pilares Dentales , Implantes Dentales de Diente Único , Adulto , Anciano , Diseño de Implante Dental-Pilar , Implantación Dental Endoósea , Femenino , Humanos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias , Estudios Prospectivos , Resultado del Tratamiento
8.
Int J Oral Maxillofac Implants ; 35(5): 888-899, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32991638

RESUMEN

PURPOSE: The aim of this study was to evaluate the formed biofilm on two types of implant surfaces (hydrophilic or hydrophobic) associated with titanium (Ti) or zirconia (Zn) abutments. MATERIALS AND METHODS: Samples were separated into four groups according to type of surface and abutment used (n = 10): (1) hydrophobic/Ti abutment, (2) hydrophilic/Ti abutment, (3) hydrophobic/Zn abutment, and (4) hydrophilic/Zn abutment. Implant-abutment assemblies were incubated with human saliva and supragingival biofilm. Samples of biofilm were evaluated by DNA Checkerboard hybridization, identifying up to 41 species. Scanning electron microscopy (SEM) images were obtained from the implants and abutments. RESULTS: The microbial count was higher for samples from groups with the hydrophilic/Ti abutment, followed by hydrophobic/Zn abutment, hydrophilic/Ti abutment, and hydrophobic/Zn abutment (P < .05). Hydrophilic surfaces and Zn abutments showed the highest counts of microorganisms. Individual bacterial counts were variable between groups; the hydrophilic/Zn abutment group had the highest microbial diversity, including T forsythia, P nigrescens, S oralis, S sanguinis, L casei, M orale, P aeruginosa, P endodontalis, S aureus, S gallolyticus, S mutans, S parasanguinis, S pneumoniae, and C albicans. The hydrophilic/Ti abutment group had the highest count of T forsythia and T denticola, microorganisms of Socransky red complex. The SEM images showed the bacterial colonization in both surfaces of the implant and abutment. CONCLUSION: Different surfaces of implants and abutments showed significant differences in the count and diversity of species. The hydrophilic/Zn abutment group presented the highest count and diversity of target species.


Asunto(s)
Implantes Dentales , Titanio , Biopelículas , Diseño de Implante Dental-Pilar , Genómica , Humanos , Ensayo de Materiales , Circonio
9.
Int J Oral Implantol (Berl) ; 13(3): 279-290, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32879932

RESUMEN

PURPOSE: To investigate the influence of vertical mucosal thickness on marginal bone loss around implants with short and long prosthetic abutments and the marginal bone loss progression rate up to 18 months after prosthetic loading. MATERIALS AND METHODS: Internal hex platform-switched implants were placed equicrestally using a two-stage protocol in the posterior mandible of two groups of patients with different vertical mucosal thickness, thin (≤ 2.0 mm) and thick (> 2.0 mm). Elevated prosthetic abutments of different heights (1 mm or 3 mm) were randomly assigned for single screw-retained crowns in both groups. Mesial and distal marginal bone loss were measured at implant placement (T0) and crown delivery (after 4 months [T1]), and after 6 (T2), 12 (T3) and 18 months (T4) of functional loading. RESULTS: Eighty implants were placed in eighty patients. Three patients dropped out at T2. At T4, 74 out of 77 implants were functioning, resulting in a 96% survival rate. Marginal bone loss (mean ± SE) at T2 was significantly greater in the 1-mm abutment groups (0.61 ± 0.09 mm with thin mucosa; 0.64 ± 0.07 mm with thick mucosa) than in the 3-mm abutment groups (0.32 ± 0.07 mm with thin mucosa; 0.26 ± 0.04 mm with thick mucosa). The marginal bone loss pattern over 18 months of loading showed that the greatest amount of marginal bone loss occurred during the first 6 months of function. CONCLUSIONS: Internal hex platform-switched implants placed equicrestally and restored with 1-mm abutments presented greater marginal bone loss than identical implants with 3-mm abutments, with vertical mucosal thickness having no significant influence.


Asunto(s)
Diseño de Implante Dental-Pilar , Implantes Dentales , Coronas , Humanos , Mandíbula , Membrana Mucosa
10.
Med. oral patol. oral cir. bucal (Internet) ; 25(5): e691-e699, sept. 2020. tab, graf, ilus
Artículo en Inglés | IBECS | ID: ibc-196526

RESUMEN

BACKGROUND: To assess the effect of implantoplasty and implant-abutment design on the fracture resistance and macroscopic morphology of narrow-diameter (3.5 mm) dental implants. MATERIAL AND METHODS: SCREW-shaped titanium dental implants (n = 48) were studied in vitro. Three groups (n = 16) were established, based on implant-abutment connection type: external hexagon, internal hexagon and conical. Eight implants from each group were subjected to an implantoplasty procedure; the remaining 8 implants served as controls. Implant wall thickness was recorded. All samples were subjected to a static strength test. RESULTS: The mean wall thickness reductions varied between 106.46 and 153.75 μm. The mean fracture strengths for the control and test groups were, respectively, 1211.90 ± 89.95 N and 873.11 ± 92.37 N in the external hexagon implants; 918.41 ± 97.19 N and 661.29 ± 58.03 N in the internal hexagon implants; and 1058.67 ± 114.05 N and 747.32 ± 90.05 N in the conical connection implants. Implant wall thickness and fracture resistance (P < 0.001) showed a positive correlation. Fracture strength was influenced by both implantoplasty (P < 0.001) and connection type (P < 0.001). CONCLUSIONS: Implantoplasty in diameter-reduced implants decreases implant wall thickness and fracture resistance, and varies depending on the implant-abutment connection. Internal hexagon and conical connection implants seem to be more prone to fracture after implantoplasty


No disponible


Asunto(s)
Resistencia Flexional , Diseño de Implante Dental-Pilar , Implantación Dental/métodos , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Valores de Referencia , Análisis de Varianza , Factores de Tiempo , Propiedades de Superficie , Reproducibilidad de los Resultados
11.
Av. odontoestomatol ; 36(2): 89-97, mayo-ago. 2020. ilus, tab, graf
Artículo en Español | IBECS | ID: ibc-194690

RESUMEN

INTRODUCCIÓN: La conexión implante-pilar ha sido sugerida como crucial para el éxito a largo plazo de las restauraciónes sobre implantes oseointegración y para prevenir futuras complicaciónes biológicas y mecánicas. El objetivo de este estudio fué evaluar la influencia del test de fatiga cíclica en el comportamiento de las conexiones internas implante-pilar. MÉTODOS: 36 pilares mutiposición de implantes de titanio de conexión interna fueron divididos en 2 grupos: 18 pilares slim o curvos y 10 pilares rectos con diferentes alturas. Los pilares fueron apretados con una llave de torque a 30 Ncm. Una carga cíclica entre 175 N y 100 N fué aplicada con 30º de inclinación axial al sistema de implantes durante 5 millones de ciclos. RESULTADOS: Los tests biomecánicos muestran una fractura de los implantes y de los tornillos de retención a una carga límite de 100 N de los pilares slim curvos y de 130 N en los pilares rectos. La fracturas aparecieron en la zona de unión entre el cuello y el cuerpo del implante y en los tornillos protéscios. No se han encontrado fracturas en los pilares multiposición. CONCLUSIONES: Este estudio indican que los tests de fatiga cíclica son importantes para analizar la respuesta biomecánica de los diferentes pilares en las conexiones implante-pilar de los sistemas de implantes


INTRODUCTION: The connection implant-abutment has been suggested to be crucial for the long-term success of implant restorations and to prevent future biological and mechanic complications. The aim of this study was to evaluate the influence of fatigue cyclic test in the behavior of internal connection implant-abutments. METHODS: Thirty six titanium abutments of internal connection implants were divided in two groups: 18 slim and 18 right multiunit abutments with different length. Abutments were tightened to 30 Ncm with a torque controller. A cyclic load between 175 N and 100 N according to different implant abutments at a 30-degree angle to the long axis was applied to the implants for a 5 million cycles. RESULTS: Biomechanical testing showed implant and screw retention fracture in a limit load of 100 N of slim implant abutments and 130 N of right implant abutments. Fracture cracks were located in the area between neck and body of implants and screw retention. No abutment fractures were found. CONCLUSIONS: This study indicate that fatigue cyclic test are very important to analize the biomechanical behavior of different abutments in connection implant-abutment of implants systems


Asunto(s)
Implantes Dentales , Diseño de Implante Dental-Pilar , Instrumentos Dentales , Análisis del Estrés Dental/instrumentación , Análisis de Falla de Equipo/métodos , Titanio , Pilares Dentales , Estrés Mecánico
12.
Av. odontoestomatol ; 36(2): 99-106, mayo-ago. 2020. ilus
Artículo en Español | IBECS | ID: ibc-194691

RESUMEN

El uso de pilares de cicatrización transmucosos previos a la colocación del pilar protésico definitivo es una técnica que se ha desarrollado durante muchos años en la implantología clásica. La desconexión y conexión de forma repetida de estos pilares o aditamentos dan lugar a una respuesta ósea negativa que se manifiesta en forma de pérdida de hueso a nivel de la cresta marginal, acompañada por una migración apical de tejidos blandos. Este artículo pretende realizar una revisión de la literatura del estado actual del uso de los pilares transmucosos definitivos con colocación inmediata el día de la inserción de los implantes y el mantenimiento del sellado biológico, minimizando la pérdida ósea periimplantaria y remodelando de forma adecuada los tejidos blandos adyacentes, frente al protocolo tradiciónal del uso de aditamentos que se desconectan en multiples ocasiones produciendo pérdida ósea periimplantaria. La evidencia científica sugiere que los mejores resultados biológicos, estéticos y funciónales se consiguen con el uso del pilar definitivo colocado de forma inmediata a la inserción del implante, especialmente en implantes colocados de forma yuxtacrestal y en implantes postextracción


The use of transmucosal healing abutments before the placement of the definitive prosthetic abutment is a technique that has been developed for many years in classical implantology. Repeated disconnection and connection of theses abutments result in a negative bone response that manifests as bone loss at the marginal ridge level, accompanied by apical soft tissue migration. This article aims to review the current status in the scientific literature of the use of the definitive transepithelial abutments with immediate placement on the day of implant insertion and maintenance of the biological seal, minimizing peri-implant bone loss and adequately remodeling the adjacent soft tissues, compared to the traditional protocol of the use of abutments that are disconnected on multiple occasions producing peri-implant bone loss. Scientific evidence suggests that the best biological, aesthetic, and functional results are achieved with the use of the definitive abutment placed immediately after implant insertion, especially in yuxtacrestal implants and post-extraction implants


Asunto(s)
Humanos , Diseño de Implante Dental-Pilar/métodos , Carga Inmediata del Implante Dental/métodos , Implantes Dentales , Pilares Dentales , Mucosa Bucal , Tejido Periapical/diagnóstico por imagen , Tejido Periapical/cirugía
13.
Av. odontoestomatol ; 36(2): 107-115, mayo-ago. 2020. ilus
Artículo en Español | IBECS | ID: ibc-194692

RESUMEN

La evolución en los diseños de los sistemas de implantes y en la configuración de los pilares protésicos ha desarrollado el concepto de plataforma reducida que comprende la colocación de un pilar más estrecho que la plataforma del implante para aumentar su distancia de la interfase hueso-implante. La plataforma reducida es considerada un factor importante para preservar la estabilidad del hueso crestal y de los tejidos blandos y asegurar el éxito de los implantes dentales a largo plazo. La plataforma reducida reduce las fuerzas oclusales y la contaminación bacteriana en la interfase entre el hueso crestal y el implante. Los estudios experimentales en animales y clínicos en pacientes muestran su eficacia para prevenir la pérdida ósea y de los tejidos blandos periimplantarios


The evolution of designs of implant systems and abutments configurations has developed the concept of platform-switching that involves the connection of a narrower abutment to the platform implant to allow horizontal distance of the interface bone-implant. Platform-switching is considered an important factor to preserve the stability of crestal bone and soft tissue ensuring the success of dental implants in the long-term follow-up. Platform-switching reduces the forces of occlusal loading and bacterial contamination in the interface between the crestal bone and the implant. Experimental studies in animals and clinical studies in patients showed that implants with platform-switching have demonstrated the effectiveness to prevent peri-implant bone loss and subsequent soft tissue los


Asunto(s)
Animales , Perros , Implantes Dentales/veterinaria , Implantación Dental Endoósea/métodos , Implantación Dental Endoósea/veterinaria , Diseño de Implante Dental-Pilar/métodos , Diseño de Implante Dental-Pilar/veterinaria , Oseointegración
14.
Med. oral patol. oral cir. bucal (Internet) ; 25(4): e449-e454, jul. 2020. ilus, tab
Artículo en Inglés | IBECS | ID: ibc-196495

RESUMEN

BACKGROUND: The aim of the authors was to examine the abutment-fixture interface in Morse-type conical implants in order to verify gaps at this level using a new microscopical approach. MATERIAL AND METHODS: In this in vitro study, 20 abutment-fixture complexes were prepared by sectioning (longitudinal and cross-sectional to the long axis) with a microtome and then with a focused ion beam (FIB). This is a micrometric machine tool that uses gallium ions to abrade circumscribed areas to dig deeper into the cuts obtained with the microtome in order to eliminate cut-induced artifacts. This is because the FIB abrasion is practically free from artifacts, which are normally generated by the action of the microtome blades or other techniques. Samples were then observed by scanning electron microscopy (SEM). RESULTS: The observation of the abraded parts with the FIB permitted measurement of the real gap between the implant-abutment components. A variable amount of gap was retrieved (from 0 to 3 μm) by the observations, confirming the non-hermetic nature of the connection. It has to be pointed out that in approximately 65% of cases, the gap accounted for less than 1 μm. CONCLUSIONS: The reported data confirmed that the analyzed connection system allowed for minimal gap. However, from the evidence of the present analysis, it cannot be assumed that the 2 parts of a Morse-type conical implant are fused in 1 piece, which would create a perfectly matched hermetic connection


No disponible


Asunto(s)
Diseño de Implante Dental-Pilar/métodos , Implantación Dental Endoósea/métodos , Propiedades de Superficie , Valores de Referencia , Microscopía Electrónica de Rastreo , Reproducibilidad de los Resultados
15.
J Oral Sci ; 62(3): 331-334, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32581180

RESUMEN

Zirconia is widely employed as a material during dental implant work because of its superior esthetics. This study sought to evaluate the impact of titanium or zirconia implant abutments on epithelial attachments after ultrasonic cleaning. These implants were inserted into the extraction socket of rat maxillary first molars. Then, the length of the horseradish peroxidase (HRP) reaction was measured. In addition, titanium and zirconia disks were cleaned using an ultrasonic scaler, surface morphology changes were observed, and the number of epithelial cell attachments to the surface was measured. Ultimately, the surfaces of the titanium disks were easier to damage than those of the zirconia ones. There was no difference in the number of epithelial cell attachments between the two materials with the ultrasonic cleaning. The length of the HRP reaction was shorter on the zirconia implant abutment surface than on the titanium one after mechanical cleaning. In conclusion, zirconia is harder than titanium and a better choice for use in the epithelial tissue attachment. Zirconia is more suitable as a material for implant abutments than titanium.


Asunto(s)
Implantes Dentales , Titanio , Animales , Pilares Dentales , Diseño de Implante Dental-Pilar , Materiales Dentales , Inserción Epitelial , Ensayo de Materiales , Ratas , Ultrasonido , Circonio
16.
Med Oral Patol Oral Cir Bucal ; 25(4): e449-e454, 2020 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-32520924

RESUMEN

BACKGROUND: The aim of the authors was to examine the abutment-fixture interface in Morse-type conical implants in order to verify gaps at this level using a new microscopical approach. MATERIAL AND METHODS: In this in vitro study, 20 abutment-fixture complexes were prepared by sectioning (longitudinal and cross-sectional to the long axis) with a microtome and then with a focused ion beam (FIB). This is a micrometric machine tool that uses gallium ions to abrade circumscribed areas to dig deeper into the cuts obtained with the microtome in order to eliminate cut-induced artifacts. This is because the FIB abrasion is practically free from artifacts, which are normally generated by the action of the microtome blades or other techniques. Samples were then observed by scanning electron microscopy (SEM). RESULTS: The observation of the abraded parts with the FIB permitted measurement of the real gap between the implant-abutment components. A variable amount of gap was retrieved (from 0 to 3 µm) by the observations, confirming the non-hermetic nature of the connection. It has to be pointed out that in approximately 65% of cases, the gap accounted for less than 1 µm. CONCLUSIONS: The reported data confirmed that the analyzed connection system allowed for minimal gap. However, from the evidence of the present analysis, it cannot be assumed that the 2 parts of a Morse-type conical implant are fused in 1 piece, which would create a perfectly matched hermetic connection.


Asunto(s)
Diseño de Implante Dental-Pilar , Implantes Dentales , Estudios Transversales , Pilares Dentales , Análisis del Estrés Dental , Ensayo de Materiales
17.
Braz Dent J ; 31(2): 127-134, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32556011

RESUMEN

The aim of this study was to assess the internal and vertical marginal fit of metallic copings to abutments and the fracture strength of different narrow diameter dental implant/abutments, either submitted to thermomechanical cycling or not. Sixty-four implant/abutments (n=16) were divided into 4 groups according to diameter and abutment type: G3.5-UAC (morse taper implant Ø3.5mm + universal abutment with beveled chamfer finish); G2.9-UAS (morse taper implant Ø2.9mm + universal abutment with shoulder finish); G2.8-AA (morse taper friction implant Ø2.8mm + anatomical abutment) and G2.5-HP (one-piece implant Ø2.5mm with indexed hexagonal platform). Each group was divided into two subgroups (n=8): submitted and not submitted to thermomechanical cycling (TMC). To assess internal and vertical marginal fit of metallic copings, the assemblies were scanned using microtomography (micro-CT) (n=5). The samples were subjected to the compressive strength test on a universal test machine. Group G3.5-UAC showed the highest marginal misfit regardless of TMC (p<0.05). All other groups were similar after TMC. Group G2.8-AA showed the lowest internal misfit both with and without TMC (p<0.05). Group G2.8-AA showed the highest fracture strength, similar only to G2.5-HP without TMC and G3.5-UAC with TMC. The type of abutment affects the internal and marginal fit of metallic copings and the anatomical abutment led to the best internal and marginal coping fit. The narrow diameter dental implant/abutments differ in terms of fracture strength, the strongest assembly was that composed by implant of type V grade titanium without internal threads (friction implant).


Asunto(s)
Implantes Dentales , Pilares Dentales , Diseño de Implante Dental-Pilar , Análisis del Estrés Dental , Resistencia Flexional , Ensayo de Materiales , Titanio , Circonio
18.
Int J Oral Maxillofac Implants ; 35(3): 479-484, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32406643

RESUMEN

PURPOSE: This in vitro study evaluated the effectiveness of a sealing agent on vertical misfit of the implant-abutment interface in an external hexagon implant system before and after mechanical cyclic loading. Effects on preload maintenance of retaining screws after mechanical cycling were also assessed. MATERIALS AND METHODS: External hexagon implant systems were divided into two groups (n = 12) according to the presence of an anaerobic sealing gel (control group-no sealing gel; experimental group-sealing gel applied). A prefabricated UCLA abutment was attached to the external hexagon implant with a digital torque wrench in accordance with the recommendations of the manufacturer. Specimens were tested through mechanical cyclic loading (1 × 106 cycles, 2 Hz, and 130 N). Vertical misfit of the implant-abutment interface was analyzed using a stereomicroscope, and reverse torque values were obtained using a digital wrench. Misfit and reverse torque data were measured and analyzed via analysis of variance (ANOVA) and the Tukey least significant difference test (α = .05). RESULTS: The sealing gel promoted lower vertical misfit values in the test group after mechanical cycling compared with before cycling (P = .009). The control group showed lower reverse torque values for retaining screws compared with the initial torque after mechanical cyclic loading (P < .0001). However, sealing gel application promoted higher reverse torque values in the test group postcycling (P = .0003). CONCLUSION: Anaerobic sealing agent application improved vertical misfit of the implant-abutment interface and preload maintenance of screw-retained implant-supported prostheses post-mechanical cycling.


Asunto(s)
Pilares Dentales , Implantes Dentales , Diseño de Implante Dental-Pilar , Prótesis Dental de Soporte Implantado , Análisis del Estrés Dental , Torque
19.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 55(5): 337-342, 2020 May 09.
Artículo en Chino | MEDLINE | ID: mdl-32392977

RESUMEN

Objective: To study the bacterial microleakage at the interface between dental implant and abutment in rats. Methods: Under aseptic conditions, suspension of 0.25 µl of Porphyromonas gingivalis (Pg) (10(9) CFU/ml) was added into the customized implant. After the abutment was connected, the suspension was cultured in an Ep (eppendorf) tube containing 1 ml brain heart infusion (BHI) culture medium. After 7 days and 14 days, the liquid in the Ep tube was taken and inoculated, and the growth of bacteria was observed. Six male SD rats with 12 implants were divided into experimental group (4 implants), negative control group (4 implants) and blank control group (4 implants). All 6 rats had two implants implanted in their bilateral upper jaws. During the second operation, suspension of 0.25 µl Pg (10(9) CFU/ml) was added to the inner part of the implant of the experimental group, culture solution of 0.25 µl was added to the control group and nothing was added to the blank control group. The amount of Pg and total bacteria in each group were evaluated by quantitative real-time PCR (qPCR). The inflammatory cell infiltrate in the peri-implant mucosa was evaluated histomorphometrically. Results: The in vitro model directly verified the presence of bacterial microleakage at implant-abutment interface (IAI), and the animal model confirmed the existence of microleakage through the infiltrate of inflammatory cells near the micro-gap in the experimental group indirectly. In vitro experiments found that Pg had penetrated from the implant within a week by observation and culture. In animal study, the presence of 10(2)-10(4) Pg was detected in the experimental group and it was not detected in the negative control group and the blank control group. At the same time, under the light microscope, in the experimental group, there were inflammatory cells aggregation in the connective tissue around the micro-gap and the density of inflammatory cells gradually decreased from the micro-gap to coronal and the apical of the connective tissue, while there were only scattered inflammatory cells in the connective tissue around the blank control group and the negative control group. In the experimental group, inflammatory cells density in area of 0.25-0.50 mm, 0-0.25 mm coronal to the micro-gap and 0-0.25 mm, 0.25-0.50 mm apical to the mico-gap was respectively, 976 (655), 1 673 (1 245), 2 267 (819) and 895 (162) cells/mm(2),which was significantly more than the blank control group in the corresponding position [respectively 201 (180), 321 (351), 309 (236) and 218 (272) cells/mm(2)] (P<0.05). Conclusions: Pg in the dental implants of rats can be found in the microleakage through implant-abutment interface, and cause the soft tissue inflammation around the implant, and the inflammation has certain distribution characteristics.


Asunto(s)
Pilares Dentales , Implantes Dentales , Filtración Dental/microbiología , Modelos Animales de Enfermedad , Animales , Diseño de Implante Dental-Pilar , Masculino , Ensayo de Materiales , Porphyromonas gingivalis , Ratas , Ratas Sprague-Dawley , Propiedades de Superficie
20.
Int J Periodontics Restorative Dent ; 40(3): e119-e126, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32233192

RESUMEN

This study evaluates the microbial colonization in the peri-implant sulci and in implant-abutment interfaces of Laser-Lok implants (BioHorizons) with laser-microgrooved abutments (test group) and machined abutments (control group) 18 months after functional loading Real-time polymerase chain reaction revealed significantly greater total and specific microbial load in both the peri-implant sulcus and implant-abutment interface in the control group (P ≤ .05) Similarly, there was a significant reduction in the radiographic crestal bone loss in the test group (P ≤ .05) In total, 14 patients were assessed for clinical and radiographic parameters and microbial evaluation Peptostreptococcus micros and Porphyromonas gingivalis were positively correlated with site-specific plaque scores and bleeding scores, and mean crestal bone loss, respectively Hence, the authors propose using Laser-Lok implants with laser-microgrooved abutments to reduce microbial colonization and consequently preserve the crestal bone levels.


Asunto(s)
Pérdida de Hueso Alveolar , Implantes Dentales , Pilares Dentales , Diseño de Implante Dental-Pilar , Implantación Dental Endoósea , Humanos , Índice Periodontal
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