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1.
J Prosthet Dent ; 2021 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-33549342

RESUMEN

STATEMENT OF PROBLEM: Zirconia restorations create significant artifacts on 3D cone beam computed tomography (CBCT) imaging. Static computer-assisted implant surgery (s-CAIS) relies on the accuracy of superimposition between an intraoral surface scan and CBCT imaging. However, how the artifacts from zirconia on the tomographic image might affect the predictability of s-CAIS is unclear. PURPOSE: The purpose of this in vitro study was to evaluate the effect of zirconia crown restorations on the superimposition process for s-CAIS. MATERIAL AND METHODS: Four stone casts generated 4 groups: a control group (CG) with no crowns and 3 experimental groups with 4 (TG4), 7 (TG7), and 13 (TG13) zirconia crowns. A total of 40 CBCT scans were made for the 4 groups (n=10). All CBCTs were imported into a computer planning software program, and the casts from all 4 groups were scanned by using a high-resolution laboratory scanner. The standard tessellation language (STL) files were imported, segmented, and the 3 files superimposed for all groups. The accuracy of the superimposition was assessed, in millimeters, in 3 planes corresponding to anterior-posterior, horizontal, and vertical, as well as the overall measurement, and the results were analyzed statistically (α=.05). RESULTS: The overall analysis demonstrated statistically significant differences between all groups (P<.001), except between CG and TG4. The anterior-posterior dimension demonstrated significant differences between CG and TG7 (P<.001), CG and TG13 (P<.001), TG4 and TG7 (P=.004), and TG4 and TG13 (P=.001). For the vertical dimension analysis, significant differences were found between CG and TG7 (P=.001), CG and TG13 (P<.001), and TG4 and TG13 (P<.001). For the horizontal variable, statistically significant differences were found between CG and TG7 (P=.049), CG and TG13 (P<.001), TG4 and TG13 (P<.001), and TG7 and TG13 (P=.003). CONCLUSIONS: The accuracy of the superimposition of the images was influenced by the number of zirconia crowns, with an increased number reducing the superimposition accuracy.

2.
Compend Contin Educ Dent ; 41(9): e5-e9, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33001661

RESUMEN

This article describes the case of a partially edentulous patient who had undergone template-guided implant placement and was treated using a triple digital scanning protocol that allowed for CAD/CAM prosthodontic rehabilitation in a complete digital workflow. At the impression appointment, the provisional implant-supported screw-retained prosthesis was digitally scanned both intraorally (first scan) and, after removal, extraorally (second scan). After the second scan, scan bodies were placed intraorally and an implant-level digital impression was taken (third scan). The three standard tessellation language (STL) files derived from the three digital scans were imported in a CAD software and superimposed into one file that contained all of the information from the implant 3D position, prosthesis contours, and transmucosal part of the peri-implant soft tissues. The superimposition of the three STL files led to one master file to serve as a blueprint for the definitive prosthesis. The definitive monolithic zirconia prosthesis was CAM copy-milled, externally stained, and inserted. The patient was satisfied with both the esthetic and functional outcome and the minimally invasive, time-efficient, two-visit restorative protocol. In summary, this case report illustrates a technique for a complete digital workflow in an implant rehabilitation for the replacement of multiple missing teeth in the esthetic zone in two visits.


Asunto(s)
Implantes Dentales , Flujo de Trabajo , Diseño Asistido por Computadora , Prótesis Dental de Soporte Implantado , Estética Dental , Humanos
3.
J Prosthodont ; 29(6): 460-465, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32185825

RESUMEN

The purpose of the present report is to illustrate a proof-of-concept protocol with the double digital scanning (DDS) technique for complete digital workflow in double full-arch implant rehabilitation. Two patients (4 restored arches) presented with hopeless dentitions and they were treated with a 4-appointment prosthodontic protocol and monolithic zirconia prostheses implementing a complete digital workflow. The outcomes are presented after clinical and radiographic observation for 2 years.


Asunto(s)
Implantes Dentales , Prótesis Dental de Soporte Implantado , Diseño Asistido por Computadora , Diseño de Prótesis Dental , Humanos , Flujo de Trabajo , Circonio
4.
Clin Oral Implants Res ; 29(8): 835-842, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29926977

RESUMEN

OBJECTIVES: The aim of this in vitro study was to compare the accuracy of printed implant casts from digital impressions with two intra-oral scanners (IOS) to stone casts from conventional impressions. The hypothesis was that printed casts would be more accurate than stone casts from conventional impressions. MATERIALS AND METHODS: A mandibular stone cast with Kennedy class II edentulism was fabricated using two internal connection tissue-level implants at 30 degrees to each other (Replace Select RP, Nobel Biocare) to serve as master. Digital impressions (n = 10) were made with the white light (WL) and Active Wavefront Sampling technology (AWST) IOS. The resultant standard tessellation language (STL) datasets were used to print implant casts through stereolithography (SLA) prototyping. The conventional casts (n = 10) were produced with splinted open tray impression technique and polyether material in type IV stone. The master cast and all groups were digitized with lab reference scanner. The test groups STL datasets were superimposed to master cast STL in inspection software (Geomagic control 2015) to calculate root-mean-square error. RESULTS: The conventional, WL IOS and AWST IOS groups had mean values of 53.49 µm (SD 9.47), 108.09 µm (SD 9.59) and 120.39 µm (SD 5.91), respectively. The Shapiro-Wilk test showed no evidence of nonnormality (p = 0.131) and Levene's test showed no evidence of heterogeneity of variance (p = 0.518). The one-way ANOVA demonstrated a statistically significant difference (p < 0.001). Tukey's honest significant difference (HSD) showed statistically significant differences between all groups: for the comparison of AWST IOS and WL IOS, the p-value was 0.009, and the p-values of the other post hoc tests were <0.001. CONCLUSION: Printed casts generated from digital impressions for partially edentulous posterior mandibular arches had inferior accuracy to conventional stone casts fabricated from splinted open tray impressions. The printed casts from WL IOS had better accuracy compared to AWST IOS.


Asunto(s)
Diseño Asistido por Computadora , Técnica de Colado Dental , Técnica de Impresión Dental , Análisis de Varianza , Implantes Dentales , Materiales de Impresión Dental , Modelos Dentales , Humanos , Técnicas In Vitro , Arcada Parcialmente Edéntula , Mandíbula
5.
Compend Contin Educ Dent ; 39(4): e1-e4, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29600866

RESUMEN

Monolithic ceramics have been introduced in dentistry to help reduce technical complications reported with implant-supported metal-resin hybrid prostheses. This clinical report describes the maintenance and technical complications that occurred during a full-mouth implant rehabilitation using different prosthetic materials over a 7-year period. During the course of 4 of those years, multiple technical complications were encountered with the metal-resin hybrid prostheses, prompting the need for increased maintenance.New prostheses were inserted with screw-retained titanium frameworks and individually cemented single crowns, and subsequently no technical complications were encountered after 2 years of follow-up.


Asunto(s)
Coronas , Diseño de Prótesis Dental , Prótesis Dental de Soporte Implantado , Adulto , Materiales Dentales , Fracaso de la Restauración Dental , Humanos , Masculino , Cementos de Resina , Titanio
6.
J Prosthet Dent ; 119(4): 574-579, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28927923

RESUMEN

STATEMENT OF PROBLEM: To the authors' knowledge, while accuracy outcomes of the TRIOS scanner have been compared with conventional impressions, no available data are available regarding the accuracy of digital scans with the Omnicam and True Definition scanners versus conventional impressions for partially edentulous arches. PURPOSE: The purpose of this in vitro study was to compare the accuracy of digital implant scans using 2 different intraoral scanners (IOSs) with that of conventional impressions for partially edentulous arches. MATERIAL AND METHODS: Two partially edentulous mandibular casts with 2 implant analogs with a 30-degree angulation from 2 different implant systems (Replace Select RP; Nobel Biocare and Tissue level RN; Straumann) were used as controls. Sixty digital models were made from these 2 definitive casts in 6 different groups (n=10). Splinted implant-level impression procedures followed by digitization were used to produce the first 2 groups. The next 2 groups were produced by digital scanning with Omnicam. The last 2 groups were produced by digital scanning with the True Definition scanner. Accuracy was evaluated by superimposing the digital files of each test group onto the digital file of the controls with inspection software. RESULTS: The difference in 3-dimensional (3D) deviations (median ±interquartile range) among the 3 impression groups for Nobel Biocare was statistically significant among all groups (P<.001), except for the Omnicam (20 ±4 µm) and True Definition (15 ±6 µm) groups; the median ±interquartile range for the conventional group was 39 ±18 µm. The difference in 3D deviations among the 3 impression groups for Straumann was statistically significant among all groups (P=.003), except for the conventional impression (22 ±5 µm) and True Definition (17 ±5 µm) groups; the median ±interquartile range for the Omnicam group was 26 ±15 µm. The difference in 3D deviations between the 2 implant systems was significant for the Omnicam (P=.011) and conventional (P<.001) impression techniques but not for the True Definition technique (P=.247). CONCLUSIONS: Within the limitations of this study, both the impression technique and the implant system affected accuracy. The True Definition technique had the fewest 3D deviations compared with the other 2 techniques; however, the accuracy of all impression techniques was within clinically acceptable levels, and not all differences were statistically significant.


Asunto(s)
Arco Dental/anatomía & histología , Técnica de Impresión Dental , Modelos Dentales , Procesamiento de Imagen Asistido por Computador , Arcada Parcialmente Edéntula , Implantes Dentales , Humanos , Imagenología Tridimensional , Técnicas In Vitro
7.
J Esthet Restor Dent ; 30(1): 5-13, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-28792115

RESUMEN

OBJECTIVE: To illustrate a digital workflow in full-arch implant rehabilitation with minimally veneered monolithic zirconia and to report the outcomes including technical complications. CLINICAL CONSIDERATIONS: Three patients (5 edentulous arches) received full-arch fixed implant rehabilitation with monolithic zirconia and mild facial porcelain veneering involving a digital workflow. The incisal edges and occluding surface areas were milled out of monolithic zirconia to reduce the possibility of chipping. Porcelain veneering was applied on the facial aspect to improve the esthetic result. Outcomes and technical complications are reported after 2 years of clinical and radiographic follow-up. CONCLUSION: Implant and prosthesis survival rates were 100% after a short-term follow-up of 2 years. Technical complications were encountered in one patient. They did not adversely affect prosthesis survival or patient satisfaction and were easily addressed. A digital workflow for the design and fabrication of full-arch monolithic zirconia implant fixed implant prostheses has benefits, but caution is necessary during CAD planning of the prosthesis to ensure a successful outcome. Long-term clinical studies are needed to corroborate the findings discussed in this report. CLINICAL SIGNIFICANCE: This article presents an integrated digital workflow that was implemented for the implant-prosthodontic rehabilitation of three edentulous patients with monolithic zirconia prostheses. Monolithic zirconia has been successfully incorporated in implant prosthodontics in an effort to reduce the technical complications associated with bilayered ceramics. This workflow simplifies design and fabrication of the zirconia prostheses. However, caution should be taken during CAD planning of the prosthesis to make sure the zirconia cylinder is sufficiently thick at the interface with the titanium insert. Additionally, when cutback is planned for facial porcelain veneering, the functional occluding cusps and incisal edges should be fabricated in monolithic zirconia to avoid chipping.


Asunto(s)
Porcelana Dental , Prótesis Dental de Soporte Implantado , Diseño Asistido por Computadora , Diseño de Prótesis Dental , Fracaso de la Restauración Dental , Estudios de Seguimiento , Humanos , Flujo de Trabajo , Circonio
8.
Compend Contin Educ Dent ; 38(3): e9-e12, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28257219

RESUMEN

The surgical and prosthodontic management of patients with multiple missing teeth in the anterior maxilla can be challenging. The purpose of this clinical report is to illustrate the 2-year outcome after immediate implant placement in unintentional close proximity with the adjacent root. Following uneventful healing, the definitive implant rehabilitation was done with a modified monolithic zirconia framework and porcelain veneers bonded to the framework. The patient's satisfaction with the functional and esthetic outcomes remained high throughout the observation time, with no symptoms or biologic and technical complications.


Asunto(s)
Implantes Dentales , Prótesis Dental de Soporte Implantado , Carga Inmediata del Implante Dental , Incisivo , Fracturas de los Dientes/cirugía , Grabado Ácido Dental , Adulto , Porcelana Dental , Femenino , Humanos , Maxilar , Satisfacción del Paciente , Tratamiento del Conducto Radicular , Circonio
9.
J Esthet Restor Dent ; 29(3): 178-188, 2017 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-28316122

RESUMEN

OBJECTIVE: To present a rationale to reduce treatment complexity, number of surgeries, and overall treatment time for patients with extreme mandibular ridge deficiency. CLINICAL CONSIDERATIONS: A 67-year-old fully edentulous male presented with a chief complaint of poor retention and stability of the mandibular complete denture with consequent discomfort and inability to chew. A novel 3-appointment protocol from guided implant placement to definitive prosthesis delivery was implemented. At the first appointment, a guided surgery protocol with the All-on-4 concept was used in the mandible. Implant placement was followed by immediate loading with a fixed provisional prosthesis providing the patient with immediate function. Final impression, cast verification and articulation, determination of VDO, and interocclusal records were obtained in the same appointment. In the second appointment, the framework try-in was performed and a pick-up impression was taken after a new CR record. The third appointment included the delivery of the final screw-retained, one-piece, full-arch prosthesis opposed by a maxillary complete denture. CONCLUSION: This expedited protocol allows for implant placement with a surgical template generated from preoperative virtual planning of the implants and the CAD/CAM prosthodontic rehabilitation using a digital workflow. The patient was satisfied with the esthetic and functional outcome and was enrolled into a 6-month recall program. CLINICAL SIGNIFICANCE: This article describes an expedited protocol illustrating a digital workflow for full arch implant rehabilitation of the extremely atrophic mandible. Flapless implant placement with a surgical template generated from virtual planning was followed by immediate loading with a fixed prosthesis. Digital impression/digitization of the working cast and CAD/CAM technology were used to mill the definitive prosthesis. From guided surgery to the definitive rehabilitation only three appointments were necessary. This digital workflow can enhance patient acceptance and comfort and serve as an alternative treatment in the indicated clinical scenario. (J Esthet Restor Dent 29:178-188, 2017).


Asunto(s)
Prótesis Dental de Soporte Implantado , Dentadura Completa Inferior , Carga Inmediata del Implante Dental/métodos , Arcada Edéntula/rehabilitación , Anciano , Diseño de Dentadura , Humanos , Masculino , Mandíbula , Flujo de Trabajo
10.
Clin Oral Implants Res ; 28(11): 1360-1367, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28039903

RESUMEN

PURPOSE: To test whether or not digital full-arch implant impressions with two different intra-oral scanners (CEREC Omnicam and True Definition) have the same accuracy as conventional ones. The hypothesis was that the splinted open-tray impressions would be more accurate than digital full-arch impressions. MATERIAL AND METHODS: A stone master cast representing an edentulous mandible using five internal connection implant analogs (Straumann Bone Level RC, Basel, Switzerland) was fabricated. The three median implants were parallel to each other, the far left implant had 10°, and the far right had 15° distal angulation. A splinted open-tray technique was used for the conventional polyether impressions (n = 10) for Group 1. Digital impressions (n = 10) were taken with two intra-oral optical scanners (CEREC Omnicam and 3M True Definition) after connecting polymer scan bodies to the master cast for groups 2 and 3. Master cast and conventional impression test casts were digitized with a high-resolution reference scanner (Activity 880 scanner; Smart Optics, Bochum, Germany) to obtain digital files. Standard tessellation language (STL) datasets from the three test groups of digital and conventional impressions were superimposed with the STL dataset from the master cast to assess the 3D deviations. Deviations were recorded as root-mean-square error. To compare the master cast with conventional and digital impressions at the implant level, Welch's F-test was used together with Games-Howell post hoc test. RESULTS: Group I had a mean value of 167.93 µm (SD 50.37); Group II (Omnicam) had a mean value of 46.41 µm (SD 7.34); Group III (True Definition) had a mean value of 19.32 µm (SD 2.77). Welch's F-test was used together with the Games-Howell test for post hoc comparisons. Welch's F-test showed a significant difference between the groups (P < 0.001). The Games-Howell test showed statistically significant 3D deviations for all three groups (P < 0.001). CONCLUSION: Full-arch digital implant impressions using True Definition scanner and Omnicam were significantly more accurate than the conventional impressions with the splinted open-tray technique. Additionally, the digital impressions with the True Definition scanner had significantly less 3D deviations when compared with the Omnicam.


Asunto(s)
Arco Dental/anatomía & histología , Implantación Dental Endoósea/métodos , Implantes Dentales , Técnica de Impresión Dental , Diseño Asistido por Computadora , Técnica de Impresión Dental/instrumentación , Modelos Dentales , Humanos , Imagenología Tridimensional
11.
Compend Contin Educ Dent ; 38(1): e1-e4, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28054794

RESUMEN

As increased chipping rates have been reported with porcelain-fused-to-zirconia fixed dental prostheses, monolithic zirconia has been introduced in an effort to reduce the technical complications associated with bilayered ceramics. This clinical report illustrates the steps for achieving full-mouth implant rehabilitation with monolithic zirconia prostheses and minimal facial porcelain veneering. The benefits and limitations of this technique are also discussed. The incisal edges and occluding surface areas comprised monolithic zirconia to reduce the possibility of breakage and improve the esthetic outcome. Up to 1 year in function, no porcelain fracture was found.


Asunto(s)
Aleaciones Dentales , Diseño de Prótesis Dental , Circonio , Diseño Asistido por Computadora , Porcelana Dental , Coronas con Frente Estético , Estética Dental , Humanos , Masculino , Persona de Mediana Edad , Satisfacción del Paciente
12.
J Prosthet Dent ; 112(1): 70-8, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24674809

RESUMEN

STATEMENT OF PROBLEM: Different inlay casting waxes do not produce copings with satisfactory marginal accuracy when used on different die materials. PURPOSE: The purpose of this study was to evaluate the marginal accuracy of 4 inlay casting waxes on stone dies and titanium and zirconia abutments and to correlate the findings with the degree of wetting between the die specimens and the inlay casting waxes. MATERIAL AND METHODS: The inlay casting waxes tested were Starwax (Dentaurum), Unterziehwachs (Bredent), SU Esthetic wax (Schuler), and Sculpturing wax (Renfert). The marginal opening of the waxes was measured with a stereomicroscope on high-strength stone dies and on titanium and zirconia abutments. Photographic images were obtained, and the mean marginal opening for each specimen was calculated. A total of 1440 measurements were made. Wetting between die materials and waxes was determined after fabricating stone, titanium, and zirconia rectangular specimens. A calibrated pipette was used to place a drop of molten wax onto each specimen. The contact angle was calculated with software after an image of each specimen had been made with a digital camera. Collected data were subjected to a 2-way analysis of variance (α=.05). Any association between marginal accuracy and wetting of different materials was found by using the Pearson correlation. RESULTS: The wax factor had a statistically significant effect both on the marginal discrepancy (F=158.31, P<.001) and contact angle values (F=68.09, P<.001). A statistically significant effect of the die material factor both on the marginal adaptation (F=503.47, P<.001) and contact angle values (F=585.02, P<.001) was detected. A significant correlation between the marginal accuracy and the contact angle values (Pearson=0.881, P=.01) was also found. CONCLUSIONS: Stone dies provided wax copings with the best marginal integrity, followed by titanium and zirconia abutments. Unterziehwachs (Bredent), wax produced the best marginal adaptation on different die materials. A significant correlation was found between the marginal accuracy and the contact angle values. As the contact angle value became smaller, the marginal accuracy improved. All combinations of waxes and stone and titanium dies presented a high wettability.


Asunto(s)
Sulfato de Calcio/química , Pilares Dentales , Materiales Dentales/química , Colado de Cera para Incrustaciones/química , Titanio/química , Circonio/química , Adaptación Marginal Dental , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Ensayo de Materiales , Fotograbar/métodos , Polimetil Metacrilato/química , Propiedades de Superficie , Humectabilidad
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