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1.
Braz. j. oral sci ; 21: e224977, jan.-dez. 2022. ilus
Artigo em Inglês | LILACS, BBO - Odontologia | ID: biblio-1354723

RESUMO

Aim: This study aims to evaluate the clinical assessment results of periimplant soft tissue with morse taper (internal abutment connection). Methods: The study was conducted using a rapid review by searching the articles from PubMed NCBI and Cochrane by using keywords. All articles were selected by the year, duplication, title, abstract, full-text, and finally, all selected articles were processed for final review. Following clinical parameters were included; Periimplant Probing Pocket Depth (PPD), Plaque Score (PS), modified Plaque Index (mPI), Mucosal Thickness (MTh), Gingival Height (GH), periimplant mucosal zenith, Pink Esthetic Score (PES), Bleeding On Probing (BOP), Sulcus Bleeding Index (SBI), and modified Gingival Index (mGI). Results: 9 selected articles were obtained from the initial literature searching count of 70 articles. The overall samples included 326 morse taper implants. Based on the evaluation, 3 out of 4 articles reported pocket depth < 4 mm, no bleeding was reported in 2 out of 4 articles. 4 out of 4 articles reported low plaque accumulation, low soft tissue recession was reported in 3 out of 3 articles, and 4 out of 4 articles reported acceptable PES values. Conclusion: The evaluations indicate that the morse taper (internal abutment connection) has favorable assessment results based on various clinical parameters


Assuntos
Implantes Dentários , Dente Suporte , Lesões dos Tecidos Moles , Projeto do Implante Dentário-Pivô , Gengiva , Mucosa Bucal
2.
Int J Oral Maxillofac Implants ; 37(2): 339-345, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35476863

RESUMO

PURPOSE: To evaluate the use of a new resin metal opaquer on the surface of titanium abutments, in combination with two luting agents, and its effect on the retentive strength of implant-supported zirconia copings. MATERIALS AND METHODS: Sixty customized titanium abutments were designed and fabricated with virtual design software and a milling machine. Thirty abutment specimens were coated with metal opaquers, and the others were not coated. Then, the titanium abutments were fitted into the implant analogs, and the abutment-implant analog complexes were embedded in acrylic resin blocks. Sixty CAD/CAM-fabricated zirconia copings were seated on the abutments and secured with glassionomer cement or self-adhesive resin cement. The specimens were stored in 100% humidity for 1 hour and artificial saliva for 23 hours at 37°C before thermocycling for 5,000 cycles of 5°C to 55°C with a 30-second dwell time. The retentive strength was measured using a pull-out test with a universal testing machine. The dislodgment forces were statistically analyzed via two-way analysis of variance (ANOVA). The failure modes were evaluated and categorized by examining the fracture surface. RESULTS: The metal opaquer material had a significant negative effect on retention of zirconia copings. The nonopaquer titanium abutments showed significantly (P < .05) higher retentive strength than the metal opaquer abutments. Comparing the cements, the retentive strength values of self-adhesive resin cement were significantly higher than those of glass-ionomer cement. The metal opaquer groups exhibited mostly mixed-type failures, a combination of adhesive failures and cohesive failures, whereas the nonopaquer groups showed mostly adhesive-type failures. CONCLUSION: The titanium abutments coated with the new metal opaquer material resulted in a reduction of retentive strength. Self-adhesive resin cements exhibited significantly higher retention than glass-ionomer cements.


Assuntos
Implantes Dentários , Cimentos de Resina , Adaptação Psicológica , Dente Suporte , Cimentos Dentários , Retenção em Prótese Dentária/métodos , Análise do Estresse Dentário , Cimentos de Ionômeros de Vidro , Teste de Materiais , Propriedades de Superfície , Titânio , Zircônio
3.
BMC Oral Health ; 22(1): 108, 2022 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-35366875

RESUMO

BACKGROUND: This in vitro study aimed to provide evidence regarding the selection of hole diameters of implant crowns to reduce excess cement extrusion at the abutment margin, and to examine the maintenance of their retention capacity in anterior and posterior cement-retained implant crowns. METHODS: Six groups of implant crowns were prepared according to the position of the teeth and the size of their holes as follows: anterior crown without hole (ANH), anterior crown with 1-mm mini venting hole (AMH), anterior crown with 2.5-mm regular screw access hole (ARH), posterior crown without hole (PNH), posterior crown with 1-mm mini venting hole (PMH), and posterior crown with 2.5-mm regular screw access hole (PRH). Temporary cement was used to bond the crowns to the abutments. The mean amount of excess cement extrusion among the different groups at the abutment margin was calculated. Retentive strength under different hole designs was measured as the dislocation force of the crown using a universal testing machine. One-way ANOVA and Welch's t-test were used to analyze the results. RESULTS: The average amounts of extruded excess cement were 18.96 ± 0.64, 1.78 ± 0.41, and 1.30 ± 0.41 mg in the ANH, AMH, and ARH groups, respectively, and 14.87 ± 0.36, 1.51 ± 0.40, and 0.82 ± 0.22 mg in the PNH, PMH, and PRH groups, respectively. The hole opening in the crowns could significantly reduce residual cement regardless of its size (p < 0.001). The mean retentive strengths were 54.16 ± 6.00, 47.63 ± 13.54, and 31.99 ± 7.75 N in the ANH, AMH, and ARH groups, respectively, and 57.84 ± 10.19, 53.22 ± 6.98, and 39.48 ± 5.12 N in the PNH, PMH, and PRH groups, respectively. The retention capacity of the implant crown deteriorated rapidly as the holes on the crown surface enlarged. CONCLUSIONS: The presence of a hole on the implant crown reduced the amount of excess cement. The retention ability of the implant crowns deteriorated as the size of the hole increased. Considering the esthetic effect of the crown and the possible influence on crown retention, an implant crown with a 1-mm mini venting hole is a better clinical choice than the one with a 2.5-mm regular screw access hole.


Assuntos
Dente Suporte , Implantes Dentários , Parafusos Ósseos , Cimentação/métodos , Coroas , Prótese Dentária Fixada por Implante/efeitos adversos , Humanos
4.
Artigo em Inglês | MEDLINE | ID: mdl-35472113

RESUMO

This study evaluated the pull-off force between titanium abutments and zirconia crowns that were bonded using four different cements and two abutment heights (AHs). In total, 24 titanium abutments (3-mm AH: n = 12; 5-mm AH: n = 12; taper: 7.5 degrees) and 24 zirconia crowns were designed, manufactured, cemented with one of four dental cements (one temporary, two semi-permanent, one permanent), stored in water for 24 hours, and thermocycled (37,500 cycles, equal to ~4 years in vivo). The pull-off force needed to separate the abutment and crown in each combination was determined eight times per combination of cement type and abutment height. Statistical analysis was conducted at a significance level of P < .05. The permanent self-adhesive composite cement showed a high pull-off force with a risk for crown fracture (mean: 381 N for 3-mm AH; 617 N for 5-mm AH). In contrast, the temporary zinc-oxide cement showed frequent premature decementation after thermocycling (mean: 14 N with 3-mm AH; 28 N with 5-mm AH). Both semi-permanent methacrylate-based cements ranked between the other cements (mean: 31 N/37 N for 3-mm AH; 120 N/72 N for 5-mm AH). Statistically significant differences were found between all cements (ANOVA P < .001). The abutment heights differed significantly for all cements (P < .005) except for the temporary zinc-oxide cement. Methacrylate-based cements were the most reliable cements for semi-permanent mounting of zirconia crowns on titanium abutments. They provide sufficient retention to avoid unintended loosening and are weak enough to remove the crown without causing damage.


Assuntos
Implantes Dentários , Titânio , Coroas , Dente Suporte , Cimentos Dentários , Materiais Dentários , Prótese Dentária Fixada por Implante , Análise do Estresse Dentário , Cimentos de Ionômeros de Vidro , Humanos , Teste de Materiais , Metacrilatos , Óxidos , Zinco , Zircônio
5.
Int J Comput Dent ; 25(1): 83-98, 2022 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-35322655

RESUMO

AIM: The objective of the present case series was to evaluate the 4-year outcomes of implants placed in the esthetic area using static computer-assisted implant surgery (s-CAIS) and restored with a one-abutment one-time (OAOT) protocol using custom-made zirconia abutments and cemented provisional crowns manufactured prior to surgery. Materials and methods: Ten consecutive implants were placed in the esthetic area. Based on a digital implant and prosthodontic planning, surgical guides were ordered and used for the preparation of definitive custom-made zirconia abutments and polymethylmethacrylate provisional crowns. Implants were placed using the s-CAIS guide, and prosthetic components were placed immediately. Implant outcomes were evaluated at the time of surgery, after 4 months, and after 4 years. RESULTS: All implants were successfully placed with s-CAIS and restored with final abutments and provisional crowns. No major prosthetic adverse events were observed. After 4 years, the implant survival rate was 100%, minor peri-implant bleeding on probing was reported, and very stable peri-implant bone levels were observed. The pink esthetic score showed that the prosthetic components were well integrated, and the peri-implant soft tissue was stable. CONCLUSIONS: Within the limitations of the present case series, these results suggest that emerging digital workflows allow the manufacture of final custom-made abutments and provisional crowns prior to surgery. This individualized OAOT procedure may reduce cement-related complications and improve esthetic outcomes by optimizing soft tissue healing with prosthetic components. However, such protocols have evolved toward fully digital workflows, and comparative clinical trials are needed.


Assuntos
Dente Suporte , Estética Dentária , Coroas , Materiais Dentários , Seguimentos , Humanos
6.
Int J Oral Maxillofac Implants ; 37(1): 19-29, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35235616

RESUMO

PURPOSE: This in vitro study evaluated technical outcomes of monolithic zirconia implant-supported fixed dental prostheses (iFDPs) supported by different designs of titanium base abutments after aging and static load testing. MATERIALS AND METHODS: Sixty three-unit monolithic zirconia (yttrium oxide partially stabilized tetragonal zirconia polycrystals; Y-TZP)iFDPs were produced and divided into four groups: group A-conical titanium base abutments for the prosthesis; group B-cylindrical titanium base abutments for the crown; group C-conical titanium base abutment for the prosthesis and cylindrical titanium base abutment for the crown; group D-cylindrical titanium base abutments for the prosthesis. The samples were subjected to an aging protocol and to continuous static loading until failure and analyzed visually and with specific software. The technical outcomes comprised the occurrence of debonding, screw loosening, deformation and fracture, abutment deformation and fracture, implant deformation and fracture, zirconia chipping and fracture, and bending moments. The Pearson chi-squared test (χ2) and Fischer exact test were used to compare the outcomes. The Kolmogorov-Smirnov test was used to evaluate data distribution of the bending moments. Analysis of variance (ANOVA) was used for the analysis of parametric data distribution, and the Kruskal-Wallis test was used for nonparametric data distribution. RESULTS: After aging, a higher percentage of debonding (P = .042) and micromovement (P = .034) was recorded in group C (P = .042). The conical titanium base abutments had a higher debonding (P = .049) and a higher macromovement rate (P = .05). The static load test showed higher bending moments in group D (P = .001) and lower bending moments in group A (P = .001). Debonding was highest in group C (P = .001) and lowest in group A (P = .002). Complete loss of retention rate was highest in group C (P = .001). The conical titanium base abutment had the highest debonding rate (P = .001) and complete loss of retention (P = .001). The micromovement rate was the highest for cylindrical titanium base abutments for the crown (P = .001). The lowest screw loosening, zirconia chipping, and fracture rate (P = .001) and the highest screw deformation (P = .004) were recorded in group A. The screw deformation rate was lowest in the cylindrical titanium base abutments for the crown (P = .008). CONCLUSION: The mixed titanium base abutment design comprising one conical and one cylindrical abutment in Y-TZP iFDPs led to the highest debonding rate. The cylindrical titanium base abutment for the prosthesis provided a lower percentage of debonding and the highest load resistance.


Assuntos
Projeto do Implante Dentário-Pivô , Titânio , Coroas , Dente Suporte , Falha de Restauração Dentária , Análise do Estresse Dentário , Laboratórios , Teste de Materiais , Titânio/química , Zircônio/química
7.
Artigo em Inglês | MEDLINE | ID: mdl-35353086

RESUMO

The present randomized controlled study was undertaken to evaluate and compare peri-implant hard and soft tissue changes between implants restored with multiple disconnections and reconnections of the abutment (control group) vs implants restored with a definitive abutment (test group). Twenty edentulous sites from 13 systemically healthy participants were selected for the study. The recorded clinical parameters were bleeding on probing (BOP) and peri-implant pocket depth (PIPD). The measured radiographic parameter was peri-implant marginal bone loss (PMBL). Two parameters were measured both clinically and by CBCT: distance from the cementoenamel junction to the alveolar crest and alveolar ridge width. At the time of surgery, sites were randomly assigned to either the control or test group. At 6 months, (1) BOP was absent in both groups, (2) PIPD increased in both groups and was significantly greater in the control group, and (3) the mean PMBL was significantly higher in the control group than the test group. Thus, it can be concluded that the use of implants with a definitive abutment could be more beneficial in achieving better maintenance of marginal peri-implant tissue health.


Assuntos
Perda do Osso Alveolar , Implantes Dentários , Carga Imediata em Implante Dentário , Perda do Osso Alveolar/diagnóstico por imagem , Perda do Osso Alveolar/etiologia , Dente Suporte , Implantação Dentária Endo-Óssea , Humanos
8.
Clin Oral Implants Res ; 33(5): 537-547, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35224774

RESUMO

OBJECTIVES: To compare screw-retained and cemented all-ceramic implant-supported single crowns regarding biological and technical outcomes over a 5-year observation period. MATERIALS AND METHODS: In 44 patients, 44 two-piece dental implants were placed in single-tooth gaps in the esthetic zone. Patients randomly received a screw-retained (SR) or cemented (CR) all-ceramic single crown and were then re-examined annually up to 5 years. Outcome measures included: clinical, biological, technical, and radiographic parameters. Data were statistically analyzed with Wilcoxon-Mann-Whitney, Wilcoxon, and Fisher's exact tests. RESULTS: During the observation period, three patients (6.8%) were loss to follow-up. Eight restorations (18.2%, CI (8.2%, 32.7%)) were lost due to technical (6 patients, 13.6% (CI (5.2%, 27.4%)), 2 CR and 4 SR group, intergroup p = .673; implants still present) or biological complications (2 patients, 4.5% (CI (0.6%, 16.5%)), only CR group, intergroup p = .201, both implants lost). This resulted in a survival rate of 81.2% (CI (65.9%, 90.1%)) on the restorative level (18 SR; 15 CR, 3 lost to follow-up). At the 5-year follow-up, the median marginal bone levels were located slightly apical relative to the implant shoulder with 0.4 mm (0.5; 0.3) (SR) and 0.4 mm (0.8; 0.3) (CR) (intergroup p = .582). Cemented restorations demonstrated a significantly higher biological complication rate (36.8%, SR: 0.0%; intergroup p = .0022), as well as a significantly higher overall complication rate (68.4%, SR: 22.7%, intergroup p = .0049). All other outcomes did not differ significantly between the two groups (p > .05). CONCLUSIONS: All-ceramic single-tooth restorations on two-piece dental implants resulted in a relatively low survival rate. Cemented restorations were associated with a higher biological and overall complication rate than screw-retained restorations.


Assuntos
Implantes Dentários para Um Único Dente , Implantes Dentários , Parafusos Ósseos , Coroas , Dente Suporte , Porcelana Dentária , Prótese Dentária Fixada por Implante , Falha de Restauração Dentária , Estética Dentária , Humanos , Zircônio
9.
Clin Oral Implants Res ; 33(4): 377-390, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35113487

RESUMO

OBJECTIVE: To evaluate the long-term integrity of implant-abutment complexes in implant systems with two internal conical angles. MATERIAL AND METHODS: 12,538 bone-level implants of two systems placed between January 2012 and December 2018 were retrospectively analyzed. Cumulative abutment/implant fracture rates in systems with larger (LA, 7.5°) and smaller (SA, 5.7°) internal conical angles were estimated using the Kaplan-Meier analysis and compared between groups. The association between implant systems and jammed abutment retrievability was evaluated by multivariable generalized estimating equation logistic regression modeling. RESULTS: For LA, the 8-year cumulative incident rate was 0.10% (95% confidence interval (CI): 0-0.24%) for implant fracture and 0.26% (95% CI: 0.11%-0.41%) for abutment fracture, demonstrating a significant difference in gender (p = .03), implant diameter (p = .01), jaw (p = .006), and antagonist tooth (p < .001). For SA, the 8-year cumulative incident rate was 0.38% (95% CI: 0-0.79%) for implant fracture and 2.62% (95% CI: 0.05%-5.13%) for abutment fracture, which was influenced by implant diameter (p < .001) and site (p = .03). The cumulative implant/abutment fracture rate was lower for LA implants, particularly for LA implant-supported single crowns (SCs) (p < .05). The abutment-retrieval success rate was 92.9% for LA and 57.1% for SA (p = .055). CONCLUSION: LA implants exhibited a lower incidence of fracture in abutment-implant complexes and a relatively higher retrievability success rate for jammed abutments.


Assuntos
Dente Suporte , Implantes Dentários , Coroas , Projeto do Implante Dentário-Pivô/efeitos adversos , Implantes Dentários/efeitos adversos , Análise do Estresse Dentário , Estudos Retrospectivos
10.
Niger J Clin Pract ; 25(2): 185-191, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35170445

RESUMO

BACKGROUND: Implant supported prosthesis is a common treatment modality. Nowadays, new manufacturing techniques are available to fabricate them. AIMS: To evaluate the effect of different manufacturing techniques of implant supported frameworks (ISF) on the preload of abutment's screws. MATERIALS AND METHODS: A mandibular edentulous acrylic model with four dental implants temporarily stabilized in the interforaminal area was used. One ISF was fabricated using the conventional technique; implants were removed from the model and reassembled into the framework; this framework served as the passively fitting framework (PF). Three additional frameworks were constructed: conventional cast framework (CF), milled framework (MF) and 3D-printed framework (3D-PF). The gap between the frameworks and the neck of the implants were recorded in microns using a digital microscope. A tightening torque (TT) of 35 N·cm was applied to all the four abutments' screws and the screw's preload was recorded using two methods, by strain gauges (SGs) that were attached to the neck of each implant and fed into a stain book in microstrain (µÉ›) and by removal torque (RT) using a digital torque meter. RESULTS: The frameworks' gap means from the lowest to the highest were PF, CF, 3D-PF, and MF. The RT was significantly lower than the TT in all frameworks (P ≤ 0.05). One-way analysis of variance (ANOVA) revealed that the PF had the lowest RT, while the CF and the 3DPF both had the highest RT, and those differences were found to be statistically significantly (P ≤ 0.05). When preload of the frameworks was recorded by SGs, one-way ANOVA revealed that PF had the highest preload value, while both 3D-PF and MF had the lowest preload values, those differences were also found to be statistically significant (P ≤ 0.05). CONCLUSION: The fabrication of implant-supported frameworks using milling or selective laser melting computer aided design/computer-aided manufacturing technologies did not necessarily enhance the screw's preload. This lack of enhancement could be attributed to the great amount of marginal gap in the frameworks fabricated by both techniques.


Assuntos
Implantes Dentários , Mandíbula , Parafusos Ósseos , Desenho Assistido por Computador , Dente Suporte , Prótese Dentária Fixada por Implante , Humanos , Titânio , Torque
11.
J Prosthet Dent ; 127(3): 477.e1-477.e9, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35115162

RESUMO

STATEMENT OF PROBLEM: Dental implant geometry affects the mechanical performance and fatigue behavior of butt-joint implant-supported restorations. However, failure of the implant component has been generally studied by ignoring the prosthetic screw, which is frequently the critical restoration component. PURPOSE: The purpose of this in vitro study was to evaluate the effect of 3 main implant geometric parameters: the implant body diameter, the platform diameter, and the implant-abutment connection type (external versus internal butt-joint) on the fatigue life of the prosthetic screw. The experimental values were further compared with the theoretical ones obtained by using a previously published methodology. MATERIAL AND METHODS: Four different designs of direct-to-implant dental restorations from the manufacturer BTI were tested. Forty-eight fatigue tests were performed in an axial fatigue testing machine according to the International Organization for Standardization (ISO) 14801. Linear regression models, 95% interval confidence bands for the linear regression, and 95% prediction intervals of the fatigue load-life (F-N) results were obtained and compared through an analysis of covariance (ANCOVA) to determine the influence of the 3 parameters under study on the fatigue behavior (α=.05). RESULTS: Linear regression models showed a statistical difference (P<.001) when the implant body diameter was increased by 1 mm; an average 3.5-fold increase in fatigue life was observed. Increasing the implant abutment connection diameter by 1.4 mm also showed a significant difference (P<.001), leading to 7-fold longer fatigue life on average. No significant statistical evidence was found to demonstrate a difference in fatigue life between internal and external implant-abutment connection types. CONCLUSIONS: Increasing the implant platform and body diameter significantly improved (P<.001) the fatigue life of the prosthetic screw, whereas external and internal connections provided similar results. In addition, experimental results proved the accuracy of the fatigue life prediction methodology.


Assuntos
Dente Suporte , Implantes Dentários , Parafusos Ósseos , Projeto do Implante Dentário-Pivô , Falha de Restauração Dentária , Análise do Estresse Dentário , Teste de Materiais
12.
Clin Implant Dent Relat Res ; 24(1): 125-132, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35075756

RESUMO

PURPOSE: To assess the clinical, radiographic, and patient-reported outcome measures, including the success of screw-retained monolithic zirconia implant-supported restorations with CAD/CAM titanium abutments in the posterior region during a 1-year follow-up. METHODS: In a prospective case series, 50 molar sites in the posterior region of 46 patients with a minimum age of 18 years and sufficient bone volume and anatomical conditions for placing an implant (≥8 mm) and an anatomical restoration were included. Parallel-walled implants with a conical connection were inserted in a two-stage surgical procedure. Implant uncovering and healing abutment placement occurred 12 weeks after insertion. Two weeks after mucosa healing, a screw-retained monolithic zirconia restoration with a CAD/CAM titanium abutment was placed. Clinical, radiographic, and patient-reported outcome measures were collected at baseline before implant placement and then during the 1 month and 1 year follow-ups. RESULTS: At the 1 year follow-up, 49 restorations could be evaluated. The plaque accumulation, presence of calculus, bleeding tendency and peri-implant inflammation indices were low, representing healthy peri-implant conditions. The mean marginal bone level change between the 1 month and the 1 year follow-up was -0.17 ± 0.46 mm. The mean patient satisfaction was high. The restoration success was, according to the modified USPHS criteria, 95.9%. CONCLUSION: Monolithic zirconia implant-supported restorations with CAD/CAM titanium abutments have very good clinical, radiographic and patient-reported outcomes after 1 year in function.


Assuntos
Implantes Dentários para Um Único Dente , Titânio , Adolescente , Desenho Assistido por Computador , Coroas , Dente Suporte , Projeto do Implante Dentário-Pivô , Prótese Dentária Fixada por Implante , Humanos , Zircônio
13.
Clin Oral Implants Res ; 33(4): 353-361, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35051314

RESUMO

OBJECTIVES: To compare cemented and screw-retained one-piece zirconia-based restorations in terms of clinical, radiographic, and technical outcomes 5 years after insertion. MATERIALS AND METHODS: Thirty-four patients with single-tooth implants were randomly restored with either a cemented lithium disilicate crown on a one-piece customized zirconia abutment (CEM, 17 patients) or a screw-retained crown based on a directly veneered one-piece customized zirconia abutment (SCREW, 16 patients). All patients were recalled for a baseline examination (7-10 days after crown insertion) and then annually up to 5 years. The following outcomes were assessed: marginal bone level (changes), technical, and clinical (bleeding on probing, plaque control record, probing depth, and keratinized tissue) parameters. The Mann-Whitney U-test was used to assess differences between the two groups. RESULTS: At 5 years, 26 patients (13 in each group) were re-examined. The survival rates on the implant and restorative levels were 100% and 82.4% (equally for both groups), respectively. At 5 years, the median marginal bone level was located at -0.15 mm (IQR: -0.89 mm; 0.27 mm) (CEM) and -0.26 mm (IQR: -0.38 mm; 0.01 mm) (SCREW) below the implant shoulder (intergroup p = .9598). The median changes between baseline and the 5-year follow-up amounted to -0.23 mm (CEM; intragroup p = .0002) and -0.15 mm (SCREW; intragroup p = .1465) (intergroup p = .1690). The overall technical complication rate at 5 years was 15.4% (CEM) and 15.4% (SCREW) (intergroup p = 1.00). Clinical parameters remained stable over time (baseline to 5 years). CONCLUSIONS: At 5 years, screw-retained and cemented restorations rendered largely the same clinical, technical, and radiographic outcomes. Technical complications were frequent in both groups.


Assuntos
Dente Suporte , Implantes Dentários para Um Único Dente , Coroas , Falha de Restauração Dentária , Humanos , Zircônio
14.
PLoS One ; 17(1): e0262582, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35041706

RESUMO

This study aimed to evaluate the effects of two types of provisional resin cements on the color and retentive strength of two different all-ceramic restorations cemented onto customized zirconia abutments. Forty-two crowns were made of monolithic zirconia and lithium disilicate ceramics (n = 21 per group) and cemented on customized zirconia abutments by using two provisional resin cements of TempBond Clear and Implantlink Semi, and TempBond serving as the control (n = 7 per cement subgroup). The specimens' color was measured before and after cementation and after thermocycling. The color difference was calculated by using CIEDE2000 formula (ΔE00). The tensile force was applied to assess the retentive strength. Kruskal-Wallis, Dunn's post-hoc, and Mann-Whitney non-parametric tests were used to compare ΔE00(1) and ΔE00(2) and two-way ANOVA followed by one-way ANOVA and Tukey's HSD post hoc test and T-test were used to compare retentive strength between subgroups. In the lithium disilicate group, ΔE00 of the control subgroup (TempBond) was significantly higher than that of Implantlink Semi cements subgroup (P = 0.001). But, in the monolithic zirconia group, ΔE00 of the control subgroup (TempBond) was significantly higher than that of Implantlink Semi (P = 0.020) and TempBond Clear cements (P = 0.007). In the monolithic zirconia group, the control subgroup (TempBond) was significantly more retentive than TempBond Clear (P = 0.003) and Implantlink Semi cement (P = 0.001). However, in the lithium disilicate group, Implantlink Semi cement was significantly more retentive than TempBond Clear (P = 0.019) and TempBond (control) (P = 0.001). The final color of both restorations was significantly affected by the provisional resin cement type. The retentive strength was influenced by both the type of cement and ceramic.


Assuntos
Cerâmica/química , Cor , Dente Suporte , Retenção em Prótese Dentária/métodos , Teste de Materiais/métodos , Cimentos de Resina/química , Zircônio/química , Cimentação , Desenho Assistido por Computador , Porcelana Dentária/química , Humanos , Propriedades de Superfície
15.
Dent Mater ; 38(3): 508-516, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35063303

RESUMO

OBJECTIVES: Particle generation from implant components caused by frictional wear affect the surrounding peri-implant tissues. The objective of this study was to evaluate the effect of combining implant and abutment materials on wear and particle release in a dynamical loading setup. METHODS: A customized dynamical loading machine was used to subject two implant materials (Titanium and Titanium- Zirconium alloy) paired with two different abutment materials (Titanium and Zirconia) to a cyclic loading set of 240.000 cycles (simulating 1 year of clinical use). The implant and abutment complex was immersed in corrosive liquid to collect particle debris and measure the release of corroded ions. Scanning electron microscopy was used to analyze signs of wear on the components after testing and evaluate the size and composition of particle debris. RESULTS: Wear signs were evident in all material couplings. Particle debris was found on top, inside the implants, and on the abutment heads. The particle size ranged between 0.6 and 16.9 µm, with larger particles composed of Ti. Smaller-sized particles were found in the container liquid ranging from 0.253 to 1.7 µm compared to inside the implants ranging from 3.25 to 95.3 µm. Larger particles were found inside Tizr implants compared to Ti implants. Low levels of ions released due to corrosion were found when measuring content in surrounding liquid. SIGNIFICANCE: Particle generation is evident when subjecting dental implant and abutment couplings in a dynamic loading setup. Internally connected implants hinder the release of larger particles to surrounding container liquid.


Assuntos
Projeto do Implante Dentário-Pivô , Implantes Dentários , Dente Suporte , Materiais Dentários , Análise do Estresse Dentário , Teste de Materiais , Titânio , Zircônio
17.
J Prosthet Dent ; 127(3): 470-476, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33309211

RESUMO

STATEMENT OF PROBLEM: Polyetheretherketone (PEEK) has been advocated to replace metal components in dentistry. Although PEEK is a high-performance polymer with a white color, adequate biological response, and resistance to fracture, data to support PEEK as an alternative material for implant abutments are lacking. PURPOSE: The purpose of this in vitro study was to assess the mechanical and functional properties of PEEK implant abutments as a nonmetallic alternative to titanium abutments, which presents esthetic limitations and greater difficulty to customize clinically. MATERIAL AND METHODS: Implant abutments manufactured by using PEEK (n=24) or titanium grade 5 (n=24) were attached to MIS Implants type M4 3.75×16 mm with an internal screw tightened to 25 Ncm. Screw loosening and microleakage was assessed by submersion in a 2% methylene blue solution for 48 hours at 37 °C. Both groups were compared with and without applying dynamic loading; fatigue testing was performed following the International Organization for Standardization (ISO) 14801:2016 standard. All specimens were observed under a stereomicroscope at ×8 magnification. Statistically significant differences among the PEEK and titanium implant abutments were tested with 2-factor ANOVA and the chi-square analysis for nonpaired and paired data, respectively (α=.05). RESULTS: The implant abutments made of titanium were better in all mechanical tests. The torque loss of titanium abutments was approximately 10%, while PEEK showed a significantly higher (P<.05) torque loss of up to 50%. Moreover, 91.6% of the titanium abutments did not present microleakage, while there was no specimen of PEEK abutments without microleakage, once subjected to dynamic loading (P<.05). CONCLUSIONS: Titanium implant abutments (Ti6Al4V) were better in all tests performed. However, PEEK abutments may be suitable for long-term interim restorations, especially in the anterior area, in patients without parafunction.


Assuntos
Implantes Dentários , Titânio , Benzofenonas , Parafusos Ósseos , Dente Suporte , Projeto do Implante Dentário-Pivô , Falha de Restauração Dentária , Análise do Estresse Dentário , Estética Dentária , Humanos , Teste de Materiais , Testes Mecânicos , Polímeros , Zircônio
18.
J Prosthet Dent ; 127(3): 462-469, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33309295

RESUMO

STATEMENT OF PROBLEM: How axial displacement may be affected by the mechanical properties and internal discrepancy of a cement-retained implant-supported prosthesis is unclear. PURPOSE: The purpose of this in vitro study was to assess the difference in internal discrepancy and axial displacement according to the prosthesis material in cement-retained prostheses splinting nonparallel implants. MATERIAL AND METHODS: Computer-aided design and computer-aided manufacture (CAD-CAM) titanium abutments were fabricated for a vertically placed implant and a 15-degree tilted implant. Three types of prostheses, in zirconia, cobalt-chromium (Co-Cr) alloy, and polymethylmethacrylate resin (PMMA), were fabricated (n=10). The internal discrepancy between the CAD-CAM titanium abutment and the prosthesis was measured by using the replica technique. After luting with an interim cement, they were mounted in Type IV gypsum. The specimens were cyclic loaded, and axial displacement of the prosthesis was measured after 3, 10, 100, and 106 cycles. The internal discrepancy and cumulative axial displacement were assessed by using a 3-way analysis of variance and repeated measures analysis of variance (α=.05). RESULTS: The internal discrepancy of the prosthesis did not differ based on the prosthesis material (P=.869); however, it was significantly different based on the measurement location, with the occlusal discrepancy (224 ±29 µm) being greater than the axial discrepancy (21 ±10 µm) (P<.05). Implants with an angled placement exhibited less axial displacement than implants with vertical placement (P<.05). The PMMA prosthesis demonstrated significantly greater axial displacement than the zirconia or Co-Cr prostheses (P<.05), which were similar (P=.623). CONCLUSIONS: Prostheses made with high-elastic moduli materials exhibited less axial displacement than PMMA prostheses, even though the internal discrepancy was not different. Moreover, vertically placed implants presented a greater axial displacement of the prosthesis than implants with angled placement.


Assuntos
Implantes Dentários , Ligas de Cromo , Desenho Assistido por Computador , Dente Suporte , Cimentos Dentários/uso terapêutico , Materiais Dentários , Planejamento de Prótese Dentária/métodos , Prótese Dentária Fixada por Implante , Zircônio
20.
J Prosthet Dent ; 127(1): 49-54, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33198988

RESUMO

This article describes a technique for fabricating a custom anatomic healing abutment for delayed loaded implants by using the computer-aided design and computer-aided manufacturing (CAD-CAM) technology from a polymethyl methacrylate (PMMA) blank. The dimensions of the custom healing abutment are measured from a conventional dental radiograph and diagnostic casts. The healing abutment is used in the second surgical stage to guide soft tissue healing. The resulting soft tissue contour guides the design of the mucosal part of the custom implant abutment.


Assuntos
Implantes Dentários , Desenho Assistido por Computador , Dente Suporte , Projeto do Implante Dentário-Pivô , Titânio
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