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AIMS: To evaluate and compare the distribution of stress patterns around a single implant-supported crown with various abutment designs using different abutment materials. SETTING AND DESIGN: This is an in vitro study to evaluate and compare stress distribution patterns. METHODS: The three-dimensional (3D) finite element models included four stock and four customized abutments made of Titanium, Zirconia, Fibre-Reinforced Composite, and Poly Ether-Ether Ketone (PEEK) attached to an end-osseous root form implant. The models were subjected to a 300 N vertical load at the central fossa and a 150 N oblique load at the centre of the lingual inclines of the buccal cusps of the mandibular molar crown designed on the model. STATISTICAL ANALYSIS USED:  The stress distribution within the implant and the surrounding supporting structures was evaluated using finite element analysis. RESULTS: In all the models, stresses on the implants were observed to be concentrated in the neck of the implants in the first few threads. Irrespective of the abutment design, PEEK abutment transferred greater stresses to implants and Zirconia abutment transferred lesser stresses to implants. In the implants, the customized abutment showed lesser stress values than the stock abutment during oblique loading. CONCLUSIONS: Stresses on implants and cortical bone can be reduced by using Zirconia as an abutment material compared to Titanium, Fibre-Reinforced Composite, and Poly Ether-Ether Ketone material. Customized abutments improve the load transfer between the prosthesis and the implant and the surrounding bone, lessen the micro-movement of the abutments, and distribute the stress more evenly across the implant's component parts.

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The optimal configuration of a customized implant abutment is crucial for bone remodeling and is influenced by various design parameters. This study introduces an optimization process for designing two-piece zirconia dental implant abutments. The aim is to enhance bone remodeling, increase bone density in the peri-implant region, and reduce the risk of late implant failure. A 12-month bone remodeling algorithm subroutine in finite element analysis to optimize three parameters: implant placement depth, abutment taper degree, and gingival height of the titanium base abutment. The response surface analysis shows that implant placement depth and gingival height significantly impact bone density and uniformity. The taper degree has a smaller effect on bone remodeling. The optimization identified optimal values of 1.5 mm for depth, 35° for taper, and 0.5 mm for gingival height. The optimum model significantly increased cortical bone density from 1.2 to 1.937 g/cm3 in 2 months, while the original model reached 1.91 g/cm3 in 11 months. The standard deviation of density showed more uniform bone apposition, with the optimum model showing values 2 to 6 times lower than the original over 12 months. The cancellous bone showed a similar trend. In conclusion, the depth and taper have a significant effect on bone remodeling. This optimized model significantly improves bone density uniformity.

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Personalized medicine has become an important direction to offer better solutions for health problems. In implantology, this trend was materialized through customizing dental abutments to each clinical situation. The demands for better esthetics and function of implant-supported restorations have imposed a more personalized variety of prosthetic abutments. This retrospective study compared clinical efficiency of personalized implant abutments with standard implant abutments in multiple implant restorations. Clinical data of patients who were admitted in a private clinic between 2011 and 2022 and received dental implant treatments were collected. All complications and undesired events from the patients' medical record charts were statistically analyzed. The implants were loaded using either standard or customized abutments. For complete arch rehabilitations with the SKY Fast & Fixed protocol, standard titanium prosthetic abutments were used. Our results suggest that the abutments choice for patients has moved throughout the years more towards the use of customized abutments. The number of customized abutments (414) was higher compared with the number of standard abutments (293). In our database, the most used abutments for the anterior area implants were made of titanium and zirconia, whereas for the posterior area, the preferred abutments were mostly titanium. The standard abutments were used almost entirely for immediate loading and implantation in both anterior and posterior areas (Fast & Fixed protocol). Complications were encountered mainly in restorations with standard abutments (9.22%) compared to customized abutments (2.7%), with titanium abutments being the most reliable, having only 1.79% complications.

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This study presented a rehabilitation option for malpositioned implants; this involved obtaining their position and inclination through intraoral scanning, and producing a customized abutment with CAD/CAM technology. The patient in this case report presented a root fracture in tooth 21 and was subjected to extraction, implant installation, and immediate provisional prosthesis. The implant was installed with a distal inclination due to anatomical limitations. After osseointegration, an intraoral scanning transfer provided a digital model (file extension .stl), which reproduced the implant's position and inclination. Then, the file was sent so that a customized abutment (CAD/CAM) could be manufactured, promoting the final rehabilitation of the case; this allowed for good hygiene, load distribution in the dynamic interocclusal relationship, and favorable esthetics, whereas many would otherwise recommend implant removal. The result presented lower costs, a shorter time frame, and a lower morbidity for the patient.

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PURPOSE: The aim of this review was to evaluate the survival rates of restorations utilizing titanium base abutments (TBA) for restoring single-unit implant prostheses. MATERIALS AND METHODS: This review was conducted following the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines. The focus question was: In patients who require the restoration of a single dental implant utilizing a titanium base abutment, what are the determining factors and outcomes relating to implant prosthesis prognosis and survival? A comprehensive search of databases (PubMed, EMBASE, and Cochrane Library) was conducted on 16 April 2023 and updated on 5 May 2023. Randomized clinical trials (RCT), retrospective studies and prospective studies, reporting on the use of TBA for single implant prostheses, were reviewed. A Cochrane collaboration risk of bias assessment analysis was performed for randomized clinical studies, and the Newcastle-Ottawa Scale tool was applied for non-randomized studies. A meta-analysis was performed on clinical trials reporting on survival rates of both TBA and other abutments. Other clinical studies, reporting on TBA only, were included for descriptive statistics. RESULTS: The search provided 1159 titles after duplicates were removed. Six RCTs were included to perform a meta-analysis and compare the survival of the TBA to other abutments [OR 0.74; 95% CI: 0.21-2.63, heterogeneity; I2 0%; p = .99]. Twenty-three prospective and retrospective studies fulfilled the criteria and were included in the meta-analysis after 12 months of function. A total of 857 single implant-supported prostheses fabricated with a TBA were included. TBA abutments have an estimate 98.6% survival rate after 1 year in function (95% CI: 97.9%-99.4%). The mean follow-up period was 31.2 ± 16.9 months. CONCLUSIONS: Single implant prosthesis restored with titanium base abutments showed favourable short-term survival rates.

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PURPOSES: The aim of the present clinical and radiologic retrospective study was to evaluate alveolar bone remodeling, in terms of alveolar width and peri­implant bone level, two years after immediate implant positioning (with two different collar lengths, 0.8 mm and 2.0 mm) and loading of preformed healing cap. The Null hypothesis, H0 is: there was no difference between the two groups of implants. METHODS: Patients suffering from single-tooth edentulous areas in premolar, cuspid, and incisive areas were treated with fresh-socket implants and immediate preformed anatomical healing caps. Each final crown restoration was fabricated 3 months later. Primary outcomes (related to loss of the alveolar width and peri­implant bone level) and secondary outcomes (testing adverse events, and measuring implant/prosthesis survival) were acquired and analyzed. RESULTS: A two-year retrospective analysis was conducted on 31 patients (19 female and 12 male), who underwent dental implant placement with implants having two different lengths of the collar: group A, 0.8 mm, and group B, 2.0 mm. As for the width of the alveolar crest, there was a negligible loss (less than half a millimeter) reported for both the groups, anyway reaching a statistical significance. Preoperative alveolar widths (9.50±0.67 mm and 9.45±0.90 mm, respectively for groups A and B) were different from the two-year alveolar widths (9.20±0.74 mm and 8.93±0.99 mm, respectively for groups A and B) with p-values ≤ 0.0049. When the marginal bone loss was assessed, significant differences were registered between the two procedure groups (-1.42±0.34 mm for group A and -0.11±0.15 mm for group B with a p-value < 0.0001). CONCLUSIONS: The proper design of a healing abutment was very important to preserve the emergence profile immediately after extraction and implant placement. The length of the implant collar used with an immediate healing abutment appeared to affect the preservation of the alveolar crest with predictable final results.

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PURPOSES: To investigate the amount of first-year peri­implant bone loss and the development of the papillae when delayed dental implants loaded with anatomic cover screw and those underwent conventional healing protocol were compared. METHODS: Edentulous healed sites had undergone delayed implants placement. In the anatomical cap group, patients were treated with a guided tissue healing, tooth-like cross-linkable acrylic resin caps had been immediately screwed on dental implants. The marginal loss of the alveolar bone height 1 year after surgery and Jemt's papillae index were obtained. Non-parametric statistics were performed with a level of significance of 1% RESULTS: Forty patients were included in the present retrospective analysis. After a follow-up of 1 year, none of the 40 included implants showed a failure. The Jemt's papilla index was 1.76±0.44 and 1.34±0.50 respectively for guided tissue healing and conventional healing group, without any significant difference. Within the first year of survey a bone loss of -1.27±0.26 mm for conventional healing treatment showed a statistically significant difference (p-value<0.0001) when it was compared to the negligible of the other group (-0.06±0.31 mm). CONCLUSIONS: A guided healing procedure with preformed caps seemed to give better outcomes regarding marginal bone loss and papilla index than those of conventional abutments.

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AIM: To determine the 3-year clinical and dimensional change of the soft tissue following implant placement in healed sites before and after loading with either customized or conventional healing abutments. MATERIALS AND METHODS: Premolar/molar implants were immediately loaded with either provisional and customized abutments without finishing lines according to principles of the Biologically Oriented Preparation Technique (BOPT), test group, or conventional healing abutments, control group. Three months later, the definitive crowns were fabricated. Primary outcomes (changes in the soft tissue) and secondary outcomes (adverse events) had been registered. RESULT: Fifty out of 87 subjects originally included were finally selected for this retrospective analysis: 23 in the test and 27 in the control group. During the first days after surgery 2 adverse events of mucositis, one for each group, occurred. A Few technical complications such as unscrewing 4 screw-retained crowns were recorded. A significant increase in the alveolar width was observed in both groups (test = +2.5±0.5mm, and control = +1.0±0.9mm). The widths appeared to not be merely changed from 3 months to 3 years in both groups. There were no significant differences regarding the width of the keratinized mucosa measured at baseline and after follow-up. Jemt papilla index showed a higher increase in the test group compared with that of the control group. CONCLUSION: Within 3 years of the follow-up period, peri-implant soft tissue outcomes of single, immediately loaded implants with customized healing abutments showed better results in terms of thickness and width when they were compared with those of the conventional group. Side effects count (mucositis and dehiscence) appeared to be very similar between the two groups. In addition, customized healing abutments led to significant augmentation of the alveolar width more than twice that registered in the conventional group.

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The misplacement of implants represents an unfavorable complication in dental implant prostheses. Numerous instances necessitating restorative intervention, colloquially termed "rescue cases," encompass either novel occurrences or reconstructions of irreversible implant scenarios. A viable solution for addressing these prosthesis-related challenges is using cementable options. This issue is directly linked to improperly placed implants, which dentists find challenging to rectify due to the absence of angle-correcting abutments from manufacturers. In such situations, the preferred treatments involve either Implant Innovations' universal castable long abutment (UCLA) (Palm Beach Gardens, Florida, United States) or a customized abutment fashioned from the titanium alloy impression coping for the Core-Vent implant (Paragon, Calabasas, California, United States). The Department of Prosthodontics received a referral for a patient with an anterior implant that had been misplaced and required rehabilitation. This case report outlines the chosen treatment approach for an implant situated buccally.

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The aim of this report is to present a digital workflow technique to design a customized abutment for provisionalization of an immediate-placed implant based on the natural emergence profile of the tooth to be extracted. The workflow involves the combination of intraoral and CBCT scans, from which three-dimensional (3D) reconstructions of soft tissue and alveolar bone, as well as of the tooth to be extracted are obtained and exported as STL files. The files are imported to a computer-aided design (CAD) software, in which a virtual wax-up and custom abutment design are performed considering the natural emergence profile of the patient's tooth prior to extraction. Since the customized abutment is digitally designed, it can also be used as a scan body, to be directly scanned intraorally after soft tissue healing around an interim implant restoration. The custom abutment digitally designed can be then produced by milling zirconia with an optimally chosen color, in accordance with the aesthetic needs of the patient.

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Screw-retained implant restorations have an advantage of predictable retention, retrievability, and lack of potentially retained subgingival cement. However, a few disadvantages exist such as need for precise placement of the implant for optimal and esthetic location of the screw access hole and obtaining passive fit. Malo bridge with customization of abutment can establish a precise patient's gingival architecture. It is the most esthetically advanced form of fixed prosthodontic rehabilitation for complete and partially edentulous patients. This prosthesis is combined with three-dimensional (3D)-printed computer-aided design and computer-aided manufacturing technology to gain the precise fit and added esthetics. It also has advantages such as elimination of screw access openings, makes it possible to remove and repair the fractured porcelain of the individual crown without removing the whole structure, excellent precision, avoids casting errors, light weight, reduced complexity of laboratory procedures, high definition of morphology, and time-consuming. This case report presents replacement of partially edentulous maxilla using 3D-printed Malo bridge.

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In addition to restoring oral function, stable aesthetic outcome has become the goal of oral implant therapy. To ensure the harmonious appearance of the restoration and the natural tooth and to obtain the ideal hard and soft tissue structure, clinicians should have a clear understanding of the factors that influence the success of aesthetics and apply different technique accordingly. In view of the recent progress in the field of oral implant, the factors affecting the aesthetic outcome of implant treatment were discussed including neck design of implant, design of customized abutment, tissue regeneration and gingival papilla height, so as to provide clinical reference to improving the aesthetic outcome of oral implant treatment.

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Objective: To observe the changes of peri-implant tissue around the individualized abutment that was grinded from zirconia provisional crown in one year. Methods: In this research, a prosthodontic-driven virtual implant planning and immediate provisionalization were conducted in computer assisted design software. And computer-aided design/computer-aided manufacturing (CAD/CAM) techniques were used to fabricate the zirconia provisional crown and surgical guide template before surgery. The implant was accurately placed with the surgical guide, and the zirconia provisional crown was immediately delivered after surgery. Three months later, the implant osseointegration was completed, and zirconia provisional crown was prepared intraorally to generate customized zirconia abutment for final prosthesis. The study included 30 patients with single anterior tooth loss, including 18 males and 12 females, aged from 26 to 50 years old, and the mean age was (36.2±6.1) years old. The patients were from the Center of Oral Implantology, The First Affiliated Hospital of Zhejiang University Medical College from January 2017 to February 2018. After cementation of the final prosthesis, the cases were followed up at 6 and 12 months time intervals. Implant survival rate, probing depth, bleeding on probing, marginal bone level loss and papilla index score (PIS) were recorded in every appointment. Results: The survival rate of 30 implants was 100%, and the probing depths were less than 5 mm. The bone resorption at 6 and 12 months follow-up after the final delivery was 0 (0, 0) mm and 0 (-0.2, 0) mm, respectively, and the difference was not statistically significant (P>0.05). The PIS was 3.0 (2.0, 4.0), 3.0 (2.8, 4.0) and 3.0 (3.0, 4.0) on the final delivery, 6 and 12 months after final delivery, respectively. Conclusions: Marginal bone level and bone loss were stable with this new implant clinical protocol at the one-year follow-up.

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AIM: To evaluate width loss of the alveolar ridge three years after implant placement in a fresh extraction socket following two different tissue healing methodologies: conventional healing procedure vs CAD/CAM technology for a customized healing abutment. MATERIALS AND METHODS: Post-extraction sockets underwent immediate dental implant placement without the voids being filled between the implant surface and the socket wall. Samples (one implant per patient) were retrospectively enrolled in each group according to the type of healing procedure: implants in the conventional group underwent standard closed healing with a cover screw, while in the customized group the healing abutment was immediately screwed onto the head of the implant, mimicking the look of the extracted tooth fabricated by CAD/CAM technology. The width of the alveolar ridge was measured on 3D radiographs at baseline (before surgery) and three years postsurgery. Nonparametric statistics were performed with a significance level of 0.01. RESULTS: A total of 54 dental implants were selected. An implant survival rate of 100% was reported for all implants after 36 months. Three years after implant placement, loss in bone width was registered for both the conventional and customized groups, being 2.2 (1.1) and 0.2 (0.7) mm, respectively. Changes in the customized group were significantly lower than in the conventional group. Significant differences were again found between the groups for each of the tooth sites. Loss of bone width appeared negligible (from incisor to premolar), with values ranging between 0.2 and 0.4 mm in the customized group, whereas in the conventional group all tooth sites underwent wide shrinkage (with a bone loss ranging from 1.6 to 3.0 mm). CONCLUSION: The CAD/CAM procedure might provide the following advantages: 1) Stabilization of the gingival setting and bone volume in a fresh socket implant; 2) Maintaining the same emergence profile of teeth for restorative crowns, avoiding laboratory approximation of the emergence profile of the definitive restoration; and 3) Optimal prosthetic-surgical planning and minimally invasive extraction to preserve the integrity of the supporting tissue.

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PURPOSE: To compare abutment displacement between the virtual, customized abutment that was designed on a cast and the customized abutment prepared in the oral cavity. MATERIALS AND METHODS: Eleven patients were selected for a single posterior implant prosthetic treatment. The impression was obtained using the closed tray impression method with a vinyl polysiloxane material using a custom tray. The standard tessellation language files of the customized abutment that was designed using the computer-aided design system and acquired with an intraoral scanner in the oral cavity were superimposed and analyzed for distance and angle displacement using the three-dimensional inspection analysis program (Geomagic Control X). In the statistical analysis, distance and angle displacement values were analyzed with the Kruskal-Wallis H test (α = 0.05), and a post hoc comparison was performed using the Mann-Whitney U-test and Bonferroni correction method. RESULTS: The mean distance and angle displacement of the 15 customized abutments were 89.52 ± 66.86 µm and 0.83 ± 1.21°, respectively. There were significant differences in distance displacement (p < 0.001), and angle displacement (p < 0.001) among the 15 customized abutments, and there were no significant differences in angle displacement along the 4 directions (p = 0.735). CONCLUSIONS: The displacement values of the customized abutments evaluated in the oral cavity differed significantly from patient to patient.

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PURPOSE: This study evaluated the usability of and satisfaction with two types of computer-aided design (CAD) software among users who had experience with dental implant CAD software and those who did not. MATERIALS AND METHODS: Dental technicians (n = 20) who had previous experience with dental implant CAD Software and students from the College of Dentistry (n = 12) who had never designed implant custom abutments were asked to evaluate two types of CAD Software, Exocad and Deltanine. In addition, the participants were asked to fill out a structured questionnaire (Section 1: Entering basic information and retrieving files; Section 2: Setting conditions before abutment design; Section 3: Setting abutment design; and Section 4: Overall satisfaction). For the statistical analysis of the collected data, Mann-Whitney U test was used (α = .05). RESULTS: The ease of design and satisfaction with the implant CAD Software, evaluated with respect to 21 statements divided into four Stages, were significantly higher for Exocad in both groups for Secion 1. For Sections 2 and 3, participants with experience evaluated Deltanine to be significantly better. For Section 4, both groups evaluated Exocad Software to be better. CONCLUSION: Overall, the Exocad Software was evaluated as having better usability and offering greater satisfaction. However, in terms of performance in the core of the design process, i.e. Sections 2 and 3, Deltanine was rated higher by the experienced users. Thus, if the user interface design parts are supplemented, Deltanine CAD Software could be put to a wider use in clinics.

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The individuals who have been afflicted with mandibular defects involving soft and hard tissue loss are subjected to functional, psychological and social consequences. Rehabilitation is of prime importance in restoring self confidence and improving the quality of life. Complex mandibular defects can be successfully rehabilitated with the three dimensional (3D) computerized diagnostic technique (Simplant-Dentsply sirona implant). one of the important tools for measuring the oral health status by scale knows as oral health impact profile (OHIP). OHIP is a scale particularly designed to measure the quality of life and its influence pertaining to functional and psychological aspects. This report describes the prosthetic rehabilitation posttraumatic mandibular defect with 3D SimPlant software and stereolithography. With the application of computer-aided design/computer-aided manufacturing technology, guided implant prosthesis could definitely improve masticatory performance and esthetics, thereby enhancing oral health-related quality of life.

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BACKGROUND: While working on CAD/CAM-customized abutments, the use of standard impression copings with a circular diameter produces inconsistency within the emergence profile. It may begin with a collapse of the supra-implant mucosa during impression taking, then lead to a computer-generated mismatch of the position and outline of the abutment shoulder, and consequently result in a compromised outcome of anticipated treatment. The aim of the study was to compare the virtual and clinical positions of the abutment shoulder in relation to the mucosal margin after the abutment delivery. METHODS: Conventional open-tray impression takings followed uncovering surgery. Master casts were scanned with a desktop scanner. Clinical examinations took place after abutment's insertion and temporization (T1) and prior to cementation of the definitive crown (T2). The distances between the abutment shoulder and marginal soft tissue were measured intraorally in four aspects and juxtaposed with those on the virtual model. RESULTS: The study evaluated 257 dental implants and CAD/CAM-customized abutments. As T1 and T2 showed, there was a positive correlation between the virtually designed abutment shoulder position and matching clinical location relative to the mucosal margin. In 42.1% of cases, the distance between the mucosal margin and the abutment shoulder did not change. It increased in 36.3% of cases while a decrease occurred in 21.6% of them. CONCLUSIONS: Computer-set position of the abutment shoulder in relation to the mucosal margin can be predictably implemented in clinical practice.

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PURPOSE: The purpose of this study is to assess the relationship between the time spent designing custom abutments and repeated learning using dental implant computer aided design (CAD) software. MATERIALS AND METHODS: The design of customized abutments was performed four stages using the 3DS CAD software and the EXO CAD software, and measured repeatedly three times by each stage. Learning effect by repetition was presented with the learning curve, and the significance of the reduction in the total time and the time at each stage spent on designing was evaluated using the Friedman test and the Wilcoxon signed rank test. The difference in the design time between groups was analyzed using the repeated measure two-way ANOVA. Statistical analysis was performed using the SPSS statistics software (P < 0.05). RESULTS: Repeated learning of the customized abutment design displayed a significant difference according to the number of repetition and the stage (P < 0.001). The difference in the time spent designing was found to be significant (P < 0.001), and that between the CAD software programs was also significant (P = 0.006). CONCLUSION: Repeated learning of CAD software shortened the time spent designing. While less design time on average was spent with the 3DS CAD than with the EXO CAD, the EXO CAD showed better results in terms of learning rate according to learning effect.

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In patients with fully edentulous maxilla, fabrication of implant-supported overdenture can be a viable treatment option, when a minimum of six implants were strategically placed. Among several attachment systems used for implant-supported overdentures, milled-bars prevent rotational movement of denture, thus showing great stability, and have the advantage of splinting multiple implants with each other. In this case report, a milled-bar supported overdenture was fabricated for a patient suffering from condition of fully edentulous maxilla with severe ridge resorption in the anterior residual ridge. Seven implants composed of three different systems were effectively utilized by CAD/CAM customized abutment and cement-retained milled bar.

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