Hausdörfer, Tim

[["dc.bibliographiccitation.journal","Clinical Oral Investigations"],["dc.contributor.author","Rinke, Sven"],["dc.contributor.author","Zuck, Tanja"],["dc.contributor.author","Hausdörfer, Tim"],["dc.contributor.author","Leha, Andreas"],["dc.contributor.author","Wassmann, Torsten"],["dc.contributor.author","Ziebolz, Dirk"],["dc.date.accessioned","2021-09-01T06:42:27Z"],["dc.date.available","2021-09-01T06:42:27Z"],["dc.date.issued","2021"],["dc.description.abstract","Abstract Objectives A university-based randomized clinical study evaluated the 5-year performance of chairside-fabricated zirconia-reinforced lithium silicate (ZLS)-ceramic partial crowns. Material and methods Forty-five patients were restored with 61 chairside-fabricated ZLS-restorations (Cerec SW 4.2, Dentsply Sirona, Germany; Vita Suprinity, Vita Zahnfabrik, Germany). Deviating from the manufacturers’ recommendations, restorations with reduced minimum material thicknesses (MMT) were fabricated: group 1, MMT = 0.5–0.74 mm ( n  = 31); group 2, MMT = 0.75–1.0 mm ( n  = 30). For luting, a self-adhesive cement (SAC) or a total-etch technique with a composite cement (TEC) was applied. Statistical evaluation was performed by time-to-event analysis (Kaplan–Meier). Possible covariates of the survival (SVR) and success rates (SCR), evaluated in a Cox regression model, were MMT, restoration position (premolar/molar), and cementation technique (SAC vs. TEC). Results Forty patients (54 restorations, premolars, n  = 23; molars, n  = 31) participated in the 5-year follow-up. Five losses due to ceramic fractures occurred in group 1 ( n  = 28) (SVR: 83.0% [95% confidence interval (CI): 0.71–0.96]). Group 2 ( n  = 26) showed no losses (SVR: 100%). The success rate for partial crowns placed on premolars was 100% and 69% (95% CI: 0.54–0.84) for molar restorations. Recementation was required in 4 restorations with SAC (SCR: 86% [95% CI: 0.73–0.99]; SCR-DC: 100%). Restorations in group 2 showed a significantly reduced risk of material fracture hazard ratio (HR) = 0.09, p  = 0.0292) compared with the restorations in group 1. Molar partial crowns showed an increased risk for a clinical intervention (HR = 5.26, p  = 0.0222) compared to premolar restorations. Conclusions Material thickness and position of the restoration are risk factors influencing the survival and success rate of ZLS-ceramic partial crowns. Clinical relevance Observation of an MMT of at least 0.75–1.0 mm for ZLS-ceramics is essential to avoid material-related fractures. Clinical trial registration : German Clinical Trails Register (trial number: DRKS00005611)"],["dc.description.abstract","Abstract Objectives A university-based randomized clinical study evaluated the 5-year performance of chairside-fabricated zirconia-reinforced lithium silicate (ZLS)-ceramic partial crowns. Material and methods Forty-five patients were restored with 61 chairside-fabricated ZLS-restorations (Cerec SW 4.2, Dentsply Sirona, Germany; Vita Suprinity, Vita Zahnfabrik, Germany). Deviating from the manufacturers’ recommendations, restorations with reduced minimum material thicknesses (MMT) were fabricated: group 1, MMT = 0.5–0.74 mm ( n  = 31); group 2, MMT = 0.75–1.0 mm ( n  = 30). For luting, a self-adhesive cement (SAC) or a total-etch technique with a composite cement (TEC) was applied. Statistical evaluation was performed by time-to-event analysis (Kaplan–Meier). Possible covariates of the survival (SVR) and success rates (SCR), evaluated in a Cox regression model, were MMT, restoration position (premolar/molar), and cementation technique (SAC vs. TEC). Results Forty patients (54 restorations, premolars, n  = 23; molars, n  = 31) participated in the 5-year follow-up. Five losses due to ceramic fractures occurred in group 1 ( n  = 28) (SVR: 83.0% [95% confidence interval (CI): 0.71–0.96]). Group 2 ( n  = 26) showed no losses (SVR: 100%). The success rate for partial crowns placed on premolars was 100% and 69% (95% CI: 0.54–0.84) for molar restorations. Recementation was required in 4 restorations with SAC (SCR: 86% [95% CI: 0.73–0.99]; SCR-DC: 100%). Restorations in group 2 showed a significantly reduced risk of material fracture hazard ratio (HR) = 0.09, p  = 0.0292) compared with the restorations in group 1. Molar partial crowns showed an increased risk for a clinical intervention (HR = 5.26, p  = 0.0222) compared to premolar restorations. Conclusions Material thickness and position of the restoration are risk factors influencing the survival and success rate of ZLS-ceramic partial crowns. Clinical relevance Observation of an MMT of at least 0.75–1.0 mm for ZLS-ceramics is essential to avoid material-related fractures. Clinical trial registration : German Clinical Trails Register (trial number: DRKS00005611)"],["dc.identifier.doi","10.1007/s00784-021-04132-y"],["dc.identifier.pii","4132"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/89055"],["dc.language.iso","en"],["dc.notes.intern","DOI-Import GROB-455"],["dc.relation.eissn","1436-3771"],["dc.relation.issn","1432-6981"],["dc.title","Prospective clinical evaluation of chairside-fabricated zirconia-reinforced lithium silicate ceramic partial crowns—5-year results"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","1245"],["dc.bibliographiccitation.issue","6"],["dc.bibliographiccitation.journal","The Journal of Prosthetic Dentistry"],["dc.bibliographiccitation.lastpage","1251"],["dc.bibliographiccitation.volume","128"],["dc.contributor.author","Lechte, Clemens"],["dc.contributor.author","Hausdörfer, Tim"],["dc.contributor.author","Kanzow, Philipp"],["dc.contributor.author","Rödig, Tina"],["dc.contributor.author","Wiegand, Annette"],["dc.date.accessioned","2022-12-01T08:30:42Z"],["dc.date.available","2022-12-01T08:30:42Z"],["dc.date.issued","2022-11-04"],["dc.description.abstract","Statement of problem: Less-experienced operators have been shown to require additional training to achieve results similar to those of experienced operators. However, clinical data comparing the survival and success of ceramic restorations by experienced and less-experienced operators by using the computer-aided design and computer-aided manufacturing (CAD-CAM) technology are lacking.\r\nPurpose: The purpose of this retrospective clinical study was to analyze and compare the clinical performance of CAD-CAM lithium disilicate restorations fabricated by less-experienced (predoctoral dental students) and experienced (dentists) operators.\r\nMaterial and methods: Patients who received an adhesively luted CAD-CAM lithium disilicate restoration between 2011 and 2019 were included in the study. Clinical performance was assessed by calibrated examiners by using World Dental Federation (FDI) criteria. Success and survival were calculated by the Kaplan-Meier method and statistically compared by log-rank tests and univariate Cox regression analyses. FDI criteria were compared by using Mann-Whitney-U tests (α=.05).\r\nResults: Ninety-two restorations (students: n=65, dentists: n=27) were assessed (mean ±standard deviation time from insertion: 4.04 ±1.55 years). The survival rates after 2 years (students: 93.8%, mean annual failure rate [mAFR]: 3.1%; dentist: 96.3%, mAFR: 1.9%) and after 4 years (students: 87.3%, mAFR: 3.3%; dentists: 88.3%, mAFR: 3.1%) were not significantly different (P=.525). Also, success rates after 2 (students: 90.8%, mAFR: 4.7%; dentists: 92.6%, mAFR: 3.8%) and 4 years (students: 82.4%, mAFR: 4.7%; dentists: 76.1%, mAFR: 6.6%) were not significantly different (P=.778). FDI criteria were also not significantly different between less-experienced and experienced operators (P≥.110).\r\nConclusions: Operator experience did not affect the short-term clinical performance of CAD-CAM lithium disilicate restorations."],["dc.identifier.doi","10.1016/j.prosdent.2022.09.011"],["dc.identifier.pii","S0022391322006242"],["dc.identifier.pmid","36344298"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/117957"],["dc.language.iso","en"],["dc.notes.intern","DOI-Import GROB-621"],["dc.relation.issn","0022-3913"],["dc.relation.orgunit","Poliklinik für Präventive Zahnmedizin, Parodontologie und Kariologie"],["dc.rights.uri","https://www.elsevier.com/tdm/userlicense/1.0/"],["dc.title","Clinical performance of CAD-CAM partial-coverage restorations: Experienced versus less-experienced operators"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.subtype","original_ja"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","580"],["dc.bibliographiccitation.issue","6"],["dc.bibliographiccitation.journal","International Endodontic Journal"],["dc.bibliographiccitation.lastpage","589"],["dc.bibliographiccitation.volume","45"],["dc.contributor.author","Roedig, Tina"],["dc.contributor.author","Hausdoerfer, T."],["dc.contributor.author","Konietschke, Frank"],["dc.contributor.author","Dullin, Christian"],["dc.contributor.author","Hahn, Wolfram"],["dc.contributor.author","Huelsmann, Micbael"],["dc.date.accessioned","2018-11-07T09:10:06Z"],["dc.date.available","2018-11-07T09:10:06Z"],["dc.date.issued","2012"],["dc.description.abstract","Rodig T, Hausdorfer T, Konietschke F, Dullin C, Hahn W, Hulsmann M. Efficacy of D-RaCe and ProTaper Universal Retreatment NiTi instruments and hand files in removing gutta-percha from curved root canals a micro-computed tomography study. International Endodontic Journal, 45, 580589, 2012. Abstract Aim To compare the efficacy of two rotary NiTi retreatment systems and Hedstrom files in removing filling material from curved root canals. Methodology Curved root canals of 57 extracted teeth were prepared using FlexMaster instruments and filled with gutta-percha and AH Plus. After determination of root canal curvatures and radii in two directions, the teeth were assigned to three identical groups (n = 19). The root fillings were removed with D-RaCe instruments, ProTaper Universal Retreatment instruments or Hedstrom files. Pre- and postoperative micro-CT imaging was used to assess the percentage of residual filling material as well as the amount of dentine removal. Working time and procedural errors were recorded. Data were analysed using analysis of covariance and analysis of variance procedures. Results D-RaCe instruments were significantly more effective than ProTaper Universal Retreatment instruments and Hedstrom files (P < 0.05). Hedstrom files removed significantly less dentine than the rotary NiTi systems (P < 0.0001). D-RaCe instruments were significantly faster compared to both other groups (P < 0.05). No procedural errors such as instrument fracture, blockage, ledging or perforation were detected in the Hedstrom group. In the ProTaper group, four instrument fractures and one lateral perforation were observed. Five instrument fractures were recorded for D-RaCe. Conclusions D-RaCe instruments were associated with significantly less residual filling material than ProTaper Universal Retreatment instruments and hand files. Hedstrom files removed significantly less dentine than both rotary NiTi systems. Retreatment with rotary NiTi systems resulted in a high incidence of procedural errors."],["dc.identifier.doi","10.1111/j.1365-2591.2012.02014.x"],["dc.identifier.isi","000303802400011"],["dc.identifier.pmid","22264204"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/26417"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Wiley-blackwell"],["dc.relation.issn","0143-2885"],["dc.title","Efficacy of D-RaCe and ProTaper Universal Retreatment NiTi instruments and hand files in removing gutta-percha from curved root canals - a micro-computed tomography study"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","943"],["dc.bibliographiccitation.issue","9"],["dc.bibliographiccitation.journal","Journal of Dental Education"],["dc.bibliographiccitation.lastpage","948"],["dc.bibliographiccitation.volume","82"],["dc.contributor.author","Hausdörfer, Tim"],["dc.contributor.author","Kanzow, Philipp"],["dc.contributor.author","Tschammler, Claudia"],["dc.contributor.author","Herrmann, Manfred"],["dc.contributor.author","Wiegand, Annette"],["dc.date.accessioned","2019-02-14T11:45:56Z"],["dc.date.accessioned","2020-05-22T07:02:52Z"],["dc.date.available","2019-02-14T11:45:56Z"],["dc.date.available","2020-05-22T07:02:52Z"],["dc.date.issued","2018"],["dc.description.abstract","The aim of this study was to evaluate dental students' retention of factual and procedural knowledge gained in a preclinical course in operative dentistry during a clinical dental curriculum. In 2017, all 157 seventh- to tenth-semester dental students at a dental school in Germany were asked to repeat the same written examination performed at the end of the preclinical course in the sixth semester. The examinations consisted of 30 multiple-choice questions covering factual and procedural knowledge. The percentage of correctly answered questions per exam and differences in correct answers between the original examination and the re-examination (per question) were analyzed. Students were also asked to self-rate their percentage of correctly answered questions and their knowledge in various disciplines of operative dentistry at the times of the original examination and the re-examination. After exclusions, data were analyzed for 129 students, for a participation rate of 82%. For the seventh- and tenth-semester students, the results on the original examination and the re-examination were not significantly different, while the eighth- and ninth-semester students performed significantly better on the original examination than the re-examination. In all semesters, procedural knowledge remained stable between the original examination and the re-examination, while factual knowledge decreased slightly. Their performance on the original examination was underestimated by the eighth- and ninth-semester students. All the students underestimated their performance on the re-examination. Students mostly rated their knowledge level significantly higher on the original examination than on the re-examination. Overall, this study found that factual and procedural knowledge gained in a preclinical course in operative dentistry was not increased during the clinical dental curriculum."],["dc.identifier.doi","10.21815/jde.018.092"],["dc.identifier.pmid","30173190"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/57560"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/65678"],["dc.language.iso","en"],["dc.notes.status","final"],["dc.relation.eissn","1930-7837"],["dc.relation.issn","0022-0337"],["dc.relation.orgunit","Poliklinik für Präventive Zahnmedizin, Parodontologie und Kariologie"],["dc.subject.gro","assessment"],["dc.subject.gro","dental education"],["dc.subject.gro","operative dentistry"],["dc.subject.gro","self-assessment"],["dc.title","Dental Students' Factual and Procedural Knowledge Retention in Operative Dentistry in a Clinical Dental Curriculum"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dspace.entity.type","Publication"]]