TY - JOUR A1 - Ludwig, Julia A1 - Reymus, Marcel A1 - Winkler, Alexander A1 - Soliman, Sebastian A1 - Krug, Ralf A1 - Krastl, Gabriel T1 - Root maturation of an immature dens invaginatus despite unsuccessful revitalization procedure: a case report and recommendations for educational purposes JF - Dentistry Journal N2 - Background: The clinical management of teeth with complex dens invaginatus (DI) malformations and apical periodontitis may be challenging due to the lack of routine. The aim of this case report is to describe the endodontic treatment of an immature tooth with DI and to discuss strategies for preclinical training for teeth with such malformations. Case report: A 9-year-old male presented with an immature maxillary incisor with DI (Oehlers Type II) and apical periodontitis which was diagnosed by cone beam computed tomography (CBCT). Revitalization was initially attempted but then abandoned after failure to generate a stable blood clot. Nevertheless, considerable increase in both root length and thickness could be detected after medication with calcium hydroxide followed by root canal filling with MTA as an apical plug. Conclusions: The endodontic management of teeth with DI requires thorough treatment planning. In immature teeth, under certain conditions, root maturation may occur even with conventional apexification procedures. From an educational perspective, different strategies including CBCT and 3D-printed transparent tooth models for visualization of the complex internal morphology and redesigned 3D-printed replica with various degrees of difficulty for endodontic training, can be used to overcome the challenges associated with endodontic treatment of such teeth. KW - dens invaginatus KW - immature tooth KW - revitalization KW - apexification KW - 3D printing KW - dental education KW - replica Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-304108 SN - 2304-6767 VL - 11 IS - 2 ER - TY - JOUR A1 - Kolling, Markus A1 - Backhaus, Joy A1 - Hofmann, Norbert A1 - Keß, Stefan A1 - Krastl, Gabriel A1 - Soliman, Sebastian A1 - König, Sarah T1 - Students’ perception of three-dimensionally printed teeth in endodontic training JF - European Journal of Dental Education N2 - Introduction In endodontic education, there is a need for thorough training prior to students embarking on clinical treatment. The aim of this study was to use three-dimensional printing technology to create a new model and to compare its suitability for training purposes with resin blocks and extracted teeth. Materials and Methods Multi-jet-modelling (MJM) produced the 3D model replicating a common difficulty in root-canal morphology. An evaluation study comprising 88 students was run in the sixth semester (summer 2018 and winter 2018/2019). A new questionnaire assessed students’ perception of training models and educational environment. Welch's t-test analysed significant differences. Results The most pronounced differences between models were noted when rating material hardness, radiopacity, root-canal configuration and suitability for practising. Students estimated their learning outcome as greater with 3D-printed teeth compared to resin blocks. Three-dimensionally printed teeth received significantly lower ratings with regard to enthusiasm, the learning of fine motor skills and spatial awareness, when compared to human teeth (p ≤ .001). However, 3D-printed teeth were appreciated for additional benefits, such as their cleanliness, availability and standardisation of training opportunities with complex root-canal configurations. Conclusion Students preferred extracted human teeth to 3D-printed teeth with respect to their physical characteristics and training experience. However, educational advantages may compensate for the shortcomings. The new questionnaire proved both adequate and accurate to assess the models and educational environment in endodontic training. The new 3D-printed teeth enhanced the learning opportunities. KW - 3D-printed tooth KW - three-dimensional printing KW - teaching materials KW - root-canal treatment KW - endodontics KW - dental education Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-318676 VL - 26 IS - 4 SP - 653 EP - 661 ER - TY - JOUR A1 - Hahn, Britta A1 - Haubitz, Imme A1 - Krug, Ralf A1 - Krastl, Gabriel A1 - Soliman, Sebastian T1 - Influence of matrix type on marginal gap formation of deep class II bulk-fill composite restorations JF - International Journal of Environmental Research and Public Health N2 - Background: To test the hypothesis that transparent matrices result in more continuous margins of bulk-fill composite (BFC) restorations than metal matrices. Methods: Forty standardized MOD cavities in human molars with cervical margins in enamel and dentin were created and randomly assigned to four restorative treatment protocols: conventional nanohybrid composite (NANO) restoration (Tetric EvoCeram, Ivoclar Vivadent, Schaan, Liechtenstein) with a metal matrix (NANO-METAL) versus transparent matrix (NANO-TRANS), and bulk-fill composite restoration (Tetric EvoCeram Bulk Fill, Ivoclar Vivadent, Schaan, Liechtenstein) with a metal matrix (BFC-METAL) versus transparent matrix (BFC-TRANS). After artificial aging (2500 thermal cycles), marginal quality was evaluated by scanning electron microscopy using the replica technique. Statistical analyses were performed using the Mann–Whitney U-test and Wilcoxon test. The level of significance was p < 0.05. Results: Metal matrices yielded significantly (p = 0.0011) more continuous margins (46.211%) than transparent matrices (27.073%). Differences in continuous margins between NANO (34.482%) and BFC (38.802%) were not significant (p = 0.56). Matrix type did not influence marginal gap formation in BFC (p = 0.27) but did in NANO restorations (p = 0.001). Conclusion: Metal matrices positively influence the marginal quality of class II composite restorations, especially in deep cavity areas. The bulk-fill composite seems to be less sensitive to the influence of factors such as light polymerization and matrix type. KW - transparent matrix KW - metal matrix KW - bulk-fill technique KW - centripetal technique KW - marginal gap formation KW - class II restoration KW - SEM Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-270712 SN - 1660-4601 VL - 19 IS - 9 ER - TY - JOUR A1 - Magni, Eva A1 - Leontiev, Wadim A1 - Soliman, Sebastian A1 - Dettwiler, Christian A1 - Klein, Christian A1 - Krastl, Gabriel A1 - Weiger, Roland A1 - Connert, Thomas T1 - Accuracy of the fluorescence-aided identification technique (FIT) for detecting residual composite remnants after trauma splint removal — a laboratory study JF - Applied Sciences N2 - Distinguishing composite remnants from tooth structure after trauma splint removal can be challenging. This study aimed to compare the Fluorescence-aided Identification Technique (FIT) with conventional light illumination (CONV) in terms of accuracy and time required for the detection of composite remnants after trauma splint removal. Ten bovine tooth models containing anterior teeth from 12 to 22 with composite remnants after trauma splint removal were used. These models were examined by 10 students and 10 general dentists. Each examiner assessed the 10 models using CONV or FIT three times with an interval of 2 weeks each using a prototype fluorescence-inducing headlamp with a spectral bandwidth of (405 ± 7) nm for FIT and a dental unit lamp for CONV. The examiners charted the location of identified composite remnants, and the procedure time needed for each method was recorded. Statistical analysis was performed with R 3.2.2 software with a significance level of α = 5%. FIT was more accurate and less time-consuming than CONV (p < 0.001). There were no significant differences between dentists and students concerning accuracy (CONV: p = 0.26; FIT: p = 0.73). Students performed FIT significantly faster than the dentists (p < 0.001). FIT is a quick and reliable method of identifying composite remnants after trauma splint removal. KW - composite detection KW - fluorescence-aided identification technique KW - titanium trauma splint (TTS) removal Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-290252 SN - 2076-3417 VL - 12 IS - 19 ER - TY - JOUR A1 - Krastl, G. A1 - Weiger, R. A1 - Filippi, A. A1 - van Wees, H. A1 - Ebeleseder, K. A1 - Ree, M. A1 - Connert, T. A1 - Widbiller, M. A1 - Tjäderhane, L. A1 - Dummer, P. M. H. A1 - Galler, K. T1 - Endodontic management of traumatized permanent teeth: a comprehensive review JF - International Endodontic Journal N2 - The pulp plays a key role in the treatment of traumatic dental injuries (TDIs) and is strongly associated with the outcome, particularly in severe cases. A correct pulp diagnosis is essential as it forms the basis for developing the appropriate management strategy. However, many TDIs are complex, and their treatment requires a profound knowledge of the physiological and pathological responses of the affected tissues. This comprehensive review will look at the dentine–pulp complex and its interaction with the surrounding tissues following TDIs. The literature up to 2020 was reviewed based on several searches on PubMed and the Cochrane Library using relevant terms. In addition to the recently revised guidelines of the International Association of Dental Traumatology, this article aims to provide background information with a focus on endodontic aspects and to gather evidence on which a clinician can make decisions on the choice of the appropriate endodontic approach for traumatized permanent teeth. KW - avulsion KW - diagnosis KW - tooth injuries KW - tooth fracture KW - endodontic management KW - dental trauma Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-259412 VL - 54 IS - 8 ER - TY - JOUR A1 - Reichardt, Elisabeth A1 - Krug, Ralf A1 - Bornstein, Michael M. A1 - Tomasch, Jürgen A1 - Verna, Carlalberta A1 - Krastl, Gabriel T1 - Orthodontic forced eruption of permanent anterior teeth with subgingival fractures: a systematic review JF - International Journal of Environmental Research and Public Health N2 - (1) Background: To assess orthodontic forced eruption (OFE) as a pre-restorative procedure for non-restorable permanent teeth with subgingival dental hard tissue defects after dental trauma. (2) Methods: A systematic electronic search of three databases, namely, MEDLINE, Cochrane Library, and EMBASE, revealed a total of 2757 eligible publications. Randomized controlled clinical trials (RCT), retro- and prospective clinical studies, or case series (with a minimum of three patients) were reviewed. (3) Results: Thirteen full-text papers were included: one RCT, one prospective clinical trial, two retrospective cohort studies, and nine case series. Within case series, statistical significance between age and cause of fracture (p < 0.03) was determined. The mean extrusion rate of OFE was 1.5 mm a week within a four to six weeks treatment period followed by retention. Three OFE protocols for maxillary single teeth are available: 1. OFE without migration of gingiva and alveolar bone, 2. OFE with gingival migration and slight alveolar bone migration, and 3. OFE with migration of both gingiva and alveolar bone. (4) Conclusions: The current state of the evidence suggests that OFE is a feasible pre-treatment option for non-restorable permanent teeth. OFE can promote the migration of tooth surrounding hard and soft tissues in the esthetic zone. Root resorption does not seem to be a relevant side effect of OFE. KW - orthodontic forced eruption KW - crown-root fracture KW - subgingival defects KW - dental hard tissue defects KW - dental trauma KW - root resorption Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-250192 SN - 1660-4601 VL - 18 IS - 23 ER - TY - JOUR A1 - Wolf-Brandstetter, C A1 - Beutner, R A1 - Hess, R A1 - Bierbaum, S A1 - Wagner, K A1 - Scharnweber, D A1 - Gbureck, U A1 - Moseke, C T1 - Multifunctional calcium phosphate based coatings on titanium implants with integrated trace elements JF - Biomedical Materials N2 - For decades, the main focus of titanium implants developed to restore bone functionality was on improved osseointegration. Additional antimicrobial properties have now become desirable, due to the risk that rising antibiotic resistance poses for implant-associated infections. To this end, the trace elements of copper and zinc were integrated into calcium phosphate based coatings by electrochemically assisted deposition. In addition to their antimicrobial activity, zinc is reported to attract bone progenitor cells through chemotaxis and thus increase osteogenic differentiation, and copper to stimulate angiogenesis. Quantities of up to 68.9 ± 0.1 μg cm\(^{-2}\) of copper and 56.6 ± 0.4 μg cm\(^{-2}\) of zinc were deposited; co-deposition of both ions did not influence the amount of zinc but slightly increased the amount of copper in the coatings. The release of deposited copper and zinc species was negligible in serum-free simulated body fluid. In protein-containing solutions, a burst release of up to 10 μg ml\(^{-1}\) was observed for copper, while zinc was released continuously for up to 14 days. The presence of zinc was beneficial for adhesion and growth of human mesenchymal stromal cells in a concentration-dependent manner, but cytotoxic effects were already visible for coatings with an intermediate copper content. However, co-deposited zinc could somewhat alleviate the adverse effects of copper. Antimicrobial tests with E. coli revealed a decrease in adherent bacteria on brushite without copper or zinc of 60%, but if the coating contained both ions there was almost no bacterial adhesion after 12 h. Coatings with high zinc content and intermediate copper content had the overall best multifunctional properties. KW - coating KW - titanium KW - implant KW - pro-angiogenic KW - osteogenic KW - antimicrobial Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-254085 VL - 15 IS - 2 ER - TY - JOUR A1 - Krug, Ralf A1 - Volland, Julian A1 - Reich, Sebastian A1 - Soliman, Sebastian A1 - Connert, Thomas A1 - Krastl, Gabriel T1 - Guided endodontic treatment of multiple teeth with dentin dysplasia: a case report JF - Head & Face Medicine N2 - Background To report the outcome of guided endodontic treatment (GET) of a case of dentin dysplasia with pulp canal calcification (PCC) and apical periodontitis based on the use of a 3D-printed template designed by merging cone-beam computed tomography (CBCT) and surface scan data. Case presentation A 12-year old female with radicular dentin dysplasia type I (DD-1) presented for endodontic treatment. Radiography revealed PCC in all teeth and apical radiolucency in seven teeth (12, 15, 26, 31, 32, 36 and 46). Tooth 36 had the most acute symptoms and was thus treated first by conventional access cavity preparation and root canal detection. Despite meticulous technique, the distal and mesiolingual canals were perforated. The perforations were immediately repaired with mineral trioxide aggregate, and the decision was made to switch to guided endodontic treatment for the remaining 6 teeth. CBCT and intraoral surface scans were acquired and matched using coDiagnostix planning software (Dental Wings Inc.), the respective drill positions for root canal location were determined, and templates were virtually designed and 3D-printed. The template was positioned on the respective tooth, and a customized drill was used to penetrate the calcified part of the root canal and perform minimally invasive access cavity preparation up to the apical region. All root canals were rapidly and successfully located with the templates. At 1-year follow-up, clear signs of apical healing were present in all treated teeth. Conclusions In patients with dentin dysplasia, conventional endodontic therapy is challenging. GET considerably facilitates the root canal treatment of teeth affected by dentin dysplasia. KW - guided endodontics KW - pulp canal calcification KW - dentin dysplasia KW - root canal treatment KW - template KW - access caity preparation KW - beam computed tomography KW - canal calcification KW - permanent KW - obliteration Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-230271 VL - 16 ER - TY - JOUR A1 - Richter, Gesa M. A1 - Kruppa, Jochen A1 - Munz, Matthias A1 - Wiehe, Ricarda A1 - Häsler, Robert A1 - Franke, Andre A1 - Martins, Orlando A1 - Jockel-Schneider, Yvonne A1 - Bruckmann, Corinna A1 - Dommisch, Henrik A1 - Schaefer, Arne S. T1 - A combined epigenome- and transcriptome-wide association study of the oral masticatory mucosa assigns CYP1B1 a central role for epithelial health in smokers JF - Clinical Epigenetics N2 - Background The oral mucosa has an important role in maintaining barrier integrity at the gateway to the gastrointestinal and respiratory tracts. Smoking is a strong environmental risk factor for the common oral inflammatory disease periodontitis and oral cancer. Cigarette smoke affects gene methylation and expression in various tissues. This is the first epigenome-wide association study (EWAS) that aimed to identify biologically active methylation marks of the oral masticatory mucosa that are associated with smoking. Results Ex vivo biopsies of 18 current smokers and 21 never smokers were analysed with the Infinium Methylation EPICBeadChip and combined with whole transcriptome RNA sequencing (RNA-Seq; 16 mio reads per sample) of the same samples. We analysed the associations of CpG methylation values with cigarette smoking and smoke pack year (SPY) levels in an analysis of covariance (ANCOVA). Nine CpGs were significantly associated with smoking status, with three CpGs mapping to the genetic region of CYP1B1 (cytochrome P450 family 1 subfamily B member 1;best p=5.5x10(-8)) and two mapping to AHRR (aryl-hydrocarbon receptor repressor; best p=5.9x10(-9)). In the SPY analysis, 61 CpG sites at 52 loci showed significant associations of the quantity of smoking with changes in methylation values. Here, the most significant association located to the gene CYP1B1, with p=4.0x10(-10). RNA-Seq data showed significantly increased expression of CYP1B1 in smokers compared to non-smokers (p=2.2x10(-14)), together with 13 significantly upregulated transcripts. Six transcripts were significantly downregulated. No differential expression was observed for AHRR. In vitro studies with gingival fibroblasts showed that cigarette smoke extract directly upregulated the expression of CYP1B1. Conclusion This study validated the established role of CYP1B1 and AHRR in xenobiotic metabolism of tobacco smoke and highlights the importance of epigenetic regulation for these genes. For the first time, we give evidence of this role for the oral masticatory mucosa. KW - EWAS KW - Methylation KW - Expression KW - Masticatory mucosa KW - CYP1B1 KW - AHRR KW - Cytochrome P 450 pathway KW - OSCC KW - Smoking Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-226175 VL - 11 ER - TY - JOUR A1 - Harks, Inga A1 - Jockel-Schneider, Yvonne A1 - Schlagenhauf, Ulrich A1 - May, Theodor W. A1 - Gravemeier, Martina A1 - Prior, Karola A1 - Petersilka, Gregor A1 - Ehmke, Gregor T1 - Impact of the Daily Use of a Microcrystal Hydroxyapatite Dentifrice on De Novo Plaque Formation and Clinical/Microbiological Parameters of Periodontal Health. A Randomized Trial JF - PLoS ONE N2 - Aim This 12-week prospective, randomized, double-blind, two-center trial evaluated the impact of a microcrystalline zinc hydroxyapatite (mHA) dentifrice on plaque formation rate (PFR) in chronic periodontitis patients. We hypothesized that mHA precipitates cause delayed plaque development when compared to a fluoridated control (AmF/SnF\(_{2}\)), and therefore would improve periodontal health. Material & Methods At baseline and after 4 and 12 weeks, PFR and other clinical and microbiological parameters were recorded. Seventy periodontitis patients received a mHA or AmF/SnF\(_{2}\) dentifrice as daily oral care without hygiene instructions. Four weeks after baseline, participants received full mouth debridement and continued using the dentifrices for another 8 weeks. Results Primary outcome PFR did not change statistically significantly from baseline to weeks 4 and 12, neither in mHA (n = 33; 51.7±17.2% vs. 48.5±16.65% vs. 48.4±19.9%) nor in AmF/SnF2-group (n = 34; 52.3±17.5% vs. 52.5±21.3% vs. 46.1±21.8%). Secondary clinical parameters such as plaque control record, gingival index, bleeding on probing, and pocket probing depth improved, but between-group differences were not statistically significant. Microbiological analyses showed similar slight decreases in colony-forming units in both groups. Conclusion In patients with mild-to-moderate periodontitis, periodontal therapy and use of a mHA-or AmF/SnF\(_{2}\) dentifrice without instructions induced comparable improvements in periodontal health but did not significantly reduce the PFR. KW - microcrystalline zinc hydroxyapatiteimpact KW - plaque formation KW - periodontal health Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-166853 VL - 11 IS - 7 ER -