Publications by authors named "Ralf Krug"

Objectives: To assess the long-term clinical performance of ceramic in-/onlays (CIOs) and cast gold partial crowns (CGPCs) in posterior teeth in terms of success, survival, complications (biological, technical) and quality.

Material And Methods: In a retrospective study, a total of 325 patients were recorded after up to 24.8 years (mean 13.

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Objective: To evaluate the clinical outcome of root canal treatment by obturation technique, root canal filling quality, and tooth- and patient-related variables.

Methods: This clinical study investigated the endodontic outcome of 114 teeth treated between the years 2009 and 2012. Three different obturation methods were used: (1) adhesive obturation using the continuous wave of condensation technique with Resilon (CWR), (2) matching-taper single-cone technique with gutta-percha and AH Plus (SCGP), and (3) matching-taper single-cone technique with gutta-percha and GuttaFlow (SCGF).

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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).

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Objectives: Many treatment options accepted for unsalvageable traumatized teeth in adults would seem contraindicated in children and adolescents. Instead, growing patients need interim restorative measures, thus extensively preserving their local bone and soft tissue structures and, ideally, preparing the involved site for later definitive restoration while they transform to skeletal maturity. This narrative topic review addresses the interim management in case of very deep intra-extra-alveolar fractures, extensive infection-related root resorption, tooth ankylosis, and anterior tooth loss in growing patients, and seeks to empower the clinician to select the appropriate treatment approach.

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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.

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(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.

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Objectives: To evaluate the influence of filler geometry and viscosity of luting composites on marginal adhesive gap width (MGW) and occlusal surface height (OSH) of all-ceramic partial crowns.

Methods: Forty-eight all-ceramic partial crowns (Celtra Duo, Dentsply) were created and divided into six groups (n = 8). Restorations were bonded using universal adhesive (Prime & Bond Active, Dentsply) in combination with low-viscosity composites (LV) containing amorphous fillers (Calibra Ceram, Dentsply) (LV-AF), heterogeneous fillers (Tetric EvoFlow, Ivoclar Vivadent) (LV-HF) vs.

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Introduction: This study aimed to evaluate substance loss and the time required for access cavity preparation (ACP) using the conventional freehand method (CONV) versus a miniaturized dynamic navigation system of real-time guided endodontics (RTGE) in an in vitro model using 3-dimensional-printed teeth.

Methods: Nine human anterior maxillary teeth were selected and micro-computed tomographic scanned. Root canals were virtually reduced to 2 mm below the cementoenamel junction.

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Objectives: To assess tooth discoloration induced by different hydraulic calcium silicate-based cements (HCSCs), including effects of blood and placement method.

Materials And Methods: Eighty bovine teeth cut to a length of 18 mm (crown 8 mm, root 10 mm) were randomly assigned to 10 groups (n = 8), receiving orthograde apical plug treatment (APT). Apical plugs were 4 mm in length and made of ProRoot MTA (Dentsply), Medcem MTA (Medcem), TotalFill BC RRM Fast Set Putty (Brasseler), or Medcem Medical Portland Cement (Medcem) plus bismuth oxide (Bi2O3) with and without bovine blood.

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Introduction: This proof-of-principle study aimed to demonstrate that magnetic resonance imaging (MRI) is sufficiently accurate for the detection of root canals using guided endodontics.

Methods: One hundred extracted human teeth (anterior and premolar) were mounted onto 5 mandibular and 5 maxillary models, fitted with splints designed to accommodate a thin layer of aqueous gel for indirect imaging, and scanned by MRI. After MRI and intraoral scans were aligned using planning software, access cavities were planned virtually, and templates were manufactured with computer-aided design/computer-aided manufacturing, the access cavities were prepared.

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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).

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Aim: To compare the accuracy and effort of digital workflow for guided endodontic access (GEA) procedures using two different software applications in 3D-printed teeth modeled to simulate pulp canal obliteration (PCO) in vitro.

Materials And Methods: 32 3D-printed incisors with simulated PCO were fabricated and mounted, four each on maxillary and mandibular study arches. Cone beam computed tomography (CBCT) and 3D surface scans were matched and used to virtually plan and prepare GEA by one operator using two different methods: 1) CoDiagnostiX (CDX; Dental Wings) with 3D-printed templates, and 2) Sicat Endo (SE; Sicat) with subtractive CAD/CAM-manufactured templates.

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Background/aims: Adhesive fragment reattachment (AFR) is one treatment option for crown-root fractured teeth. However, there are no studies investigating the long-term outcome of this approach. The aim of this retrospective study was to evaluate the long-term outcome of AFR and periodontal health in crown-root fractured teeth by assessing complications and periodontal status.

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External cervical resorption (ECR) often renders a tooth nonrestorable, especially if it extends deeply within the dental hard tissue. Intentional replantation is sometimes performed as the last resort to save the tooth but may limit conventional forceps extraction because of the high risk of periodontal ligament cell damage or crown fracture.This case report describes the intentional replantation of an upper central incisor with extensive ECR using an axial, atraumatic extraction system to save the otherwise hopeless tooth.

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Surgical extrusion is a recognised treatment option for teeth that have insufficient coronal tooth structure remaining due to deep caries, resorption or traumatic injury. However, the technique has not been widely adopted, arguably because extraction of a severely compromised tooth may be difficult to achieve in a gentle and predictable way. In this paper, we present our novel approach to surgical extrusion and subsequent management of teeth using a vertical extraction system (Benex), which has become the method of choice in the authors' practice for many teeth that would otherwise be deemed unrestorable.

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Objective: To assess the impact of non-endodontic factors like periodontitis and chronic disease medication (CDM) mostly affecting elderly people's health on the outcome of non-surgical root canal treatment (NSRCT).

Background: An increasing number of elderly people with high prevalence of marginal periodontitis and CDM benefit from adequate endodontic therapy, if irreversible pulpitis or apical periodontitis occurs. Only few data exist about the relevance of those non-endodontic factors on healing of endodontic lesions in a population 60 years or more.

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Introduction: The aim of this in vitro study was to compare endodontic access cavities in teeth with calcified root canals prepared with the conventional technique and a guided endodontics approach regarding the detection of root canals, substance loss, and treatment duration.

Methods: Six identical sets of upper and lower jaw models were produced with 3-dimensional-printed incisors that had simulated calcified root canals. Splints for guided access preparations were fabricated based on 3-dimensional surface scans and cone-beam computed tomographic data sets.

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This study investigated the use of cone-beam computed tomography (CBCT) by endodontists in Germany and Switzerland. Sixty-eight German endodontic specialists (G-ES), 22 Swiss endodontic specialists (CH-ES) and 95 dentists with a German Master of Science in endodontics (MSc) were invited to participate. Data on the timing of diagnostic assessments, endodontic case difficulty and indications for CBCT use were collected by questionnaire.

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Ankylosis and external replacement resorption (ERR) are two typical biological responses to delayed replantation of avulsed teeth in cases where adequate root canal treatment is performed. The patient's growth stage affects the progression of root resorption and the long-term outcome of the affected teeth. This case report describes the long-term outcome of an 18.

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Statement Of Problem: Clinical studies evaluating the feasibility of a novel technique for the surgical extrusion of nonrestorable teeth with subgingival caries are lacking.

Purpose: The purpose of this clinical study was to investigate the success rate and incidence of biological and technical complications after tooth extrusion with an atraumatic extraction system (AES).

Material And Methods: Participants were recruited from 61 consecutive patients initially referred to a specialist oral surgery practice.

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The aminobisphosphonate zoledronic acid (ZA) is a bone seeking specific inhibitor of protein farnesylation and geranylgeranylation, which causes inhibition of osteoclast function and apoptosis. It is widely used as an osteoclast targeted antiresorptive treatment of metastatic bone disease, Paget's disease and osteoporosis. Mesenchymal stem cells (MSC) and osteoblast precursors can also be targets of bisphosphonates, but the clinical relevance of these effects is under debate.

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