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Prevalence of technical errors and periapical lesions in a sample of endodontically treated teeth: a CBCT analysis



The aims of this study are to identify the most frequent technical errors in endodontically treated teeth and to determine which root canals were most often associated with those errors, as well as to relate endodontic technical errors and the presence of coronal restorations with periapical status by means of cone-beam computed tomography images.


Six hundred eighteen endodontically treated teeth (1146 root canals) were evaluated for the quality of their endodontic treatment and for the presence of coronal restorations and periapical lesions. Each root canal was classified according to dental groups, and the endodontic technical errors were recorded. Chi-square’s test and descriptive analyses were performed.


Six hundred eighty root canals (59.3%) had periapical lesions. Maxillary molars and anterior teeth showed higher prevalence of periapical lesions (p < 0.05). Endodontic treatment quality and coronal restoration were associated with periapical status (p < 0.05). Underfilling was the most frequent technical error in all root canals, except for the second mesiobuccal root canal of maxillary molars and the distobuccal root canal of mandibular molars, which were non-filled in 78.4 and 30% of the cases, respectively.


There is a high prevalence of apical radiolucencies, which increased in the presence of poor coronal restorations, endodontic technical errors, and when both conditions were concomitant. Underfilling was the most frequent technical error, followed by non-homogeneous and non-filled canals.

Clinical relevance

Evaluation of endodontic treatment quality that considers every single root canal aims on warning dental practitioners of the prevalence of technical errors that could be avoided with careful treatment planning and execution.
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V-Posil Mono-Fast Impression Material From Voco

Extending the Line of V-Posil Precision VPS Impression Materials
After the successful introduction of V-Posil tray and wash impression materials, VOCO is expanding its V-Posil line with a monophase viscosity in V-Posil Mono-Fast.
V-Posil Mono-Fast as with the rest of the V-Posil viscosities offer optimized timing that provides up to 2-minutes of adjustable working time as well as an abbreviated 2-minute thermo-activated set time.  Additionally, V-Posil provides exceptional tear strength and elastic recovery (99.6%) to ensure dimensional accuracy of the impression after its removal.  Lab Technicians will appreciate V-Posil’s unique post-set contact angle of less than SIX degrees (<6 a="" accurate="" better="" ensures="" fitting="" for="" hydrophilicity="" models="" more="" post-set="" providing="" restorations.="" span="" stone="" that="">
This VPS material is indicated for taking impressions over fixed/removable restorations and implants (i.e., transferring impression posts and bridge components), functional impressions, fabricating crown and bridgework or inlays, fabricating full or partial dentures, reline impressions, transferring root posts when fabricating posts and cores indirectly, multi-tray, simultaneous as well as the putty-wash technique.
Available in 50ml cartridge refills and in the 380ml automix Dynamic Dispenser cartridge. 
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Clinical oral dryness score: evaluation of a new screening method for oral dryness


pp 1–6 | Cite as


The purpose of this study was to explore the association of the clinical oral dryness score (CODS) with salivary flow rates, xerostomia inventory (XI), and bother index (BI). 147 patients were screened using CODS, which determined 10 features of oral dryness. Each feature contributed 1 point, and the total score varied from 0 to 10. Unstimulated (UWS), chewing-stimulated (CH-SWS) and acid-stimulated (A-SWS) whole salivary flows and the XI and BI were measured. Associations were explored with a bootstrapped Spearman rank correlation test (1000 × bootstrapping). Based on unstimulated salivary flow, 55 patients were classified as hyposalivators, 31 as low salivators, 48 as normosalivators and 13 as high salivators. Median CODS in the hyposalivation group was 5 (IQR 3–6) compared with 3 (IQR 2–5) in the low salivation group, 2 (IQR 1–4) in the normal salivation group and 2 (IQR 1–2.5) in the high salivation group. Significant associations between CODS and the other parameters were only found in the hyposalivation group between CODS and UWS (ρ(53) = − 0.513; p < 0.01), between CODS and CH-SWS (ρ(53) = − 0.453; p < 0.01), between CODS and A-SWS (ρ(53) = − 0.500; p < 0.01), CODS and XI (ρ(53) = 0.343; p < 0.001) and between CODS and BI (ρ(53) = 0.375; p = 0.01). In patients with hyposalivation, CODS is associated with unstimulated and stimulated salivary flow and XI and BI. CODS alone or a combination of CODS with a subjective measure, such as the XI or BI, could be recommended during routine clinical assessment to detect hyposalivation.
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3M and 3Shape Partner to Advance Digital Workflows for Orthodontics

ST. PAUL‚ Minn. – (Jan. 29, 2018) – 3M and 3Shape announced their intention to work together to advance the field of orthodontics through digital workflows supporting indirect bonding, clear aligners and other emerging digital orthodontic workflows.
“Our partnership with 3Shape puts our customers first and is designed with practitioners, their patients, and their businesses in mind. Our goal is to make it easier for Orthodontists to engage patients, provide effective treatments and run a profitable practice. The workflow will include our indirect bonding solutions, our customized lingual offering, and future new offerings in the digital orthodontic space,” said Jim Ingebrand, President and General Manager, 3M Oral Care Division.
For 3M’s and 3Shape’s joint customers, the cooperation will enable use of the 3Shape TRIOS scanner and 3Shape indirect bonding software with 3M’s IncognitoTM lingual appliance system, the ClarityTM ADVANCED brackets with APCTM Flash Free technology for indirect bonding procedures, as well as future orthodontic product offerings. These combined solutions will enable better outcome while improving productivity of the practice.
“3Shape believes that an open market with freedom of choice is in the best interest of doctors and patients. Partnering with 3M will help orthodontists provide better treatment for their patients using 3Shape’s award winning TRIOS scanner and digital workflow software with 3M’s treatment solutions in integrated workflows,” said Allan Hyldal, 3Shape Vice President, Orthodontics & Implantology.
Emerging technology is enabling new efficiencies and greater predictability in the practice of orthodontics. While technology is changing how orthodontics is practiced, the end goal remains the same —a beautiful smile and healthy teeth that will last a lifetime.
No two smiles are alike. To develop customized treatment plans for each patient’s unique clinical diagnosis, orthodontists need flexible, choice-based solutions that deliver the best outcomes for their patients.
About 3M
At 3M, we apply science in collaborative ways to improve lives daily. With $32 billion in sales, our 91,000 employees connect with customers all around the world. Learn more about 3M’s creative solutions to the world’s problems at or on Twitter @3M or @3MNews.
About 3Shape
3Shape is changing dentistry together with dental professionals across the world by developing innovations that provide superior dental care for patients. Our portfolio of 3D scanners and CAD/CAM software solutions for the dental industry includes the multiple award-winning 3Shape TRIOS intraoral scanner, the upcoming 3Shape X1 CBCT scanner, and market leading scanning and design software solutions for dental labs.

Two graduate students founded 3Shape in Denmark’s capital in the year 2000. Today, 3Shape has over 1,200 employees serving customers in over 100 countries from an ever- growing number of 3Shape offices around the world. 3Shape’s products and innovations continue to challenge traditional methods, enabling dental professionals to treat more patients more effectively.
APC, Clarity and Incognito are trade marks of 3M Company. TRIOS is a registered trademark of 3Shape.
© 3M 2017. All rights reserved. Used under license in Canada.
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The marginal fit of lithium disilicate crowns: Press vs. CAD/CAM

Braz. oral res. vol.32  São Paulo  2018  Epub Jan 22, 2018 

This study aimed to compare the vertical marginal gap of teeth restored with lithium disilicate crowns fabricated using CAD/CAM or by pressed ceramic approach. Twenty mandibular third molar teeth were collected after surgical extractions and prepared to receive full veneer crowns. Teeth were optically scanned and lithium disilicate blocks were used to fabricate crowns using CAD/CAM technique. Polyvinyl siloxane impressions of the prepared teeth were made and monolithic pressed lithium disilicate crowns were fabricated. The marginal gap was measured using optical microscope at 200× magnification (Keyence VHX-5000, Japan). Statistical analysis was performed using Wilcoxon test. The lithium disilicate pressed crowns had significantly smaller (p = 0.006) marginal gaps (38 ± 12 μm) than the lithium disilicate CAD/CAM crowns (45 ± 12 μm). This research indicates that lithium disilicate crowns fabricated with the press technique have measurably smaller marginal gaps compared with those fabricated with CAD/CAM technique within in vitro environments. The marginal gaps achieved by the crowns across all groups were within a clinically acceptable range.

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