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crack tooth

Shuang Wang, Yiran Xu, Zhengyan Shen, Lijun Wang, Feng Qiao, Xu Zhang, Minghua Li, Ligeng Wu
BACKGROUND: The aim of this study was to investigate the extent of the crack of a cracked tooth on an artificial simulation model with Periapical Radiography (PR) and cone beam computed tomography (CBCT) in vitro, providing the basis for early diagnosis and an appropriate treatment plan. METHODS: Forty-four teeth with different extents of artificial cracks, created by exposure to liquid nitrogen after hot water at 100°C, were collected. They were subjected to PR and CBCT...
2017: PloS One
Nils Löfgren, Christel Larsson, Nikos Mattheos, Martin Janda
OBJECTIVE: Technical complications such as veneer fractures are more common in implant-supported than tooth-supported restorations. The underlying causes have not been fully identified. The aim of this study was to evaluate whether misfit between the restoration and the implant may affect the risk of veneer fractures. MATERIALS AND METHODS: Twenty standardized five-unit implant-supported metal-ceramic fixed dental prostheses (FDP)s were manufactured and fixed in acrylic blocks...
December 19, 2016: Clinical Oral Implants Research
Peter Panfilov, Anna Kabanova, Jinming Guo, Zaoli Zhang
This is the first transmission electron microscopic study of teenage crown dentin on the nanometer scale. Samples for TEM were prepared by mechanical thinning and chemical polishing that allowed obtaining the electron transparent foils. It was firstly shown that human dentin possesses the layered morphology: the layers are oriented normally to the main axis of a tooth and have the thickness of ~50nm. HA inorganic phase of teenage crown dentin is in the amorphous state. The cellular structure, which was formed from collagen fibers (diameter is ~5nm), are observed near DEJ region in teenage dentin, whereas bioorganic phase of teenage crown dentin near the pulp camera does not contain the collagen fibers...
February 1, 2017: Materials Science & Engineering. C, Materials for Biological Applications
Vincent R Sherman, Nicholas A Yaraghi, David Kisailus, Marc A Meyers
Atractosteus spatula has been described as a living fossil (having existed for 100 Myr), retaining morphological characteristics of early ancestors such as the ability to breathe air and survive above water for hours. Its highly effective armour consists of ganoid scales. We analyse the protective function of the scales and identify key features which lead to their resistance to failure. Microstructural features include: a twisted cross-plied mineral arrangement that inhibits crack propagation in the external ganoine layer, mineral crystals that deflect cracks in the bony region in order to activate the strength of mineralized collagen fibrils, and saw-tooth ridges along the interface between the two scale layers which direct cracks away from the intrinsically weak interface...
December 2016: Journal of the Royal Society, Interface
Maddalena Manfredi, Lara Figini, Massimo Gagliani, Giovanni Lodi
BACKGROUND: Root canal treatment (RoCT), or endodontic treatment, is a common procedure in dentistry. The main indications for RoCT are irreversible pulpitis and necrosis of the dental pulp caused by carious processes, tooth cracks or chips, or dental trauma. Successful RoCT is characterised by an absence of symptoms (i.e. pain) and clinical signs (i.e. swelling and sinus tract) in teeth without radiographic evidence of periodontal involvement (i.e. normal periodontal ligament). The success of RoCT depends on a number of variables related to the preoperative condition of the tooth, as well as the endodontic procedures...
1, 2016: Cochrane Database of Systematic Reviews
M S Segarra, Y Shimada, A Sadr, Y Sumi, J Tagami
The aim of this study was to nondestructively analyze enamel crack behavior on different areas of teeth using 3D swept source-optical coherence tomography (SS-OCT). Ten freshly extracted human teeth of each type on each arch (n = 80 teeth) were inspected for enamel crack patterns on functional, contact and nonfunctional, or noncontact areas using 3D SS-OCT. The predominant crack pattern for each location on each specimen was noted and analyzed. The OCT observations were validated by direct observations of sectioned specimens under confocal laser scanning microscopy (CLSM)...
November 21, 2016: Journal of Dental Research
X P Luo, Y Yuan, Y J Shi, D D Qian
Objective: To evaluate the clinic performance of high strength glass ceramic crowns for the painful cracked teeth during a 10-year observation period. Methods: Forty-two posterior teeth from 36 patients were diagnosed as having a crack, biting painful and sensitivity to cold were selected in the Department of Prosthodontic, Institute and Hospital of Stomatology, Nanjing University Medical School. The lost-wax hot pressed glass ceramic crowns were bonded on the minimally invasive prepared teeth by modern adhesive technology...
October 9, 2016: Zhonghua Kou Qiang Yi Xue za Zhi, Zhonghua Kouqiang Yixue Zazhi, Chinese Journal of Stomatology
Roza Haghgoo, Motahare Ahmadvand, Sareh Moshaverinia
INTRODUCTION: NovaMin is a synthetic mineral compound composed of calcium, sodium, phosphorus, and silica. It releases crystalline hydroxyl-carbonate apatite (HCA), which structurally resembles the minerals naturally found in the teeth. Nano-hydroxyapatite (NHA) is a biocompatible compound with high affinity for tooth enamel. NHA particles morphologically resemble dental enamel apatite crystals. Considering the efficacy of remineralizing agents and the importance of conservative preventive measures, this study aimed to compare the remin-eralizing effects of NovaMin and NHA on caries-like lesions in primary teeth...
August 1, 2016: Journal of Contemporary Dental Practice
Mini Saluja, Harpreet Singh Grover, Pankaj Choudhary
INTRODUCTION: Dentinal hypersensitivity is one of the most common problem, encountered in dental practice but has least predictable treatment outcome. The advent of lasers in dentistry has provided an additional therapeutic option for treating dentinal hypersensitivity. Although various lasers have been tried over a period of time to treat dentinal hypersensitivity, but still the doubt persist as to which laser leads to maximum dentinal tubular occlusion and is most suitable with minimal hazardous effects...
July 2016: Journal of Clinical and Diagnostic Research: JCDR
Manju Raj Kumari, Manjunath Mysore Krishnaswamy
INTRODUCTION: Success of any endodontic treatment depends on strict adherence to 'endodontic triad'. Preparation of root canal system is recognized as being one of the most important stages in root canal treatment. At times, we inevitably end up damaging root dentin which becomes a Gateway for infections like perforation, zipping, dentinal cracks and minute intricate fractures or even vertical root fractures, thereby resulting in failure of treatment. Several factors may be responsible for the formation of dentinal cracks like high concentration of sodium hypochlorite, compaction methods and various canal shaping methods...
July 2016: Journal of Clinical and Diagnostic Research: JCDR
Sugunakar Raju Godishala Swamy, Shyam Prasad Reddy Dorankula, Keerthi Muddana
INTRODUCTION: In forensic context precise knowledge on physical and histological changes of teeth subjected to high temperatures is of great importance. Preserving fragile incinerated teeth for physical, histological and ultra structural examinations is essential in fire investigations involving the origin of fire, its cause as well as the identification of victims which relies on a thorough understanding of the structural changes in dental tissues subjected to heat. AIM: The study was conducted to evaluate the physical and ultrastructural changes seen in freshly extracted teeth when subjected to gradual heating at different temperatures using Scanning Electron Microscope (SEM)...
July 2016: Journal of Clinical and Diagnostic Research: JCDR
Hsuan-Wen Wang, Yen-Hsiang Chang, Chun-Li Lin
This study evaluates the fracture resistance in an endodontically treated tooth using circular fiber-reinforced composite (FRC) and innovated anatomical short glass fiber reinforced (SGFR) posts under fatigue testing, monitored using the acoustic emission (AE) technique. An anatomical SGFR fiber post with an oval shape and slot/notch design was manufactured using an injection-molding machine. Crown/core maxillary second premolar restorations were executed using the anatomical SGFR and commercial cylindrical fiber posts under fatigue test to understand the mechanical resistances...
January 2017: Journal of the Mechanical Behavior of Biomedical Materials
Paul J Constantino, Mark B Bush, Amir Barani, Brian R Lawn
A hallmark of mammalian evolution is a progressive complexity in postcanine tooth morphology. However, the driving force for this complexity remains unclear: whether to expand the versatility in diet source, or to bolster tooth structural integrity. In this study, we take a quantitative approach to this question by examining the roles of number, position and height of multiple cusps in determining sustainable bite forces. Our approach is to use an extended finite-element methodology with due provision for step-by-step growth of an embedded crack to determine how fracture progresses with increasing occlusal load...
August 2016: Journal of the Royal Society, Interface
Z Y Weng, Z Q Liu, R O Ritchie, D Jiao, D S Li, H L Wu, L H Deng, Z F Zhang
The giant panda׳s teeth possess remarkable load-bearing capacity and damage resistance for masticating bamboos. In this study, the hierarchical structure and mechanical behavior of the giant panda׳s tooth enamel were investigated under indentation. The effects of loading orientation and location on mechanical properties of the enamel were clarified and the evolution of damage in the enamel under increasing load evaluated. The nature of the damage, both at and beneath the indentation surfaces, and the underlying toughening mechanisms were explored...
December 2016: Journal of the Mechanical Behavior of Biomedical Materials
Michael S McCracken, David R Louis, Mark S Litaker, Helena M Minyé, Rahma Mungia, Valeria V Gordan, Don G Marshall, Gregg H Gilbert
BACKGROUND: The objectives of this study were to quantify practitioner variation in likelihood to recommend a crown and test whether certain dentist, practice, and clinical factors are associated significantly with this likelihood. METHODS: Dentists in The National Dental Practice-Based Research Network completed a questionnaire about indications for single-unit crowns. In 4 clinical scenarios, practitioners ranked their likelihood of recommending a single-unit crown...
November 2016: Journal of the American Dental Association
Fauzia Ashraf, Pushpa Shankarappa, Abhinav Misra, Asheesh Sawhney, Nandamuri Sridevi, Anu Singh
Introduction. The aim of the present study was to evaluate the dentinal cracks after root canal preparation with rotary files: Gates Glidden, ProTaper Universal, ProTaper Next, and HyFlex CM at different instrumentation lengths. Methodology. Sixty-five mandibular premolars were mounted in the acrylic tube with simulated periodontal ligaments and the apex was exposed. The root canals were instrumented with different rotary files, namely, ProTaper Universal, ProTaper Next, and HyFlex CM, to the major apical foramen (AF), short AF, and beyond AF...
2016: Scientifica
Gianfranco Politano, Andrea Fabianelli, Federica Papacchini, Antonio Cerutti
Restorative procedures are accompanied by a reduction of tooth stability, a decrease of fracture resistance, and an increase in deflection of weakened cusps. The choice between a direct or an indirect restorative technique, mainly in posterior areas, is a challenge, and involves biomechanical, anatomical, functional, esthetic, and financial considerations. In this article, the pros and cons of direct restorations are examined, as well as an analysis of indirect restorations and an overview of dental ceramics...
December 0: International Journal of Esthetic Dentistry
Djaudat Idiyatullin, Michael Garwood, Laurence Gaalaas, Donald R Nixdorf
OBJECTIVES: To evaluate the limit of tooth crack width visualization by two MRI pulse sequences in comparison with CBCT. METHODS: Two extracted human teeth with known crack locations and dimensions, as determined by reference standard microCT, were selected for experimental imaging. Crack location/dimension and the presence of common dental restorative materials such as amalgam were typical of that found clinically. Experimental imaging consisted of conventional CBCT scans and MRI scans with two pulse sequences including Sweep Imaging with Fourier Transformation (SWIFT) and gradient echo (GRE)...
2016: Dento Maxillo Facial Radiology
Raquel P Antoniazzi, Fabricio B Zanatta, Cassiano K Rösing, Carlos Alberto Feldens
BACKGROUND: Crack cocaine can alter functions related to the immune system and exert a negative influence on progression and severity of periodontitis. The aim of this study is to compare periodontal status between crack cocaine users and crack cocaine non-users and investigate the association between crack cocaine and periodontitis after adjustments for confounding variables. METHODS: This cross-sectional study evaluated 106 individuals exposed to crack cocaine and 106 never exposed, matched for age, sex, and tobacco use...
December 2016: Journal of Periodontology
Niklas Rommel, Nils H Rohleder, Steffen Koerdt, Stefan Wagenpfeil, Roland Härtel-Petri, Klaus-Dietrich Wolff, Marco R Kesting
BACKGROUND: Methamphetamine, a highly addictive sympathomimetic stimulant, is currently widely abused worldwide and has been associated with devastating effects on oral health, resulting in the term "meth mouth". However, "meth mouth" pathology is primarily based on case reports with a lack of systematic clinical evaluation. Therefore, we have conducted a systematic study to investigate (1) the pharmacological impact of methamphetamine on oral health with regard to saliva function, including the parameters saliva flow rate and total saliva production (ml/5 min) and the buffering capacity of saliva; (2) the contribution of the symptoms of bruxism and muscle trismus to potential oral health damage...
2016: BMC Oral Health
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