Search results for "Incisor"
showing 10 items of 149 documents
Cross-sectional study of correlation between mandibular incisor crowding and third molars in young Brazilians
2012
Objectives: The aim of this study was to evaluate transversally the clinical correlation between lower incisor crowding and mandible third molar. Study Design: Three hundred healthy volunteers (134 male and 166 female), aged 20.4 (±2.4) years-old were submitted to a complete clinical examination and filled up a questionnaire about gender, age, total teeth number and presence or absence of superior and inferior third molar. After a recent panoramic radiography were evaluated. The multiple logistic regression showed that none of the studied factors influenced the mandibular incisor crowding. Results: The proportion of both molars present or both absent was higher than the other conditions (Ch…
Species-specific enamel differences in hardness and abrasion resistance between the permanent incisors of cattle (Bos primigenius taurus) and the eve…
2022
Hypselodont (ever-growing) teeth of lagomorphs or rodents have higher wear rates (of a magnitude of mm/week), with compensating growth rates, compared to the non-ever-growing teeth of ungulates (with a magnitude of mm/year). Whether this is due to a fundamental difference in enamel hardness has not been investigated so far. We prepared enamel samples (n = 120 per species) from incisors of cattle (Bos primigenius taurus) and nutria (Myocastor coypus, hypselodont incisors) taken at slaughterhouses, and submitted them to indentation hardness testing. Subsequently, samples were split into 4 groups per species (n = 24 per species and group) that were assessed for abrasion susceptibility by a sta…
Effects of endodontic treatment on apparent Young’s modulus of human teeth: in vitro study using speckle interferometry
2012
The introduction of new techniques for endodontic procedures requires the analysis of the biomechanical behavior of dental structures. Digital speckle shearing pattern interferometry (DSSPI) is a nondestructive optical measuring technique that allows one to directly quantify deformations in teeth that are subjected to stress. DSSPI technique was applied to measure small deformations caused by flexion in different types of teeth. The test was carried out both before and after endodontic treatment with the ProTaper method in order to evaluate the variation of dental elasticity, taking into the account the type of tooth and the endodontic treatment. The results obtained show that dental elasti…
Inclusion of the periodontal ligament in studies on the biomechanical behavior of fiber post-retained restorations: An in vitro study and three-dimen…
2016
Endodontically treated teeth are known to have reduced structural strength. Periodontal ligament may influence fracture resistance. The purpose of this study was to assess the influence of including the periodontal ligament in biomechanical studies about endodontically treated and restored teeth. Forty human maxillary central incisors were treated endodontically and randomly divided into four groups: non-crowned (with and without an artificial ligament) and crowned (with and without an artificial ligament) with glass-ceramic crowns. All groups received prefabricated glass-fiber posts and a composite resin core. Specimens were tested, under a flexural–compressive load, until failure occurre…
Efficacy of three methods for inserting calcium hydroxide-based paste in root canals
2017
BACKGROUND: To compare the quality of calcium hydroxide paste fillings performed by three different techniques. MATERIAL AND METHODS: Sixty extracted maxillary central incisors, with previous root canal treatment, were decoronated and the gutta-percha was completely removed from the root canals. Subsequently, the canals were filled with a calcium hydroxide-based paste composed of calcium hydroxide, bismuth carbonate, and glycerin. The study samples were divided into the following three groups on the basis of three insertion techniques (n = 20, each): conventional technique using a hand instrument (MAN), rotary Lentulo spiral (LEN) technique, and a combined technique combining conventional h…
A study on stress distribution to cement layer and root dentin for post and cores made of CAD/CAM materials with different elasticity modulus in the …
2019
Background To evaluate the stress distribution in a maxillary central incisor with different post and cores made of six CAD/CAM materials with different elastic modulus in the absence of ferrule using the finite element analysis. Material and methods A three-dimensional endodontically treated maxillary central incisor restored with an all-ceramic crown was modelled in Rhinoceros (5.0 SR8, McNeel). The geometries were analyzed in ANSYS 17.2 (ANSYS Inc.) considering isotropic, homogeneous, linearly elastic materials with perfectly bonded contacts. The elastic moduli (E) of the post-and-cores defined the groups to be compared: nanoceramic resin (E=12.8GPa); composite resin (E=16GPa); hybrid ce…
A case of unusual anatomy: a maxillary lateral incisor with three canals.
1999
Case report A case of an unusual maxillary lateral incisor with three root canals is presented. The patient presented with localized swelling and a sinus tract. Because of its abnormal anatomical configuration, the tooth presented diagnostic and procedural difficulties. Conventional root canal treatment was performed successfully.
Endodontic management of type II dens invaginatus with open apex and large periradicular lesion using the XP-endo Finisher : a case report
2018
Dens invaginatus (DI) represents an endodontic challenge because of its complex root canal morphology. This case report presents the clinical management of a 22-year-old woman with type II DI in right maxillary lateral incisor with a painful swelling. Pulp testing revealed no response with the tooth. Type II DI with open apex and large periradicular lesion was seen on radiograph. The treatment was planned by using cone-beam computed tomography (CBCT) imaging. Canal treatment was completed in two appointments with the aid of a dental operating microscope. In the first appointment, the internal anatomy was modified using an ultrasonic tip, and chemo-mechanical preparation was performed using …
Periapical Microsurgery with an Endoscope and Microscope of Two Upper Central Incisors Already Subjected to Periapical Surgery 25 Years Ago
2020
Introduction. The present clinical case describes periapical microsurgery with an endoscope and microscope in a patient already treated 25 years ago due to persistent periapical disease of the two central upper incisors, restored with poorly adapted crowns. Clinical Case. The first periapical surgery had been performed with silver amalgam as a retrograde filler material, causing grayish staining of the buccal mucosa. Periapical surgery was performed raising a submarginal flap with ostectomy and apicoectomy, retrograde cavity preparation with ultrasound tips, and filling with mineral trioxide aggregate (MTA). After soft tissue healing and complete bone regeneration of the lesion, retreatment…
Effect of different mixing and placement methods on the quality of MTA apical plug in simulated apexification model
2017
Background It is necessary apical plug material to exhibit proper adaptation with the root canal walls. Presence of voids at the interface between the root canal wall and this material result in micro leakage, which might have a relationship with post treatment disease. The aim of the present study was to evaluate the effect of different mixing (manual and ultrasonic) and placement (manual and manual in association with indirect ultrasonic) method of Mineral Trioxide Aggregate (MTA) on the void count and dimension in the apical plug in natural teeth with simulated open apices. Material and methods Eighty human maxillary central incisors were selected. After simulation of the open apex model…