Micro-computed tomographic evaluation of the effect of fluoride agents on white spot lesions: An study.

Objective: To investigate remineralizing effect of three fluoride regimens on artificially demineralized enamel around orthodontic bracket by analyzing mineral density (MD) acquired from micro-computed tomography (micro-CT).

Methods: Forty-eight bracket bonded bovine incisors were prepared to create demineralized enamel (DE) surface. The samples were divided into four groups according to the fluoride regimen: 1) no fluoridation, 2) 1.

Prediction of hand-wrist maturation stages based on cervical vertebrae images using artificial intelligence.

Objective: To predict the hand-wrist maturation stages based on the cervical vertebrae (CV) images, and to analyse the accuracy of the proposed algorithms.

Settings And Population: A total of 499 pairs of hand-wrist radiographs and lateral cephalograms of 455 orthodontic patients aged 6-18 years were used for developing the prediction model for hand-wrist skeletal maturation stages.

Materials And Methods: The hand-wrist radiographs and the lateral cephalograms were collected from two university hospitals and a paediatric dental clinic.

A long-term longitudinal study of the osteoarthritic changes to the temporomandibular joint evaluated using a novel three-dimensional superimposition method.

The aim of this study was to assess the changes in individual condyles from 5 to 8 years in patients with temporomandibular joint (TMJ) osteoarthritis using 3-dimensional cone beam computed tomography (3D CBCT) reconstruction and superimposition. To assess the longitudinal TMJ changes, CBCT was performed at initial (T) and final (T) timepoints that were at least 5 years apart and at a middle (T) timepoint. To improve the accuracy, we used a novel superimposition method that designated areas of coronoid process and mandibular body.

Decreased maxillary sinus volume is a potential predictor of obstructive sleep apnea.

Objectives: To investigate the associations between nasal airway volume and the presence and severity of obstructive sleep apnea (OSA) in adults.

Materials And Methods: The medical records of adult patients who visited the sleep clinic at University Hospital between June 2013 and April 2017 and underwent overnight polysomnography for the diagnosis of obstructive sleep apnea were reviewed retrospectively. Using computed tomography, the volumes of the nasal airways and maxillary sinuses were measured, and associations with the presence and severity of OSA were analyzed while controlling for the effects of possible confounders such as lateral cephalometric variables, maxillary widths, tongue/hyoid position, and soft palate dimensions.

Factors associated with spontaneous mesialization of impacted mandibular third molars after second molar protraction.

Objectives: To investigate factors associated with spontaneous mesialization of impacted third molars after second molar protraction to close the space caused by a missing mandibular first molar (L-6) or retained deciduous mandibular second molars with a missing succedaneous premolar (L-E).

Materials And Methods: Panoramic radiographs of patients treated with mandibular second molar protraction to close the space due to missing L-6 or L-E (14 males, 36 females, mean age = 18.6 ± 4.

Influence of changing various parameters in miniscrew-assisted rapid palatal expansion: A three-dimensional finite element analysis.

Objective: This study aimed to analyze the effect of changing various parameters of the bone-borne rapid palatal expander (RPE) using the finite element method (FEM).

Methods: In eight experimental groups, we investigated the effect of the number, position, and length of miniscrews; positional changes of the expander; and changes in the hook length on maxillary expansion. In finite element analysis, we compared the magnitude and distribution of stress, and the displacement changes following expansion of the bone-borne RPE.

Comparison of antimicrobial activity of traditional and new developed root sealers against pathogens related root canal.

Background/purpose: Bacterial infection is closely associated with the failure of endodontic treatment, and use of endodontic sealer with antimicrobial activity and biological compatibility is necessary for the success of root canal treatment. The purpose of this study was to investigate and to compare the antibacterial effect of two calcium silicate-based root canal sealers (Endoseal and EndoSequence BC sealer) as recent development sealers and with three conventional root canal sealers (AH Plus, Sealapex, and Tubli-Seal), before or after setting, on , and

Materials And Methods: The sealers were soaked in phosphate buffered saline to elute its compositions after and before setting, and the elutes were performed the antimicrobial assay. Also, X-ray fluorescence analysis was carried out to compare compositions of two calcium silicate-based sealers.

Change in alveolar bone level of mandibular second and third molars after second molar protraction into missing first molar or second premolar space.

Objective: To investigate the factors associated with the change in alveolar bone level of mandibular second and third molars after second molar protraction into the space of the missing first molar (L6) or second premolar (LE).

Methods: Fifty-one patients in whom space of the missing L6 or LE was treated with second molar protraction (13 males, 38 females, mean age 19.6 ± 4.

Colorimetric evaluation of white spot lesions following external bleaching with fluoridation: An study.

Objective: This study was performed to investigate the effects of external tooth bleaching with flouridation on the appearance of white spot lesions (WSLs) .

Methods: In total, 125 bracket-bonded bovine incisor enamel blocks with artificial WSLs were randomly divided into a control group and four treatment groups (home bleaching, home bleaching + fluoridation, in-office bleaching, and in-office bleaching + fluoridation). A spectroradiometer (SR) and digital images (DIs) were used to evaluate colorimetric parameters (Commission Internationale l'Eclairage Lab) for all specimens.

3-D finite element analysis of the effects of post location and loading location on stress distribution in root canals of the mandibular 1st molar.

Objective The purpose of this study was to evaluate, by using finite element analysis, the influence of post location and occlusal loading location on the stress distribution pattern inside the root canals of the mandibular 1st molar. Material and Methods Three different 3-D models of the mandibular 1st molar were established: no post (NP) - a model of endodontic and prosthodontic treatments; mesiobuccal post (MP) - a model of endodontic and prosthodontic treatments with a post in the mesiobuccal canal; and distal post (DP) - a model of endodontic and prosthodontic treatments with a post in the distal canal. A vertical force of 300 N, perpendicular to the occlusal plane, was applied to one of five 1 mm2 areas on the occlusal surface; mesial marginal ridge, distal marginal ridge, mesiobuccal cusp, distobuccal cusp, and central fossa.

Factors associated with long-term vertical skeletal changes induced by facemask therapy in patients with Class III malocclusion.

Objectives: This study investigated the long-term vertical skeletal changes induced by facemask therapy in patients with Class III malocclusion and different vertical skeletal patterns.

Materials And Methods: A total of 54 patients (20 boys and 34 girls; mean age, 7.7 ± 2.

Bone availability for mandibular molar distalization in adults with mandibular prognathism.

Objectives: To investigate the retromolar space available for molar distalization in patients with mandibular prognathism.

Materials And Methods: Using cone-beam computed tomography, the posterior mandibular dimensions in 110 consecutive patients with Class I or Class III malocclusion were measured (mean age, 27.0 ± 7.

Bond Strengths of Orthodontic Metal Brackets to Tribochemically Silica-coated Zirconia Surfaces Using Different 10-Methacryloyloxydecyl Dihydrogen Phosphate-containing Primers.

Purpose: To evaluate the effects of tribochemical silica coating and different 10-methacryloyloxydecyl dihydrogen phosphate (MDP)-containing primers on the shear bond strength (SBS) of orthodontic metal brackets to yttrium-stabilized tetragonal zirconia polycrystal (Y-TZP) surfaces.

Materials And Methods: One hundred ninety polished Y-TZP specimens were randomly assigned to 19 groups (n = 10): 30 specimens were used for surface analyses after polishing with 600-grit silicon carbide paper, airborneparticle abrasion with 50-μm alumina (A), or tribochemical silica coating (CoJet [C]); 160 specimens were used in SBS testing of orthodontic metal brackets to Y-TZP after alumina airborne-particle abrasion or tribochemical silica coating and application of either ESPE-Sil (S) (ASn, ASa, CSn, CSa), Alloy Primer (AP) (AAPn, AAPa, CAPn, CAPa), Clearfil Ceramic Primer (CP) (ACPn, ACPa, CCPn, CCPa), or Scotchbond Universal (U) (AUn, AUa, CUn, CUa) and either stored in water for 24 h (non-aged, n) or thermocycled 5000 times (aged, a). The surface analyses and SBSs were statistically analyzed with ANOVA and Tukey's tests.

Dimensional accuracy of ceramic self-ligating brackets and estimates of theoretical torsional play.

Objective: To ascertain the dimensional accuracies of some commonly used ceramic self-ligation brackets and the amount of torsional play in various bracket-archwire combinations.

Materials And Methods: Four types of 0.022-inch slot ceramic self-ligating brackets (upper right central incisor), three types of 0.

Effect of Co doping concentration on structural properties and optical parameters of Co-doped ZnO thin films by sol-gel dip-coating method.

The structural and optical properties of Co-doped ZnO thin films prepared by a sol-gel dip-coating method were investigated. X-ray diffraction analysis showed that the thin films were grown with a c-axis preferred orientation. The position of the (002) peak was almost the same in all samples, irrespective of the Co concentration.

In vitro microleakage of six different dental materials as intraorifice barriers in endodontically treated teeth.

The aim of this study was to compare the coronal sealing ability of six different dental materials: Three MTA-based cements and three established restorative materials by in vitro dye penetration method. For in vitro infiltration experiments, seventy extracted single-rooted human teeth were used. After crowns of teeth were reduced, root canals were prepared, and filled with gutta-percha cone.

The relation between idiopathic scoliosis and the frontal and lateral facial form.

Objective: The purpose of this study was to evaluate the relation between idiopathic scoliosis and facial deformity in the horizontal, vertical, and anteroposterior planes.

Methods: A total of 123 female patients aged 14 years or older, who visited the Spine Clinic at the Department of Orthopedics, Korea University Guro Hospital for treatment of idiopathic scoliosis, were enrolled. Whole-spine anteroposterior and lateral radiographs were taken with the patient in a naturally erect position, and frontal and lateral cephalograms were taken in an erect position with the Frankfort horizontal line parallel to the floor.

The predictability of dentoskeletal factors for soft-tissue chin strain during lip closure.

Objective: To investigate the dentoskeletal factors which may predict soft-tissue chin strain during lip closure.

Methods: The pretreatment frontal and lateral facial photographs and lateral cephalograms of 209 women (aged 18-30 years) with Angle's Class I or II malocclusion were examined. The subjects were categorized by three examiners into the no-strain and strain groups according to the soft-tissue chin tension or deformation during lip closure.

The effect of silver ion-releasing elastomers on mutans streptococci in dental plaque.

Objective: The purpose of this study was to investigate the antimicrobial effect of silverized elastomers on mutans streptococci in dental plaque.

Methods: Forty patients undergoing orthodontic treatment were randomly placed into 1 of 2 groups. We examined the maxillary right and left central incisors and premolars, and the mandibular right and left canines of all participants.

Temperature dependence of indigo light emission from mesoporous ZnO/porous silicon nanocomposites.

Nanocomposites of mesoporous zinc oxide (ZnO) and porous silicon (PS) were prepared through a hydrothermal method. Room-temperature (RT) and temperature-dependent photoluminescence (PL) were performed to investigate the optical properties and temperature dependence of the indigo emission peak from the ZnO/PS nanocomposites. An indigo emission peak from the nanocomposites and a red emission peak from the PS were observed in the case of the mesoporous ZnO/PS nanocomposites.

Magnesium content ratio effects of MgxZn1-xO seed layers on structural and optical properties of ZnO nanorods.

ZnO nanorods were grown on MgxZn1-xO seed layers with different content ratio ranging from 0 to 0.3 by hydrothermal method. Scanning electron microscopy (SEM), X-ray diffraction (XRD), and photoluminescence (PL) were carried out to investigate the effects of Mg content ratio for the MgxZn1-xO seed layers on the structural and optical properties of the ZnO nanorods.

Effects of precursor concentrations and thermal annealing on ZnO nanorods grown by hydrothermal method.

ZnO nanorods were grown on spin-coated ZnO seed layers by hydrothermal method. The ZnO nanorods were grown with various precursor concentrations ranging from 0.01 to 0.

Correlation between facial asymmetry, shoulder imbalance, and adolescent idiopathic scoliosis.

We conducted a prospective cross-sectional study to examine the correlation between facial asymmetry, shoulder imbalance, and adolescent idiopathic scoliosis. Sixty-nine adolescent idiopathic scoliosis patients and 29 healthy volunteers were enrolled in this study. All patients underwent whole-spine standing anteroposterior radiographs and frontal cephalograms.

Influence of orthodontic adhesives and clean-up procedures on the stain susceptibility of enamel after debonding.

Objective: To determine the influence of the type of orthodontic adhesive system, such as conventional acid-etching (CE) and self-etching primers (SEPs), on the stain susceptibility of enamel surface after debonding. Effects of clean-up procedures on the enamel surface were also determined.

Materials And Methods: Two types and four brands of adhesive systems were investigated using 135 human premolars.