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.

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.

Three-dimensional evaluation of soft tissue change gradients after mandibular setback surgery in skeletal Class III malocclusion.

Objective: To evaluate whether mandibular setback surgery (MSS) for Class III patients would produce gradients of three-dimensional (3D) soft tissue changes in the vertical and transverse aspects.

Materials And Methods: The samples consisted of 26 Class III patients treated with MSS using bilateral sagittal split ramus osteotomy. Lateral cephalograms and 3D facial scan images were taken before and 6 months after MSS, and changes in landmarks and variables were measured using a Rapidform 2006.

Skeletal changes of maxillary protraction without rapid maxillary expansion.

Objective: To determine potential differences in treatment efficiencies of face mask therapy without rapid maxillary expansion (RME) at different early dental stages.

Materials And Methods: Forty-nine Class III children who were treated with a face mask without RME were divided into two groups according to their pretreatment dental stage. The primary dentition treatment group consisted of 26 subjects and the mixed dentition treatment group consisted of 23 subjects.

Three-dimensional evaluation of soft tissue changes after mandibular setback surgery in class III malocclusion patients according to extent of mandibular setback, vertical skeletal pattern, and genioplasty.

Objective: To investigate the 3-dimensional (3D) changes in the soft tissue after mandibular setback surgery (MSS).

Study Design: Thirty-three skeletal class III malocclusion (SCIII) patients treated with MSS (bilateral sagittal split ramus osteotomy) were subdivided according to extent of MSS, vertical skeletal pattern (VP), and vertical-reduction genioplasty. Lateral cephalograms and 3D facial scan images were taken before and 6 months after surgery.

Three-dimensional quantification of adhesive remnants on teeth after debonding.

Introduction: The objective of this study was to determine 3 dimensionally the amount of adhesive remaining on teeth after debonding orthodontic brackets.

Methods: Three kinds of adhesives were investigated. Metal brackets were bonded to 45 extracted premolars (15 for each adhesive).

Force delivery properties of thermoplastic orthodontic materials.

Introduction: Our objectives were to evaluate the force and energy (resilience) delivery properties of thermoplastic overlay orthodontic materials and to determine the changes in force delivery properties after thermocycling or repeated load cycling.

Methods: Three types and 3 thicknesses of materials were investigated. Three-point bending-recovery tests were performed at baseline and after cycling procedures.

Effect of surface treatment and type of cement on the retentive strength of orthodontic bands on gold alloy crowns.

Introduction: The objective of this study was to evaluate the effect of surface treatment of gold alloy crowns and type of cement on the retentive strength of orthodontic bands cemented on gold alloy crowns.

Methods: Two hundred eight crowns, made of type IV dental gold alloy, were divided into 16 groups based on surface treatment (C, no treatment; S, sandblasting; V, V-Primer; and S + V, sandblasting and V-Primer) and band cement (resin-modified glass ionomer cement, compomer, composite resin, and adhesive resin cement). Bands were cemented on the crowns, and tensile loads were applied to measure the retentive strength.

Influence of light transmittance and background reflectance on the light curing of adhesives used to bond esthetic brackets.

Introduction: The objectives of this study were to determine the correlation between diffuse light transmittance (DLT) of esthetic brackets and the degree of cure (DC) of light-cured adhesives after direct irradiation, and to evaluate the influence of background reflectance. The influences of curing unit and irradiation time were also determined.

Methods: The DLT of 4 ceramic and 4 plastic brackets was measured.

Influence of filler distribution on the color parameters of experimental resin composites.

Objectives: Simulating the optical properties of natural tooth would be the final goal for esthetic restorative materials. Filler distribution in resin composites determines the scattering in composite materials, which in turn would influence the color parameters such as lightness, chroma and hue. The objective of this study was to determine the influence of filler size and amount on the color parameters of experimental resin composites.

Common mode noise cancellation for electrically non-contact ECG measurement system on a chair.

Electrically non-contact ECG measurement system on a chair can be applied to a number of various fields for continuous health monitoring in daily life. However, the body is floated electrically for this system due to the capacitive electrodes and the floated body is very sensitive to the external noises or motion artifacts which affect the measurement system as the common mode noise. In this paper, the Driven-Seat-Ground circuit similar to the Driven-Right-Leg circuit is proposed to reduce the common mode noise.

A Preliminary Study for Unconstrained Pulse Arrival Time (PAT) Measurement on a Chair.

A method of measuring the pulse arrival time (PAT) non-consciously on a chair is proposed. In this method, the electrically non-contact ECG measurement system and the air cushion with balancing tubes are used. In this paper, the correlation between the typical PAT and the unconstrained PATs (A-PATs) are compared.

The ECG measurement in the bathtub using the insulated electrodes.

The ECG recording in the bathtub was studied using insulated electrode. Prior studies of the ECG recording in the bathtub used conductive electrodes having some problems such as the possibility of the electric shock and sensitivity to contamination of the electrode surfaces. The insulated electrodes were made of copper plate coated with PET film.

The electrically non-contacting ECG measurement on the toilet seat using the capacitively-coupled insulated electrodes.

The studies of ECG measurement on the toilet seat have been performed specifically for the ubiquitous health care. Instead of the mainly used dry electrodes having several problems such as the electrical safety or the environmental stability, we used the capacitively-coupled insulated electrodes, which were composed of the Cu plate and the PTFE film for the measurement. The biosignal sensed with the insulated electrodes was measured through the ultra-high input impedance system including OPA111 having the common mode impedance of 10/sup 14/ Omega ft.

Fluorescent emission of varied shades of resin composites.

Objectives: The objectives of this study were to measure the fluorescent emission and the corresponding color difference by the inclusion and exclusion of the UV component of the standard illuminant D65 of varied shades of commercial resin composites, and to determine the influence of the color parameters and difference in color parameters by the UV component on the color difference caused by the fluorescent emission.

Method: Eight light-curing resin composites, a total of 41 shades, were studied. Color and spectral reflectance of specimens, 12 mm in diameter and 1mm in thickness, were measured on a reflection spectrophotometer.

Comparison of the color of natural teeth measured by a colorimeter and Shade Vision System.

Objectives: The objectives were to measure the difference in the color and color parameters of natural teeth measured by a tristimulus colorimeter (CM, used as a reference) and Shade Vision System (SV), and to determine the influence of color parameters on the color difference between the values measured by two instruments.

Method: Color of 12 maxillary and mandibular anterior teeth was measured by CM and SV for 47 volunteers (number of teeth=564). Color parameters such as CIE L*, a* and b* values, chroma and hue angle measured by two instruments were compared.

Changes in scattering and absorption properties of esthetic filling materials after aging.

Objectives: Assuming that color changes after aging are related to changes in translucency of materials, the purpose of the present study was to determine the correlation between the changes in color and the changes in scattering and absorption properties after accelerated aging with representative dental esthetic restorative materials: glass ionomer, resin-modified glass ionomer, compomer, and resin composite.

Methods: Color was measured according to the CIELAB color scale in the transmittance and reflectance modes and used to calculate changes in color (deltaE*(ab)), color coordinates (deltaL*, delta a*, and delta b*), translucency parameter (deltaTP), scattering coefficient (deltaS), absorption coefficient (deltaK), and light reflectivity (deltaRI) after accelerated aging. Simple correlations between each pair of the changes in optical values were calculated, and multiple regression analysis was used to determine the parameters influencing the changes in color and color coordinates (p = 0.