Comparison of the morphology of the primary first molars and the forms of stainless steel crowns used in clinical practice.

This study aimed to assess the difference in the mesiodistal (MD) and buccolingual (BL) dimensions of primary first molars between Taiwanese boys and girls using a three-dimensional (3D) scanner (Microscribe G2 digitizer), record the coordinates in the 3D systems of Graph-R Project and reconstruct 3D images for subsequent analysis. We also determined whether the differences in these parameters between primary first molars and stainless steel crowns (SSC, 3M ESPE, No. 2-7) could be used as a reference for selecting a suitably-sized SSC and performing adjustments during restoration.

A comparative study of propofol alone and propofol combined with midazolam for dental treatments in special needs patients.

Although dental treatment with sedation is performed increasingly in special needs patients, data on adding midazolam to intravenous propofol sedation are very limited for this group. The purpose of this study was to identify the factors and procedure time associated with the use of intravenous sedation with propofol alone or propofol combined with midazolam in dental patients with special needs.This was a retrospective data analysis.

Application of the Integrated Behavioral Model to oral self-care behavior of community-dwelling middle-aged and older people in Taiwan.

Objectives: This study evaluated the Integrated Behavioral Model and examined oral self-care behavior of community-dwelling middle-aged and older people.

Design: A cross-sectional design was used.

Sample: Purposive sampling was employed to recruit middle and older age community-dwelling individuals, with research locations in public health centers in northern Taiwan.

Prevalence of primate and interdental spaces for primary dentition in 3- to 6-year-old children in Taiwan.

Background/purpose: Spaced primary dentition plays a critical role in the eruption of permanent teeth and the establishment of ideal occlusion. A lack of these spaces in deciduous dentition may result in disproportionate jaw and tooth sizes. Additionally, spaced primary dentition is significantly affected by ethnic factors.

Bite-force difference among obese adolescents in central Taiwan.

Background/purpose: Maximal bite force of the jaw can cause thorough food chewing and result in good digestion. Bite force is related to the health of the masticatory muscles. Muscle force is frequently affected by obesity in adolescence, however, little is known about how obesity influences the maximum bite force and the difference between genders.

The role of IL-8 in the SDF-1α/CXCR4-induced angiogenesis of laryngeal and hypopharyngeal squamous cell carcinoma.

Stromal cell-derived factor-1 (SDF-1) (CXCL12) has been observed to promote laryngeal and hypopharyngeal squamous cell carcinomas (LHSCCs) invasion through cooperation with its receptor CXCR4. Here, we further explore the angiogenesis mechanism induced by SDF-1/CXCR4 interaction in LHSCCs. Immunohistochemistry (IHC) reveals the significant correlation between CXCR4 and angiogenesis in tumors.

Retropalatal Müller grade is associated with the severity of obstructive sleep apnea in non-obese Asian patients. Retropalatal Müller grade and OSA in non-obese.

Purpose: The aim of this study was to investigate whether physical evaluations could be used for predicting the presence and severity of obstructive sleep apnea (OSA) in non-obese snoring patients.

Methods: This is a retrospective study, and a total of 244 non-obese (body mass index, BMI, <27 kg/m(2)) snoring patients (178 men and 66 women; mean age = 43.1 ± 12.

Bond strength of orthodontic light-cured resin-modified glass ionomer cement.

The purpose of this study was to compare the bond strengths and debonded interfaces achieved with light-cured resin-modified glass ionomer cement (RMGIC) and conventional light-cured composite resin. In addition, the effects of acid etching and water contamination were examined. One hundred human premolars were randomly divided into five equal groups.

Orthodontic bonding with self-etching primer and self-adhesive systems.

The purpose of this study was to compare the tensile bond strengths of orthodontic brackets bonded to enamel using conventional multi-step adhesive, self-etching primer (SEP), which combines etching and priming into a single step, and self-adhesive systems, which combine etchant, primer, and adhesive. Metal brackets were bonded to 90 extracted human premolars according to three experimental protocols: group 1, conventional multi-step adhesive system; group 2, SEP; and group 3, self-adhesive system. All specimens were debonded using an Instron universal machine and failures between the tooth surface and bracket base were observed by scanning electron microscopy (SEM).

Increasing humidity blocks continuous positive airflow-induced apnea responses in rats.

Background: The aim of this study was to investigate the role of temperature and humidity in positive continuous pressure flow-induced apnea.

Methods: Forty-two adult male Sprague-Dawley rats were used in a functionally isolated laryngeal animal model. In study 1, animals were challenged with laryngeal stimulation for 1 minute to detect the possibility of adaptation.

Treatment of large jaw bone cysts in children.

Odontogenic cysts are classified into 2 main types based on their formation mechanism: inflammatory and developmental. Radicular cysts are the most common inflammatory cysts, while dentigerous cysts are developmental cysts. We report 2 radicular cysts that developed at the apices of nonvital primary teeth and 2 dentigerous cysts.

Developmental changes in pharyngeal airway depth and hyoid bone position from childhood to young adulthood.

Objective: (1) To test the hypothesis that there are no developmental changes in the pharyngeal airway depth and hyoid bone position from childhood to adulthood in normal Taiwanese persons, (2) to identify any sexual dimorphism, and (3) to find the predictive value of selective variables for the hyoid bone position.

Materials And Methods: Lateral cephalometric radiographs of 239 normal Taiwanese (132 females and 107 males; aged 7-27 years) were separated into three stages according to dental age. Twenty-three linear and 20 angular measurements were made in all subjects.

Sex differences in anthropometric and cephalometric characteristics in the severity of obstructive sleep apnea syndrome.

Introduction: Craniofacial anatomic abnormalities related to structural narrowing of the upper airway have been reported in patients with obstructive sleep apnea syndrome (OSAS). The purpose of this study was to test whether there are sex differences in the relative contributions of specific anthropometric and cephalometric measurements of OSAS severity.

Methods: The subjects were Taiwanese patients who visited the Ear, Nose, and Throat Department of National Taiwan University Hospital with complaints of snoring or sleep apnea.

Ozone-induced nasal hyperresponsiveness to tachykinins in guinea pigs.

Objective: To assess role of hydroxyl radials in the ozone-induced upper airway hyper-responsiveness to tachykinins.

Methods: A prospective, controlled, animal model (n = 96) was performed. Half of them exposed to air (A-group, placebo) and the other half exposed to 3 ppm ozone (O-group) for 2 h.

Cephalometric analysis of nonobese snorers either with or without obstructive sleep apnea syndrome.

Objective: To determine if there is an indicator on the lateral cephalometric radiograph that can be used for the differential diagnosis of severe obstruct sleep apnea syndrome and simple snoring in nonobese young male adults.

Materials And Methods: The subjects were Taiwanese male patients with a complaint of snoring and/or sleep apnea, whose body mass index was less than 25 kg/m(2) and who were younger than 40 years old. Forty-six patients with severe obstructive sleep apnea and 36 patients with simple snoring were selected and underwent lateral cephalometric radiography, from which 24 linear and 34 angular measurements were calculated.

Developmental changes of pharyngeal airway structures from young to adult persons.

This cross-sectional study investigated developmental changes of pharyngeal airway structures. The materials were comprised of 120 lateral cephalometric radiographs and were divided into three stages according to the dental age. Results indicated that the upper pharyngeal depth increased with age, whereas, the lower pharyngeal depth was established early in life.

Factors associated with mandibular third molar eruption and impaction.

A retrospective study, using panoramic radiographs, was conducted on 152 Taiwanese (72 males and 80 females) to investigate mandibular third molar eruption and impaction. The following measurements were made: inclinations and mesiodistal crown widths of the mandibular molars, vertical and horizontal spaces between the distal surface of the second molar and the anterior surface of the ramus, lengths and widths of the mandibular ramus and body, the ramus inclination, the mandibular plane angle, and the mandibular gonial angle. Differences between non-impaction and impaction groups were studied, and the variables were analyzed with multivariate discriminatory analysis.

Morphology of the palatal vault of primary dentition in transverse view.

The purpose of this study was to investigate the transverse view of the morphology of the palatal vault in the primary dentition at the primary second molar level. Observations were obtained from 150 dental stone casts of normal children (78 boys and 72 girls; aged four to five years). Palatal width, palatal depth, arch width, and primary second molar angulation were measured.

Growth changes of general and dental health status in Taiwanese children from mixed to early permanent dentition.

For this study, the general and dental health status of 463 Taiwanese children aged 9 to 12 years was evaluated. There were statistically significant increases in all measurements from Hellman's dental developmental stages IIIA to IVA except for the maximum mandibular protrusive, right lateral, and left lateral movements. Maximum bite forces had diminished in stage IIIB.

Positional changes of the upper canine and posterior teeth, hard palate, and sinus floor from primary to permanent dentition.

This cross-sectional study investigated normal positional changes of the upper permanent canine and posterior teeth, hard palate, and sinus floor in normal Taiwanese children from the deciduous to early permanent dentition. In total, 261 panoramic radiographs were used. During the observation period, almost all structures changed their positions toward the distal and occlusal direction.

Panoramic radiographic findings of the mandibular foramen from deciduous to early permanent dentition.

The purpose of this study was to investigate the position of the mandibular foramen from deciduous (Hellman's stage IIA) to early permanent dentition (Hellman's stage IVA). Panoramic radiographs of 311 Taiwanese children were used. The results revealed that the distances between the mandibular foramen and ramus anterior plane were greater than those between the mandibular foramen and ramus posterior plane through all stages.

Maximum bite force and related dental status in children with deciduous dentition.

Six hundred seventy-six Taiwanese children with deciduous dentition were sampled for maximum bite force and related dental status. Sixty-seven percent of children had at least one decayed tooth. The mean number of decayed teeth of all children was 2.

Dental crowding in primary dentition and its relationship to arch and crown dimensions.

Purpose: The purpose of this study was to compare dental arch size, mesiodistal and buccolingual crown widths, and crown shapes between 2 groups of children, 1 with anterior crowding in both dental arches and another with anterior spacing in both dental arches.

Methods: Sixty-one sets (27 crowded and 34 spaced arches) of dental casts of normal occlusions were examined.

Results: For both lower and upper arches, crowded arches had statistically significantly smaller arch widths than did the spaced arches.

Variations among the primary maxillary dental arch forms using a polynominal equation model.

This study identifies arch symmetry and describes arch form variations in normal primary maxillary dental casts. Sixty-two percent of casts had asymmetrical arches, and 38% had symmetrical arches. Six types of arch form were identified according to the ratio of arch width to length.

A computerized analysis of dental arch morphology in early permanent dentition.

To determine the positions of teeth and the size and shape of the dental arches, 53 dental casts of children (29 boys and 24 girls) with their early permanent dentition and normal occlusions were examined. The coordinates of cusp tips and line angles of anterior teeth and cusp tips, contact points, and fossa of posterior teeth were digitized. Computer-generated curves were created for both arches using a polynomial model.