Preliminary study: evaluating the reliability of CBCT images for tongue space measurements in the field of orthodontics.

Introduction: Accurately measuring tongue space is challenging, but this information can be useful to many dental specialties. This study was intended to estimate the reliability of using cone-beam computed tomography (CBCT) to measure tongue space, which includes tongue volume and the oral cavity air capacity.

Methods: For this preliminary study, CBCT images from ten participants (five females and five males, mean age of 29.

History and Evolution of Orthognathic Surgery at Chang Gung Craniofacial Center: Lessons Learned From 35-Year Experience.

Background: Modern orthognathic surgery (OGS) was established on the basis of contributions from multidisciplinary centers worldwide. This study reports the history and evolution of OGS at the Chang Gung Craniofacial Center (CGCC) and identifies the lessons learned from 35 years of experience.

Methods: The total number of OGS procedures managed by the CGCC multidisciplinary team between 1981 and 2016 was determined.

Three-dimensional surgical simulation improves the planning for correction of facial prognathism and asymmetry: A qualitative and quantitative study.

Traditional planning method for orthognathic surgery has limitations of cephalometric analysis, especially for patients with asymmetry. The aim of this study was to assess surgical plan modification after 3-demensional (3D) simulation. The procedures were to perform traditional surgical planning, construction of 3D model for the initial surgical plan (P1), 3D model of altered surgical plan after simulation (P2), comparison between P1 and P2 models, surgical execution, and postoperative validation using superimposition and root-mean-square difference (RMSD) between postoperative 3D image and P2 simulation model.

A modified presurgical orthopedic (nasoalveolar molding) device in the treatment of unilateral cleft lip and palate.

Nasoalveolar molding (NAM) can be done effectively to reshape the nasal cartilage and mold the maxillary dentoalveolar arch before surgical cleft lip repair and primary rhinoplasty. Presurgical NAM helps as an adjunct procedure to enhance the esthetic and functional outcome of the surgical procedures. We have developed a modified NAM device to suit to the needs of the patients coming from distant places for the treatment.

Interdental osteotomies induce regional acceleratory phenomenon and accelerate orthodontic tooth movement.

Purpose: Although it has been revealed clinically that double-jaw orthognathic surgery induces a systemic increase in the baseline bone turnover and subsequently accelerates postoperative orthodontic tooth alignment, it is not clear whether less extensive osteotomy, such as interdental osteotomy, would be intensive enough to accelerate postoperative orthodontic tooth alignment.

Materials And Methods: Twelve adult male beagle dogs were randomly assigned to 2 groups. The sham control group (n = 6) received orthodontic tooth alignment of the maxillary incisors, and the experimental group (n = 6) received orthodontic tooth alignment of the maxillary incisors and interdental osteotomies between the maxillary third incisor and canine on both sides concurrent with the beginning of orthodontic tooth alignment.

Surgery-first accelerated orthognathic surgery: postoperative rapid orthodontic tooth movement.

Purpose: Clinically, we have observed the phenomenon of postoperatively accelerated orthodontic tooth movement in patients who had orthognathic surgery. This phenomenon lasts for a period of 3 to 4 months. However, the underlying mechanisms of this phenomenon have not been well studied yet.

Surgery-first accelerated orthognathic surgery: orthodontic guidelines and setup for model surgery.

The surgery-first approach indicates that the orthognathic surgery precedes the orthodontic treatment, whereas the orthodontics-first approach indicates that the orthodontic treatment precedes the orthognathic surgery. The conventional approach is an orthodontics-first approach. The purposes of this article are to introduce the concept of the surgery-first approach and to report the guidelines for orthodontic management and model surgery without presurgical orthodontic decompensation.

A Surgery-first approach in surgical-orthodontic treatment of mandibular prognathism--a case report.

The conventional approach in orthodontic surgery treatment of dentofacial anomalies requires a varied period of pre-surgical orthodontic treatment. This presurgical period is considered to be important for adequate surgical treatment and stable results. This period is usually long bothersome for patients because dental decompensation is required and there is consequent deterioration of aesthetics and function, especially in cases of skeletal Class III occlusion.

Apical root resorption in orthodontic patients with en-masse maxillary anterior retraction and intrusion with miniscrews.

Introduction: The purposes of this retrospective study were to investigate the apical root resorption of maxillary incisors in orthodontic patients with en-masse maxillary anterior retraction and intrusion with miniscrews and the factors disposing a patient to apical root resorption.

Methods: Fifty adult patients with maxillary protrusion were included; 30 were treated with miniscrews and extraction of the maxillary first premolars (group I), and 20 were treated with extraction of the maxillary first premolars (group II). For each patient, periapical films of the maxillary incisors and lateral cephalometric radiographs were taken before and after treatment to evaluate apical root resorption and cephalometric measurements.

Dental and skeletal changes following surgically assisted rapid maxillary anterior-posterior expansion.

Background: Lengthening the maxillary dental arch as a treatment approach for patients with maxillary deficiency and dental crowding is seldom reported. The purpose of this study was to assess dental and skeletal changes in the maxilla in the correction of maxillary deficiency associated with a retruded maxillary arch using a surgically assisted rapid maxillary anterior-posterior expansion appliance.

Methods: Predistraction and postraction lateral cephalometric and periapical radiographs and maxillary dental casts of six young adolescents (four boys, two girls, mean age 11 years, 2 months) were examined.

Comparison of the loading behavior of self-drilling and predrilled miniscrews throughout orthodontic loading.

Introduction: A predrilled miniscrew, when used as a temporary anchorage device in the infrazygomatic crest of the maxilla, can be displaced under orthodontic loading. The purpose of this retrospective cephalometric study was to compare the loading behavior of predrilled and self-drilling miniscrews placed in the infrazygomatic crest of the maxilla.

Methods: The subjects were 32 women who had miniscrews in the infrazygomatic crest of the maxilla as skeletal anchorage for en-masse anterior retraction and intrusion; 16 had predrilled miniscrews, and 16 had the self-drilling type.

A comparative evaluation of current orthodontic miniscrew systems.

Miniscrew placement has achieved widespread acceptance in orthodontic practice. However, selecting a suitable miniscrew system from among the available brands is not easy. The aim of this article is to help the clinician better understand the features of miniscrew systems currently available on the market and provide a useful guideline for their clinical use.

Long-term follow-up after maxillary distraction osteogenesis in growing children with cleft lip and palate.

Objective: To evaluate the changes in maxillary position after maxillary distraction osteogenesis in six growing children with cleft lip and palate.

Design: Retrospective, longitudinal study on maxillary changes at A point, anterior nasal spine, posterior nasal spine, central incisor, and first molar.

Setting: The University Hospital Craniofacial Center.

A computed tomographic image study on the thickness of the infrazygomatic crest of the maxilla and its clinical implications for miniscrew insertion.

Introduction: The purpose of this study was to measure the thickness of the infrazygomatic (IZ) crest above the maxillary first molar at different angles and positions to the maxillary occlusal plane. These measurements were then used to derive clinical implications and guidance for inserting miniscrews in the IZ crest without injuring the mesiobuccal root of the maxillary first molar.

Methods: Computed tomographic images of 16 adults were used.

Distraction osteogenesis in adolescents with maxillary arch deficiency and dental crowding: a 3-year follow-up.

Background: In this study, the authors evaluated the long-term results after using anterior segmental osteotomy and distraction osteogenesis for the correction of sagittal maxillary deficiency associated with dental crowding.

Methods: Six young adolescents (four boys and two girls) underwent surgery and distraction at a mean age of 11.2 years (range, 10 to 12 years) and were followed up for 3 years.

Mandibular remodeling after bilateral sagittal split osteotomy for prognathism of the mandible.

Purpose: To describe the postoperative remodeling changes in the mandible after bilateral sagittal split osteotomy to correct mandibular prognathism.

Patients And Methods: Twenty patients who underwent bilateral sagittal split osteotomy for the correction of mandibular prognathism were studied for postoperative remodeling changes within the mandible. The 6-week, 1-year, and long-term postoperative cephalometric mandibular tracings of 12 patients were superimposed using the fixation wires as the stable reference points to demonstrate the specific locations of the intrabony remodeling.

Do miniscrews remain stationary under orthodontic forces?

Miniscrews have been used in recent years for anchorage in orthodontic treatment. However, it is not clear whether the miniscrews are absolutely stationary or move when force is applied. Sixteen adult patients with miniscrews (diameter = 2 mm, length = 17 mm) as the maxillary anchorage were included in this study.