Comparison of the skeletodental effects of miniscrew-anchored and tooth-anchored facemask treatment in growing patients with skeletal class III malocclusions.

INTRODUCTION: This retrospective study aimed to evaluate the skeletal and dental effects of the miniscrew-anchored facemask in skeletal Class III growing patients and compare them with those of conventional tooth-anchored facemasks. METHODS: Retrospectively a total of 50 patients with skeletal Class III (mean ANB: -1.12°) were investigated and divided into two groups according to the treatment modality. Twenty-five patients were treated using the conventional tooth-anchored facemask (T group: mean age 9.3 ± 1.1 years, mean ANB: -0.93°) whereas the other 25 were treated using a miniscrew-anchored facemask (M group: mean age 9.7 ± 1.3 years. mean ANB: -1.61°). Two miniscrews were placed on the palate for bone anchorage. In both T and M groups, facemasks applied a force of 20-30° down on the occlusal plane, and the force increased from 200 g to 300-350 g per side throughout the treatments. The patients were instructed to wear facemasks for at least 14 h per day. A total of 16 angular and 11 linear cephalometric measurements were analysed to determine the skeletal and dental changes before and after facemask treatment. A paired t-test was used to verify the effects before and after treatment in each group. RESULTS: All miniscrews were well maintained during treatment. The values of SNA, SN-ANS, ANB and A to N-Perp, which indicate anterior protraction of the maxilla, were significantly higher in the M group compared with the T group (P < .05). Proclination of the maxillary incisors, extrusion and mesialization of the maxillary molars were significantly greater in the T group (P < .05). CONCLUSIONS: Miniscrew-anchored facemask treatment increased the amount of maxillary protraction and reduced the dental side effects compared with conventional tooth-anchored facemask treatment in growing patients with skeletal Class III malocclusion.

The current status of orthodontic education in U.S. pediatric dental residencies.

PURPOSE/OBJECTIVES: The purpose of this study was to survey the current status of orthodontic education at pediatric dental residencies in the United States. A similar survey was conducted >10 years ago. With changing healthcare politics, social demands, and technology, it is important to have current information about dental education. METHODS: A 23-item anonymous survey was sent to individual pediatric dental residency program directors via Qualtrics email software. The survey was sent a total of 4 times over an 8-week period. If the surveys were not completed in a predetermined amount of time, they were resent to those who had not yet completed them. RESULTS: There were 34 responders for a 24% response rate. Of the respondents, 73% reported teaching biomechanics of tooth movement, and 45% reported teaching 2 × 4 mechanics to "marginally acceptable" level. Early (91%) to late mixed dentition (77%) is the most commonly treated orthodontic case. While most programs do not require a minimum number of orthodontic cases for graduation (85%), residents' understanding of growth and development is mostly (71%) evaluated through the results of the American Board of Pediatric Dentistry Qualifying Examination. CONCLUSION: This study summarizes the current climate of the orthodontic education component in U.S. pediatric dental residencies.

Anterior open bite due to idiopathic condylar resorption during orthodontic retention of a Class II Division 1 malocclusion.

A common dilemma when treating anterior open bite is understanding its etiology. Idiopathic condylar resorption (ICR) can cause open bite in affected individuals. Although it is prudent to not treat patients with ICR until active resorption has ceased, orthodontists may begin treating them because anterior open bite from ICR may not appear before or during their orthodontic treatment. This article reports a 12-year-old female who was diagnosed with ICR 10 months after completion of her orthodontic treatment for a Class II Division 1 malocclusion. When a young patient with a high mandibular angle and previous skeletal or dental Class II malocclusion returns with an open bite during the retention phase, the patient's condyles must be carefully examined to determine whether any temporomandibular joint disorder, such as ICR, is present. Currently, the controversy over the cause and the cure for ICR is continuing to challenge orthodontists in diagnoses and treatments. Orthodontists should closely monitor and offer informed treatment options to patients with risk factors for ICR or signs of its pathology that might develop at any stage of orthodontic treatment, including the retention period.

Electrical characterization of N- and P-doped hole and electron only organic devices.

We have fabricated a series of hole only devices with tungsten oxide (WO3) and molybdenum oxide (MoO3) n-doping materials in N,N'-diphenyl-N,N'-bis(1,1'-biphenyl)-4,4'-diamine (NPB) hole transport layer, and electron only devices with CsF and Cs2CO3 p-doping materials in 4,7-diphenyl-1,10-phenanthroline (Bphen) electron transport layer. Current-voltage characteristics and conductivity of these devices are investigated. The optimal conditions for ohmic injection and low resistance properties, and process margins of each dopant are reported in this paper.