A 10-year trend of dental treatments under general anesthesia of children in Taipei Veterans General Hospital.

BACKGROUND: General anesthesia (GA) as a pediatric dental procedure is a well-established method of behavior management. However, studies of pediatric dentistry under GA have mostly focused on handicapped patients, and various retrospective studies in Taiwan have mainly reviewed only a limited number of years. The purpose of the present study was to report trends in pediatric dental treatment performed under GA over the past 10 years. METHODS: A retrospective review of the hospital records of patients receiving dental treatment under GA from 2006 until 2015 was performed. The patients were divided into three age groups: < 3 years, 3-6 years, and > 6 years. A range of information including basic patient characteristics and types of dental treatment was identified and then analyzed. RESULTS: A total of 791 cases (< 3 years old: 65 cases, 3-6 years old: 492, > 6 years old: 235; 549 male, 242 female) were treated under GA. The case number was found to have increased from 94 during 2006-2007 to 238 during 2014-2015, with the increase being especially pronounced among those aged 3-6 years (2006-2007: 49, 2014-2015: 165). The most common treatments (extraction, restoration, and pulp therapy) were associated with multiple dental caries (684, 86.4%). The < 3-years-old group was characterized by the highest decayed, extracted, and filled surface and decayed, missing, and filled surface indices; the highest mean number of treated teeth; and the highest mean number of treated teeth by composite resin fillings. The 3-6-years-old group had the highest number of primary teeth extractions. The > 6-years-old group had the lowest mean number of treated teeth by stainless-steel crowns (SSCs) and fewest cases treated with pulp therapy. From 2011 onwards, the number of primary tooth extractions significantly increased, while in 2013, there was a crossover whereby the SSC count surpassed the composite resin filling count. CONCLUSION: Over the past 10 years, there has been an increased use of GA for pediatric dental treatments, in particular, in cases with multiple dental caries. In addition, there has also been an increasing trend towards extraction of primary teeth and the use of SSCs.

Clinical evaluation of the timing of mesiodens removal.

BACKGROUND: Mesiodens is a common clinical finding among children and has a higher prevalence in Asian populations. The timing of the removal of mesiodens remains controversial. Clinical studies comparing early versus late removal are lacking. The aim of this retrospective study was to evaluate the frequency of clinical complications regarding the timing of childhood mesiodens removal and to explore the factors associated with complications following mesiodens removal. METHODS: In total, 384 Taiwanese children diagnosed with unerupted mesiodens who had attended the Pediatric Dentistry Department, Taipei Veteran General Hospital, Taipei, Taiwan from 2005 to 2012 were identified as potential participants. Among these patients, 105 children had received surgical odontectomy of the mesiodens under general anesthesia and had complete longitudinal clinical and radiographic follow-up records, including computed tomography (CT) evaluations; these patients were enrolled. The influence of age, the developmental stage of the adjacent permanent teeth, and the location of the mesiodens were explored regarding complications that were noted at the time of surgery, injury to the adjacent permanent teeth during surgical intervention, and the need for orthodontic treatment after surgery. RESULTS: The 105 children enrolled had 145 mesiodens. Removal of the mesiodens before the child was 5 years of age or 1/3 root-completed was associated with fewer complications at the time of surgery and a reduced need for orthodontic treatment after surgery. However, no significant difference was noted between the different groups in terms of surgical injury to the adjacent permanent teeth. CONCLUSION: The early removal of an unerupted mesiodens before the age of 5 years would seem to reduce complications and the need for orthodontic treatment. With the help of general anesthesia and evaluation by CT imaging, concerns regarding the child's cooperation and the possibility of damage to adjacent permanent teeth during early surgical intervention can be minimized.

Voltage generation of piezoelectric cantilevers by laser heating.

Converting ambient thermal energy into electricity is of great interest in harvesting energy from the environment. Piezoelectric cantilevers have previously been shown to be an effective biosensor and a tool for elasticity mapping. Here we show that a single piezoelectric (lead-zirconate titanate (PZT)) layer cantilever can be used to convert heat to electricity through pyroelectric effect. Furthermore, piezoelectric-metal (PZT-Ti) bi-layer cantilever showed an enhanced induced voltage over the single PZT layer alone due to the additional piezoelectric effect. This type of device can be a way for converting heat energy into electricity.

Single ZnO nanowire-PZT optothermal field effect transistors.

A new type of pyroelectric field effect transistor based on a composite consisting of single zinc oxide nanowire and lead zirconate titanate (ZnO NW-PZT) has been developed. Under infrared (IR) laser illumination, the transconductance of the ZnO NW can be modulated by optothermal gating. The drain current can be increased or decreased by IR illumination depending on the polarization orientation of the Pb(Zr(0.3)Ti(0.7))O(3) (PZT) substrate. Furthermore, by combining the photocurrent behavior in the UV range and the optothermal gating effect in the IR range, the wide spectrum of response of current by light offers a variety of opportunities for nanoscale optoelectronic devices.