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The use of computed tomography (CT) for craniofacial measurements is common in medical imaging, but concerns about accuracy and reliability persist, especially with different CT technologies. This study assessed the accuracy of twenty-six common measurements on consecutive CT images from the same patients, using multidetector CT (MDCT) and cone-beam CT (CBCT) with two software programs (Amira and Dolphin). Ten adult subjects with consecutive CBCT scans within one year were randomly selected. Another ten subjects with consecutive MDCT scans were paired with the CBCT group based on age, gender, race, occlusion, and craniofacial pattern. All digital imaging and communications in medicine (DICOM) files were randomly coded and analyzed using the two software programs. Intra-examiner reliability was assessed using the intraclass correlation coefficient. Successive measurement errors from consecutive scans for both imaging modalities and software programs were compared. For most skeletal linear and angular measurements, Dolphin showed greater successive measurement errors compared to Amira. Eight of the 26 common measurements had errors greater than one unit (millimeter or degree). Despite almost perfect intra-examiner reliability for upper airway analysis, average successive measurement errors were notably high, particularly for intraoral and oropharyngeal airway volumes. The successive Dolphin measurement error for oropharyngeal airway volume on CBCT images was over three times that on MDCT images. Given the substantial successive measurement errors observed during consecutive CT scanning for the upper airway, this study does not support the quantitative use of CT for analyzing changes in airway dimensions for research purposes. [ABSTRACT FROM AUTHOR]

Post-extraction alveolar ridge resorption is a common sequela when missing mandibular molar spaces are not managed in a timely fashion. The situation becomes more complicated in patients who seek orthodontic treatment if closure of the edentulous space is the major objective in order to avoid prosthetic rehabilitation. In the present article, two cases are reported, in which different bone augmentation graft materials were used and treatment duration and post-orthodontic alveolar ridge characteristics were compared. A regional acceleratory phenomenon after the grafting procedure facilitated uneventful orthodontic space closure. The status of the investing alveolar bone was compared using post-treatment cone-beam computed tomography. Both autogenous bone graft and allograft ridge augmentation procedures aided in successful molar protraction through the resorbed mandibular alveolar ridge, as well as preventing periodontal attachment loss.

Under the impact of climate change, the world is facing various extreme weather challenges. Cities face higher frequency and severity of these challenges due to high population density and high levels of business and commerce activities. How to reduce disaster risk has become an important connotation of risk city governance. People’s attitudes toward disaster prevention can help reduce disaster risk and management efforts and reduce mortality and economic losses. Using a stratified random sampling method, this study selected 600 respondents from four different environmentally sensitive districts in Taipei to examine the relationships between their socio-economic backgrounds (age and residence duration) and flood preventive behavioral attitudes. The analyses of the Chi-squared test indicate that there is a high correlation between residents’ age and flood preventive behavioral attitudes, while a low correlation in different regions. There are moderate to low correlations between the prevention behavioral attitudes and age of the residents in Zhongshan and Wenshan districts with low natural vulnerability / low social vulnerability. The relationship between residence duration and flood prevention behavioral attitudes was only associated in districts with high natural vulnerability / high social vulnerability, while the respondents in other districts did not show correlation relationships. It is recommended to increase the residents’ flood prevention behavioral attitudes to encourage positive behavior in the reduction of flood risk in different areas and similar environments.

Globalization and population growth have put great pressure on the environment over the last few decades, and climate change has increased associated negative effects. Researchers examine the interactions between human and the environment. Among them, the relationship between place attachment and pro-environmental behavior has attracted particular research attention. However, few studies have addressed the relationships among flood risk perceptions, place attachment, and climate change coping behavior in a densely populated urban area. This study examines the effects of perceptions of climate change and flood risk on coping behavioral intention, and determines whether place attachment plays a mediating or moderating role therein in Taipei, the flood-prone capital city of Taiwan. A total of 1208 questionnaires were collected. An analysis of the mediation effects based on a three-level regression model (Phase I) suggested that place attachment is not a mediator. Adjustment of the model and analysis of moderation effects using structural equation modeling (Phase II) suggested no moderation effect. In Phase III, the mediation effect was reexamined, with the replacement of dependent variables (adaptation/mitigation) with high-effort/low-effort coping behaviors, and one dimension of place attachment was replaced with four dimensions thereof (place dependence and place identity, place satisfaction, place affect, place social bonding). The results thus obtained reveal that the paths of place satisfaction exhibit significant mediating effects between attitudes and high-effort coping behavior. Some paths exhibit significant mediating effects between perceptions and low-effort coping behavior through place satisfaction. Another four paths exhibit partial significant mediating effects through place dependence and place identity and place social bonding. These results suggest that affective attachment of people to local places results in a behavioral tendency to protect or improve those places. The main contribution of this study is its support of meta-analyses of the effects of each dimension of place attachment to provide a better understanding of the effects of place attachment on flood risk perception and coping behavior. [ABSTRACT FROM AUTHOR]

Objectives: To compare the intra- and inter-examiner reliability of multidetector computed tomography (MDCT) and cone-beam computed tomography (CBCT) using Amira and Dolphin software analyses for craniofacial/airway measurements by six examiners., Materials and Methods: Five adults and one dry skull with CBCT and MDCT scan files were duplicated and randomly numbered. Six orthodontic residents imported these files into two software programs, oriented the images, set thresholds, and performed 26 measurements. Intra- and inter-examiner reliabilities were determined by using intraclass correlation coefficient (ICC) and presented with scatterplots., Results: Variables including anterior nasal width, posterior nasal width, frontomaxillary suture right-to-left, inner nasal contour point right-to-left, and minimum cross-sectional area in the oropharynx showed "moderate" to "substantial" intra- or inter-examiner agreement. Amira provided relatively reliable airway assessment, while Dolphin showed standard deviations 10 to 30 times larger for volumetric airway measurements. MDCT scans significantly reduced airway volume/area measurements compared to CBCT, except for intraoral airway volume., Conclusions: Unreliable skeletal measurements and low reliability of Dolphin for airway analysis discourage using CT to quantitatively correlate changes in craniofacial structures with airway dimensions., (© 0000 by The EH Angle Education and Research Foundation, Inc.)