A pilot study of a novel smartphone application for the estimation of sleep onset

The aim of the study was to investigate the accuracy of Sleep On Cue: a novel iPhone application that uses behavioural responses to auditory stimuli to estimate sleep onset. Twelve young adults underwent polysomnography recording while simultaneously using Sleep On Cue. Participants completed as many sleep‐onset trials as possible within a 2‐h period following their normal bedtime. On each trial, participants were awoken by the app following behavioural sleep onset. Then, after a short break of wakefulness, commenced the next trial. There was a high degree of correspondence between polysomnography‐determined sleep onset and Sleep On Cue behavioural sleep onset, r = 0.79, P < 0.001. On average, Sleep On Cue overestimated sleep‐onset latency by 3.17 min (SD = 3.04). When polysomnography sleep onset was defined as the beginning of N2 sleep, the discrepancy was reduced considerably (M = 0.81, SD = 1.96). The discrepancy between polysomnography and Sleep On Cue varied between individuals, which was potentially due to variations in auditory stimulus intensity. Further research is required to determine whether modifications to the stimulus intensity and behavioural response could improve the accuracy of the app. Nonetheless, Sleep On Cue is a viable option for estimating sleep onset and may be used to administer Intensive Sleep Retraining or facilitate power naps in the home environment.     

Neuromuscular adaptations in older males and females with knee osteoarthritis during weight-bearing force control

Background

Females exhibit significantly greater incidence, prevalence, and severity of osteoarthritis (OA) compared to males. Despite known biological, morphological, and functional differences between males and females, there has been little sex-related investigation into sex-specific biomechanical and neuromuscular responses to OA.

Philtrum length and intercommissural distance measurements at mixed dentition period

Anthropometric measurements of the lip and mouth are of great importance in clinical dysmorphology as well as reconstructive plastic surgery. In this study, the philtrum length (PhL) and intercommissural distance (ICmD) nomograms for Egyptian children in the mixed dentition period were established. A group of 1,338 Egyptian students in primary schools (735 boys and 603 girls) were included in the study. The students were at mixed dentition period and their ages ranged from 7 to 12 years. Anthropometric norms of PhL and ICmD were developed with significant sex difference in certain groups. A ratio between PhL and ICmD was developed. These data will help facilitate both objective and subjective evaluation of the lip and mouth for proper diagnosis of orofacial anomalies and variations as well as for ideal treatment plans.     

Acquisition of Anatomic Parameters Concerning Molar Pulp Chamber Landmarks Using Cone-beam Computed Tomography

Introduction

Cone-beam computed tomographic (CBCT) imaging is a valuable tool for endodontic therapy. The aim of this study was to verify whether clinical use of CBCT imaging can accurately acquire parameters concerning molar pulp chamber landmarks, which are important data to help start a successful access cavity and avoid iatrogenic furcation perforations.

Methods

Seventy CBCT images were used to measure 118 maxillary and 104 mandibular molars. The following vertical distances were measured: from the cusp tip/central fossa to the pulp chamber floor, to the pulp chamber ceiling, and to furcation; from the pulp chamber ceiling to furcation; from the pulp chamber floor to furcation; and the pulp chamber height. Measurements were read to the nearest 0.05 mm.

Results

The measurements were as follows: the pulp chamber floor to furcation (maxillary molar: 1.97 ± 0.58 [mean ± standard deviation, mm], mandibular molar: 2.24 ± 0.47), the pulp chamber ceiling to furcation (maxillary molar: 4.09 ± 0.68, mandibular molar: 3.78 ± 0.70), the central fossa to furcation (maxillary molar: 8.78 ± 0.79, mandibular molar: 8.53 ± 0.65), the central fossa to the pulp chamber floor (maxillary molar: 6.81 ± 0.83, mandibular molar: 6.29 ± 0.65), the central fossa to the pulp chamber ceiling (maxillary molar: 4.69 ± 0.59, mandibular molar: 4.75 ± 0.56); and pulp chamber height (maxillary molar: 2.12 ± 0.81, mandibular molar: 1.53 ± 0.68). Measurements showing the least standard deviation were the central fossa to furcation and the central fossa to the pulp chamber floor.

Conclusions

CBCT imaging may be used for precise clinical acquisition of the pulp chamber landmark measurements for molars thereby facilitating successful access cavity.     

Reliability and validity of measurements of facial swelling with a stereophotogrammetry optical three-dimensional scanner

Volume changes in facial morphology can be assessed using the 3dMD DSP400® stereo-optical 3-dimensional scanner, which uses visible light and has a short scanning time. Its reliability and validity have not to our knowledge been investigated for the assessment of facial swelling. Our aim therefore was to assess them for measuring changes in facial contour, in vivo and in vitro. Twenty-four healthy volunteers with and without an artificial swelling of the cheek were scanned, twice in the morning and twice in the afternoon (in vivo measurements). A mannequin head was scanned 4 times with and without various externally applied artificial swellings (in vitro measurements). The changes in facial contour caused by the artificial swelling were measured as the change in volume of the cheek (with and without artificial swelling in place) using 3dMD Vultus® software. In vivo and in vitro reliability expressed in intraclass correlations were 0.89 and 0.99, respectively. In vivo and in vitro repeatability coefficients were 5.9 and 1.3 ml, respectively. The scanner underestimated the volume by 1.2 ml (95% CI -0.9 to 3.4) in vivo and 0.2 ml (95% CI 0.02 to 0.4) in vitro.     

基于赝复体指导的义耳种植术前设计与修复

目的:探讨以赝复体为指导的义耳种植术前设计与修复.方法:采用螺旋CT对1名右侧先天性小耳畸形患者进行颅颌面三维重建,Geomagic软件中行虚拟残耳切除,获得种植导板并确定赝复体的位置.利用导板定位行残耳切除术及种植体植入术,制作卡杆附着体及树脂支架.采用三维光学扫描仪进行面部的三维成像,将CT数据和三维数据拟合,获得最终义耳赝复体的三维模型数据,通过选域激光烧结技术制作义耳蜡型,并翻制成硅胶义耳.结果:最终完成的义耳赝复体与种植修复前的赝复体形态位置完全一致,组织面与缺损区表面完全贴合,其形态、高度与对侧完全一致,患者对颜色、外观非常满意.结论:基于赝复体指导的义耳种植术前设计与修复是一种行之有效的办法和理念,值得在颜面部缺损赝复治疗中推广应用.     

Critique of the Dornier HM3 lithotripter as a clinical algesimeter

The power and nociceptive intensity of shock waves generated by the Dornier HM3 extracorporeal shock wave lithotripter (ESWL) are voltage dependent and suited to algesimetry in a controllable voltage range of 8–30 kV. Fidelity of the HM3 as an algesimeter was tested by:

1. (1) In vitro measurements of shock pressure at voltages between 14 and 30 kV were recorded by a force transducer at the point of clinical focus.

2. (2) Unanaesthetized volunteer (n = 5) assessment and VAS pain scores of shocks in the range of 10–24 kV, yielding highly significant correlations between blinded randomized shock voltage (r = 0.88), and VAS scores (r = 0.84).

3. (3) Voltage-tolerance curves generated from 33 ASA class 1 or 2 patients undergoing ESWL treatment under epidural analgesia with 0.125% bupivacaine, fortified with a bolus epidural dose of 100 μg fentanyl if pain arose during treatment. Voltage tolerance was increased by 50% after an epidural bolus of 100 μg fentanyl (P < 0.001). The respiratory consequences of epidural fentanyl were assessed by changes of respiratory rate and rhythm recorded from capnographic tracings of expired carbon dioxide.

This study indicates that the Dornier HM3 system provides a valuable opportunity to conduct precise, quantitative measurements of induced deep truncal pain, as well as the effectiveness and respiratory cost of analgesic interventions directly applicable to the safe management of acute pain.     

The effect of cuff pressure deflation rate on accuracy in indirect measurement of blood pressure with the auscultatory method

The importance of cuff deflation rate in the auscultatory method of measuring blood pressure was investigated using a computer-based model. To determine the relationship between the cuff deflation rate and the measurement error, two cuff deflation protocols were used, one based on heart rate (mm Hg per heartbeat), the other on a constant rate (mm Hg per second). The different deflation protocols and rates were tested using a constant blood pressure of 120/80 mm Hg and heart rates ranging from 40 to 120 beats/min. It was confirmed that a cuff deflation rate that is time based will introduce larger errors at low heart rates. Using heart rate as a basis for cuff deflation rate yields a constant error that is independent of heart rate. The currently used standard of 3 mm Hg/s could result in a maximum error of 2.5 mm Hg in both systolic and diastolic pressures at a heart rate of 72 beats/min. The maximum systolic and diastolic errors increase to more than 4 mm Hg at 40 beats/min. A deflation rate of 2 mm Hg/beat, however, yields a maximum error of 2 mm Hg for both systolic and diastolic pressures, independent of heart rate. A cuff deflation rate based on heart rate is recommended to help minimize changes in measurement error when measuring blood pressure if a wide range of heart rates will be encountered.Supported by grants from IVAC, San Diego, CA, and Physio Control, Redmond, WA.