OBJECTIVETo investigate clinical and imaging characteristics of delayed encephalopathy after carbon monoxide poisoning(DEACMP).

METHODSA retrospective and comparative analysis of neurological manifestations, course, periods of false-cure, prognosis and neuroimaging findings were conducted in 198 patients with DEACMP.

RESULTSOf these patients, 60.1% obtained an initial recovery within 30 d, 23.7% within 31-60 d and 14.6% over 60 d. Total clinical rate was 32.8%, and effectiveness rate 70.1%. According to imaging findings, 15.2% patients were found to have bilateral lesions of basal ganglion, and 70.0% with lesions of subcortical white matter, 12.6% with lesions of two types above mentioned and 2.1% with no lesions. The intervals between onset of illness and initial recovery were (44.6 +/- 10.1), (38.2 +/- 11.9), (61.3 +/- 17.0) d, and (7.5 +/- 2.4) d respectively. Imaging findings can demonstrate the severity of brain injury, but not necessarily parallel to the improvement of illness, for which SPECT proves more useful.

CONCLUSIONSDEACMP is involved in ischemic brain injury and a self-limited illness.

Brain Diseases ; etiology ; Carbon Monoxide Poisoning ; complications ; Humans ; Retrospective Studies ; Tomography, Emission-Computed, Single-Photon

Objective:To use a self-developed, prefabricated cap for making interocclusal records in implant-supported fixed prosthetic treatment, and to evaluate its effect of clinical application and accuracy of transferring intra-oral intercuspal position.Methods:Series of prefabricated caps for occlusal recording of implant-supported fixed prostheses were designed based on the healing abutments, and fabricated with three-dimensional (3D) printing. According to the inclusion and exclusion criteria, 12 partially edentulous patients who visited the Department of Prosthodontics, Peking University School and Hospital of Stomatology between November 2020 and September 2021, had lost no fewer than 2 contiguous teeth in distal extension (Kennedy Class Ⅰ or Ⅱ), and had received implant placement 3 months ago were enrolled. Self-control study design was used. Two occlusal records of each included case were obtained by the following 2methods:for the test group, appropriate prefabricated caps were used; and for the control group, polyvinyl siloxane occlusal record was directly set on the healing abutments. The working casts were mounted on the mechanical articulator using the 2 groups of occlusal records successively. Accuracy of occlusal relationship of the mounted casts was evaluated. Diagnostics test was performed to obtain the sensitivity and positive predictive value, which were determined in photographs by comparing the intra-oral occlusal contact points with those in the mounted casts, point-by-point. Virtual casts were taken by intraoral and extraoral scans in intercuspal position and imported to Geomagic Studio 2014. Then the root mean square values of occlusal clearance space between the upper and lower occlusal surfaces of remaining posterior teeth, and the deviations of the interocclusal position of the occlusal surfaces of the remaining teeth in the mandibular arches when superimposing the maxillary arches of the intraoral and extraoral scans were calculated. As a self-control design, paired t test was used. Results:Twelve participants were enrolled, including 3 men and 9 women aged (52.6±12.1) years, and 36 missing teeth. The prefabricated caps could fit on the healing abutments with good retention and stability. The sensitivity of the test group (0.73±0.14) was significantly better than that of control group (0.63±0.12, P<0.01), with no significant difference in positive predictive value between the 2 groups ( P>0.05). The deviations of the interocclusal position of the occlusal surfaces of the remaining teeth were (357.0±140.2) μm for the test group, and (399.4±206.3) μm for the control group, with no significant difference between them ( P>0.05). Conclusions:Interocclusal position record based on prefabricated cap in this study for implant-supported fixed prosthetic treatment can improve the consistency between the intra-oral occlusion and the occlusion in dental casts. This technique has good accuracy, clinical convenience and usability.