ABSTRACT
Anastomotic leak is one of the most severe complications following right hemicolectomy but rarely happens, which should be diagnosed based on clinical manifestations, laboratory and radiographic examinations. Influencing factors of anastomotic leak after right hemicolectomy include bowel preparation, emergency surgery, anastomotic procedure (side-to-side anastomosis vs. end-to-side anastomosis, instrument anastomosis vs. manual technigue and intracorporeal vs. extracorporeal anastomosis), surgical resection range and patient's characteristics. The occurrence of anastomotic leak might be avoided by standardized operations and indocyanine green fluorescence imaging. Active treatment is recommended once anastomotic leak is diagnosed. Most patients can be cured by non-surgical treatments such as adequate drainage and anti-infection therapy. When severe sepsis happens or non-surgical treatment fails, surgical treatment should be carried out in time.
Subject(s)
Humans , Anastomosis, Surgical/adverse effects , Anastomotic Leak/surgery , Colectomy , Colon/surgery , Indocyanine GreenABSTRACT
OBJECTIVE@#To make more accurate occlusal quantitative analysis of three-dimensional (3D) virtual dental models and to compare the occlusal contact obtained by intraoral and dental cast scan.@*METHODS@#In this study, 5 subjects were intraoral scanned using laser scanner (3 shapes, Germany) to obtain the 3D virtual models of one tooth (the first molar), two teeth (the second premolar and the first molar), three teeth (the premolars and the first molar) and their opposite teeth, respectively. The silicone impressions were made and dental stone models were poured for each of them. The dental casts were scanned and then they were fixed to the maximum intercuspal position with a special locating jig for a rescanning of occlusal position. The virtual models taken intraorally and obtained with dental cast scan were introduced to a 3D quantitative analysis system, and some criteria regarding to occlusal contact were calculated and analyzed. The occlusal criteria were mean values of occlusal clearance space between the upper and lower occlusal surface (clearance), occlusal contact area (area), and cusp inclination (angle) of the mandibular first molar. Paired t tests were used to evaluate differences of occlusal criteria between the virtual models obtained with the intraoral scan and dental cast scan (α=0.05).@*RESULTS@#The mean values of occlusal clearance of one to three teeth obtained by way of intraoral scan were smaller than those obtained by way of cast scan by 0.134 mm, 0.177 mm, and 0.207 mm, respectively. While the occlusal contact areas were greater than the cast scan by 8.65 mm2, 10.28 mm2, and 11.46 mm2. No statistically significant differences were found between the cusps inclinations obtained with the two scanning methods, and the interclass correlations were high.@*CONCLUSION@#Occlusal clearance obtained by intraoral scan was less than that by cast scan while the occlusal contact area was greater than the latter, indicating that intraoral occlusal contact was closer. The difference of the standard deviations of occlusal clearance measured by the two methods were small and that of occlusal contact area was influenced by the number of teeth scanned intraorally. There was no statistical difference in cusp inclination between the two methods.
Subject(s)
Bicuspid/diagnostic imaging , Imaging, Three-Dimensional , Models, Dental , Radionuclide ImagingABSTRACT
OBJECTIVE@#To evaluate the wear intensity and surface roughness of occlusal veneers on premolars made of microhybrid composite resin or two kinds of ceramics in vitro after the thermocycling and cyclic mechanical loading tests.@*METHODS@#In the study,24 fresh extracted human premolars without root canal treatment were prepared (cusps reduction of 1.5 mm in thickness to simulate middle to severe tooth wear, the inclinations of cusps were 20°). The prepared teeth were restored with occlusal veneers made of three different materials: microhybrid composite, heat-pressed lithium disilicate ceramic and computer-aided design/computer-aided manufacturing (CAD/CAM) lithium disilicate ceramic in the thickness of 1.5 mm. The occlusal veneers were cemented with resin cement. The specimens were fatigued using the thermocycling and cyclic mechanical loading tests after being stored in water for 72 h. The wear of specimens was measured using gypsum replicas and 3D laser scanner before and after the thermocycling and cyclic mechanical loading tests and the mean lost distance (mm) was used to indicate the level of wear. The surfaces of occlusal contact area were observed and the surface roughness was recorded using 3D laser scanning confocal microscope before and after the fatigue test. Differences between the groups were compared using ONE-way ANOVA(P<0.05).@*RESULTS@#All the specimens successfully survived after the thermocycling and cyclic mechanical loading tests. The mean wear of microhybrid composite group, heat-pressed lithium disilicate ceramic group, and CAD/CAM lithium disilicate ceramic group was (-0.13±0.03) mm, (-0.05±0.01) mm and (-0.05±0.01) mm, the wear of microhybrid composite was significantly higher than the two ceramic groups(P<0.001).The mean surface roughness(Ra)before the fatigue test was(1.24±0.20) μm, (0.75±0.09) μm, (0.73±0.14) μm and it became (1.81±0.24) μm, (1.53±0.26) μm and (1.77±0.23) μm after the test . Before the fatigue test, the surface roughness of microhybrid composite was significantly higher than the two ceramic groups(P<0.001) and after the test, the surface roughness of heat-pressed lithium disilicate ceramic was significantly lower than microhybrid composite(P=0.005) and CAD/CAM lithium disilicate ceramic (P=0.010).@*CONCLUSION@#From the view of wear speed, microhybrid composite was significantly higher than the two kinds of ceramics, but it was similar to enamel when the opposing tooth was natural. The surface roughness before the themocycling and cyclic mechanical loading test of microhybrid composite was significantly higher than that of the two ceramic groups. After the test, the surface roughness of heat-pressed ceramic was significantly lower than that of the other two groups. From the view of surface roughness, heat-pressed ceramic has more advantage.