PURPOSE: To assess the positional relationship between the maxillary sinus floor and the apex of the maxillary first molar using cone beam computed tomograph (CBCT). MATERIALS AND METHODS: CBCTs from 127 subjects were analysed. A total of 134 maxillary first molars were classified according to their vertical and horizontal positional relationship to the maxillary sinus floor and measured according to the distance between the maxillary sinus floor and the maxillary first molar. RESULTS: Type III (The root projected laterally on the sinus cavity but its apex is outside the sinus boundaries) was dominated between 10 and 19 years and type I (The root apex was not in contact with the cortical borders of the sinus) was dominated (P<0.05) between 20 and 72 years on the vertical relationship between the maxillary sinus floor and the apex of the maxillary first molar. The maxillary sinus floor was located more at the apex (78.2%) than at the furcation (21.3%) for the palatal root. The distance from the root apex to the maxillary sinus floor confined to type I was increased according to the ages (P<0.05). Type M (The maxillary sinus floor was located between the buccal and the palatal root) was most common (72.4%) on the horizontal relationship between the maxillary sinus floor and the apex of the maxillary first molar. CONCLUSION: CBCT can provide highly qualified images for the maxillary sinus floor and the root apex of the maxillary first molar.
Floors and Floorcoverings ; Maxillary Sinus ; Molar

OBJECTIVES: To challenge the problem of slipperiness, various slipmeters have been developed to assess slip hazard. The performance of in-situ slipmeter is, however, still unclear under the various floor conditions. The main objectives of this study were to evaluate the performance of three kinds of slipmeters under real conditions, and to find their dynamic and kinematic characteristics, which were compared with gait test results. METHODS: Four common restaurant floor materials were tested under five contaminants. Slipmeters and human gaits were measured by high speed camera and force plate to find and compare their dynamic and kinematic characteristics. RESULTS: The contact pressures and built-up ratio were below those of subjects. The sliding velocity of British Pendulum Tester was above those of subjects, while those of BOT-3000 and English XL were below those of subjects. From the three meters, the English XL showed the highest overall correlation coefficient (r = 0.964) between slip index and Ra, while the rest did not show statistical significance with surface roughness parameters (Ra, Rz). The English XL only showed statistical significance (p < 0.01) between slip index and contaminants. The static coefficient of friction obtained with the BOT-3000 showed good consistency and repeatability (CV < 0.1) as compared to the results for the BPT (CV > 0.2) and English XL (CV < 0.2). CONCLUSION: It is unclear whether surface roughness can be a reliable and objective indicator of the friction coefficient under real floor conditions, and the viscosity of contaminants can affect the friction coefficient of the same floors. Therefore, to evaluate slipperiness, the performance of the slipmeters needed to improve.
Floors and Floorcoverings ; Friction ; Gait ; Humans ; Restaurants ; Viscosity

PURPOSE: In an emergency, the quality of CPR prior to hospital arrival is a very important component for the survival of victims. We want to know differences in chest compression quality performed by groups that have variant experiences of CPR, and automatic CPR machine on the floor, or in an ambulance moving at 40 km/hr, or at 80 km/hr. METHODS: We analysed the chest compression quality of each group, and that performed on the floor, in an ambulance moving as 40 km/hr, and at 80 km/hr. We measured the following factors: mean compression depth; mean compression rate; exact performance percentile; and the compression error through too deep, too weak, wrong compression location, and no full recoil. RESULTS: In the student-nurse group, the quality of chest compression performed on the floor was better than that performed in a moving ambulance. In 119 member group, chest compression performed in an ambulance moving as 40 km/hr was better than that performed in an ambulance moving at 80 km/hr. The use of an automatic CPR machine, there were no differences in chest compression quality in all circumstances. In comparing each group, compression quality of the 119 member group and the automatic CPR machine group was better than that of the student nurses. CONCLUSION: In the group with real CPR experience, there were no differences between chest compression performed on the floor and that performed moving at 40 km/hr. Chest compression performed moving as 40 km/hr is better than that performed moving at 80km/hr. In the group without CPR experience, chest compression performed on the floor is better than that performed in a moving ambulance.
Ambulances ; Cardiopulmonary Resuscitation ; Emergencies ; Floors and Floorcoverings ; Humans ; Thorax ; Transportation of Patients

PURPOSE: The zygoma(Zygomaticomaxillary) complexes make up a large portion of the orbital floor and lateral orbital walls. Zygoma fracture frequently causes the posteromedial displacement of bone fragments, and the collapse or overlapping of internal orbital walls. This process consequently can lead to the orbital volume change. The reduction of zygoma in an anterolateral direction may influence on the potential bone defect area of the internal orbital walls. Thus we performed the quantitative analysis of orbital volume change in zygoma fracture before and after operation. METHODS: We conducted a retrospective study of preoperative and postoperative three-dimensional computed tomography scans in 39 patients with zygoma fractures who had not carried out orbital wall reconstruction. Orbital volume measurement was obtained through Aquarius Ver. 4.3.6 program and we compared the orbital volume change of injured orbit with that of the normal contralateral orbit. RESULTS: The average orbital volume of normal orbit was 19.68cm3. Before the operation, the average orbital volume of injured orbit was 18.42cm3. The difference of the orbital volume between the injured orbit and the normal orbit was 1.18cm3(6.01%) on average. After operation, the average orbital volume of injured orbit was 20.81cm3. The difference of the orbital volume between the injured orbit and the normal orbit was 1.17cm3(5.92%) on average. CONCLUSION: There are considerable volume changes in zygoma fracture which did not accompany internal orbital wall fracture before and after operation. Our study reflects the change of bony frame, also that of all parts of the orbital wall, in addition to the bony defect area of orbital floor, in an isolated zygoma fracture so that it evaluates orbital volume change more accurately. Thus, the measurement of orbital volume in isolated zygoma fractures helps predict the degree of enophthalmos and decide a surgical plan.
Displacement (Psychology) ; Enophthalmos ; Floors and Floorcoverings ; Humans ; Orbit ; Retrospective Studies ; Zygoma

In order to create a worker-friendly environment for institutional foodservice, facilities operating with a dry kitchen system have been recommended. This study was designed to compare the work safety and work environment of foodservice between wet and dry kitchen systems. Data were obtained using questionnaires with a target group of 303 staff at 57 foodservice operations. Dry kitchen facilities were constructed after 2006, which had a higher construction cost and more finishing floors with anti-slip tiles, and in which employees more wore non-slip footwear than wet kitchen (76.7%). The kitchen temperature and muscular pain were the most frequently reported employees' discomfort factors in the two systems, and, in the wet kitchen, "noise of kitchen" was also frequently reported as a discomfort. Dietitian and employees rated the less slippery and slip related incidents in dry kitchens than those of wet kitchen. Fryer area, ware-washing area, and plate waste table were the slippery areas and the causes were different between the functional areas. The risk for current leakage was rated significantly higher in wet kitchens by dietitians. In addition, the ware-washing area was found to be where employees felt the highest risk of electrical shock. Muscular pain (72.2%), arthritis (39.1%), hard-of-hearing (46.6%) and psychological stress (47.0%) were experienced by employees more than once a month, particularly in the wet kitchen. In conclusion, the dry kitchen system was found to be more efficient for food and work safety because of its superior design and well managed practices.
Arthritis ; Floors and Floorcoverings ; Surveys and Questionnaires ; Shock ; Stress, Psychological

The aim of this study was to present a method for endodontic management of a maxillary first molar with unusual C-shaped morphology of the buccal root verified by cone-beam computed tomography (CBCT) images. This rare anatomical variation was confirmed using CBCT, and nonsurgical endodontic treatment was performed by meticulous evaluation of the pulpal floor. Posttreatment image revealed 3 independent canals in the buccal root obturated efficiently to the accepted lengths in all 3 canals. Our study describes a unique C-shaped variation of the root canal system in a maxillary first molar, involving the 3 buccal canals. In addition, our study highlights the usefulness of CBCT imaging for accurate diagnosis and management of this unusual canal morphology.
Cone-Beam Computed Tomography ; Dental Pulp Cavity ; Floors and Floorcoverings ; Molar

This study was performed to analyze 6 day-term variations in bacterial communities contaminating the floor of two dry saunas that were operated at 64degrees C (low temp) and 76degrees C (high temp). Bacteria were sampled daily from the saunas for 6 days from Monday to Saturday. Genomic DNA was isolated directly from bacteria-collected cotton swabs. The diversity of the bacterial communities collected from the saunas was analyzed using thermal gradient gel electrophoresis (TGGE). The total numbers of DNA bands separated by TGGE for bacteria collected from the low temp and high temp sauna were 20 and 18, respectively, during the 6 days. Seven of 20 bacteria in the low temp sauna and eight of 18 bacteria in the high temp sauna were detected more than three times over the 6 experimental days. Twelve of the 26 bacterial genera contaminating the saunas were cross detected. Bacteria belonging to the genera Moraxella and Acinetobacter were selectively detected in the low temp sauna, whereas those belonging to Aquaspirillum, Chromobacterium, Aquabacterium, Gulbenkiania, Pelomonas, and Aquitalea were selectively detected in the high temp sauna. Three species of bacteria contaminating both the low and high temp saunas were thermophile or thermoduric. The results indicate that the sauna-contaminating bacteria may have been transferred from outside the saunas by user traffic but did not inhabit the saunas.
Acinetobacter ; Bacteria ; Chromobacterium ; DNA ; Electrophoresis ; Floors and Floorcoverings ; Moraxella ; Steam Bath

The purpose of this study was to examine profile of bacteria contaminated in a dry sauna. Bacteria sampled from the floor of the dry sauna (75~80degrees C) were separated and identified by using a thermal gradient gel electrophoresis (TGGE) technique, and were cultivated using a defined medium at 50degrees C. Bacteria grown in the defined medium were identified based on 16S-rDNA sequence homology. The band number of DNA separated by TGGE was 15, indicating the species diversity of bacteria contaminating the dry sauna. Seven species of bacteria were successfully cultured on agar plate medium at 50degrees C, which represented a combination of thermophilic and thermoduric bacteria contaminating the dry sauna. The highest limit temperature for growth of the bacterial isolates was generally 50degrees C when cultivated in a defined medium, but was raised to 60degrees C when cultivated in a complex medium. Consequently, the bacteria grown at 50~60degrees C are thermoduric or thermophilic, but others may not be.
Agar ; Bacteria ; DNA ; Electrophoresis ; Floors and Floorcoverings ; Sequence Homology ; Steam Bath

AIM: The aim of this study was to investigate the arterial arcade of maxillary sinus by determining the distance between the alveolar crest and the inferior border of the vessels in Korean population. MATERIALS AND METHODS: 76 patients and 87 available sinuses were determined by CT scan (Implagraphy, Vatech, Seoul, Korea). The distance between alveolar crest and inferior border of the vessel was determined considering the tooth area of posterior maxilla. RESULTS: The lowest distance was observed on first molar area and the average distance is 16.9 mm. DISCUSSIONS: it is important in sinus lift surgery that the vessels not to be damaged and that the anastomosis is situated in the lateral wall of maxillary sinus, which has to be exposed to gain access to the maxillary sinus. The knowledge of arterial arcade of maxillary sinus is important to perform the sinus floor elevation procedure effectively.
Floors and Floorcoverings ; Glycosaminoglycans ; Humans ; Maxilla ; Maxillary Sinus ; Molar ; Tooth ; Transplants

Lumbar hernia is an uncommon pathological defect of the abdominal wall. It presents difficulties in diagnosis and treatment because of the depth of the sac and the surrounding layers of muscle, fascia, and bone. It is an extrusion of intraperitoneal or extraperitoneal organs of the abdomen through a defect of the transversalis fascia. Inferior lumbar hernias are bordered by the iliac crest representing its base, limited by the external oblique muscle laterally, the latissimus dorsi medially, and the internal oblique muscle as its floor. Superior lumbar hernias are bordered by the 12th rib superiorly, quadratus lumborum muscle medially, and the internal oblique muscle laterally underneath the latissimus dorsi muscle. Diagnosis depends largely on the capacity for clinical suspicion, and confirmation is based on imaging tests. We report a case of an acquired primary lumbar hernia diagnosed by computed tomography, which was treated successfully at our institution.
Abdomen ; Abdominal Wall ; Fascia ; Floors and Floorcoverings ; Hernia ; Muscles ; Ribs