The Analysis of Maxillary Sinus Aeration Dependent on Aging Process: Volume Assessment by Three Dimensional Reconstruction by High Resolutional CT Scanning / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: The purpose of this study was to evaluate the maxillary sinus volume in human depending on age and sex by using 3-dimensional reconstruction of computed tomography (3DR-CT). SUBJECTS AND METHOD: One hundred seventy three people (238 maxillary sinuses), who had taken paranasal sinus high resolution CT between December 2000 and November 2003, and had no evidence of inflammation or hypoplasia in CT finding, and had no specific history of surgery of paranasal sinus or maxillofacial trauma, were retrospectively analyzed. 3-dimensional reconstruction images were obtained using the surfacerendering technique with images by high-resolution CT on a personal computer. A software used for 3-dimensional reconstruction was Vwork 4.0 (CyberMedTM, Korea) used. The mean volume of maxillary sinus were evaluated in both sex. The ratio of maximal horizontal and half horizontal extension and the degree of descent of sinus below the nasal floor were evaluated. RESULTS: The development of maxillary sinus were found in males in their twenties and in teen females. The mean volume of maxillary sinus in an early adult were 24043 mm3 (Male) and 15859.5 mm3 (Female). There was a significant difference observed in the sinus volume (p<0.05) according to sex and the significant difference in the volume of maxillary sinus according to age groups between sex before reaching maximal volume. But there were no significant correlation among aging process, aeration of maxillay sinus after its maximal growth and the descent below the nasal floor. CONCLUSION: The growth of maxillary sinus is continued until the age of twenties in male and teens in female. Therefore, maxillay sinus operation affecting bony structures before those age may affect the sinus development; inferior meatal antrostomy also should be done after confirming the level of inferior extension of maxillary sinus below the nasal floor.

Development of Mastoid Air Cell System in Korean Normal Population: Three-Dimensional Reconstruction Based on Images from Computed Tomography / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Although there have been some reports that measured the size of the mastoid pneumatization, only a few studies have reported the age-related variations in the mastoid air cell system using three-dimensional (3D) reconstruction techniques of computed tomography (CT) images. This study presents that 3D reconstruction techniques of CT images can be used to measure the volume of mastoid pneumatization. In adddition, normal development of the mastoid air cell system in Koreans was evaluated. SUBJECTS AND METHOD: Retrospective study. A 3D reconstruction based on the image data obtained from CT was performed in the 205 ears of 105 patients without otologic diseases in order to measure the volume of mastoid pneumatization by a surface-rendering algorithm on a personal computer. RESULTS: The mastoid pneumatization continued to grow until the third decade. Thereafter, it declined slowly, and then rapidly after the seventh decade. The mean volume of mastoid pneumatization was 7095.2 mm3 in Korean adults. No statistically significant difference was found between males and females or between right and left sides. There was a significant difference between the larger and smaller sides of individuals. CONCLUSION: The volume measurement technique based on the 3D reconstruction technique reported here is widely available, highly accurate, and easy to perform. The results of this study may be helpful in evaluating the mastoid air cell system and for managing mastoid diseases.

A Comparative Study of the effects of Autogenous and Xenogenic Bone grafts with PRP(Platelet Rich Plasma) technique on Periodontal Regeneration / 대한치주과학회지

Regeneration of Periodontium with PRP does not only improve regeneration rate and density of bone but have a possibility to estimate faster healing process for soft tissue. And also, autogenous bone and xenogenic bone graft are effective on regeneration of periodontium. The purpose of this study is to evaluate the effectiveness of autogenous bone and xenogenic bone (BBP(R)) grafts with the PRP technique on regeneration of periodontium. 52 Generally healthy Pt. who had pocket depth 5mm at any of 6 surfaces of the teeth were in the study at Dept. of Perio. in Dankook Dental Hospital. Open Flap was treated for 18 infra-bony pockets as control group, autogenous bone with PRP was inserted for 25 infrabony pockets as first test group, and BBP(R) with PRP was inserted for 22 infrabony pockets as 2nd test group. Then evaluation was made after 3 and 6 months 1. There were significant differences between average probing pocket depth and clinical attachment level of 3, 6 months and minimal and maximal attachment level after 6 months each other. 2. There were significant differences in average probing pocket depth of control group and 2nd experimental group between 1 and 6 months. For clinical attachment level and minimal and maximal proving attachment level, there was a significant difference after 6 month of surgery. 3. There was no significant difference between two test groups for average probing depth, clinical attachment level, and minimal and maximal probing attachment level. As the result, PRP with bone graft could be very effective for regeneration of periodontium and there was no difference between xenogenic bone and autogenous bone.

Short-term Effects of Air Pollution on Hospital Visits for Respiratory Diseases in Seoul / 대한산업의학회지

Several studies have reported the associations between airborne particles and/or ozone and respiratory diseases. This study examined whether such an association could be seen in Seoul, one of the greatest city in Korea. We compiled daily records of hospital visits in Seoul from November 1, 1995 to October 31, 1996. The daily averages of ozone and particle matter whose diameter is 10 micrometer or less(PM10) from all monitoring stations were computed. Daily respiratory hospital visits were regressed on temperature, humidity, day of weak indicators, seasonal variation indicators, and air pollution. Each pollutant was first examined individually and then two pollutant models were fitted. RESULTS : Both PM10 and Ozone were associated with increased risk of respiratory hospital visits. The relative risk of respiratory hospital visits for 50 microgram/m3 increase in PM10(lagged 2 days) was 1.11(95% confidence interval: 1.05-1.18). The PM10 associations was insensitive to alternative methods of control for weather, including exclusion of extreme temperature days and control for temperature on another day. The ozone results were more sensitive to the approach for weather control. The relative risk of respiratory hospital visits for 0.01 ppm increase in O3 was 1.08(95% confidence interval 1.00-1.17). The magnitude of the PM10 effect in Seoul, where SO2 was essential present, was similar to that reported in the Europe and United states. In conclusion, The consistency of investigations of the health effects of air pollution suggest that attention should be paid to the control of air pollution.