This study analyzes the impact of a high-speed rail line on tax revenues and on the economy of affected regions within the country. The economic impact of infrastructure investment can be induced by changes in tax revenues when the infrastructure is in operation. Accurate regional GDP data are not necessarily available in many Asian countries. However, tax data can be collected. Therefore, this study uses tax revenue dates in order to estimate spillover effects of infrastructure investment. The Kyushu high-speed rail line was constructed in 1991 and was completed in 2003. In 2004, the rail line started operating from Kagoshima to Kumamoto. The entire line was opened in 2011. We estimated its impact in the Kyushu region of Japan by using the differencein- difference method, and compared the tax revenues of regions along the high-speed railway line with other regions that were not affected by the railway line. Our findings show a positive impact on the region’s tax revenue following the connection of the Kyushu rapid train with large cities, such as Osaka and Tokyo. Tax revenue in the region significantly increased during construction in 1991–2003, and dropped after the start of operations in 2004–2010. The rapid train’s impact on the neighboring prefectures of Kyushu is positive. However, in 2004–2013, its impact on tax revenue in places farther from the rapid train was observed to be lower. When the Kyushu railway line was connected to the existing high-speed railway line of Sanyo, the situation changed. The study finds statistically significant and economically growing impact on tax revenue after it was completed and connected to other large cities, such as Osaka and Tokyo. Tax revenues in the regions close to the high-speed train is higher than in adjacent regions. The difference-in-difference coefficient methods reveal that corporate tax revenue was lower than personal income tax revenue during construction. However, the difference in corporate tax revenues rose after connectivity with large cities was completed. Public–private partnership (PPP) has been promoted in many Asian countries. However, PPP-infrastructure in India failed in many cases due to the low rate of return from infrastructure investment. This study shows that an increase of tax revenues is significant in the case of the Kyushu rapid train in Japan. If half of the incremental tax revenues were returned to private investors in infrastructure, the rate of return from infrastructure investment would significantly rise for long period of time. It would attract stable and long-term private investors, such as pension funds and insurance funds into infrastructure investment. The last section of the paper will address how incremental tax revenues created by the spillover effects of infrastructure will improve the performance of private investors in infrastructure investment.

Introduction: In Colombia, the last oral health study showed that about 70% of the population has partial edentulism while 5.2% will have lost all their teeth between the age of 65 and 79. Rehabilitation with implants is an increasingly used option, which requires clinical and radiographic follow-up. Panoramic radiography is a low-cost option, in which it is possible to observe areas of bone loss, mesiodistal angulation of the implant, relationship with anatomical structures and lesions suggestive of peri-implantitis. Reports and analysis of relevant data on radiographic findings associated with dental implants are required to determine the risk factors for their success in patients who use them. Objective: To determine the prevalence and characterize the findings associated with osseointegration implants in panoramic radiographs. Methods: A descriptive cross-sectional observational study was carried out with 10,000 digital panoramic radiographs selected by convenience from radiological centers in the city of Bogota, Colombia, of which 543 corresponded to the sample analyzed for the presence of implants. The following were evaluated for each implant: location, position, angulation and distances to adjacent structures, using the Clínicalview® program (Orthopantomograph OP200D, Instrumentarium, USA). Results: The frequency of radiographs with implants was 5.43% with a total of 1,791 implants, with an average of 3.2 per radiograph. They were found in greater proportion in the upper jaw with a supracrestal location and an angulation of 10.3 degrees. 32% had implant/tooth or implant/implant distances that were less than optimal. 40.9% were restored and 1.2% showed lesions compatible with periimplantitis. Conclusions: A high percentage of the implants reviewed have a risk factor that affects their long-term viability, either due to angulation, supracrestal or crestal position, proximity to teeth or other implants, or because they are not restorable.

The temporomandibular joint (TMJ) is considered a bicondylar diarthrosis type joint. Imaging evaluation is a fundamental part of its assessment, which should include both bony and soft tissue characteristics and the relationship between them. Magnetic resonance imaging (MRI) represents the gold standard for the study of soft tissues; however, up to now, its main application continues to be the visualization of the articular disc. For this reason, the present article aimed to point out the information available in the literature regarding the visualization of the joint capsule in MRI and to evaluate it as an independent structure.

Objective: To evaluate the radiographic characteristics of dentigerous cysts (DC) diagnosed at the School of Stomatology of the Universidad Peruana Cayetano Heredia (UPCH) during the period of 2010–2017. Material and methods: Retrospective, descriptive, observational and cross-sectional study, where the panoramic radiographs of 37 cases of DC were selected. Results: The total number of diagnosed cases of dentigerous cysts was 233, which after inclusion and exclusion criteria, 37 cases were obtained, of which 45.9% of cysts were found in the second decade of life with a higher frequency of 51.4 percent for women, and a jaw predilection of 59.5% in all cases. In addition, it was found that 97.3% of the cases were radiolucent, defined limits were found in 67.6%, corticalized edges in 54.1% and unilocular in 94.6%. All dentigerous cysts were associated with a tooth, of which closed apex (48.6%) and tooth displacement (59.5%) were observed. The adjacent tooth was not affected in 56.8% of cases, but its hard lamina was affected (59.5%). The 68.2% of cases did not affect the basal mandibular cortex, but did displace the inferior dental canal (54.5%) and 46.7% of cases displaced the floor of the maxillary sinus. Conclusions: Most of the results obtained on the characteristics in the Peruvian population support previous studies reported in America, Europe and Asia. Radiographically the dentigerous cyst showed characteristics that support its clearly benign behavior.