following criteria were used to define a good interface: absence of voids between the different parts of the interface, uniformity of the hybrid layer, good opening of the tubuli orifices, and tag adherence to the tubuli walls. Morphological differences were found at the interface depending on dentin treatment and adhesive composition. The acetone-containing systems were associated with a continuous, gap-free hybrid layer that was linked intimately with the dentin. The tags adhered well to the tubuli walls and were often joined by side branches. In the water-based solvent systems, a lack of contact was visible between the resin tags and the tubuli walls, with some incompletely filled tubuli and some gaps in the hybrid layer. The 2 observational methods used, optical and scanning electron microscopy, proved to beSecond World War. At present, one in five people live in cities of over one million while nearly half live in cities of over 300,000. In May 2014, the Japan Policy Council (JPC) announced shocking results from a research study: if depopulation, aging, and youth outmigration to large cities continue at the present rate, approximately 30% of current local municipalities are in danger of vanishing by the year 2040. [1] Given that the number of women of child-bearing age in rural municipalities will fall by half between 2010 and 2040, those with current populations under 10,000 are considered to be in danger of disappearing. Small, regional cities, towns, and villages are where population decline and aging have the greatest impact. The Ministry of Land, Infrastructure, Transport and Tourism