A digital pen-based application form filling system with a modification prevention function, which eliminates a possibility that digital information initially written in digital paper using a digital pen may be modified deliberately or accidentally. The switching device has an address storage circuit for storing address information of a defective memory cell and detecting whether or not selected memory cells include a defective memory cell, a data storage circuit for storing replacement data for memory cells including a defective memory cell, and a switching circuit. Each bracket is bonded to the facial surface of a tooth in the arch. Additionally, the electrodes are positioned such that providing electrical contact is eased. The very smooth surface A or D is suitable in particular for coating with materials, for example SiOx, by means of plasma polymerization of hexamethyldisiloxane by the CVD or PECVD method, which provides the film with a high oxygen barrier and is suitable in particular as packaging for light- and air-sensitive foods or other consumable items. The light bulbs are mounted in a heat absorbing plate and light dispersing dichroic lenses are mounted above selected light bulbs.