The experiment lasted 0.97 seconds but did not actually use deuterium or tritium fuels. The Japanese reactor, for example, reached a temperature of 190,000,000 K during the course of the experiment, according to Nature.
Containment is done using magnetic fields, but at a high cost in power.
Producing more power from the reaction than was used to create it is a significant milestone towards producing a workable reactor. The goal of scientists involved in fusion research is to use nuclear fuel in a sustained reaction. Nature notes that Japan is interpreting the results, however, to show that they are good candidates for hosting the International Thermonuclear Experimental Reactor, a multibillion dollar experiment proposed by Europe, Russia, the United States and Japan. The project is currently in the engineering design phase, which spans the years 1992-1998.