What happens when oxygen gas is used into the filament bulbs?

When oxygen gas is used into the filament bulbs then tungsten metal melts and gets destroyed due to oxidation between tungsten and oxygen. 

A light bulb full of oxygen would not work well, as the bulb's tungsten filament, if it ignited at all, would burn very brightly and short out quickly. Oxygen is flammable, a decided fire hazard that would ignite the bulb's insides.

In the presence of oxygen, the filament would burn up as a result of the high temperature. ... The presence of an inert gas, such as Argon, actually inhibits this deterioration, allowing higher filament temperatures and brighter light bulbs.

In a bulb , nitrogen gas ( inert gas ) . is filled because in the bulb filament tungsten is there the melting point of tungsten in 3422°C and when electric city is passed it emits the light but doesn't melt .and the nitrogen gas is filled in the bulb so the bulb should not get burnt . if oxygen gas is filled instead of nitrogen gas then the fire can take place . therefore nitrogen gas is filled in the bulb.

If air were used in an electric bulb the filament, which becomes extremely hot when the light is on, would rapidly oxidize and burn out in seconds.

Instead the bulb is filled with argon, which is inert.

Thus oxygen is not dilled in filament bulb. Oxygen is not an inert gas unlike nitrogen and argon.