The usual application of intraoral syringe is for making impressions for bridge, etc.
The material is in two parts, one is the base material, the other is the catalyst or activator. First the two has to be mixed, usualy the catalyst is inserted into the cartridge of the base by a mixing tip. After mixing, also for a set length of time, the material is deposited into the impression tray and applied for a definite time, then removed.
The process has to be done quite precisely, because of the mixing and setting time are number of seconds, (well, can be minute-three or four minutes, depending of the actual material used) which has to be observed, partly for it to work, partly, because of dangerous materials.I think, this widely used application relates to your question.
The other application is for building up tooth core, which is a process replacing crowns in some cases.