Water, better still soap and water, are pretty good at getting the crud out. A syringe, in a pinch a plastic bag with a small hole, is great for getting enough water pressure to get the dirt out. Get the dirt out and your well on your way to avoiding an infection.

I generally try to avoid sealing a laceration shut unless your quite sure the wound is clean. If there is any contamination your body is going to react. Puss, pain, swelling, redness, we have all seen the result. If the wound isn't sealed the body moves the contaminate, along with puss and other nasty stuff, to the surface where it flows out of the body. Seal a wound shut and there is a good chance the infection doesn't move out. Infections can move in and travel by way of blood vessels, lymph system and bone. Once they get into those systems they are much harder to fight.

The classic case is a deep puncture wound to a finger tip. The skin rapidly closes the wound off and the bone is just a few millimeters form the surface. If an infection gets into the bone your in trouble. People have lost an arm. A few their life.

In the field a stick to the finger tip is best washed out aggressively and forced to bleed if it isn't already. At the first sign of infection you dig down to the infection so it can drain and you irrigate and pack the area. If the infection gets into the bone your looking at expensive and risky treatments, like injecting antibiotics directly into the bone, or, the safer bet, amputation of the finger well above the site of the infection.

Lesson here is you don't want any infection to travel deep or get trapped in the body. A good way to make sure of this is to make sure that if there is any possible chance of an infection you give it way out that decreases the odds of it creating bigger problems.

With this in mind superglue is good, but possibly too good. It is easy to seal the laceration so well that a minor infection that would otherwise drain away and resolve could become a serious issue.

My preference is to keep the wound edges moist and loose edges of such a wound held in their approximate positions with Steri-strips for a day. If after 24 hours there is little redness or pain then seal it.

If you use superglue be very observant of any signs of infection and consider leaving a portion of the wound unsealed. At the first sign of infection cut through the superglue and drain the infection away. Follow by irrigation and packing until the infection clears.