When it comes to the cleanliness of your digital or film equipment, it may be too hard to tell which is better. The photographer is largely responsible for keeping his/her equipment clean or storing it in the best environments; and dust is a constant issue for all types of photographers. With that said, digital single-lens reflex (DSLR) cameras are typically more prone to dust problems. With film cameras, the film is constantly advanced through the camera and minimizes the chance of dust lying on each frame. With digital cameras, the sensor (digital film) remains stationary at all times, making it more susceptible to dust, and has been a well noted problem for many digital photographers. This could become an even larger problem if the photographer is constantly changing out the lens in dusty environments. However, if you take extra care of your equipment and spend time cleaning it, the dust problem can be minimized for both film and digital.
With film cameras, because the back of the camera is opened everytime you load a roll of film, the back of the camera can be exposed to debris such as dust or dirt. There is the potential that the film can be scratched as the film is wound through the camera, and may damage the entire roll. For a long time, digital cameras remained only light tight and not sealed, allowing dust or dirt to get into the backs of the cameras. This can cause a problem equal to that of film cameras and may require professional equipment cleaning services. Some modern digital cameras are beginning to adapt dust and weather seals to avoid this problem altogether, but it still remains an issue in the majority of equipment available.
Regardless on your camera of choice, dust is a large problem and can be menacing to anyone. The best thing you can do is store your equipment is a dust-free environment, or at the very least, inside a protective camera bag. You will likely never be able to completely eliminate the dust threat, but you can certainly take proper steps to minimize it.