What occurs if an unbiodegradable object entered your lungs?

Depends on size...: If an object entered the lung, it might obstruct a bronchus (air tube). An object the size of a dime could do that. This might restrict airflow to that segment of lung, and might set the patient up for impacted mucus and post obstructive pneumonia. Very small particles could pass into the peripheral lung, and the body would attempt to wall these off by an inflammatory response and fibrosis.