Final answer:
An incomplete tooth fracture, often associated with larger restorations, can lead to a dull, prolonged pain upon chewing and is more commonly found in supporting cusps. The fracture might not be easily identified without transillumination, even if x-rays reveal past restorations or cavities.
Step-by-step explanation:
An incomplete tooth fracture is often associated with medium to large-sized restorations and can result in a dull, prolonged pain on chewing. This type of discomfort and specific pain reaction is due to the movement of the fractured tooth segments during mastication which can irritate the pulp. Although some tooth decay and restorations can be visualized externally or with an x-ray, a fracture may not be readily diagnosed without additional methods such as transillumination, which uses light to detect fractures not obvious on radiographs.
Tooth anatomy, such as cusps and incisors, plays a role in where fractures are most likely to occur. For example, the supporting cusps, which bear the brunt of the force during chewing, are more commonly involved in fractures. In worse case scenarios, if the fracture is not identified and treated, the decay can extend into the pulp or even lead to infection spreading to the bloodstream, resulting in painful abscesses. It is essential for a dental health professional to be thorough in investigating symptoms of toothache and discomfort to prevent further complications and provide the appropriate treatment.