Periapical osteosclerosis represents a localized increase in bone density around the apex of a tooth in response to low-grade pulpal irritation. This condition indicates host resistance to pulpal irritation, where the bone reacts by excessive formation rather than destruction. Unlike inflammatory lesions, there is no bone resorption, pus formation, or tooth mobility. The sclerotic bone is typically asymptomatic and discovered incidentally on radiographs, reflecting the body's attempt to reinforce and protect the area. Recognizing this helps avoid misdiagnosis and unnecessary treatment.

Reference: Oral Pathology, Neville et al., 4th Edition.