If a GP is found in a sinus tract but does not extend to the apex, what could be the diagnosis?

When a gingival pocket (GP) is found within a sinus tract and does not extend to the apex of the tooth, it suggests that the issue is likely related to the periodontal tissues rather than the pulpal or periapical structure of the tooth. A periodontal abscess occurs when there is an infection localized in the periodontal tissues, which can lead to the formation of a sinus tract that discharges pus to the surface of the gum.

The distinguishing factor here is that the sinus tract does not reach the apex, indicating that the problem is limited to the periodontal attachment rather than stemming from the pulp or root apex. This aligns with the characteristics of a periodontal abscess, where an infection can arise from periodontal disease, and purulent material can drain through gingival tissues, forming a pocket.

In contrast, other conditions listed, such as a dental abscess, often refer to broader situations that can include periapical involvement. A periapical granuloma typically connects directly to the apex of a tooth and would suggest pulpal involvement, often visible in radiographs. Pulp necrosis indicates that the pulp tissue is dead, usually associated with a more severe infection that would typically have a different clinical presentation, including a sinus tract extending to the apex.