Lesion progression in post-treatment persistent endodontic lesions

By Yu V, Messer H, Shen L, Yee R, Hsu C

Date: 01/2014
Journal: JOE


Purpose: The aim of the study was to observe the radiographic and clinical progression of postendodontic persistent lesions and potential risk factors for lesions that did not improve.

N= 114 subject with 151 teeth with PA lesion still present after at least 4 years of root canal treatment.


•Dental records of patients who attended a university-based dental center were hand-searched to identify potential persistent endodontic lesions

•A widened periodontal ligament space with discontinuity of the lamina dura or a larger radiolucency associated with any root of a root-filled tooth at least 4 years after treatment was considered a persistent lesion.

•Clinical examination: pain history (using survey confirmed from the dental chart), pain at appointment (percussion, palpation). Symptoms were recorded as present if patient has moderate to sever pain. Coronal restoration was assessed.

•RG examination : was assessed by 2 calibrated examiners for each root filling (length and homogeneity), restoration (marginal integrity), iatrogenic errors . also, difference in size and shape .(size measured using plastic ruler). (cone positioning device was used to take recall RG).

Most highlighted Results:

•Factors associated with lesion progression:

•Lesions that had persisted for a longer period appeared less likely to be improving

•Pretreatment lesion size: Small lesions at the time of treatment (appearing as widened periodontal ligament space of <1.9 mm) most commonly showed deterioration (55.3%) or remained unchanged. A substantial majority of larger lesions (2-mm diameter and greater) had reduced in size since treatment.

•Recall lesion size > 5 mm in diameter posed the highest relative risk .

•root-filling length showed a significant association with lesion progression.

•Pain on biting, post obturation flare up were associated with higher risk of lesion progression.

Clinical significance

A specific interval alone should not be used to conclude that a lesion will not resolve without intervention. Asymptomatic lesions should be monitored further, especially if the lesion has reduced in size since treatment.