Diagnosis and management of cracked tooth by quantitative light-induced fluorescence technology

The aim of this case report was to describe the process of diagnosis and treatment of a cracked tooth using quantitative light-induced fluorescence (QLF).

A 43-year-old male presented at our dental clinic with a complaint of cold pain in #17 tooth. A routine oral examination with radiography was performed for evaluation of the oral condition and treatment planning. Additionally, QLF image capture was performed using Qraycam and Qraypen (AIOBIO, Seoul, Republic of Korea), to collect white-light and fluorescence images. The #17 tooth was observed to have a crack line, showing red fluorescence, from the distal to mesial aspect on the occlusal surface. Even though there was no visible root fracture in the radiographic image, bone loss was observed. Therefore, we performed periodontal treatment. One month later, a root canal treatment was performed because the patient still complained of pain in the #17 tooth. During this treatment, one fluorescent image and one white light image set was captured with the Qraypen. A crack line showing red fluorescence was observed, while the line was not visible to the naked eye. After treatment, the patient has had no complaint related to this tooth for 3 years until today.

Clinically, use of QLF confirmed the presence of a crack before and during a root canal treatment. Therefore, it is postulated that the QLF technology could objectively facilitate the diagnosis and treatment of a cracked tooth.