Indeterminate dental pain: clinical characteristics and neurovascular compression; A retrospective case comparative study

Kiyokazu Iwawaki¹Motoko Watanabe^1*Yasuyuki Kimura¹Chizuko Maeda¹Chihiro Takao^1,2Risa Tominaga¹Takayuki Suga¹Trang Thi Huyen Tu^1,3Takahiko Nagamine^1,4Akira Toyofuku¹

• ¹Department of Psychosomatic Dentistry, Institute of Science Tokyo, Graduate School of Medical and Dental Sciences, Bunkyo-ku, Japan
• ²Division of Special Needs Dentistry and Orofacial Pain and Clinical Science, Tokyo Shika Daigaku, Chiyoda, Japan
• ³Department of Basic Dental Science, Faculty of Odonto-Stomatology, University of Medicine and Pharmacy at Ho Chi Minh City, Ho Chi Minh City, Vietnam
• ⁴Department of Psychiatric Internal Medicine, Sunlight Brain Research Center, Yamaguchi, Japan

Objective: Non-odontogenic toothache, which is characterized by tooth pain without corresponding dental abnormality, is occasionally indeterminate due to its complicated persistent teeth, dentoalveolar and/or facial pain, specifically between patients with persistent idiopathic dentoalveolar pain (PIDAP) and those with trigeminal neuralgia (TN), accompanied by atypical sensations. This study aimed to clarify clinical characteristics in this patient population and to identify clinical real-world factors for differentiation. Methods: All clinical data were retrospectively collected. Totally 340 patients, who were referred to our department with undiagnosed complicated persistent pain, were involved in the comparative analysis, depending on symptoms’ laterality, and 149 patients with unilateral symptoms were involved, depending on the presence of neurovascular compression (NVC) of trigeminal neurons and final diagnosis of PIDAP or TN. Results: Patients with bilateral symptoms (n = 105) presented more severe affected pain sensations with higher pain catastrophizing compared to patients with unilateral symptoms (n = 234, p = 0.022). NVC was observed in 84 patients (56.4%); however, no significant difference in clinical features was observed depending on the presence of NVC. While patients with TN (n = 26) presented significantly stronger "shooting" and "stabbing" pain (p = 0.004, p = 0.006, respectively) with more severe NVC condition (p = 0.033), patients with PIDAP (n = 123) showed significantly higher scores in the central sensitization inventory (p < 0.001) and somatic symptom scales-8 (p = 0.004). Conclusion: These results suggest that relying solely on examining the presence of NVC is insufficient to distinguish PIDAP and TN in this patient population, but careful assessment of pain quality, pain catastrophizing, central sensitization, and somatic symptoms, besides detailed neurovascular conditions, is crucial.