Aim of investigation: Persistent dento-alveolar pain disorder (PDAP) is the suggested new name of an enigmatic condition often described as atypical odontalgia, characterized by severe and continuous pain in the teeth and jaws and possibly associated with neuropathic pain mechanisms. In a recent 7-year prospective study, regression analysis found that neither unresponsiveness to peripheral lidocaine injection nor the presence of unspecified somatosensory abnormalities in the pain region could predict pain persistence in PDAP over time. The present study aimed to further explore the relationship between long-term outcome and (i) specified somatosensory abnormalities in the pain region and (ii) the responsiveness to peripheral lidocaine injection, both assessed at baseline. Methods: 43 patients diagnosed with PDAP were followed from 2002 (baseline) to 2009 (follow-up). The long-term outcome measure was overall improvement over time, measured by the 7-point Patient Global Impression of Change (PGIC) scale. The ratings ‘very much improved’ or ‘much improved’ were considered clinically relevant improvement. Quantitative sensory testing (QST) profiles included 9 measures assessing (i) thermal and mechanical function (normo-, hypo-, or hyperfunction), and (ii) signs of central sensitization (CS) (present/absent). Lidocaine injection in the pain area was double-blinded and placebo-controlled, and effective anesthesia was defined as ≥50% reduction in pain 30 min after administration. Descriptive statistics and logistic regressions analyzed the relationship between long-term outcome (PGIC), baseline patient somatosensory characteristics, and baseline lidocaine responsiveness. Results: Follow-up data were available for 37 patients, of which data on both QST profiles and responsiveness to lidocaine injection were available for 26 (70%). 8/26 patients (31%) experienced clinical improvement in their overall pain situation over time. 21/26 patients (81%) had at least one sensory abnormality. Stratified into subgroups, 9 patients (35%) had signs of CS only (represented by gain in windup ratio and/or dynamic mechanical allodynia to brush or vibration stimulus); 6 (23%) had CS + hypofunction in mechanical or thermal perception; 4 (15%) had CS + hyperfunction in mechanical and/or thermal perception and 2 (8%) displayed only hypofunction in mechanical and/or thermal perception. None of the subgroups were associated with overall improvement over 7 years (OR 0.250–0.875, P=0.317–0.923). Average pain before lidocaine injection was 41 mm VAS (SD 25). 30 minutes after injection, 12/26 patients (46%) experienced a ≥50% pain reduction. Effective pain relief from lidocaine was not associated with overall improvement over time (OR 1.25, P=0.793). When QST profiles and lidocaine responsiveness were combined, no possible combination could predict overall improvement (P=0.998–1.0). Conclusion: No predictive value for the long-term outcome of patients with PDAP was found for (i) somatosensory abnormalities revealed by QST, (ii) the responsiveness to peripheral lidocaine injection in the painful region, or (iii) the combination of these. The results should be interpreted with caution due to study design and relatively small sample size, but suggest that these parameters are not strongly associated with long-term outcome as measured by the PGIC instrument.