The purpose of this study was to investigate whether dental injury diagnoses may predict adverse outcomes occurring 102 weeks after trauma, and to evaluate whether the severity of adverse outcome is related to laser Doppler flowmetry (LDF) measurements of blood flow from teeth. In 309 trauma patients, 404 permanent maxillary incisors and the respective contralateral homologous control teeth were investigated clinically and radiographically, and by LDF to assess local blood flow values. Dental displacement injuries were classified as grade I (subluxation), grade II (lateral or extrusive luxation), and grade III (avulsion or intrusive luxation). Dental fracture injuries were classified as uncomplicated crown fractures, complicated crown fractures, and root fracture. An adverse outcome was defined as the presence of ‘periapical radiolucency and/or grey discolouration’. Significant increase in risk of an adverse outcome occurred with a grade II dental displacement injury (15·07 odds ratio; P = 0·000), a grade III dental displacement injury (28·33 odds ratio; P = 0·000), and a root fracture (106·25 odds ratio; P = 0·000). Blood flow measurements that were significantly associated with more severe outcome were blood flow levels of ≤3 perfusion units (PU; 170·72 odds ratio; P = 0·000), and those of >3 PU and ≤6 PU (76·71 odds ratio; P = 0·000). Diagnoses of displaced and root fractured teeth predicted dental injury patients who went on to show adverse treatment outcomes of splinting. Blood flow measurements from teeth were related to the severity of adverse outcome.