The severity of pulpitis is a crucial factor in determining the suitable treatment. There are no clear objective indicators to assess the stage of pulp inflammation that could be used in clinical practice. The change in blood pH of the pulp during the inflammatory phase could hypothetically serve as an indicator of the pulp inflammation severity. The aim of this study was to assess the pH values in the pulpal blood of mature teeth in patients with symptomatic pulpitis, in comparison with the healthy controls. The study included patients with symptoms of pulpitis in premolar or molar teeth (Test group; n = 24, mean age 36.04, SD 7.10), and healthy controls (Control group, n = 6, mean age 24.5, SD 5.94) referred for extraction of premolars or third molars, for orthodontic reasons. The pulpal blood was taken at the opening of the endodontic access cavity, and the pH value was measured in both groups. Statistical analysis was performed using the SPSS 27.0 program with a significance level of p ≤ 0.05. The Mann–Whitney test for dependent samples was performed to evaluate the statistical difference between the groups. The patients with symptomatic pulpitis had significantly decreased pulpal blood pH compared to the healthy controls (p ≤ 0.05). The mean pulpal blood pH was 7.27 (SD 0.06) and 7.40 (SD 0.02) in Test and Control groups, respectively. In the Test group, the pulpal blood pH values were significantly lower in the patients who had symptoms for 3 days or more (7.25, SD 0.05) than in those who had symptoms for up to 3 days (7.33, SD 0.03) (p < 0.001). The pH value of the pulpal blood gradually declines in cases of symptomatic pulpitis, along with increasing duration of the symptoms.

The tooth impaction of the lower second premolars is an occasional condition but is still seen in clinical practice with a prevalence of 0.6–2.6%. The present case report describes a rare condition of the lower second premolar impaction. An 11-year-old female patient presented with the anteroposterior dental discrepancy, midline shift, and occlusal cant. Intraoral examination revealed the absence of the lower right second premolar with no space available for the eruption. X-ray examination revealed the impaction of tooth #45 in a vertical position, tilting of the adjacent teeth, and two-thirds root length development. The orthodontic treatment plan included space opening using a fixed appliance with a coil spring. The natural eruption of the tooth was expected according to dental age and root development. When the space was opened, no change in the position of tooth #45 was observed. Surgical exposure and active traction were performed. However, the intrusion and tilting of adjacent teeth were observed during the next appointments with no vertical change of tooth #45. Ankylosis was suspected as no tooth movement was recorded. The surgical luxation and osteotomy of the coronal alveolar bone of the impacted tooth were planned for the imminent forced eruption, which was expected due to the young age of the patient. Consequently, the crown of tooth #45 emerged and the bracket was placed. Further traction was planned to use a micro-screw. Following the traction, no vertical displacement of the tooth was observed in the subsequent appointments. Radiographic examination revealed radiolucency in the coronal third of the root. The patient was referred to the endodontist, and CBCT revealed external cervical root resorption in the late reparative stage. ECR in an impacted tooth, mimicking the manifestation of tooth ankylosis, can cause orthodontic treatment failure.