Blood Gas Tension and Acidity Level of Caries Exposed Vital Pulps in Primary Molars

Objective: The purpose of this study was to determine if gas tension and acidity levels could serve as biomarkers of pulp inflammatory status in primary dentition. Study design: The present study evaluated acidity level and blood partial pressures of O₂ and CO₂ collected from vital pulp chambers of 84 primary molars with deep carious lesions encroaching the pulp. Teeth were treated with pulpotomy or pulpectomy based on clinical judgement. Pulpectomy was performed when symptoms of spontaneous pain, difficulty in obtaining hemostasis and/or dark purple blood were present. Using a glass capillary, pulp chamber bleeding was collected and within ten minutes a neonate Astrup test was performed to determine blood gas module pH, pCO₂, and pO₂. Results: Eighty-four children with one affected tooth participated in the study (37 girls and 47 boys). Age ranged between 3.5 to 9-years (average: 5.3 years). Seventy-one (84%) were treated with the aid of inhalation analgesia, conscious sedation or general anesthesia. Pulpotomy was performed on 58 teeth (69%). Teeth undergoing pulpectomy revealed significant higher level of CO₂ partial pressure (P= 0.002). Acidity level values (pH) were also lower but none significantly in teeth with pulpectomy (P= 0.137). Conclusions: Higher pCO₂ levels was found in pulps needing pulpectomy.