Physical properties of root cementum: Part 4. Quantitative analysis of the mineral composition of human premolar cementum

Background: The aim of this study was to perform a quantitative analysis of the calcium (Ca), phosphorus (P), and fluoride (F) concentrations in human first premolars. Methods: This study was conducted on 18 maxillary or mandibular first premolars that were collected from 16 prospective orthodontic patients (10 male, 6 female), mean age 13.9 years (range, 11.7-16.1 years), requiring first premolar extractions. After extraction, the teeth were prepared for electron probe microanalysis. The Ca, P, and F concentrations were measured on the buccal and lingual surfaces at the midpoint of the cervical, middle, and apical thirds of the root from the outer to middle to inner third of the cementum. Results and Conclusions: In first premolar cementum, there was significant interindividual variation in the Ca, P, and F concentrations (P = .024, .017, and .000, respectively). There was no significant difference in the Ca, P, and F concentrations of cementum between the buccal and lingual surfaces, except for a significantly higher F content at the cervical region on the buccal surface (P = .000). There was a decreasing gradient in the Ca, P, and F concentrations from the cervical to the apical third of the root, which was highly significant from the cervical to middle third (P = .000) and from the middle to apical third (P = .000), except for F, for which there was no significant difference from the cervical to the middle third on the lingual surface (P = .966). There was a significant increasing gradient in the Ca and P concentrations from the outer to inner third of cementum at the cervical (P < .01) and middle (P < .01) thirds of the root but no significant difference at the apical third of the root. For F, there was a significant decreasing gradient from the outer to the inner third of cementum at the cervical (P < .01), middle (P < .01) and apical (P < .01) thirds of the root.