Number of roots and canals in maxillary first premolars: study of an Andalusian population.

A study of 150 extracted maxillary first premolars from citizens of Seville, Andalusía, southern Spain, revealed 60 teeth with one root (40.0%), 85 teeth with two roots (56.7%) and five teeth with three roots (3.3%). The distribution of root canal shapes in the sample showed that all teeth with two or three roots had type I root canals (each canal had one apical foramen). Conversely, most of the single-rooted maxillary first premolars had root canal shape type II (two canals converging in the same apical foramen). Only 1.3% of the teeth had a unique orifice in the pulp chamber and only one root canal. These results emphasized the importance of good knowledge of the root canal morphology and the need for a careful radiographic examination as part of competent root canal therapy of maxillary first premolars.

Effect in vitro of Tifell (formocresol-eugenol) on macrophage adhesion.

The purpose of this study was to investigate the effect in vitro on macrophage adhesion of Tifell (formocresoleugenol), used as an intracanal medicament and in therapeutic pulpotomies in primary teeth, Macrophages were obtained from Wistar rats. As a test of macrophage phagocytic function the adherence capacity of macrophages to a plastic surface was determined. Assays were carried out in Eppendorf tubes after 15 min of incubation at 37 degrees C in a humidified atmosphere of 5% carbon dioxide. The adherence index (AI) was calculated. Results showed that Tifell decreased significantly (P < 0.05) the AI of macrophages. Half maximal inhibition of AI was obtained at 1:334.5 Tifell dilution (AI = 27.75; P < 0.05). Taking into account that substrate adherence is the first step in the phagocytic action of macrophages and in antigen presentation, Tifell could inhibit macrophage function and modulate immune and inflammatory responses in dental pulp and periapical tissues.

A case of combined dental development abnormalities: importance of a thorough examination.

This report describes a case of combined dental development abnormalities. A patient with a previous ectopically erupted supernumerary maxillary canine presented a new ectopically erupted supernumerary premaxillary tooth with dens invaginatus (Oehlers' type 2) and an aberrant coronal morphology, including a pit in the distal portion of the palatal surface. This tooth would have been diagnosed earlier if a panoramic radiograph had been taken at the first visit 5 months before. This case represents a good example of combined dental development abnormalities, i.e., a numerical anomaly (the supernumerary tooth), an alteration of dental position (the ectopic eruption), an alteration of dental morphology (the aberrant coronal shape), and the invagination. This case highlights the importance of a thorough examination, including complementary radiography, of patients with a dental anomaly.