Pulp necrosis after orthognathic surgery. Patient came to the clinic complaining of darkening of the central incisor crown.
In Consolaro et al. Tooth darkening and pulp necrosis after orthognathic surgery: the laryngoscope and dental trauma. R Dental Press Ortodon Ortop Facial 16, v. 12, n. 5, p. 16-19, Sept/Oct. 2007.
Most studies on the effects of orthognathic surgery on dental pulp compare and emphasize that the effects are the same as those found in teeth subjected to dental trauma. These studies analyze cases where the
Le Fort I osteotomy was used, with or without segmentation, or mandibular osteotomy.
Still about the studies, the vast majority measured the pulp blood flow changes using laser Doppler flowmetry7 . Rarely were microscopic and imaging analyses methodologically well defined and unquestionable. Another methodology widely used was electrodiagnostics, to detect pulpal sensitivity.
The diagnostic precision and the practicality of laser Doppler pulpal flowmetry are questioned as the most adequate methodology for pulp viability analysis, considering that it was idealized for soft tissues. The presence of hard
tissue could compromise its effectiveness and accuracy of results. In the same way, results obtained only by pulp electrodiagnostics are questionable.
Some studies have been concerned with analyzing the occurrence of pulp necrosis, tooth darkening and internal resorption, regardless of whether in anterior or posterior teeth, but there is a concentration of attention on the upper central incisors.
Traumatized teeth can: a) maintain their pulp vitality; b) undergo aseptic pulp necrosis; c) undergo calcium metamorphosis of the pulp.
The aseptic pulp necrosis can gradually evolve to dental darkening and this clinical sign is an indication that something is happening to the carrier tooth. This sign can be noticed by the patient or the professional, or both, simultaneously. Calcific metamorphosis of the pulp has been well known clinically as obliteration of the chamber or root canal, commonly seen in traumatized teeth after a few weeks or months.
Calcific metamorphosis of the pulp occurs when trauma injures the vascular-nervous bundle, not enough to stop blood flow, but to restrict it. In these conditions of pulp suffering or intense cellular stress by hypoxia, the pulp cells undergo a metaplasia, i.e., change their phenotype and all fibroblasts, pe
ryocytes and reserve cells differentiate randomly into odontoblasts and, in a disorganized way, deposit a dysplastic dentin matrix in the extracellular medium, i.e. a poorly formed dentin, full of included cells, to the point that it is called osteodentin.
Calcific metamorphosis of the pulp may be simultaneous throughout the pulp, but it can be detected imagistically occurring from the walls to the center of the pulp, gradually reducing the pulp volume to the point where, in 6 to 12 months, the canal is completely obstructed or narrowed. Not rarely, pulp chamber obliteration and narrowing of the root canal occurs.
Pulp necrosis after orthognathic surgery.
