Histologic evaluation and immunohistochemical localization of STRO-1 and BMP-4 in rat immature teeth: A comparison between vital and induced pulp necrosis

AbstractObjective ess histological features and the expression of STRO-1 and BMP-4 in dental pulp and periapical tissues in vital or necrotic rat immature teeth. wer left first molars of male Wistar rats ageing four weeks (n = 24) had their pulps exposed to the oral environment for 3, 6, 9 and 12 weeks (animals ageing 7, 10, 13 and 16 weeks-old, respectively; n = 24). The right lower first molars served as control untouched teeth. After sample harvesting the jaws were dissected and processed for histology and immunodetection of STRO-1 and BMP-4. s ic teeth had root development arrested, while control animals showed development of dental tissues. Immunohistochemistry showed that detection of BMP-4 was restricted to vital pulps. For both groups, STRO-1 expression was evident around blood vessels walls. Neither BMP-4 nor STRO-1 was observed in the apical papilla region. sion -positive precursor cells were not detected in the apical papilla. BMP-4 expression has not been detected during infection.