Feinberg S E, Weisbrode S E, Heintschel G
Department of Oral and Maxillofacial Surgery, Ohio State University College of Dentistry, Columbus 43210-1241.
Arch Oral Biol. 1989;34(12):975-84. doi: 10.1016/0003-9969(89)90055-1.
The effect of implanting calcium phosphate ceramics (CPC) into metabolically active sites within kitten mandibles during permanent premolar tooth eruption was examined. Forty kittens, 3-4 months of age were used: the deciduous second and third mandibular premolars were extracted and their sockets implanted with autologous blood clot, autogenous cancellous marrow, and the calcium phosphate ceramics, non-porous beta-tricalcium phosphate or porous hydroxylapatite. Animals were killed at 1, 2, 3, 4 and 5 months after implantation and undermineralized sagittal sections were evaluated by light microscopy. Eighty percent of hydroxylapatite implanted mandibles showed delay in tooth eruption concurrent with distortion in crown development, and a dense cellular fibro-proliferative response within the follicle of unerupted teeth. This response occurred in only one specimen with tricalcium phosphate, whereas normal eruptive patterns and crown development were routinely noted. Both the tricalcium phosphate and hydroxylapatite were integrated into the surrounding alveolar bone without evidence of an inflammatory response. Thus hydroxylapatite initiated a dense cellular fibrous network within the dental follicle preventing formation of an eruptive pathway, delaying tooth eruption and causing crown deformation. This was rarely seen with tricalcium phosphate, and may be due to the resorbability of tricalcium phosphate when compared to hydroxylapatite. Hydroxylapatite should therefore be used with caution for implanting into areas containing unerupted teeth with a metabolically active dental follicle.
研究了在小猫恒牙前磨牙萌出期间，将磷酸钙陶瓷（CPC）植入小猫下颌骨代谢活跃部位的效果。使用了40只3 - 4月龄的小猫：拔除乳下颌第二和第三前磨牙，其牙槽窝分别植入自体血凝块、自体松质骨髓以及磷酸钙陶瓷，即无孔β - 磷酸三钙或多孔羟基磷灰石。在植入后1、2、3、4和5个月处死动物，通过光学显微镜对未脱钙的矢状切片进行评估。80%植入羟基磷灰石的下颌骨显示出牙萌出延迟，同时牙冠发育出现扭曲，并且在未萌出牙的牙囊内有密集的细胞纤维增生反应。这种反应仅在一个植入磷酸三钙的标本中出现，而通常观察到的是正常的萌出模式和牙冠发育。磷酸三钙和羟基磷灰石均整合到周围的牙槽骨中，无炎症反应迹象。因此，羟基磷灰石在牙囊内引发了密集的细胞纤维网络，阻止了萌出通道的形成，延迟了牙齿萌出并导致牙冠变形。磷酸三钙很少出现这种情况，这可能是由于与羟基磷灰石相比，磷酸三钙具有可吸收性。因此，在将羟基磷灰石植入含有具有代谢活性牙囊的未萌出牙区域时应谨慎使用。
