Brusevold Ingvild Johnsen, Bie Thea Martine Granvoll, Baumgartner Christine Sophie, Das Runa, Espelid Ivar
Department of Paediatric Dentistry and Behavioural Science, Institute of Clinical Dentistry, Faculty of Dentistry, University of Oslo, Oslo, Norway; Department of Oral Biology, Faculty of Dentistry, University of Oslo, Oslo, Norway.
Department of Paediatric Dentistry and Behavioural Science, Institute of Clinical Dentistry, Faculty of Dentistry, University of Oslo, Oslo, Norway.
Oral Surg Oral Med Oral Pathol Oral Radiol. 2017 Jul;124(1):52-61. doi: 10.1016/j.oooo.2017.03.050. Epub 2017 Apr 4.
The term molar-incisor malformation (MIM) has recently been presented in the scientific literature, where it is described as a condition with localized impaired root development. Here we present 6 recently discovered cases referred to our departments.
The patients were enrolled in the study after referral and were examined clinically and radiologically. Two extracted teeth were further examined with micro-computed tomography or microscopy.
Affected teeth were first permanent molars with hypoplastic roots, narrow pulp chambers, and a hypercalcified dentine layer cervical to the pulp chamber. Two of the cases also had cervical constrictions on the upper incisors. The patients were 8 to 12 years of age and healthy, but had experienced serious medical conditions of the head and neck region in their first year of life. Some of the cases had been referred because of acute infection and pain.
In 5 out of 6 patients, severe health problems in the head and neck region early in life may have been associated with root malformation in molars and incisors. Patients with MIM need to be followed closely, and extractions should be planned at the right time to avoid unnecessary infection and pain in addition to orthodontic problems.
磨牙-切牙畸形（MIM）这一术语最近出现在科学文献中，被描述为一种局部牙根发育受损的病症。在此，我们介绍最近转诊至我们科室的6例病例。
患者经转诊后纳入本研究，并接受临床和影像学检查。对两颗拔除的牙齿进一步进行显微计算机断层扫描或显微镜检查。
患牙为第一恒磨牙，牙根发育不全，髓腔狭窄，髓腔颈部有钙化过度的牙本质层。其中2例患者的上颌切牙也有颈部缩窄。患者年龄在8至12岁之间，身体健康，但在出生后第一年曾患有严重的头颈部疾病。部分病例因急性感染和疼痛前来就诊。
6例患者中有5例在生命早期出现的严重头颈部健康问题可能与磨牙和切牙的牙根畸形有关。MIM患者需要密切随访，除正畸问题外，应在合适的时间安排拔牙，以避免不必要的感染和疼痛。
