Department of Clinical Dentistry, Faculty of Health Sciences, UiT Arctic University of Norway, Tromsö, Norway.
Institute of Oral Biology, University of Oslo Faculty of Dentistry, Oslo, Norway.
Eur Arch Paediatr Dent. 2022 Feb;23(1):159-168. doi: 10.1007/s40368-021-00677-4. Epub 2021 Oct 29.
Identifying factors causing Molar-Incisor Hypomineralization (MIH) is an ongoing challenge. Preterm infants, routinely treated with antibiotics in cases of suspected sepsis, are more commonly affected by dental developmental defects. This study aimed to investigate the effects of gentamycin and ampicillin on the developing enamel in neonatal CD-1 mice in vivo.
Neonatal mice were randomized into a study (n = 36) and a control (n = 35) group. Antibiotics were injected intravenously for 4 days. All mice were sacrificed after 15-18 days. Micro-CT was used to analyse the mineral density (MD) of the enamel and the proportion of the enamel object volume (vol%) in first molars and incisors.
We demonstrated a significantly lower vol% enamel in the maxillary (30.9% vs. 32.7%; p = 0.004) and mandibular (32.5% vs. 34.6%; p = 0.015) molars in the study group than in the controls. The incisors were divided into segments upon analysis. We demonstrated both lower vol% and lower MD of the enamel in most segments in treated individuals compared to controls (p < 0.05).
The reduced MD and vol% in the molars and incisors are likely to have been caused by the antibiotics given during tooth development. The presented analysis of teeth in neonatal mice with micro-CT could be a valid model for further research on dental developmental defects.
确定导致恒切牙釉质发育不全（MIH）的因素是一个持续存在的挑战。早产儿在疑似败血症的情况下常规接受抗生素治疗，更容易受到牙齿发育缺陷的影响。本研究旨在研究庆大霉素和氨苄西林对新生 CD-1 小鼠体内发育釉质的影响。
将新生小鼠随机分为研究组（n=36）和对照组（n=35）。抗生素连续静脉注射 4 天。所有小鼠在 15-18 天后处死。微 CT 用于分析第一磨牙和切牙釉质的矿物质密度（MD）和釉质物体积比例（vol%）。
我们发现研究组上颌（30.9%对 32.7%；p=0.004）和下颌（32.5%对 34.6%；p=0.015）磨牙的 vol%釉质明显低于对照组。切牙在分析时被分为几个部分。与对照组相比，治疗组的大多数切牙部分的 vol%和 MD 都较低（p<0.05）。
在牙齿发育过程中给予抗生素可能导致磨牙和切牙的 MD 和 vol%降低。本研究通过微 CT 对新生小鼠牙齿的分析，可能为进一步研究牙齿发育缺陷提供有效的模型。
