Department of Orthodontics, College of Stomatology, Fourth Military Medical University, Xi'an, China; Department of Orthodontics, School of Dentistry, University of Washington, Seattle, WA, USA.
Orthod Craniofac Res. 2013 Nov;16(4):234-45. doi: 10.1111/ocr.12027. Epub 2013 Jul 22.
An earlier study revealed that the patterns of biomechanical loads on bones around the tongue altered significantly right after tongue volume reduction surgery. The current study was to examine whether these alterations persist or vanish over time post-surgery.
Five sibling pairs of 12-week-old Yucatan minipigs were used. For each pair, one had surgery reducing tongue volume by about 15% (reduction) while the other had same incisions without tissue removal (sham). All animals were raised for 4 weeks after surgery. Three rosette strain gauges were placed on the bone surfaces of pre-maxilla (PM), mandibular incisor (MI), and mandibular molar (MM); two single-element gauges were placed across the pre-maxilla-maxillar suture (PMS) and mandibular symphysis (MSP), and two pressure transducers were placed on the bone surfaces of hard palate (PAL) and mandibular body (MAN). These bone strains and pressures were recorded during natural mastication.
Overall amount of all loads increased significantly as compared to those in previous study in all animals. Instead of decreased loads in reduction animals as seen in that study, shear strains at PM, MI, and MM, tensile strains at PMS, and pressure at MAN were significantly higher in reduction than sham animals. Compared to the sham, strain dominance shifted at PM, MI, and MM and orientation of tensile strain altered at MI in reduction animals.
A healed volume-reduced tongue may change loading regime significantly by elevating loading and altering strain-dominant pattern and orientation on its surrounding structures, and these changes are more remarkable in mandibular than maxillary sites.
先前的研究表明，舌体缩小术后，舌周围骨骼的生物力学负荷模式发生了显著变化。本研究旨在探讨这些变化在术后是否会持续或消失。
使用了 5 对 12 周龄的尤卡坦小型猪作为研究对象。每对中，一只动物接受了约 15%舌体缩小手术（缩小组），而另一只动物则接受了相同的切口但不切除组织（假手术组）。所有动物在手术后均饲养 4 周。在前上颌骨（PM）、下颌切牙（MI）和下颌磨牙（MM）的骨表面上放置了 3 个玫瑰状应变计；在 PM 和上颌骨缝（PMS）以及下颌骨联合（MSP）上放置了 2 个单元素应变计；在硬腭（PAL）和下颌骨体（MAN）的骨表面上放置了 2 个压力传感器。在自然咀嚼过程中记录这些骨应变和压力。
与之前的研究相比，所有动物的所有负荷总量均显著增加。与之前研究中缩小组动物的负荷减少相反，缩小组动物的 PM、MI 和 MM 的剪切应变、PMS 的拉伸应变以及 MAN 的压力均显著高于假手术组。与假手术组相比，缩小组动物的 PM、MI 和 MM 的应变优势发生了变化，MI 的拉伸应变方向也发生了变化。
愈合的体积缩小的舌可能会通过增加负荷和改变其周围结构的应变主导模式和方向来显著改变负荷机制，并且这些变化在下颌骨部位比上颌骨部位更为显著。
