نوع مقاله: مقاله کامل پژوهشی

نویسنده

استادیار، دانشکده‌ی مهندسی پزشکی، دانشگاه صنعتی سهند، تبریز

10.22041/ijbme.2018.89324.1368

چکیده

با افزایش سن، نگرانی‏های بیش‌تری در رابطه با توانایی بافت‏های سخت مانند دندان در برآورده کردن نیاز‏های روزمره به مدت طولانی‏تر وجود دارد. ویژگی قابل توجه میکرو‏ساختار عاج دندان در وجود لوله‏های استوانه‏ای کوچک به نام لوله‏های عاجی است که تاثیر به‌سزایی در رفتار و خصوصیات مکانیکی از جمله مکانیک شکست آن دارد. افزایش سن منجر به پر شدن تدریجی لوله‏های عاجی می‏شود. در این مقاله با در نظر گرفتن میکروساختار عاج دندان به صورت مواد مرکب فیبری، به بررسی تاثیر میکروساختار و تاثیر تغییرات میکروساختاری ناشی از افزایش سن روی رفتار شکست و مسیر رشد ترک با استفاده از تئوری مکانیک شکست الاستیک خطی و روش تحلیل اجزای محدود پرداخته شده است. نتایج بیان‌گر آن است که مسیر رشد ترک علاوه بر هندسه‌ی ریزساختار عاج دندان، به خواص مواد اجزای سازنده‌ی آن و آرایش لوله‏های عاجی وابسته است. هم‌چنین نتایج ما نشان دهنده‌ی آن است که لوله‏های عاجی توپر ناشی از افزایش سن، نقش اساسی در مسیر رشد ترک ایفا می‌کنند و به عنوان دفع کننده‌ی رشد ترک محسوب می‌شوند.

کلیدواژه‌ها

موضوعات

عنوان مقاله [English]

Effect of Aging on Crack Propagation Trajectory in Dentin: Numerical Analysis

نویسنده [English]

  • Iman Zoljanahi Oskui

Assistant Professor, Faculty of Biomedical Engineering, Sahand University of Technology, Sahand New Town, Tabriz, Iran

چکیده [English]

With the increase in lifespan there are many concerns related to ability of the hard tissues such as teeth to meet the physical demands over an extended period of function. The dentin has a special microstructural feature that governs its mechanical behavior, e.g., fracture mechanics: cylindrical tubules that are called dentin tubules. These tubules are gradually occluded in the elderly. The present study is aimed to investigate the effects of microstructure and its aging-related changes of the considered fiber-reinforced composite dentin on the fracture behavior and crack propagation trajectory, utilizing linear elastic fracture mechanics and finite element method. Obtained results indicate that the crack propagation path depends on geometrical microstructure of the dentin as well as respective mechanical properties and arrangement of dentin tubules. Also our results delineate that occlusion of dentinal tubule due to the aging plays a significant role at crack propagation trajectory and behaves as a barrier to crack growth.

کلیدواژه‌ها [English]

  • Dental Microstructure
  • Aging
  • Linear Elastic Fracture Mechanics
  • finite element method

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