Effect of diabetes mellitus on total amount of bone resorption in the tissues under denture base bearing masticatory pressure

1999 Fiscal Year Final Research Report Summary

• Project/Area Number: 10671826
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: 補綴理工系歯学
• Research Institution: Okayama University
• Principal Investigator: SHIRAI Hajime Okayama University Dental School, Department of Removable Prosthodontics, Research Associate, 歯学部, 助手 (00263591)
• Co-Investigator(Kenkyū-buntansha): MORI Shingo Okayama University Dental School, Department of Removable Prosthodontics, Research Associate, 歯学部, 助手 (30252993) ; HARA Tetsuya Okayama University Dental School, Department of Removable Prosthodontics, Associate Professor, 歯学部・附属病院, 講師 (60238160) ; SATO Takashi Okayama University Dental School, Department of Removable Prosthodontics, Professor, 歯学部, 教授 (80034172)
• Project Period (FY): 1998 – 1999
• Keywords: Diabetes mellitus / Bone tissues under denture base / Masticatory pressure / Amount of bone resorption / Histomorphometry / Rat

Research Abstract

The effect of diabetes mellitus on-bone dynamics in denture supporting tissue has not been investigated enough. The purpose of this study was to investigate the effect of diabetes mellitus on bone resorption in the tissues under denture base bearing masticatory pressure by using bone histomorphometry.
Two-hundred and fifty streptozotocin-induced diabetic male rats (n=50X5 groups) of Wistar strain were used in this study. Denture base was applied to the molar region of the hard palate at 22 weeks of age. In loaded groups, the denture base were designed to load a masticatory pressure of 1.0, 10.0 or 20.0 kPa to the palate, respectively. In covering group, the denture base was designed to contact with the palate without any mechanical pressure. The non-denture-wearing group received no intentional treatment. The cleansing of the palate and removable denture base was carried out at 3 or 4 day intervals. Palatal tissue block was excised from 5 rats of each experimental group after the denture insertion at one week interval. The specimens were stained with Villanueva bone stain, embedded in methyl-methacrylate, and ground frontally to 50μm thickness. Eroded surface and osteoclast surface were calculated by using two-dimensional graphic analyzing system. Amount of bone resorption was calculated as (A)-(B) ; (A) Formed bone tissue during 12 weeks prior to the denture insertion in covering group, (B) Remained bone tissue after the end of bone resorption in each bone resorbed group at each experimental period.
Bone resorption was observed in 10.0 and 20.0 kPa groups until 6 weeks after the denture insertion, respectively. Total amount of bone resorption was 189±38μm in 10.0 kPa group and 266±27μm in 20.0 kPa group. Comparing these results with results in normal rats in same condition as this study, it is showed that diabetes mellitus prolongs the period of bone resorption and increases total amount of bone resorption.