The influence of occlusal overload on the threshold of tooth pain.

Research Project

Project/Area Number	62570879
Research Category	Grant-in-Aid for General Scientific Research (C)
Allocation Type	Single-year Grants
Research Field	補綴理工系歯学
Research Institution	The University of Tokushima
Principal Investigator	KUBO Yoshihiro Assistant Professor of Fixed Prosthodontics, Sch.of Dent., 歯学部附属病院, 講師 (50136686)
Co-Investigator(Kenkyū-buntansha)	KONDOH Hisashi Instructor of Fixed Prosthodontics, Sch.of Dent., 歯学部附属病院, 助手 (60186856) HASHIKAWA Keiichi Instructor of Fixed Prosthodontics, Sch.of Dent., 歯学部附属病院, 助手 (60172847) NIIYA Yasushi Instructor of Fixed Prosthodontics, Sch.of Dent. IKEDA Takashi Instructor of Fixed Prosthodontics, Sch.of Dent. (30193204) 新谷泰司徳島大学, 歯学部・附属病院, 助手
Project Period (FY)	1987 – 1988
Project Status	Completed (Fiscal Year 1988)
Budget Amount *help	¥2,100,000 (Direct Cost: ¥2,100,000) Fiscal Year 1988: ¥500,000 (Direct Cost: ¥500,000) Fiscal Year 1987: ¥1,600,000 (Direct Cost: ¥1,600,000)
Keywords	occlusal overload / tooth sensation / tooth electrical stimulation / periodontal pulsation / 歯周脈波
Research Abstract	The hypersensitivity of a vital tooth caused by occlusal overload is found in dental practice, but this mechanism is an open question. In this research the influence of occlusal overload on tooth pulp as well as periodontal tissue was studied. A high inlay was placed in a tooth of a volunteer and the additional height was measured with IP-Checker. The threshold of tooth pain induced by electrical stimulation, the value of vertical tooth migration and the amplitude of periodontal pulsation were measured. The condition of occlusal contacts in a dental arch was recorded with an articulating paper before and agter the placement of a high inlay. The results are as follows: 1. 21 teeth studied, 16 decreased in the threshold of tooth pain, three increased and two did not show the characteristic change. 2. The decrease in the threshold of tooth pain might be due to reversible inflammation of the pulpal tissue, while the increase might be due to repetitive slight decrease of the pulpal blood stream or to pressure on the pulpal nerve at the apex of periodontal tissue. 3. The threshold changes of tooth pain had a significant relationship to the state of the vertical tooth migration and the amplitude of periodontal pulsation. 4. a high inlay sometimes induced the change in occlusal contacts throughout the dental arch even after the proper occlusal adjustment was done.