The superstructure desing of a newly developed one-stage zirconia implant

1993 Fiscal Year Final Research Report Summary

• Project/Area Number: 03454448
• Research Category: Grant-in-Aid for General Scientific Research (B)
• Allocation Type: Single-year Grants
• Research Field: 補綴理工系歯学
• Research Institution: HIROSHIMA UNIVERSITY
• Principal Investigator: SATO Yuji Hiroshima Univ.Sch.of Dentistry Research assistant, 歯学部, 助手 (70187251)
• Co-Investigator(Kenkyū-buntansha): SAGARA Masaki Hiroshima Univ.Sch.of Dentistry Research assistant, 歯学部・附属病院, 助手 (10253098) ; HASHIMOTO Masaki Hiroshima Univ.Sch.of Dentistry Assistant Professor, 歯学部・附属病院, 講師 (80189505)
• Project Period (FY): 1991 – 1993
• Keywords: One-stage / zirconia / Dental implant / Superstructure

Research Abstract

The purpose of this study was to examine effects of superstructure designs on bony interface of a newly developed one-stage zirconia implant, and to present useful informations on the superstructure design of one-stage zirconia implant. Two zirconia implants were placed by tapping insertion into the prepared bone socket at left and right sides of molar and premolar edentulous areas of the mandible of each of seven female adalt monkeys (Macaca fuscata). Three months after implant placement, three kinds of metal superstructure were cemented on the implants. The implants were divided into 3 groups according to superstructure designs. In group 1 (Gl), a single metal crown was cemented on the reight mesial implant. In group 2 (G2), a metal bridge was cemented connecting left two implants. In group 3(G3), a metal bridge was cemented connecting right distal implant and neighboring second molar. After 12 months and 24 months of loading, the animals were sacrificed and undecalcified sections involved implants were prepared and examined by light microscopy. Histomorphometric analyzes were also performed. Histologically, direct bone-implant interface was generally achieved in all implants, and there was no clear difference among three groups. In histomorphometric analyzes of a 12-month study, bone contact ratio of the implant in G1 was lower than others. However, in 24-month study, no significant difference of bone contact ratio was obtained among three groups. These results suggest that one-stage zirconia implant connected with neighboring tooth could achieve higher bone contact ratio than single standing implants whichever they were connected by superstructure.