アブストラクト（19巻4号：神奈川歯学）

神奈川歯学

Japanese

Title　： IV級コンポジットレジン修復窩洞の窩縁形態について
Subtitle　： 原著
Authors　： 西村光太郎, 野村健一郎, 前川彰男, 山崎恭敬, 篠塚嘉昭, 岩本次男
Authors（kana）　：
Organization　： 神奈川歯科大学保存学教室第一講座
Journal　： 神奈川歯学
Volume　： 19
Number　： 4
Page　： 447-458
Year/Month　： 1985 / 3
Article　： 原著
Publisher　： 神奈川歯科大学学会
Abstract　： 「はじめに」 IV級窩洞の修復においては, 外力が常に舌側に加わるにもかかわらず, 修復物の保持を図るための形態を, 唇舌径のひ薄な前歯部歯質中に設定しなければならないため, ややもすると保持力が不足して修復物の脱落を招く結果となり, また, 有髄歯の場合には不用意な保持形態の付与により歯髄傷害の危険性が増大するなど, 窩洞形成に際しては種々の問題点が伴っていた. しかしながら, 今日では接着性コンポジットレジン修復材の進歩, 発展によりそれらもほぼ解決されて修復物の保持も比較的容易に図られ, また, その効果もかなり期待されるようになってきた. 本修復法の保持力の主体となる接着性の発現は, 酸処理により作られたエナメル質表面の微細な凹凸とレジンタッグとの機械的嵌合によるため, 修復物の保持にはエナメル質窩縁部の形態がとくに関与すると考えられ, このことからIV級あるいはVI級窩洞の窩縁形態については過去に多くの報告がなされている.
Practice　： 歯科学
Keywords　：

English

Title　： Study on the Marginal Form of Class IV Preparation for Composite Resin Restoration
Subtitle　：
Authors　： Kotaro NISHIMURA, Kenichiro NOMURA, Akio MAEKAWA, Yukinori YAMAZAKI, Yoshiaki SHINOZUKA, Tsugio IWAMOTO
Authors（kana）　：
Organization　： Department of Restorative Dentistry, Kanagawa Dental College
Journal　： Kanagawa Shigaku
Volume　： 19
Number　： 4
Page　： 447-458
Year/Month　： 1985 / 3
Article　： Original article
Publisher　： Kanagawa Odontological Society
Abstract　： Though it is considered that the retention and marginal closure of Class IV composite resin restoration are significantly affected by the marginal form of preparation, much have not been systematically studied in regard to this subject. In the present study, therefore, the marginal forms of Class IV preparations were varied in type and dimension and their effects on the retentive and sealing properties in both cases with and without the thermal stress were examined. 180 extracted human maxillary central incisors were prepared for Class IV composite resin restorations either chamfered or shouldered type of marginal form with various dimensions were given to the preparations. In addition, butt-joint type preparation was also applied as a control・ After insertion of restorative materials (Clearfil Bond System), 80 out of 180 specimens were subjected to 100 temperature cycles between two baths at 4℃ and 60℃ respectively, for 30 seconds. Then, all specimens were loaded in order to determine the retentive strength and then the fractured surfaces were observed with naked eye and also by SEM. As to the other exrerimental group, additional 60 specimens prepared by the same manner described above were provided to the micro-lcakage test for evaluating the marginal integrity and adaptability to the prepared walls. For this test, 0.2% basic fuchsin solution was used as a tracer. From the results obtained, marginal forms could be classified into three groups according to their retentive strengths, decreasing tendencies by the thermal stress and fracture modes at the interface. In the first group, in which the marginal preparations were limited within marginal enamel regardless of the types of preparation applied, retentive strength was not so high but insignificant reduction was seen by thermal stress, and the majority of specimens demonstrated the cohesive fracture. On the contrary, the case of marginal preparation located not only on enamel surface but also extended to dentin exhibited the higher retentive strength compared with that of the first group, but they considerably decreased by thermal stress and the partial adhesive fracture was observed in some cases. However, in this group, shouldered type preparation showed the highest strength because of its angled shape which played a supporting effect to the restoration. Butt-joint type and deeper chamfered preparations were classified in the third group and the lowest strength were shown irrespective of thermal stress. In conclusion, it could be suggested that the marginal form should possess the proper extent and texture of prepared enamel surface which make it possible the suitable tag formation of restorative material.
Practice　： Dentistry
Keywords　：