PROBLEM TO BE SOLVED: To provide a dowel pin for use in a working model for dental technique in which gypsum is prevented from entering insertion holes of a support base and the wobble in the work when processing a tooth model can be prevented, and provide the support base and a plug capable of preventing entry of the gypsum to the insertion holes.SOLUTION: A metallic dowel pin is implanted in a fixing plate 106 where a tooth model is fixed and is formed of gypsum. A support base 102 is provided with insertion holes 18 and is formed of synthetic resin. The dowel pin is configured such that an upper body part 1 has a pillar shape or a truncated-cone-shape where an outer diameter is narrowed toward the tip direction, and a lower body part 2 has an outer diameter gradually decreasing toward the distal end, the lower body part that has an irregular substantially truncated cone shape where the some side surface is a flat surface extending in the longitudinal direction to a dowel pin distal end and has one or two side surfaces being the flat surface. The support base has insertion holes with the shape where the shape of the dowel pin insertion holes can be fitted to the upper body part and the lower body part of the dowel pin.SELECTED DRAWING: Figure 11COPYRIGHT: (C)2018,JPO&INPIT【課題】 支持基台の挿入孔に石膏が侵入せず、歯形模型を加工する際の作業でのぐらつきを防止できる歯科技工用作業模型に使用されるダウエルピン、支持基台及び挿入孔への石膏の侵入を防止し得る栓を提供する。【解決手段】 歯形模型が固定される石膏で形成されている固定用プレート106に植設される金属製のダウエルピンと、その挿入孔18が設けられた合成樹脂から形成されている支持基台102であって、ダウエルピンは上部本体部1は円柱状又は先端方向に向かって外径が狭められた円錐台状であり、下部本体部2は、先端部に向けて外径が漸減しており、その一部の側面がダウエルピン先端部まで長手方向に伸びる平坦面である変則的な略円錐台形状であり、且つ前記平坦面である側面を1つ又は2つ有しており、 支持基台はダウエルピン挿入孔の形状がダウエルピンの上部本体部と下部本体部が嵌合し得る形状の挿入孔を有する。【選択図】 図11
