PROBLEM TO BE SOLVED: To provide a lower jaw impression tray, a lower jaw impression tray, and an impression tray set capable of accurately obtaining an impression of the jaw ridge even in the case of a relatively low and wide ridge. A tray 10C for impression of an upper jaw includes a base portion 14 having a convexly curved side facing a palate and a curved recessed portion 16 provided along an outer edge of the base portion 14 and covering the upper ridge. And the base portion 14 is placed on a horizontal plane, the lowest bottom surface portion of the recessed portions 16 of the left and right maxillary ridge wall portions 12 in the vertical plane orthogonal to the central axis of the base portion 14 in the longitudinal direction. The line connecting M is defined as a lower width imaginary line L1, and the angle θ on the obtuse side between the lower width imaginary line L1 of the straight lines passing through the bottom surface portion M and the inner surface of the outer wall top of the maxillary ridge wall portion 12 is the smallest. When the straight line is the inclined line K, the angle θ formed by the inclined line K and the lower width virtual line L1 is 139° or more and 150° or less in at least a part of the region corresponding to the molar teeth of the recess 16. [Selection diagram] Fig. 9【課題】比較的低くかつ幅広な顎堤の場合であっても顎堤の印象を正確に採得できる下顎印象用トレー、下顎印象用トレー及び印象用トレーセットを提供する。【解決手段】上顎印象用トレー１０Ｃは、口蓋と対面する側が凸状に湾曲したベース部１４と、ベース部１４の外縁に沿って設けられ上顎堤を覆う湾曲した凹部１６を備えた上顎堤壁部１２と、を備え、ベース部１４を水平面に載置した状態で、ベース部１４の長手方向の中心軸と直交する鉛直面において、左右の上顎堤壁部１２の凹部１６の最も低い底面部Ｍを結ぶ線を下幅仮想線Ｌ１とし、底面部Ｍと上顎堤壁部１２の外壁頂部の内面とを通る直線のうち下幅仮想線Ｌ１との間の鈍角側の角度θが最も小さくなる直線を傾斜線Ｋとしたとき、凹部１６の臼歯に対応する領域の少なくとも一部において、傾斜線Ｋと下幅仮想線Ｌ１とがなす角度θが、１３９°以上、１５０°以下である。【選択図】図９
