The present disclosure supplies molar appliances having a tooth bonding base that includes compound curvature in the mesial-distal direction, providing for a closer fit relative to the buccal surface contour. The appliances can also feature a funneled entry to an archwire passage that includes a plurality of surfaces with a convex curvature, providing a curved taper to a distal section of the passage. The continuously curved surfaces guide the end of an archwire into the passage, while minimizes or avoiding abrupt transition areas that can impede insertion. The appliances of the present disclosure can include a buccal surface on the appliance body that is substantially parallel to the torque plane of the appliance.
