Abstract: A shell-like orthodontic appliance includes a shell-like body provided with a cavity accommodating a plurality of maxillary teeth. A sagittal adjustment portion is provided at a lingual side in an anterior region of the shell-like body. The sagittal adjustment portion is configured to adjust a maxillomandibular position relationship while at least to partially offset deformation of the shell-like body caused by occlusion, and the sagittal adjustment portion is at least partially connected to the lingual side in the anterior region of the shell-like body. The sagittal adjustment portion has a geometric structure configured to stabilize a maxillomandibular occlusion relationship and reduce a deformation of the shell-like body caused by occlusion while to adjust positions of teeth in a mandibular anterior region relative to a maxilla upward to target occlusion positions in a sagittal direction.