The present invention discloses a depth sleeve for a dental hand drill, which comprises a drill body and a depth sleeve. The front end of the dental handpiece incorporates a drill bit, and the depth sleeve fits over the drill bit. The depth sleeve can be cut with a knife or a scissors to cut the desired height position according to the drill bit of the dental handpiece, so that the end of the depth sleeve forms a depth basis for the drill bit to drill into the alveolar bone.本創作揭露一種牙科手機鑽頭的定深套筒，其包含由鑽頭本體及定深套筒所構成。該牙科手機前端係結合一鑽頭，而定深套筒恰可套置於鑽頭上。該定深套筒可用刀或剪進行切割，使其根據牙科手機之鑽頭對所需的高度位置進行切割，使定深套筒的末端形成鑽頭鑽入齒槽骨的深度依據。
