The present disclosure provides for a micro-needle device (100, 200, 300, 400) that includes a micro-needle array (102, 202, 302, 402) and a liquid connection port (104, 204, 304, 404). The micro-needle array includes a base (106, 206, 306, 406), a sidewall (108, 208, 308, 408) and a top (110, 210, 310, 410), where the base includes two or more of an elongate micro-needle (112, 212, 312, 412) having an interior surface (114, 214, 314, 414) defining an opening 8116, 216, 316, 416) through the elongate micro-needle. The base has a first major surface (118, 218, 318, 418) and a second major surface (120, 220, 320, 420) through which the opening of the elongate micro-needle passes to provide a passage across the base. The top has an interior surface (122, 222, 322, 422) and the sidewall has an interior surface (126, 226, 326, 426), where the interior surface of the side wall, the interior surface of the top and the first major surface of the base define a volume (130, 230, 330, 430). The liquid connection port has a fluid connection with the volume of the micro-needle array such that dental local anesthetic fed through the connection port can exit through the opening of the elongate micro-needle.
