This research develops an innovative free-form surface scanning system using laser triangulation for 3D dental data required for crown reconstruction. This novel design employs double laser diodes to produce two 45° structured-light lines projecting onto the plaster tooth models and three CCD cameras to capture deformed fringes to achieve fast and accurate 3D surface measurement of plaster tooth models. Effective strategies were implemented to overcome problems such as potential measurement occlusion and data registration inaccuracy, commonly encountered by other data scanning methods. The developed system has distinctive features such as laser projecting angles for complete surface measurement coverage, digitizing accuracy, and compact scanner volume for potential applications on 3D surface digitization of tiny industrial components. Experimental results verified that the proposed system achieves a 20µm digitizing accuracy and possesses fast scanning capability. Maximum one minute is used for a single-tooth model and 30 minutes are used for scanning the whole jaw.