title: Evaluation of mechanical strengths of three types of mini-implants in artificial bones.
abstract: We investigates the effect of the anchor area on the mechanical strengths of infrazygomatic mini-implants. Thirty mini-implants were divided into three types based on the material and shape: Type A (titanium alloy, 2.0×12 mm), Type B (stainless steel, 2.0×12 mm), and Type C (titanium alloy, 2.0×11 mm).The mini-implants were inserted at 90° and 45° into the artificial bone to a depth of 7 mm, without predrilling. The mechanical strengths [insertion torque (IT), resonance frequency (RF), and removal torque (RT)] and the anchor area were measured. We hypothesized that no correlation exists among the mechanical forces of each brand. In the 90° tests, the IT, RF, and RT of Type C (8.5 N cm, 10.2 kHz, and 6.1 N cm, respectively) were significantly higher than those of Type A (5.0 N cm, 7.7 kHz, and 4.7 N cm, respectively). In the 45° test, the RFs of Type C (9.2 kHz) was significantly higher than those of Type A (7.0 kHz) and Type B (6.7 kHz). The anchor area of the mini-implants was in the order of Type C (706 mm2)>Type B (648 mm2)>Type A (621 mm2). Type C exhibited no significant correlation in intragroup comparisons, and the hypothesis was accepted. In the 90° and 45° tests, Type C exhibited the largest anchor area and the highest mechanical strengths (IT, RF, and RT) among the three types of mini-implants. The anchor area plays a crucial role in the mechanical strength of mini-implants.
authors.affiliation: School of Dentistry, College of Dental Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan; Department of Orthodontics, Dental Clinics, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan.
authors.forename: Yu-Chuan
authors.initials: YC
authors.lastname: Tseng
authors.affiliation: Faculty of Oral Hygiene, College of Dental Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan.
authors.forename: Ju-Hui
authors.initials: JH
authors.lastname: Wu
authors.affiliation: School of Dentistry, College of Dental Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan.
authors.forename: Chun-Chan
authors.initials: CC
authors.lastname: Ting
authors.affiliation: Faculty of Oral Hygiene, College of Dental Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan.
authors.forename: Hong-Sen
authors.initials: HS
authors.lastname: Chen
authors.affiliation: School of Dentistry, College of Dental Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan; Department of Oral and Maxillofacial Surgery, Dental Clinics, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan. Electronic address: komschen@gmail.com.
authors.forename: Chun-Ming
authors.initials: CM
authors.lastname: Chen
mesh_terms: D000497:Alloys / Q000737:chemistry*; D001696:Biomechanical Phenomena; D040761:Biomimetic Materials / Q000737:chemistry*; D001842:Bone and Bones / Q000737:chemistry / Q000502:physiology; D015921:Dental Implants; D003799:Dental Stress Analysis; D006801:Humans; D008422:Materials Testing; D052280:Orthodontic Anchorage Procedures / Q000295:instrumentation; D016382:Orthodontic Appliance Design; D013193:Stainless Steel / Q000737:chemistry*; D013314:Stress, Mechanical; D014025:Titanium / Q000737:chemistry*; D019415:Torque; D014732:Vibration
chemical_list: D000497:Alloys; D015921:Dental Implants; D013193:Stainless Steel; D014025:Titanium
keywords: Anchor area; Infrazygomatic mini-implant; Insertion torque; Removal torque; Resonance frequency