Electronic Thesis and Dissertation Repository

Thesis Format



Master of Clinical Dentistry




Purpose: To obtain information on the clinical utilization of orthodontic miniscrews (OMSs) among orthodontists in Canada

Methods: Web-based software was used to fabricate a questionnaire in which respondents were asked questions regarding their usage of OMSs in their clinical practice. The survey consisted of between 11 and 39 questions, depending on the respondents’ answers. The survey was distributed via email to the 353 active Canadian members of the American Association of Orthodontists (AAO).

Results: A total of 82 Canadian orthodontists responded to the survey, for a response rate of 23.2%. Among them, 65.8% currently used miniscrews in their clinical practice. The most common reason given for not using OMSs was a doctor preference for conventional less invasive mechanics. At the time of the survey, most Canadian orthodontists who were currently using OMSs had been doing so for 6-10 years. Most respondents were placing OMSs personally with the primary reason for referral being the longer chair time required for placement. The most commonly used placement locations were the maxillary and mandibular alveolar buccal areas. The most common applications were posterior intrusion and molar protraction. Most respondents used a panoramic radiograph to plan OMS placement and used local infiltration for anesthesia. The majority of orthodontists never used a surgical guide, drilled a pilot hole, or measured insertion torque during OMS placement. Both direct and indirect forces were frequently applied to OMSs, and the load was usually applied immediately. The most frequently observed complications were screw loosening and soft tissue overgrowth or irritation. The mean self-reported OMS failure rate was 19.6% ± 15.7%, with failures most frequently reported in the maxillary alveolar buccal areas. Most respondents felt that OMSs have increased treatment options, reduced patient compliance required, and decreased the number of cases requiring prosthodontic treatment. A majority of Canadian orthodontists are satisfied with their OMS treatment outcomes with most agreeing that OMSs have made treatment more predictable and better overall.

Conclusions: This survey illustrates that while Canadian orthodontists in 2020 have similar opinions in regard to OMS usage with orthodontists surveyed in the past and in other countries, a few differences do exist.

Summary for Lay Audience

Orthodontists are dentists who go through additional training to specialize in the diagnosis, prevention and correction of malpositioned teeth and jaws, using removable or fixed appliances like braces and clear aligners. When an orthodontist comes up with a treatment plan for a patient, he or she must take into account the forces that will be applied to the teeth, because forces have equal and opposite reactions that are not always helpful. A recent advance in the field of orthodontics has been the development of a miniature implant, resembling a small screw, that is temporarily placed into bone. These are called “orthodontic miniscrews”, or OMSs. An orthodontist may place one or more OMS into a patient’s jaws, usually between the roots of teeth or on the roof of the mouth. These devices allow the orthodontist to accomplish difficult movements of teeth that would other have undesirable side effects. Surveys have been published that investigate how orthodontists from other countries are using OMSs, and the purpose of this study was to determine how many Canadian orthodontists are using OMSs, what problems OMSs are being used to treat, complications the orthodontists may have noticed, and overall success rates.