Guided Osteotomy and Guided Autotransplantation for Treatment of Severely Impacted Teeth: A Proof-of-Concept Report.

INTRODUCTION: The aim was to present a novel surgical technique using virtually preplanned 3-dimensional (3D)-printed templates for guided osteotomies. These were to ensure atraumatic uncovering of a severely impacted donor tooth including guided drilling of the recipient alveolus followed by a secure autotransplantation procedure. METHODS: This report presents an autotransplantation procedure of a 14-year-old patient with a severely impacted second premolar and extensive contact to the roots of the adjacent teeth and the inferior alveolar nerve. Autotransplantation of the impacted premolar was virtually performed using modified methods from guided implant surgery in order to prefabricate 3D-printed templates with the aid of a fully digital workflow. RESULTS: Satisfactory treatment could be achieved using surgical templates for guided osteotomies of the surgical access, guided drilling of the recipient site, and occlusal reference template ensuring autotransplantation in the appropriate 3D location of the graft. An atraumatic approach could be ensured with an extraoral time of 46 seconds by 1 fitting attempt; no injuries or altered sensation of the inferior alveolar nerve were present. A vital natural tooth could be observed. CONCLUSIONS: This innovative technique uses for the first time a fully implemented digital workflow for guided osteotomies, guided drilling, and guided autotransplantation of a severely impacted tooth. 3D-printed templates could ensure a guided atraumatic approach and facilitate highly complex treatments by virtually implementing recommended guidelines in future autotransplantations.

Guided Autotransplantation of Teeth: A Novel Method Using Virtually Planned 3-dimensional Templates.

INTRODUCTION: The aim of this study was to introduce an innovative method for autotransplantation of teeth using 3-dimensional (3D) surgical templates for guided osteotomy preparation and donor tooth placement. METHODS: This report describes autotransplantation of immature premolars as treatment of an 11-year-old boy having suffered severe trauma with avulsion of permanent maxillary incisors. This approach uses modified methods from guided implant surgery by superimposition of Digital Imaging and Communications in Medicine files and 3D data sets of the jaws in order to predesign 3D printed templates with the aid of a fully digital workflow. RESULTS: The intervention in this complex case could successfully be accomplished by performing preplanned virtual transplantations with guided osteotomies to prevent bone loss and ensure accurate donor teeth placement in new recipient sites. Functional and esthetic restoration could be achieved by modifying methods used in guided implant surgery and prosthodontic rehabilitation. The 1-year follow-up showed vital natural teeth with physiological clinical and radiologic parameters. CONCLUSIONS: This innovative approach uses the latest diagnostic methods and techniques of guided implant surgery, enabling the planning and production of 3D printed surgical templates. These accurate virtually predesigned surgical templates could facilitate autotransplantation in the future by full implementation of recommended guidelines, ensuring an atraumatic surgical protocol.

Influence of repeat surgery on treatment time in the interdisciplinary management of impacted maxillary canines: A retrospective cohort study.

PURPOSE: To evaluate the effect of repeat surgery on treatment time in the interdisciplinary management of impacted maxillary canines. MATERIAL AND METHODS: This retrospective cohort study enrolled patients referred for computed tomographic examination for impacted maxillary canines within a 5-year observational period. The occurrence of repeat surgery was analysed with regard to treatment time, canine location, and surgical exposure technique. RESULTS: A total of 55 patients with 79 impacted maxillary canines were analysed. Of those, 83.6% did not present with complications that would have prompted repeat surgery during their treatment. For patients requiring repeat surgery, time until clinically visible movement of the canine was significantly longer (p < 0.001), whereas time between initial movement and eruption into the oral cavity was significantly shorter (p < 0.001). Overall treatment time did not differ significantly (p = 0.13). An open surgical exposure technique was associated with a significantly lower occurrence of repeat surgeries (p = 0.03). Bilateral impaction of canines significantly prolonged overall treatment time (p = 0.01). CONCLUSIONS: In the event of initial treatment failure during the interdisciplinary management of impacted maxillary canines, repeat surgery should be considered, which has limited effect on overall treatment time. An open surgical exposure technique is preferable.

Miniscrews in orthodontic treatment: review and analysis of published clinical trials.

INTRODUCTION: A systematic review of effects related to patient, screw, surgery, and loading on the stability of miniscrews was conducted. METHODS: Reports of clinical trials published before September 2007 with at least 30 miniscrews were reviewed. Parameters examined were patient sex and age, location and method of screw placement, screw length and diameter, time, and amount of loading. RESULTS: Fourteen clinical trials included 452 patients and 1519 screws. The mean overall success rate was 83.8% + or - 7.4%. Patient sex showed no significant differences. In terms of age, 1 of 5 studies with patients over 30 years of age showed a significant difference (P <0.05). Screw diameters of 1 to 1.1 mm yielded significantly lower success rates than those of 1.5 to 2.3 mm. One study reported significantly lower success rates for 6-mm vs 8-mm long miniscrews (72% vs 90%). Screw placement with or without a surgical flap showed contradictory results between studies. Three studies showed significantly higher success rates for maxillary than for mandibular screws. Loading and healing period were not significant in the miniscrews' success rates. CONCLUSIONS: All 14 articles described success rates sufficient for orthodontic treatment. Placement protocols varied markedly. Screws under 8 mm in length and 1.2 mm in diameter should be avoided. Immediate or early loading up to 200 cN was adequate and showed no significant influence on screw stability.