Stephan Christian Möhlhenrich1, Maximilian Brandt2, Kristian Kniha3, Andreas Prescher4, Frank Hölzle3, Ali Modabber3, Michael Wolf2, Florian Peters3. 1. Department of Orthodontics, University Hospital of RWTH Aachen, Pauwelsstraße 30, 52074, Aachen, Germany. smoehlhenrich@ukaachen.de. 2. Department of Orthodontics, University Hospital of RWTH Aachen, Pauwelsstraße 30, 52074, Aachen, Germany. 3. Department of Oral and Maxillofacial Surgery, University Hospital of RWTH Aachen, Pauwelsstraße 30, 52074, Aachen, Germany. 4. Medical Faculty of RWTH Aachen, Institute of Molecular and Cellular Anatomy, Pauwelsstraße 30, 52074, Aachen, Germany.
Abstract
OBJECTIVE: The aim of this cadaveric study was to measure the transfer accuracy of orthodontic mini-implant placement at the anterior palate depending on tooth-borne or gingiva-borne guide support. MATERIALS AND METHODS: Forty orthodontic mini-implants were placed paramedian in the anterior palate of 20 cadaver heads using tooth-borne (TBG) or gingiva-borne guides (GBG). Placement was planned after superimposition of lateral cephalograms and corresponding plaster models. After mini-implant placement, digital impressions were taken with scanbodies. For the measurement of both linear and angle deviations, virtual planning models and postoperative oral scans were compared using automatic surface registration based on an iterative closest point algorithm. RESULTS: Statistical differences between TBG and GBG were detected for lateral deviations 0.88 mm (SD 0.46) versus 1.65 mm (SD 1.03) (p = .004) and sagittal angular deviations 3.67° (SD 2.25) versus 6.46° (SD 5.5) (p = .043). No differences were found for vertical deviations 2.34 mm (SD 0.74) versus 2.14 mm (SD 0.73) (p = .40) and transverse angular deviations 3.60° (SD 2.89) versus 4.06° (SD 3.04) (p = .62). CONCLUSIONS: The use of surgical guides based on silicone provides sufficient control of orthodontic mini-implant placement and is comparable to CAD/CAM templates. However, when compared with guided dental implantology, the planned mini-implant position is more inaccurate. However, accuracy can be significantly increased by guide extension involving the teeth. Clinical investigations have to prove if the accuracy is sufficient for receiving an orthodontic appliance. CLINICAL RELEVANCE: The use of lateral cephalograms and plaster models for silicone guide construction leads to lower radiation exposure and provides sufficient accuracy for palatal orthodontic mini-implant placement.
OBJECTIVE: The aim of this cadaveric study was to measure the transfer accuracy of orthodontic mini-implant placement at the anterior palate depending on tooth-borne or gingiva-borne guide support. MATERIALS AND METHODS: Forty orthodontic mini-implants were placed paramedian in the anterior palate of 20 cadaver heads using tooth-borne (TBG) or gingiva-borne guides (GBG). Placement was planned after superimposition of lateral cephalograms and corresponding plaster models. After mini-implant placement, digital impressions were taken with scanbodies. For the measurement of both linear and angle deviations, virtual planning models and postoperative oral scans were compared using automatic surface registration based on an iterative closest point algorithm. RESULTS: Statistical differences between TBG and GBG were detected for lateral deviations 0.88 mm (SD 0.46) versus 1.65 mm (SD 1.03) (p = .004) and sagittal angular deviations 3.67° (SD 2.25) versus 6.46° (SD 5.5) (p = .043). No differences were found for vertical deviations 2.34 mm (SD 0.74) versus 2.14 mm (SD 0.73) (p = .40) and transverse angular deviations 3.60° (SD 2.89) versus 4.06° (SD 3.04) (p = .62). CONCLUSIONS: The use of surgical guides based on silicone provides sufficient control of orthodontic mini-implant placement and is comparable to CAD/CAM templates. However, when compared with guided dental implantology, the planned mini-implant position is more inaccurate. However, accuracy can be significantly increased by guide extension involving the teeth. Clinical investigations have to prove if the accuracy is sufficient for receiving an orthodontic appliance. CLINICAL RELEVANCE: The use of lateral cephalograms and plaster models for silicone guide construction leads to lower radiation exposure and provides sufficient accuracy for palatal orthodontic mini-implant placement.
Authors: Stephan Christian Möhlhenrich; Maximilian Brandt; Kristian Kniha; Anna Bock; Andreas Prescher; Frank Hölzle; Ali Modabber; Golamreza Danesh Journal: J Orofac Orthop Date: 2020-07-06 Impact factor: 1.938