A Case of Orthognathic Surgery using a Custom-made Bender and Tap Screws for Tentative Fixation of Absorbable Plates

Abstract

Introduction: An absorbable plate with good tissue affinity and without necessity of removal is a reliable osteosynthetic material used to treat jaw deformity. However, bending the plate with two kinds of conventional benders is operationally complicated, particularly when forming appropriate steps. This paper reports a case of jaw deformity treatment in which a new custom-made bender (Step Bender^TM) and tap screws for tentative fixation were used to adjust and fix the absorbable plate.
Case report: An 18-year-old male patient with a clinical history of untreated occlusal dysfunction noticed at approximately 13 years old. Following a visit to an orthodontist, the patient was referred to our hospital in November 2007 with the chief complaint of occlusion deficiency. Mandibular prognathism was diagnosed by cephalometric analysis. In accordance with the patient's wishes and judging from the displacement distances, the treatment procedures were decided to be: anterior displacement of the maxilla; posterior displacement followed by counterclockwise rotation of the mandible; and anterosuperior displacement of the mentum. An absorbable plate was used in view of the patient's condition.
Under general anesthesia, conventional two-jaw osteotomy was performed in August 2009. Osteosynthesis was applied after maxillary osteotomy in Le Fort I. The plate bender “Step-Bender^TM” developed by Takiron Company for maxillary osteotomy was used for plate bending. The plate was held in an appropriate position with the Step-Bender^TM and heated once. Then, the plain plate could be bent manually in both upward and downward directions simultaneously to simplify the configuration and shorten the operation time. Newly developed “tap screws for tentative fixation” were also used in the procedure. The “tap screws for tentative fixation” were used for cutting the tap, and then for fixing the plate temporally, thus improving the efficiency of the screw fixing procedure. The postoperative position of the absorbable plate was confirmed in 3DCT images and smooth osteosynthesis was confirmed with occlusion control.
The patient remained under postoperative observation for two years with no problem.Conclusion: The case in this report demonstrated the successful clinical application of an absorbable plate with a new tool, Step-Bender^TM, and temporary fixing tap screws for tentative fixation. Both apparatuses were considered to be suitable for this case.