Comparison of the postoperative stability after repositioning of the maxilla with Le Fort I osteotomy using four- versus two-plate fixation.

INTRODUCTION: Le Fort I osteotomy procedures requires miniplates fixation in both the aperture piriformis and zygomaticomaxillary buttress. PURPOSE: The purpose of this study was to compare the postoperative stability of the Le Fort I osteotomy using four-plate versus two-plate fixation. MATERIAL AND METHODS: This study involved 39 Class III patients who underwent one-piece Le Fort I osteotomy with bilateral sagittal split ramus osteotomy. In group I, four miniplates were placed at the apertura piriformis and the zygomaticomaxillary buttress, whereas, in group II, fixation was achieved with two miniplates bilaterally placed at the piriform apertura with no posterior fixation. Linear and angular measurements included maxillary sagittal and vertical positions. The primary outcome of this study was stability, as recorded by lateral cephalometric measurements of the preoperative, immediately postoperative and late postoperative periods. RESULTS: Significant immediate postsurgical changes were found in both groups. In the late postoperative cephalometric measurements, all skeletal parameters showed significant stability in groups I and II. In terms of vertical and sagittal relapse, there was no significant difference between the four-plate and two-plate groups (p1=0.686 and p2=0.513, respectively). CONCLUSION: A good postoperative stability can be obtained with a two-plate fixation after one-piece Le Fort I osteotomy.

The effects of ozone application on genotoxic damage and wound healing in bisphosphonate-applied human gingival fibroblast cells.

OBJECTIVES: Medication-related osteonecrosis of the jaws (MRONJ) is an extremely therapy-resistant disease involving the jaws especially following bisphosphonate treatment. Bisphosphonates accumulate in bone in concentrations sufficient to be directly toxic to the oral epithelium. Current therapeutic options are inadequate for the prevention and treatment of MRONJ. The aim of this study was to investigate effects of ozone gas plasma therapy on wound healing in bisphosphonate-applied human fibroblasts. MATERIAL AND METHODS: Human primary gingival fibroblasts were cultured. Cytotoxic concentrations (IC50) of bisphosphonates (pamidronate (PAM), alendronate (ALN), and zoledronate (ZOL)) were determined by MTT test. A 60 µg/µl for 30 s of ozone gas plasma application was performed to all experimental culture flasks after drug treatment at 24-h intervals as 3 s/cm2. Genotoxic damages were evaluated by comet assay and wound healing was determined by in vitro scratch assay. RESULTS: PAM, ALN, and ZOL applications caused genotoxic damage on primary human gingival fibroblast DNA. Ozone gas plasma therapy significantly decreased the genotoxic damage (p < 0.05), and this application provided 25, 29, and 27% less genotoxic damage in order of ALN, PAM, and ZOL groups. Ozone gas plasma therapy significantly increased wound healing rates both in postsurgical 24th and 48th hours for all doses of experimental drug groups (p < 0.05). CONCLUSION: The ozone gas plasma application decreased genotoxic damage effect of bisphosphonate usage while improved the wound closure rate on human gingival fibroblasts. CLINICAL RELEVANCE: Ozone gas plasma therapy may be helpful in prevention of gingival healing delay in MRONJ pathogenesis especially when applied simultaneously with surgical intervention.