保乳术后放疗中钛夹动度与乳腺大小及钛夹位置的相关性

【摘要】目的:分析保乳术后放疗患者钛夹动度，并探讨其与乳腺大小、钛夹位置的相关性。方法:随机选取保乳术后放疗患者15例，每周两次锥形束CT。测量乳腺基底面直径（D）和乳高轴（H），以瘤床质心为原点将临床靶区分4个象限。记录各象限内钛夹在左右、腹背、头脚方向动度（MLR、MAP、MSI）以及其与临床靶区最内、最前、最上的距离（DSLR、DSAP、DSSI）。结果:MLR、MAP、MSI分别为（2.2±3.0）、（-1.1±3.6）、（0.8±4.7） mm；系统误差Σ在左、右、腹、背、头、脚分别为1.7、2.2、2.0、2.4、2.9、3.0 mm，随机误差σ分别为2.4、4.0、3.2、4.0、4.7、4.7 mm；靶区对应外放5.9、8.3、7.2、8.8、10.5、10.9 mm。一象限内，当D×H<99.89 cm2，MAP和D×H强相关（r=0.805），MLR、MAP均和DSLR、DSAP、DSSI强正相关（r=0.94, 0.94, 0.91；0.87, 0.91, 0.92），MSI和DSLR、DSAP强正相关（r=0.91, 0.94）；四象限内，当D×H<90.71 cm2，MAP和DSLR，MSI和DSAP均强负相关（r=-0.96；-0.95），MLR和DSLR强正相关（r=0.91）。结论:钛夹动度有各向异性，以SI方向外扩最大，并易受乳腺大小、钛夹位置影响。     

Treatment of skeletal open bite using a navigation system: CAD/CAM osteotomy and drilling guides combined with pre-bent titanium plates

Severe skeletal open bite associated with posterior vertical maxillary excess and mandibular deformity is considered a difficult problem in orthodontic and surgical treatment. This study used a navigation system for the correction of severe skeletal open bite in order to accurately transfer the virtual plan to the actual operation and achieve precise rigid internal fixation in bimaxillary osteotomies of the jaws. Twelve patients with a severe skeletal open bite associated with vertical maxillary excess and mandibular deformity were recruited. All patients underwent Le Fort I osteotomy and bilateral sagittal split ramus osteotomy with the guidance of this navigation system. Computed tomography and cephalometric examinations were performed to evaluate the correction of the deformity. Deviations between the simulated plan and actual postoperative outcome were measured to determine the precision of the surgery. Satisfactory and stable results were achieved in all patients postoperatively, without complications or relapse during follow-up. Photographs and cephalometric evaluations showed that the facial profile and occlusion were improved. Assessment of the deviations between the simulated plan and actual postoperative outcome showed that the navigation system can precisely transfer the virtual plan to the actual operation. The results suggest that the navigation system can accurately transfer the virtual plan to the actual operation during bimaxillary jaw osteotomies, without relapse, in patients with a severe skeletal open bite.     

“One-piece” patient-specific reconstruction plate for double-barrel fibula-based mandibular reconstruction

Segmental mandibular defects require reconstruction. The fibula flap serves as a versatile flap in restoring mandibular contour and bony height. With the advances in computer-aided design and additive manufacturing technology, an innovative “one-piece” patient-specific reconstruction plate to facilitate double-barrel fibula flap shaping and bone securing was developed; the plate is described in this study. The “one-piece” plate is fabricated with individualized specifications and is mainly composed of three components: the long-bar reconstruction plate, a short-bar plate, and connecting bars. Our initial experiences showed that mandibular reconstructive surgery was greatly facilitated by the “one-piece” reconstruction plate for double-barrel fibula flap reconstruction and achieved satisfactory outcomes. A well-designed clinical trial is required to confirm the superiority of the “one-piece” reconstruction plate in the future. ClinicalTrials.gov registration: NCT03057223.     

Treatment of hemimandibular hyperplasia by computer-aided design and computer-aided manufacturing cutting and drilling guides accompanied with pre-bent titanium plates

PurposeThe treatment of hemimandibular hyperplasia (HH) is difficult by performing condylectomy and orthognathic surgery in one stage. This study investigated the clinical feasibility of treating HH with computer-aided design and computer-aided manufacturing (CAD/CAM) cutting and drilling guides and the pre-bent titanium plates to improve the accuracy of operation to avoid condyle reconstruction.Methods12 patients diagnosed with HH were included in this study from 2014 to 2018. Conservative condylectomy and bimaxillary orthognathic surgery were performed in all patients. The CAD/CAM cutting and drilling guides and the pre-bent titanium plates were used to guide surgeries. Follow-up and radiographic examinations were performed. The difference between virtually simulated and postoperative models was measured.ResultsAll patients got satisfactory and stable results, without complications or obvious relapse during follow-up. Occlusion relationship, temporomandibular joint function and facial symmetry were improved obviously after surgery. Comparison between simulated plans and actual postoperative outcomes showed that the surgical plans were transferred accurately.ConclusionsCAD/CAM cutting and drilling guides and the pre-bent titanium plates described in this paper can help transferring the results from computer simulation to the operating room accurately. Conservative condylectomy can be operated exactly matching bimaxillary orthognathic surgery for treating HH, avoiding condyle reconstruction.     

Experimental peri-implant mucositis around titanium and zirconia implants in comparison to a natural tooth: part 2—clinical and microbiological parameters

The aim of this study was to assess the clinical and microbiological parameters around dental zirconia and titanium implants compared with natural teeth during experimental plaque accumulation. Clinical parameters were evaluated (gingival index, plaque index, bleeding on probing, and probing pocket depth). Microbiological samples were analyzed for total bacterial cell counts, as well as Tannerella forsythia and Prevotella intermedia counts. A statistically significant difference over time was observed in the groups in terms of the gingival index (P < 0.001), plaque index (P < 0.001), and bleeding on probing (P = 0.039). The lowest mean total number of bacterial cells was measured around the teeth, followed by the zirconia implants; the highest values were found around the titanium implants. T. forsythia and P. intermedia values showed significant changes over time and sessions around the titanium implants. Compared to the soft tissues around zirconia implants and the teeth, those around titanium implants developed a stronger inflammatory response to experimental plaque accumulation in terms of the total number of bacterial cells and T. forsythia and P. intermedia values.