Correlation between skeletal and dental changes after mandibular setback surgery-first orthodontic treatment: Cone-beam computed tomography-generated half-cephalograms / 대한치과교정학회지

OBJECTIVE: To investigate skeletal and dental changes after application of a mandibular setback surgery-first orthodontic treatment approach in cases of skeletal Class III malocclusion. METHODS: A retrospective study of 34 patients (23 men, 11 women; mean age, 26.2 +/- 6.6 years) with skeletal Class III deformities, who underwent surgery-first orthodontic treatment, was conducted. Skeletal landmarks in the maxilla and mandible at three time points, pre-treatment (T0), immediate-postoperative (T1), and post-treatment (T2), were analyzed using cone-beam computed tomography (CBCT)-generated half-cephalograms. RESULTS: The significant T0 to T1 mandibular changes occurred -9.24 +/- 3.97 mm horizontally. From T1 to T2, the mandible tended to move forward 1.22 +/- 2.02 mm, while the condylar position (Cd to Po-perpendicular plane) shifted backward, and the coronoid process (Cp to FH plane) moved vertically. Between T1 and T2, the vertical dimension changed significantly (p < 0.05). Changes in the vertical dimension were significantly correlated to T1 to T2 changes in the Cd to Po-perpendicular plane (r = -0.671, p = 0.034), and in the Cp to FH plane (r = 0.733, p = 0.016), as well as to T0 to T1 changes in the Cp to Po-perpendicular plane (r = 0.758, p = 0.011). CONCLUSIONS: Greater alterations in the vertical dimension caused larger post-treatment (T2) stage skeletal changes. Studying the mandibular position in relation to the post-surgical vertical dimension emphasized the integral importance of vertical dimension control and proximal segment management to the success of surgery-first orthodontic treatment.

Correlation between skeletal and dental changes after mandibular setback surgery-first orthodontic treatment: Cone-beam computed tomography-generated half-cephalograms / 대한치과교정학회지

OBJECTIVE: To investigate skeletal and dental changes after application of a mandibular setback surgery-first orthodontic treatment approach in cases of skeletal Class III malocclusion. METHODS: A retrospective study of 34 patients (23 men, 11 women; mean age, 26.2 +/- 6.6 years) with skeletal Class III deformities, who underwent surgery-first orthodontic treatment, was conducted. Skeletal landmarks in the maxilla and mandible at three time points, pre-treatment (T0), immediate-postoperative (T1), and post-treatment (T2), were analyzed using cone-beam computed tomography (CBCT)-generated half-cephalograms. RESULTS: The significant T0 to T1 mandibular changes occurred -9.24 +/- 3.97 mm horizontally. From T1 to T2, the mandible tended to move forward 1.22 +/- 2.02 mm, while the condylar position (Cd to Po-perpendicular plane) shifted backward, and the coronoid process (Cp to FH plane) moved vertically. Between T1 and T2, the vertical dimension changed significantly (p < 0.05). Changes in the vertical dimension were significantly correlated to T1 to T2 changes in the Cd to Po-perpendicular plane (r = -0.671, p = 0.034), and in the Cp to FH plane (r = 0.733, p = 0.016), as well as to T0 to T1 changes in the Cp to Po-perpendicular plane (r = 0.758, p = 0.011). CONCLUSIONS: Greater alterations in the vertical dimension caused larger post-treatment (T2) stage skeletal changes. Studying the mandibular position in relation to the post-surgical vertical dimension emphasized the integral importance of vertical dimension control and proximal segment management to the success of surgery-first orthodontic treatment.

In vitro cytotoxicity of self-etching primers / 대한치과교정학회지

OBJECTIVE: Several ions and components are released from self-etching primers in the oral cavity. This may cause injury to the periodontal tissues throughout orthodontic treatment. The purpose of this study was to assess the cytotoxicity of self-etching primers to HGF-1, HaCaT, and RHEK cells. METHOD: Transbond XT Primer (3M Unitek, Monrovia, CA, USA), and self-etching primers, Clearfil SE Bond (Kuraray, Osaka, Japan), Transbond Plus SEP (3M Unitek, Monrovia, CA, USA), and Adper Prompt L-Pop (3M Unitek, Monrovia, CA, USA), were evaluated by MTT assay, and cellular changes were also observed. RESULTS: In all cells after 72 hours with all primers, severe morphological changes such as atrophy and necrosis were observed. In the MTT assay using HGF-1, Clearfil SE Bond, Transbond XT Primer, Transbond Plus SEP, and Adper Prompt L-Pop were lined up in order of ascending cytotoxicity.When using HaCaT, Clearfil SE Bond, Adper Prompt L-Pop, Transbond Plus SEP, and Transbond XT Primer were lined up in order of ascending cytotoxicity. When using RHEK, Clearfil SE Bond, Transbond XT Primer, Adper Prompt L-Pop, and Transbond Plus SEP were lined up in order of ascending cytotoxicity. CONCLUSION: The result of this study shows that care is needed because self-etching primers show cytotoxic properties similar to conventional primers.

One-Stage Vertebral Reconstruction Combined with Posterior Instrumentation by Posterolateral Approach for Spinal Metastasis

The authors present a series of 12 patients who underwent one-stage spondylectomy, vertebral reconstruction, posterior segmental stabilization for malignant metastatic disease. Major indication for this approach includes three column involvement or untolerable thoracotomy. This operative method involved the spondylectomy via a bilateral transpedicular or unilateral extracavitary approach, vertebral body reconstruction with methlymethacrylate (MMA), and posterior stabilization with sublaminar wiring in one stage. Postoperatively, all patients improved neurologically. Average neurologic improvement was 1.5 Frankel grade. Pain relief was obtained in all patients. Recovery of sphincter change was obtained 7(88%) of the 8 patients. One patient died postoperatively due to pneumonia. Spinal alignment was maintained in all. The major advantage of this approach is that circumferential decompression of the spine and stabilization can be obtained safely by one stage.

Surgical Treatment of Metastatic Spinal Tumor

The authors present a series of 35 patients who underwent operation for metastatic spinal tumor. Patients were operated via anterior, posterior or posterolateral and combined anterior-posterior approach. The anterior approach was used in cases where there was no involvement of the posterior column, tolerable of a thoracotomy and involvement of three or less adjacent vertebral bodies. The posterior or posterolateral approach was used in cases with involvement of the posterior column, disease at two seperated locations, intolerable of a thoracotomy and involvement of three columns. The combined anterior-posterior approach was used when it was not enough to obtain stabilization with anterior or posterior approach alone and expected greater than 1 year life expectancy. Twenty-five(89%) of the 28 patients improved neurologically following surgery. Average neurologic improvement was 1.3 Frankel grade. Pain relief was obtained in twenty-six(93%) of the 28 patients. Recovery of spincter change was obtained twelve(80%) of the 15 patients. Two patients died postoperatively due to DIC and pneumonia. Prior to operation, selective spinal angiography and embolization were performed in nine patients with metastases from renal carcinoma, thyroid cancer and hepatoma to reduce intraoperative bleeding. The authors believe that the choice of surgical approach has to be individualized for each patient depending on extent and location of the tumor, general condition of patient, goal of therapy and life expectancy.

A Clinical Analysis of Metastatic Spine Tumors: Analysis of Prognostic Factors and Scoring System for Prognostic Evaluation

The purpose of treatment for metastatic spine tumor is to improve the quality of life. So, it is very important to carefully select the surgical candidates to prevent unnecessary surgery-related morbidity and mortality. For this purpose, the authors have surveyed 200 cases of spinal metastasis treated by radiotherapy alone or radiotherapy plus surgery to determine prognostic factors. In this study, we attempted to examine retrospectively the four factors, e.g.,primary tumor, pretreatment neurologic status, general condition and degree of cancer extension, affecting the prognosis of metastatic spine tumors. Each factor was ranked from 1 to 3 points according to the severity and the total score for each patient was obtained by adding the these points. As a result, it was found that the total score was highly correlated to the survival period. While the patients with a total score of 6 or lower survived 100 days or less, those of 10 or higher survived 300 days or more on average. Therefore, authors believe this scoring system would be helpful to the determine treatment modalities and the selection of the most suitable operative procedures.

Vertebral Hemangioma Causing Cord Compression: A Case Report

We present a case of thoracic vertebral hemangioma causing spinal cord compression in a 57-year-old man. It is not common for vertebral hemangioma to cause neurologic deficits. The chief complaint of the patient was progressive paraparesis. Plain T-spine x-rays appeared normal. Axial and sagittal T1-weighted magnetic resonance(MR) imagings of T-spine showed multiple ring-like high signal lesion in vertebral body and decreased signal intensity at T7 with epidural mass causing spinal cord compression. Decompressive laminectomy and subtotal removal of the epidural mass were performed. The mass was reddish, friable and easily-coagulated. The postoperative computerized tomography(CT) scan of T-spine demonstrates characteristic thick vertical trabeculae and honeycomb pattern involving body and pedicles of T7 vertebrae. Bowel and urinary incontinence returned to normal two weeks following operation, and the patient was discharged with walking by sue of crutch three weeks later. Based on clinical features with this patient review of the literature, the authors recommend annual neurological and radiological examinations for patients harbouring hemangiomas with associated pain. Radiation therapy or embolization is an effective therapeutic alternative for patients with severe medically refractory pain. It is concluded that management of patients with a progressive neurological deficit should include prompt preoperative angiography and embolization, decompressive surgery with the approach determined by the degree of vertebral involvement and site of spinal cord compression, and postoperative radiation therapy in patients following subtotal tumor removal.