Arthroscopic Reduction and Internal Fixation in Patients with Acetabular Posterior Wall Fractures

Background@#This study aimed to access the radiologic and clinical outcomes after arthroscopic reduction and internal fixation with screws in patients with posterior wall fractures of the acetabulum. @*Methods@#From May 2013 to December 2019, 13 patients (11 men and 2 women) with posterior wall fractures of the acetabulum were treated with arthroscopic reduction and internal fixation with screws at two medical centers. The mean age at the index operation was 39 years (range, 22–58 years). The mean duration of follow-up was 23 months (range, 12–46 months). Clinical assessment was performed using the modified Merle d'Aubigné and Postel functional scoring system. The maximum displacement of acetabular or femoral head fragments detected on radiographs was used as radiographic results. Secondary osteoarthritis, osteonecrosis, or heterotrophic ossification was assessed at the latest follow-up. @*Results@#Bony union was shown at 12 weeks of follow-up in all patients. The radiologic outcomes showed an anatomical reduction in 11 patients and a satisfactory reduction in 2 patients. The modified Merle d'Aubigné and Postel functional score was excellent in 7 patients, good in 5 patients, and fair in 1 patient. Two patients had transient pudendal nerve palsy after hip arthroscopy. However, no sciatic nerve palsy occurred. At the latest follow-up, there was no heterotopic ossification, osteonecrosis of the femoral head, or posttraumatic osteoarthritis. @*Conclusions@#Arthroscopic reduction and internal fixation with cannulated screws can be good alternative options with good radiographic and clinical outcomes, convenient removal of intra-articular loose body, and low complication rates.

A case of maxilla implant overdenture using Pekkton telescopic attachment with severe alveolar bone resorption / 대한치과보철학회지

It is necessary to set the correct occlusal plane and to distribute the occlusal force uniformly considering the state of the opposing dentition during the prosthetic of the single edentulous patient with severe alveolar bone resorption. Implant supported overdenture is superior to complete denture in terms of maintenance and stability, and limited implants are used in fully edentulous patients with high alveolar bone resorption. Telescopic attachments using a newly introduced material based on poly-aryl-ether-ketone (PAEK) have the advantages of typical telescopic copping, excellent abrasion resistance, and are lighter and more economical than conventional implant overdentures. In this case, we restored maxillary arch with a implant retained overdenture using the telescopic attachment made of Pekkton and the mandible was restored with fixed implant prosthesis. Through these procedures esthetic aspects and functional outcomes were satisfactorily achieved.

Evaluation of static fracture resistances and patterns of pulpless tooth restored with poly-ether-ketone-ketone (PEKK) post / 대한치과보철학회지

PURPOSE: The purpose of present study was to investigate fracture strength and mode of failure of endodontically treated teeth restored with metal cast post-core system, prefabricated fiber post system, and newly introduced polyetherketoneketone (PEKK) post-core system. MATERIALS AND METHODS: A total of 21 mandibular premolar were randomly grouped into 3 groups of 7 each according to the post material. Group A was for metal cast post core; Group B for prefabricated glass fiber post and resin core; and Group C for milled PEKK post cores. All specimens were restored with metal crown. The fracture strength of each specimen was measured by applying a static load of 135-degree to the tooth at 2 mm/min crosshead speed using a universal testing machine. After the fracture strength measurement, the mode of failure was observed. The results were analyzed using Kruscal-Wallis test and post hoc Mann-Whitney U test at confidence interval α = .05. RESULTS: Fracture resistance of PEKK post core was lower than those of cast metal post and fiber reinforced post with composite resin core. In the aspect of fracture mode most of the root fracture occurred in the metal post core, whereas the post detachment occurred mainly in the fiber reinforced post. In the case of PEKK post core, teeth and post were fractured together. CONCLUSION: It is necessary to select appropriate materials of post for extensively damaged teeth restoration and clinical application of the PEKK post seems to require more research on improvement of strength.

Accuracy of new implant impression technique using dual arch tray and bite impression coping

PURPOSE: The purpose of this in vitro study was to evaluate the accuracy of a new implant impression technique using bite impression coping and a dual arch tray. MATERIALS AND METHODS: Two implant fixtures were placed on maxillary left second premolar and first molar area in dentoform model. The model with two fixtures was used as the reference. The impression was divided into 2 groups, n=10 each. In group 1, heavy/light body silicone impression was made with pick up impression copings and open tray. In group 2, putty/light body silicone impression was made with bite impression copings and dual arch tray. The reference model and the master casts with implant scan bodies were scanned by a laboratory scanner. Surface tessellation language (STL) datasets from test groups was superimposed with STL dataset of reference model using inspection software. The three-dimensional deviation between the reference model and impression models was calculated and illustrated as a color-map. Data was analyzed by independent samples T-test of variance at α=.05. RESULTS: The mean 3D implant deviations of pick up impression group (group 1) and dual arch impression group (group 2) were 0.029 mm and 0.034 mm, respectively. The difference in 3D deviations between groups 1 and 2 was not statistically significant (P=.075). CONCLUSION: Within limitations of this study, the accuracy of implant impression using a bite impression coping and dual arch tray is comparable to that of conventional pick-up impression.

Full mouth rehabilitation of severely worn dentition with implants and removable partial dentures / 대한치과보철학회지

Excessive tooth wear can lead to decrease in occlusal vertical dimension and can cause pathological changes in the oral environment and masticatory system. When recovering occlusal vertical dimension and occlusion, accurate diagnosis and analysis are essential. This clinical case describes a 75-year-old woman with severely worn dentition due to loss of the posterior support. Full mouth rehabilitation with occlusal vertical dimension increment was planned. Clinical and radiographic examinations, occlusal vertical dimension evaluation, and diagnostic wax-up were performed and patient adaptability was evaluated using provisional restorations. As for definitive restoration, considering economic condition of the patient, removable partial denture was fabricated and solitary implants were placed in the mandibular left and right posterior region to increase support and retention of the removable partial denture. During one year of follow-up, functional and esthetic outcomes were observed satisfactory.

Full mouth rehabilitation of a patient with worn dentition and loss of posterior support by vertical dimension reestablishment: a clinical report / 대한치과보철학회지

Excessive teeth wear may result in the complications such as esthetic problems, hypersensitivity, and loss of vertical dimension. This clinical report focuses on the causes of severely worn dentition and the full-mouth rehabilitation of a patient with rheumatoid arthritis for 20 years. An interview, clinical and radiological examinations were performed to analyze the causes and decide the treatment plan. After delivery of the final prostheses, a night guard was used to protect the restorations and temporomandibular joints. The patient was satisfied esthetically and functionally.

Full mouth rehabilitation of severely worn dentition using posterior implants: a clinical report

This clinical report focuses on the treatment of a patient with esthetic and functional impairments due to severe worn dentition. Absence of posterior support for a prolonged period require comprehensive prosthetic restoration. Accurate clinical and radiographic examinations, diagnostic wax-up, and occlusal vertical dimension evaluation were performed and the degree of patient adaptability was evaluated using an interim restoration. After 8 weeks of stabilization with interim restoration and confirmation of absence of any abnormal findings, definitive prostheses were fabricated. Satisfactory functional and esthetic outcomes were observed after 6 months of follow-up.

The Expression Of Mmp-2, Mmp-3, Mmp-10, Mmp-13 In Squamous Cell Carcinoma Of The Tongue

Matrix metalloproteinase(MMP) is the proteolytic enzyme of the extracellular matrix. MMPs play a role in the invasion and metastasis of malignant tumor, but it is not known whether the expression of MMPs in squamous cell carcinoma of the tongue is related to the prognostic factors of this tumor. In this study, 32 paraffin-embedded tumor specimens were examined immunohistochemically using monoclonal antibodies of MMP-2, MMP-3, MMP-10 and MMP-13. The possible relationships between the expressions of the MMPs and TNM staging, the differentiation of tumor cells, size of tumor mass and lymph node metastasis were anlaysed statistically. The results were as follows. 1. The expression of MMP-2 increased according to TNM staging (P < 0.05) and lymph node metastasis (P < 0.05) and the expression of MMP-2 was not affected by the differentiation of tumor cells or tumor size. 2. The expression of MMP-3 increased with increasing tumor size (P < 0.05). However it was not related to TNM staging, the differentiation of tumor cells or lymph node metastasis. 3. The expression of MMP-10 was unrelated to TNM staging, differentiation of tumor cells, lymph node metastasis or tumor size. 4. The expression of MMP-13 increased as tumor size increased (P < 0.05). However it was not related to TNM staging, the differentiation of tumor cells or lymph node metastasis. We concluded that the expression patterns of MMP-2, MMP-3, and MMP-13 may play a role in the diagnosis, treatment plan and prognostic evaluation of malignant tumors of the tongue.

Shear bond strength and debonding failure mode of ceramic brackets according to the surface treatment of porcelain / 대한치과교정학회지

The purpose of this study was to evaluate the shear bond strength and failure mode of ceramic brackets according to the surface treatment of porcelain. Sixty porcelain samples were randomly divided into six groups of ten samples. Then they were treated as follows: Group 1(silane only), Group 2(etching + silane), Group 3(stone + silane), Group 4 (sandblasting + silane), Group 5(stone + etching + silane), Group 6(sandblasting + etching + silane) After surface treatment of porcelain, sixty Transcend 6000 brackets were bonded to the prepared porcelain surface and they were stored in 37 degrees C saline for 24 hours. An Instron universal testing machine was used to test the shear bond strength of ceramic brackets to porcelain. After debonding, bases of ceramic brackets and porcelain surfaces were examined under scanning electron microscope(SEM) to determine failure mode. Statistical analysis of the data was carried out with one-way ANOVA and Duncan's multiple range test. The results were as follows: 1. The shear bond strength of surface-treated groups 2 to 6 was higher than that of only silane-treated group 1, and there was statistical significance. (P0.05) As a conclusion we can have a clinically adequate bond strength when an application of silane is done after the treatment of porcelain surface with more than one way to bond ceramic bracket on the porcelain. Also, it is considered that the sandblasting and application of silane is effective for the simplication and convenience of the treatment.