Characterization of tissue conditioner containing chitosan-doped silver nanoparticles / 대한치과보철학회지

Purpose@#Development of a latent antimicrobial soft liner is strongly needed to overcome a possible inflammation related with its dimensional degrade or surface roughness. Modified tissue conditioner (TC) containing chitosan-doped silver nanoparticles (ChSN) complexes were synthesized and assessed for their characterizations. @*Materials and methods@#ChSN were preliminarily synthesized from silver nitrate (AgNO3), sodium borohydride (NaBH4) as a reducing agent and chitosan biopolymer as a capping agent. Ultraviolet-visible and Fourier transform infrared spectroscopy were conducted to confirm the stable reduction of nanoparticles with chitosan. Modified TC blended with ChSN by 0 (control), 1.0, 3.0 and 5.0 % mass fraction were mechanically tested by ultimate tensile strength (UTS), silver ion elution and color stability (n=7). @*Results@#At 24 hour and 7 day storage periods, UTS values were not significant (P>.05) as compared with pristine TC (control) and silver ion was detected with the dose-dependent values of ChSN incorporated. Color stability of TC were influenced by ChSN add, with the higher doses, the significantly greater color changes (P<.05). @*Conclusion@#A stable synthesized ChSN was acquired and modified TC loading ChSN was characterized as silver ion releasing without detrimental physical property. For its clinical application, antimicrobial test, color control and multifactor investigations are still required.

Antibacterial activity and characterization of tissue conditioner containing silver-chitosan nanocomplex / 대한치과재료학회지

The objective of this work was to verify the antimicrobial effect and the characteristics of the tissue conditioner containing silver-chitosan nanocomplex at in vitro level. Nanocomplex was synthesized by the chemical reduction of silver nitrate and chitosan in aqueous solution with sodium borohydride as a reducing agent. Silver-chitosan nanocomplex was incorporated to tissue conditioner as powder to powder ratio with different weight percentage (%) of 0 (control), 1.0, 3.0, 5.0 and 7.0. The antimicrobial effect was assessed by colony forming unit in retrieved two streptococcal suspensions inoculated on specimens and cytotoxicity was measured using human gingival fibroblasts by MTS assay. Surface topography, Ag ion release and ultimate tensile strength tests were conducted for mechanical validity. The significantly reduced bacterial adhesions were observed above 5.0% loading while all of tested samples did not show cytotoxicity when compared to the control. Ag ion releases were detected with the dose-dependent of initial silver loadings with gradual decreasing over time. Modified tissue conditioner revealed similar microscopic surface textures and expressed no significant tensile strength changes (P>0.01) as compared to unmodified. Within some limitations in present study, the tissue conditioner loaded by 5.0% of silver-chitosan nanocomplex can be candidate as a novel denture biomaterial without mechanical hazards. For a clinical specification, future studies including in vivo, multi-strain or factor assays, and additional physical tests were still required.

Radiation prosthetic stents applied to oral cancer patients during the radiation therapy: case reports

Radiation prosthetic stent is defined as the customized oral devices which serve for an efficient administration of radiation dose to the affected areas or a minimizing the unnecessary irradiation to surrounding normal tissues during maxillofacial cancer radiotherapy. Since the use of stents is individualized, a close collaboration among radiotherapist, surgeon and prosthodontist is essential thereby which helps in limiting the post-therapy morbidity as well as the stable oral rehabilitation. In this report, two customized stents (bolus carrier and tongue depressing) were fabricated and applied to patient undergone irradiation for soft palate and tongue carcinoma selectively. Multidisciplinary approach can be a proper strategy and recommended for control the sequel of post-irradiation.

Radiation prosthetic stents applied to oral cancer patients during the radiation therapy: case reports

Radiation prosthetic stent is defined as the customized oral devices which serve for an efficient administration of radiation dose to the affected areas or a minimizing the unnecessary irradiation to surrounding normal tissues during maxillofacial cancer radiotherapy. Since the use of stents is individualized, a close collaboration among radiotherapist, surgeon and prosthodontist is essential thereby which helps in limiting the post-therapy morbidity as well as the stable oral rehabilitation. In this report, two customized stents (bolus carrier and tongue depressing) were fabricated and applied to patient undergone irradiation for soft palate and tongue carcinoma selectively. Multidisciplinary approach can be a proper strategy and recommended for control the sequel of post-irradiation.

Characterization and antimicrobial efficacy of Portland cement impregnated with silver nanoparticles

PURPOSE: This study investigated the effects of silver nanoparticle (SN) loading into hydraulic calcium silicate-based Portland cement on its mechanical, antibacterial behavior and biocompatibility as a novel dental bone substitute. MATERIALS AND METHODS: Chemically reduced colloidal SN were combined with Portland cement (PC) by the concentrations of 0 (control), 1.0, 3.0, and 5.0 wt%. The physico-mechanical properties of silver-Portland cement nanocomposites (SPNC) were investigated through X-ray diffraction (XRD), setting time, compressive strength, solubility, and silver ion elution. Antimicrobial properties of SPNC were tested by agar diffusion against Streptococcus mutans and Streptococcus sobrinus. Cytotoxic evaluation for human gingival fibroblast (HGF) was performed by MTS assay. RESULTS: XRD certified that SN was successfully impregnated in PC. SPNC at above 3.0 wt% significantly reduced both initial and final setting times compared to control PC. No statistical differences of the compressive strength values were detected after SN loadings, and solubility rates of SPNC were below 3.0%, which are acceptable by ADA guidelines. Ag ion elutions from SPNC were confirmed with dose-dependence on the concentrations of SN added. SPNC of 5.0 wt% inhibited the growth of Streptococci, whereas no antimicrobial activity was shown in control PC. SPNC revealed no cytotoxic effects to HGF following ISO 10993 (cell viability > 70%). CONCLUSION: Addition of SN promoted the antibacterial activity and favored the bio-mechanical properties of PC; thus, SPNC could be a candidate for the futuristic dental biomaterial. For clinical warrant, further studies including the inhibitory mechanism, in vivo and long-term researches are still required.

Characterization and antimicrobial efficacy of Portland cement impregnated with silver nanoparticles

PURPOSE: This study investigated the effects of silver nanoparticle (SN) loading into hydraulic calcium silicate-based Portland cement on its mechanical, antibacterial behavior and biocompatibility as a novel dental bone substitute. MATERIALS AND METHODS: Chemically reduced colloidal SN were combined with Portland cement (PC) by the concentrations of 0 (control), 1.0, 3.0, and 5.0 wt%. The physico-mechanical properties of silver-Portland cement nanocomposites (SPNC) were investigated through X-ray diffraction (XRD), setting time, compressive strength, solubility, and silver ion elution. Antimicrobial properties of SPNC were tested by agar diffusion against Streptococcus mutans and Streptococcus sobrinus. Cytotoxic evaluation for human gingival fibroblast (HGF) was performed by MTS assay. RESULTS: XRD certified that SN was successfully impregnated in PC. SPNC at above 3.0 wt% significantly reduced both initial and final setting times compared to control PC. No statistical differences of the compressive strength values were detected after SN loadings, and solubility rates of SPNC were below 3.0%, which are acceptable by ADA guidelines. Ag ion elutions from SPNC were confirmed with dose-dependence on the concentrations of SN added. SPNC of 5.0 wt% inhibited the growth of Streptococci, whereas no antimicrobial activity was shown in control PC. SPNC revealed no cytotoxic effects to HGF following ISO 10993 (cell viability > 70%). CONCLUSION: Addition of SN promoted the antibacterial activity and favored the bio-mechanical properties of PC; thus, SPNC could be a candidate for the futuristic dental biomaterial. For clinical warrant, further studies including the inhibitory mechanism, in vivo and long-term researches are still required.

Treatment of dental implant-related maxillary sinusitis with functional endoscopic sinus surgery in combination with an intra-oral approach

The present report describes the case of a patient who underwent maxillary sinusitis right after dental implant installation with sinus lifting. Computed tomography scan revealed a dental implant (#16) was protruded inside the right maxillary sinus and confirmed the obstruction of ostium. A symptom remission was gained with the dual approaches combined by functional endoscopic sinus surgery and an intra-oral approach. Fully recovered function and healing of sinus were identified after 10 months follow-up. We report the case of sinusitis caused by protrusion of implants with sinus floor lift procedures and propose that practitioners should be aware of the possible its complications and management.

Characterization and bacterial anti-adherent effect on modified PMMA denture acrylic resin containing platinum nanoparticles

PURPOSE: This study characterized the synthesis of a modified PMMA (Polymethyl methacrylate) denture acrylic loading platinum nanoparticles (PtN) and assessed its bacterial inhibitory efficacy to produce novel antimicrobial denture base material. MATERIALS AND METHODS: Polymerized PMMA denture acrylic disc (20 mm x 2 mm) specimens containing 0 (control), 10, 50, 100 and 200 mg/L of PtN were fabricated respectively. The obtained platinum-PMMA nanocomposite (PtNC) was characterized by TEM (transmission electron microscopy), SEM/EDX (scanning electron microscope/energy dispersive X-ray spectroscopy), thermogravimetric and atomic absorption spectrophotometer analysis. In antimicrobial assay, specimens were placed on the cell culture plate, and 100 microL of microbial suspensions of S. mutans (Streptococcus mutans) and S. sobrinus (Streptococcus sobrinus) were inoculated then incubated at 37degrees C for 24 hours. The bacterial attachment was tested by FACS (fluorescence-activated cell sorting) analysis after staining with fluorescent probe. RESULTS: PtN were successfully loaded and uniformly immobilized into PMMA denture acrylic with a proper thermal stability and similar surface morphology as compared to control. PtNC expressed significant bacterial anti-adherent effect rather than bactericidal effect above 50 mg/L PtN loaded when compared to pristine PMMA (P=.01) with no or extremely small amounts of Pt ion eluted. CONCLUSION: This is the first report on the synthesis and its antibacterial activity of Pt-PMMA nanocomposite. PMMA denture acrylic loading PtN could be a possible intrinsic antimicrobial denture material with proper mechanical characteristics, meeting those specified for denture bases. For clinical application, future studies including biocompatibility, color stability and warranting the long-term effect were still required.

Lipoma with Extraoral Swelling in the Labial Vestibule: Report of a Case

Expansile dentigerous cyst invading the entire maxillary sinus: a case report

Reported cases of a large dentigerous cyst involving the whole maxillary sinus are uncommon. A 22-year-old female patient suffering from swelling of the right infraorbital area and cheek with dull pain was referred to our department. Findings on computed tomography (CT) and magnetic resonance imaging (MRI) revealed a huge mass containing a displaced maxillary third molar involving the right maxillary sinus as a whole, with partial erosion of the posterior sinus cortical bone. Under general anesthesia, the mass was enucleated using the Caldwell-Luc approach, and, following histopathological analysis, was diagnosed as a dentigerous cyst. The case was followed for a period of seven years, and no evidence of sinus infection or recurring cyst formation was observed during that time.

In vitro antimicrobial effect of the tissue conditioner containing silver nanoparticles

PURPOSE: The aim of this study was to identify in vitro antimicrobial activity of the tissue conditioner containing silver nanoparticles on microbial strains, Staphylococcus aureus, Streptococcus mutans and Candida albicans. MATERIALS AND METHODS: Experimental disc samples (20.0x3.0 mm) of tissue conditioner (GC Soft-Liner, GC cooperation, Tokyo, Japan) containing 0.1 - 3.0% silver nanoparticles (0%: control) were fabricated. Samples were placed on separate culture plate dish and microbial suspensions (100 microL) of tested strains were inoculated then incubated at 37degrees C. Microbial growth was verified at 24 hrs and 72 hrs and the antimicrobial effects of samples were evaluated as a percentage of viable cells in withdrawn suspension (100 microL). Data were recorded as the mean of three colony forming unit (CFU) numerations and the borderline of the antimicrobial effect was determined at 0.1% viable cells. RESULTS: A 0.1% silver nanoparticles combined to tissue conditioner displayed minimal bactericidal effect against Staphylococcus aureus and Streptococcus mutans strains, a 0.5% for fungal strain. Control group did not show any microbial inhibitory effect and there were no statistical difference between 24 hrs and extended 72 hrs incubation time (P > .05). CONCLUSION: Within the limitation of this in vitro study, the results suggest that the tissue conditioner containing silver nanoparticles could be an antimicrobial dental material in denture plaque control. Further mechanical stability and toxicity studies are still required.

Treatment of the Trimalleolar Fracture Using Posterolateral Approach: Minimum 2-year Follow Up Results

PURPOSE: To analyze the long term follow up results of treatment with posterolateral approach and to investigate its usefulness in the patients of trimalleolar fracture with posterior fragment which is above 25% of articular involvement. MATERIALS AND METHODS: There were 34 cases of trimalleolar fracture in our hospital from May 2004 to April 2008. We investigated 20 patients who underwent operation with the posterolateral approach and over-2 years follow up cases. The mean follow up period was 34 (24~58) months. Preoperative posterior malleolar fragment involved above 25% of articular surface in all cases and displaced more than 2 mm in 11 cases. We analyzed the radiologic type of posterior malleolar fragments and evaluated the function and pain through AOFAS score and complications. RESULTS: All cases showed primary union at mean 13.1 weeks. The complications are that partial ankylosis result of soft tissue contracture is seen in 2 cases (10%) and post-traumatic arthritis is seen in 1 cases (5%) and 17 cases (85%) of all patients are showed excellent AOFAS score. CONCLUSION: The posterolateral approach is a valuable method because that it enables us to easily reduction and internal fixation of the posterior malleolus and lateral malleolus at one time and the results are satisfied for a long time follow up.

Percutaneous Cannulated Screw Fixation of Fifth Proximal Metatarsal Stress Fracture in Athletes / 대한스포츠의학회지

The purpose of this study was to know utility of percutaneous cannulated screw fixation of fifth proximal metatarsal stress fractures in athletes by assessment of radiological and clinical outcome. This study examined clinical and radiological union time of eleven cases of percutaneous screw fixation, which used the 4.0 mm cannulated screw, of fifth proximal metatarsal stress fracture in athletes. Type I of Torg classification is 7 cases, type II is 3 cases and type III is 1 case. All the cases showed fracture union, and all the patients resumed their athletics at the final follow-up. None of the cases complained of refracture or pain around where they had surgery, and visual analogue scale of pain, and American Orthopedic Foot and Ankle Society score was 0.73 and 93.4. The results of the study confirm that percutaneous screw fixation, which used the cannulated screw, of fifth proximal metatarsal stress fracture would help athletes resume their athletics in early stages.

Distal Tibiofibular Synostosis after Open Reduction and Internal Fixation in a Military Soldier (A Case Report) / 대한족부족관절학회지

The scanty literature on distal tibiofibular synostosis includes descriptions of relatively few specific complaints. Here we report a case of a 24-year-old young soldier who sustained a left ankle lateral malleolar fracture about 6 months ago and was initially treated by the open reduction and internal fixation with plate & screw. But 6 months later, he suffered from an vague ankle pain, each time the symptoms occurred right after an active ambulation, ankle dorsiflexion, especially when he had exercised aggressively. The radiographs revealed that there was a mature distal tibiofibular synostosis. We treated the patient with surgical excision of synostosis. Post-operative condition was satisfied to all concern and the result was found to be excellent during one-year follow-up.

Macrodystrophia Lipomatosa of the Foot (A Case Report) / 대한족부족관절학회지

Macrodystrophia lipomatosa is a congenital macrodactyly characterized by progressive overgrowth of all the mesenchymal elements of a digit or digits with a disproportionate increase in the fibroadipose tissue. We reported a case of macrodystrophia lipomatosa of the foot, which is a rare case, and reviewed the literatures.

The Primary Reverse Total Shoulder Arthroplasty for Post-septic Destroyed Shoulder: A Case Report

PURPOSE: We report here on a solution for the case of a 71 year old lady with cartilage destruction in the left shoulder and the loss of the rotator cuff secondary to post-septic arthritic sequelae. MATERIALS AND METHODS: After thorough laboratory, clinical and radiological investigation of the patient to rule out any foci of active infection, we contemplated performing reverse total shoulder arthroplasty as a primary procedure. RESULTS: At 22 months follow up, the patient had an excellent result according to the UCLA and ASES scales. CONCLUSION: Reverse total shoulder arthroplasty seems to be an efficient procedure to improve pain and function in the post-septic shoulder accompanying severe rotator cuff injury.

Management of Cyst on Anterior Tibia following Cementless Total Knee Arthroplasty: Case Report / 대한정형외과학회잡지

There are no reports of the occurrence of a cyst in the anteromedial side of the proximal tibia after cementless total knee arthroplasty in the Korean literature. The authors encountered 2 cases with a cyst, in whom the pain improved after cemented total knee revision arthroplasty. We report these cases with a review of the relevant literature.

Cephalometric differences in obstructive sleep apnea between obese and non-obese Korean male patients / 대한치과교정학회지

OBJECTIVE: The purpose of this study was to compare the cephalometric measurements of obese and non-obese Korean male patients with obstructive sleep apnea syndrome (OSA). METHODS: Eighty-seven adults who had visited the Sleep Disorder Clinic Center in Keimyung University, Daegu, Korea were examined and evaluated with polysomnography (PSG) and lateral cephalogram. They were divided into 4 groups (non-obese simple snorers, obese simple snorers, non-obese OSA patients, obese OSA patients) according to AHI (Apnea-Hypopnea Index) and BMI (Body Mass Index). RESULTS: The obese OSA group had the highest AHI among the 4 groups. The non-obese OSA group had a significantly steeper mandibular angle and shorter tongue length than the obese OSA group. The hyoid bone of the obese OSA group was positioned anterior and inferior as compared with the non-obese OSA group. Multiple regression analysis showed that tongue length in the obese OSA group and retroposition of hyoid bone in the non-obese OSA group were significant determinants for the severity of AHI. CONCLUSIONS: From a cephalometric point of view, the obese and non-obese pateints with OSA may be characterized by different pathogeneses. Therefore, they have to be managed by individualized treatment. For the obese OSA patients, weight control must be advised as a first choice and for the non-obese OSA patients, oral appliance, nasal CPAP, UPPP and others could be chosen according to the obstructive sites.

Neuroprotection for Acute Spinal Cord Injury: Comparison of Simvastatin and Atorvastatin / 대한정형외과학회잡지

PURPOSE: To evaluate the neuroprotective effect of statins after a spinal cord injury. MATERIALS AND METHODS: Twenty four Sprague Dawley rats had a spinal cord injury at T9/10 using an Ohio State University (OSU) impactor. The animals were randomized to receive either simvastatin, atorvastatin, or saline with oral gavage everyday for 7 days. A behavioral outcome assessment was performed on days 2, 4 and 7, and then every week using the Basso, Bresnahan, and Beattie (BBB) score and subscore. The animals also underwent sensory threshold testing using a von Frey monofilament device. The animals were sacrificed at the end of 6 weeks and a spinal cord specimen was harvested. Histology and immunohistochemistry were performed to measure the areas of white and gray matter, and the sparing of oligodenrocytes. RESULTS: For the animals treated with simvastatin, atorvastatin and saline, the mean BBB scores at 6 weeks post-injury was 13.2+/-0.1, 11.8+/-0.5, and 11.3+/-0.2 and the BBB subscores were 9.2+/-1.1, 4.8+/-1.8 and 4.4+/-1.4 respectively (p<0.05). The areas of white matter at the lesion epicenter were 0.78+/-0.05, 0.5+/-0.18 and 0.41+/-0.03 mm2 in the simvastatin, atorvastatin and saline groups respectively, and the number of spared oligodendrocytes was significantly higher in the simvastatin treated animals (p<0.05). CONCLUSION: The simvastatin treatment improved the behavior and histological sparing of the spinal cord after an acute spinal cord injury in rats.

The Selection of Exercise Stress Test in Hemiplegic Patients

OBJECTIVE: To suggest the standard tool for the selection of exercise stress tests (EST) by analysis of the initial evaluation factors affecting EST. METHOD: Twenty-two hemiplegic patients carried out treadmill, arm and bicycle ergometer ESTs. Treadmill EST using modified Harbor protocol was performed without taking off AFO. The velocity of the arm and bicycle ergometer was set in 50 rpm, and the resistance was increased up to 5 W at each stage. Each EST was completed at 80% of maximal heart rate. RESULTS: Brunnstrom stage of lower extrimity, Medical Research Council (MRC) scores [hip flexor, knee extensor, finger flexor] and standing balance of twelve patients completing treadmill EST were superior to those of failed group (p<0.05). Twelve patients completing bicycle ergometer EST showed significant differences in MRC scores [hip flexor, knee extensor] and sitting balance (p<0.05). Brunnstrom stage of lower extremity hip flexor and knee extensor power contributed mostly to the completion of treadmill EST (p<0.01). The completion of bicycle ergometer EST was mostly dependent on hip flexor and knee extensor power (p<0.01). CONCLUSION: For bicycle ergometer EST, hip flexor and knee extensor power should be higher than 3 and 4, respectively. Treadmill EST can be suggested when Brunnstrom stage of lower extremity, hip flexor and knee extensor power are above 4, 4 and 3, respectively. The completion rate of treadmill EST can be increased when standing balance ability and Brunnstrom hand score higher than 4 and 2, respectively.