Incorporation of sol-gel bioactive glass into PLGA improves mechanical properties and bioactivity of composite scaffolds and results in their osteoinductive properties.

In this study, 3D porous bioactive composite scaffolds were produced and evaluated for their physico-chemical and biological properties. Polymer poly-L-lactide-co-glycolide (PLGA) matrix scaffolds were modified with sol-gel-derived bioactive glasses (SBGs) of CaO-SiO2-P2O5 systems. We hypothesized that SBG incorporation into PLGA matrix would improve the chemical and biological activity of composite materials as well as their mechanical properties. We applied two bioactive glasses, designated as S2 or A2, differing in the content of SiO2 and CaO (i.e. 80 mol% SiO2, 16 mol% CaO for S2 and 40 mol% SiO2, 52 mol% CaO for A2). The composites were characterized for their porosity, bioactivity, microstructure and mechanical properties. The osteoinductive properties of these composites were evaluated in human bone marrow stromal cell (hBMSC) cultures grown in either standard growth medium or treated with recombinant human bone morphogenetic protein-2 (rhBMP-2) or dexamethasone (Dex). After incubation in simulated body fluid, calcium phosphate precipitates formed inside the pores of both A2-PLGA and S2-PLGA scaffolds. The compressive strength of the latter was increased slightly compared to PLGA. Both composites promoted superior hBMSC attachment to the material surface and stimulated the expression of several osteogenic markers in hBMSC compared to cells grown on unmodified PLGA. There were also marked differences in the response of hBMSC to composite scaffolds, depending on chemical compositions of the scaffolds and culture treatments. Compared to silica-rich S2-PLGA, hBMSC grown on calcium-rich A2-PLGA were overall less responsive to rhBMP-2 or Dex and the osteoinductive properties of these A2-PLGA scaffolds seemed partially dependent on their ability to induce BMP signaling in untreated hBMSC. Thus, beyond the ability of currently studied composites to enhance hBMSC osteogenesis, it may become possible to modulate the osteogenic response of hBMSC, depending on the chemistry of SBGs incorporated into polymer matrix.

Evaluation of pain regression in patients with temporomandibular dysfunction treated by intra-articular platelet-rich plasma injections: a preliminary report.

OBJECTIVE: The objective of this study was to evaluate the regression of temporomandibular pain as a result of intra-articular injections of platelet-rich plasma (PRP) to patients with temporomandibular joint dysfunction previously subjected to prosthetic treatment. MATERIALS AND METHODS: The baseline study material consisted of 10 patients, both males and females, aged 28 to 53 years, previously treated due to painful temporomandibular joint dysfunction using occlusal splints. All patients were carried out to a specialist functional assessment of the dysfunction using the Polish version of the RDC/TMD questionnaire axis I and II. Intra-articular injections were preceded by a preparation of PRP. The injection sites were determined by the method used during arthroscopic surgical procedures. Following aspiration, 0.5 mL of plasma was injected into each temporomandibular joint. RESULTS: The comparison of the intensity of pain during all examinations suggests a beneficial effect of the procedure being performed as the mean VAS score was 6.5 at examination I, 2.8 at examination II, and 0.6 at examination III. CONCLUSION: Application of the intra-articular injections of platelet-rich plasma into the temporomandibular joints has a positive impact on the reduction of the intensity of pain experienced by patients treated for temporomandibular joint dysfunction.

Differential diagnostics of pain in the course of trigeminal neuralgia and temporomandibular joint dysfunction.

Chronic oral and facial pain syndromes are an indication for intervention of physicians of numerous medical specialties, while the complex nature of these complaints warrants interdisciplinary diagnostic and therapeutic approach. Oftentimes, lack of proper differentiation of pain associated with pathological changes of the surrounding tissues, neurogenic pain, vascular pain, or radiating pain from idiopathic facial pain leads to improper treatment. The objective of the paper is to provide detailed characterization of pain developing in the natural history of trigeminal neuralgia and temporomandibular joint dysfunction, with particular focus on similarities accounting for the difficulties in diagnosis and treatment as well as on differences between both types of pain. It might seem that trigeminal neuralgia can be easily differentiated from temporomandibular joint dysfunction due to the acute, piercing, and stabbing nature of neuralgic pain occurring at a single facial location to spread along the course of the nerve on one side, sometimes a dozen or so times a day, without forewarning periods. Both forms differ significantly in the character and intensity of pain. The exact analysis of the nature, intensity, and duration of pain may be crucial for the differential diagnostics of the disorders of our interest.

NADPH oxidase and uncoupled nitric oxide synthase are major sources of reactive oxygen species in oral squamous cell carcinoma. Potential implications for immune regulation in high oxidative stress conditions.

The development of cancer is associated with high oxidative stress and at the same time with immune system activation. Tumors develop efficient mechanisms of protection against the immune response, which allow them to escape the immune surveillance. Simultaneously, key events in the process of carcinogenesis are related to oxidative stress. The relationship between the two remains unknown. Novel understanding of oxidative stress shows that discrete changes of activities of certain enzyme systems such as NADPH oxidases or nitric oxide synthases may be more important than the overall balance of production and removal of reactive oxygen species. Such imbalance of nitric oxide and superoxide production could modify inflammation and immune regulation. We studied superoxide anion production (by lucigenin enhanced chemiluminescence - 5 microM), NADPH oxidase activity and nitric oxide synthase (NOS) dysfunction. In parallel mRNA expression of immunomodulatory markers such as FoxP3 (T regulatory cell marker), CCR6 (mucosal homing effector T cell marker) and CD85j (NK cell/CD8 T cell Ig-like MHC class I inhibitory receptor) was determined. Basal superoxide production and NADPH oxidase activity are increased in oral squamous cell carcinoma. Tumor superoxide production was inhibited by NADPH oxidase inhibitor apocynin and by NOS inhibitor L-NAME. This indicates, for the first time, that oral squamous cell carcinoma is characterized by dysregulated nitric oxide synthase, which apart from increased NADPH oxidase activity contributes to oxidative stress and may be related to the immuno-pathology of these tumors. Studied tumors were infiltrated by CCR6+, but showed lower expression of both CD85j and FoxP3 mRNA. Finally, the CD85j mRNA expression was inversely correlated to oxidative stress parameters. These preliminary studies indicate that tumor oxidative stress, related to NADPH oxidase activity and NOS activity could be related to immune responses to cancer, thus therapeutic modification of oxidative stress, which could include the correction of NOS dysfunction, could facilitate immune surveillance.

Pitanguy's method of protruding ear correction from our own experience: review of 80 cases.

A recent review of the literature revealed more than 20 methods of correction of protruding ears. Pitanguy's cartilage island flap technique is still not widespread. However, it is extraordinarily versatile and effective from our own experience. The aim of this study is to present our own experience in the correction of prominent ears using this method. According to Pitanguy's cartilage island flap technique, 80 patients were operated on at the Private Plastic Surgery Clinic from 1992 to 1999. There were 45 (56%) female and 35 (44%) male patients, aged from 9 to 37 years (22 years on average). All procedures were performed under local anesthesia. In the follow-up period of 1 to 8 years the final aesthetic results were estimated as very good in 68 (85%) patients and good in 12 (15%) patients. Early complications in the form of bleeding occurred in three (3.75%) patients. Asymmetry in the ears' position was qualified as a late complication and occurred in four (5%) patients.

General anesthesia via tracheosubmental intubation from our own experience.

In our department from 1995 to 1998, 30 patients were operated on under general anesthesia via tracheosubmental intubation (TSI). No local or general complications were observed. Operating in the field free from the intubation tube is very comfortable for a surgeon, while for an anesthesiologist the safety of the tube and efficiency of ventilation are very important. TSI, as a technically simple, safe, and efficient procedure, is extremely helpful in the surgical treatment of patients with simultaneous multifragmentaric and comminuted fractures of the maxilla and mandible, and in orthognathic and aesthetic plastic surgery of the face, where assessment of facial symmetry and occlusion is especially important.

Actinomycotic osteomyelitis of the mandible: review of 15 cases.

The authors have analysed 15 cases of actinomycotic osteomyelitis of the mandible. Primary actinomycotic inflammation of the mandible was diagnosed in nine patients, secondary in six patients (following fracture or resection of the mandible). The diagnosis was established on the basis of the clinical examination confirmed by bacteriological and/or histopathological tests. The basic method of treatment was antibiotic therapy of long duration. Surgical treatment was performed in all patients. Twelve of fifteen patients who had received the therapy and proved asymptomatic for 1 year to 23 years were recognized to be cured of the disease. In three patients, a single recurrence of the disease was observed after 1.5-2 months.

Immunohistochemical demonstration of S100 protein in malignant melanomas of the facial skin and oral cavity.

Immunohistochemical demonstration of S100 protein was performed in 56 cases of malignant melanoma of the facial skin and oral cavity. The depth of invasion was measured comparatively in HE sections and in sections stained for S100 protein. Comparison of measured melanoma invasion depth in S100- and HE-stained sections revealed a deeper invasion of the tumor in S100-stained slides than in slides stained routinely with HE according to Breslow's melanoma staging procedure. A reverse relationship between the intensity of immunohistochemical staining for S100 protein and survival rate was found in both melanomas of the facial skin and oral cavity. Although the presence of S100 protein has been demonstrated previously in skin melanomas, no similar investigations concerning the oral mucosa have been performed up to now.