Evaluation of the biocompatibility, antibacterial and anticancer effects of a novel nano-structured Fe-Mn-based biodegradable alloys in-vitro study.

Scientific backgrounds: Development of nanostructured biodegradable alloys has generated a great deal of interest in the recent years as they offer promising bioactive materials for reconstruction of bony defects following traumatic fractures or surgical excision of tumors. Objectives: The aim of the current study was to investigate the biocompatibility of Iron-Manganese -based alloys (Fe-Mn) with addition of copper (Cu), Tungsten (W) and cobalt (Co) to obtain 3 different alloys namely, Fe-Mn-Cu, Fe-Mn-W, and Fe-Mn-Co on normal oral epithelial cell line,and their possible anticancer effect on MG-63: osteosarcoma cell line. Materials and methods: The sulforhodamine B (SRB) assay was used to assess cell viability percentage of both cell lines after exposure to discs of the proposed experimental alloys. Moreover, the antibacterial effect of such alloys against Escherichia coli (E. coli) was tested using disc diffusion susceptibility (Kirby-Bauer method) and colony suspension method. Results: The cell viability percentage of oral epithelial cell line showed a significant increase in all the experimental groups in comparison to the control group. The highest percentage was observed in Fe-Mn-Co group, followed by Fe-Mn-W then Fe-Mn-Cu, at 24 and 72-h intervals, respectively. While the cell viability percentage of osteosarcoma cell line showed significant increase in all the experimental groups at 24-h intervals, it showed a significant drop in all the study groups at 72-h intervals. The lowest percentage was observed in Fe-Mn-Cu group, followed by Fe-Mn-W then Fe-Mn-Co. Moreover, all the examined study groups didn't show any inhibition zones against E. coli reference culture. Conclusions: The novel nanostructured biodegradable Fe-Mn-Cu, Fe-Mn-W, and Fe-Mn-Co metal alloys exhibit good biocompatibility on oral epithelial cell lines with the enhancement of cell proliferation in a time-dependent manner that favors bone regeneration. On the other hand, all the alloys manifested possible anticancer activity against MG-63: osteosarcoma cell line. Furthermore, our study sheds the light on the importance of Co, W and Cu as promising alloying elements. However, the antibacterial activity of the examined alloys is still questionable. Clinical relevance: The novel nanostructured biodegradable Fe-Mn-Cu, Fe-Mn-W, and Fe-Mn-Co metal alloys offer promising bioactive materials for reconstruction of bony defects following traumatic fractures or surgical excision of tumors, In addition, they could be excellent alternatives for undegradable or non-resorbable alloys that are commonly used. Moreover, they could be used as beneficial 3D printing materials to obtain patient-specific medical implants that favor bone regeneration in addition to manufacturing of plates and screws suitable for fracture fixation.

Functional outcomes after using the glenoid fossa as a fixed anchorage for the temporomandibular joint discopexy in patients with disc displacement without reduction.

The aim of the present study was to evaluate the use of the glenoid fossa as an anchorage for the temporomandibular joint (TMJ) disc repositioning in patients with a disc displacement (DD) without reduction. A prospective case series study included patients with DD without reduction. According to the Wilkes staging system for the TMJ internal derangement, preoperative magnetic resonance imaging (MRI) scans and clinical examinations determine the stage of the DD. The discopexy treatment consists of combined endaural/preauricular incision on the tragus, and freeing the anteromedial displaced disc from its attachments. An intra bony hole was drilled 2 mm away from the postero-lateral lip of the glenoid fossa and perpendicular to it. The disc was securely fixed to the roof of the fossa via a Prolene 0 suture in a double-pass suture fashion. The functional assessment was based on the pain visual analogue scale (VAS) and measurements of the maximum inter-incisal opening (MIO) after 1, 6, 12, and 18 months. P values ≤ 0.05 were considered significant. Thirteen of 25 joints were diagnosed with Wilkes stage III. The mean VAS score significantly decreased to 2.2 ± 1.0 and the MIO also significantly improved with a mean of 35.9 ± 3.5 mm after 18 months (P < 0.001). The rest of the cases (12 joints) were diagnosed with Wilkes stage IV, and the VAS score decreased to 1.6 ± 0.7. The MIO increased to 34.2 ± 3.3 mm at the end of the follow-up (P < 0.001). Within the limitations of the study, it seems that using the glenoid fossa as anchorage for the TMJ disc might have some clinical relevance and therefore might be taken into consideration whenever it is deemed appropriate.

A retrospective analysis of 5-year post surgery recurrence of N0 neck and the role of methylene blue in sentinel lymph node biopsy.

The aim of this study is to perform a retrospective analysis of the feasibility of the clinical application of SLNB using methylene blue dye (MBD) for the identification of SLN followed by frozen section biopsy to detect occult metastasis in clinically N0 necks. Hence, to know the reliability of MBD in reducing the need for extensive surgery. METHODS: We retrospectively analyzed the clinic pathological data of 48 patients with early oral cancer.The SLN identification rate (IR) was calculated in SLNB with MBD and the false-negative rate (FNR). Intra operative frozen section biopsy was done for all patients was compared with post-operative paraffin histopathology report and the prognosis of patients was analyzed. RESULTS: Analysis of the 48 SLNB cases showed that there were significant differences in SLN successful detection rate among patients with different site (p = 0.043) and clinical presentation (p = 0.007). Similar significant results (p < 0.05) were observed with intra-operative frozen and post-operative paraffin histopathology sections. SLNs were successfully detected in 37(77.1%) patients out of 48. The intra operative frozen histopathology completely matched with the post-operative paraffin histopathology showing 39 (81.2%) negative and 09 (18.8%) positive cases. A prognostic analysis of SLN detection based on 48 patients showed that the 5-year survival rate was 100%. CONCLUSION: MBD has acceptable SLN identification rate and a low FNR(false negative report) in frozen sections. Stained SLNs with no SLN metastasis are associated with disease-free survival (DFS). Hence, MBD-SLN biopsy has significantly reduced the need for extensive neck dissection in N0 neck with less morbidity.