Evaluation of Vertical Bone Gain Following Alveolar Distraction Osteogenesis in the Anterior Edentulous Mandible: A Clinical Study

Aim and Objectives

To calculate the gain in bony height and volume of the distracted upper segment using an extraosseous unidirectional device to improve the retention of the future prosthesis.

Materials and Methods

Ten cases with completely or partially edentulous but severely or considerably resorbed anterior mandibles were managed by vertical alveolar distraction osteogenesis. All the patients were evaluated preoperatively, intraoperatively and post-operatively for various parameters clinically and radiographically i.e. on OPG, lateral cephalogram and on CT scan, at different time intervals. In all cases there was increase in vertical bone height.

Results

The study showed mean vertical bone gain (VBG) on OPG as 8.2 mm. The mean VBG on lateral cephalogram was 8.1 mm. The mean VBG on CT scan at right canine was 8.35 mm, at left canine was 8.2 mm and at midline was 8.27 mm.

Conclusion

Alveolar distraction osteogenesis is a predictable method for restoring alveolar ridges prior to implant placement or prosthesis. Distraction osteogenesis is ideally suited for recreating missing tissue in the anterior esthetic zone by increasing vertical bone height as well as good width and soft tissue growth.     

Designing a novel visible-light-driven heterostructure Ni–ZnO/S-g-C3N4 photocatalyst for coloured pollutant degradation

In this study, photocorrosion of ZnO is inhibited by doping Ni in the ZnO nanostructure and electron–hole recombination was solved by forming a heterostructure with S-g-C₃N₄. Ni is doped into ZnO NPs from 0 to 10% (w/w). Among the Ni-decorated ZnO NPs, 4% Ni-doped ZnO NPs (4NZO) showed the best performance. So, 4% Ni–ZnO was used to form heterostructure NCs with S-g-C₃N₄. NZO NPs were formed by the wet co-precipitation route by varying the weight percentage of Ni (0–10% w/w). Methylene blue (MB) was used as a model dye for photocatalytic studies. For the preparation of the 4NZO-x-SCN nanocomposite, 4NZO NPs were formed in situ in the presence of various concentrations of S-g-C₃N₄ (10–50% (w/w)) by using the coprecipitation route. The electron spin resonance (ESR) and radical scavenger studies showed that O₂⁻ and OH free radicals were the main reactive species that were responsible for MB photodegradation.

Ni-doped ZnO/S-g-C₃N₄ nanocomposites were formed as a novel heterostructure photocatalyst.     

Correlation of Molecular Markers in High Grade Gliomas with Response to Chemo-Radiation

Background: The standard of care in high grade glioma (HGG) is maximal safe surgical resection followed by adjuvant radiotherapy (RT) with/without chemotherapy. For anaplastic gliomas, studies have shown use of procarbazine, lomustine, vincristine (PCV) improves overall survival (OS) and progression free survival (PFS). Currently, there is substantial evidence that molecular markers strongly predict prognosis and response to treatment. Methods: Between January 2016 to January 2018, 42 patients were accrued and followed up till April 2019. The primary end points were to correlate molecular markers with response to therapy in terms of OS and PFS in HGG. The secondary end point was to evaluate frequency of 1p/19q codeletion, IDH 1 mutation, ATRX deletion and p53 in HGG patients. Results: The median age was 46 years (range 18-67) with M:F ratio 30:12. The frequency of IDH1 mutation,1p/19q codeletion, p53 mutation and ATRX mutation were 42.8%, 16.6%, 42.8% and 14.2% respectively. All the seven patients with 1p/19q codeletion had IDH1 mutation. Median follow up was 22 months. The 20-months PFS for different mutations were as follows; IDH1-mutated vs wild type: 53.6% vs 29.8%; p-0.035, 1p/19q codeleted vs non-codeleted: 85.7% vs 62.3%; p-0.011, p53 wild type vs mutated 32.1% vs 35.6%; p-0.035 and ATRX lost vs retained: 55.6% vs 53.3%; p- 0.369. The 20-months OS for IDH1 mutated vs wild type: 82.4% vs 30.6%; p-0.014, 1p/19q codeleted vs non-codeleted: 85.7% vs 65.8%; p-0.104, p53 wild-type vs mutated 45.5% vs 73.9%; p-0.036 and ATRX lost vs retained: 100% vs 60.3%; p-0.087. Conclusion: Codeletion of 1p/19q with IDH1 mutation in HGG is associated with a significantly favourable PFS. However, larger studies with longer follow up are required to evaluate OS and PFS in all the molecular subgroups.     

Management protocols of Allergic Fungal Sinusitis

Controversy surrounds the appropriate surgical approach and the appropriate medical therapy for Allergic Fungal Sinusitis. The present prospective study aims to assess the impact of these factors on the treatment outcome of Allergic Fungal Sinusitis. In the present study 34 cases with AFS were randomized into one of 3 methods of post operative therapy i.e. systemic itraconazole (group A, n=11), topical steroids (group B, n=12) and nasal alkaline douches only (group C, n=11). Outcome was assessed at 6 months post-operative by the Kupferberg grading system for assessment of nasal and sinus mucosa. Grade ‘3’ mucosal disease was defined as recurrence. Complete pre-operative opacification of sphenoid and frontal sinus was a predictor of poorer outcome. Postoperative systemic itraconazole therapy demonstrated a trend towards a better outcome but was not statistically significant. Larger trials are required to conclusively evaluate the merit of various post-operative treatment regimens for AFS.     

生物体视学中外联合双语教学实践与启发

结合2006和2007年研究生生物体视学中外联合培训班授课实践,探讨高等医学院校研究生开设生物体视学课程的现实意义,分析本次培训班授课实践给双语教学带来的启发.     

Mandibular involvement in oral cancer

It is difficult to predict the tumour invasion into the mandible by oral cancer pre-operatively, and consequently the decision to preserve or sacrifice the mandible is largely individualistic. The present study of 44 cases analyses the reliability of pre-operative parameters to assess mandibular involvement. Clinical, radiological and scintigraphic features have been compared with the detailed histology of the bone. This study confirms the usefulness of superior marginal resections in lesions which are close to but not involving the mandible, as well as for superficial lesions which are actually seen to involve the mandible but their CT and bone scans are negative for tumour invasion.     

Role of prophylactic antibiotics in surgery for advanced head and neck cancer.

Four regimens of prophylactic antibiotics were utilized in 122 consecutive patients of stages III and IV carcinoma of the upper aero-digestive tract undergoing major resections in a randomized single-blind study. Ampicillin, gentamicin, cephalexin and metronidazole were used in different combinations for periods of 5 or 10 days. A cephalexin-metronidazole protocol for 10 days was associated with lowest post-operative infection rate. Oral-oropharyngeal resection and use of pectoralis major myocutaneous flap were the most important factors contributing to infection.     

Primary neuroendocrine carcinoma of the skin arising from the post aural region.

Neuroendocrine carcinoma of the skin is an uncommon neoplasm. A case of one such tumour in the head and neck region is being presented. This case is the youngest known patient. The literature has been reviewed. The current concepts in diagnosis and management of this tumour are discussed.     

Craniofacial resection for lesions involving anterior base of skull

Craniofacial resection represents a major advance in the surgical treatment of tumours of the paranasal sinuses. It allows wide exposure of the complex anatomical structures at the base of skull permitting monobloc tumour resection. The development of computerised tomography has improved patient selection for surgery. The present study analyses results of craniofacial resection in 30 patients, 19 of whom had malignant tumours. Fourteen of these cases are disease-free after periods of 6 to 36 months. Eleven other patients had extensive benign lesions. A satisfactory reduction of proptosis and relief from other symptoms was obtained in all cases in the benign group. Craniofacial resection was thus found to give excellent results with low morbidity in malignant lesions and can also be adapted for benign tumours of anterior skull base.