Finite element analysis of different surgical approaches in various occlusal loading locations for zygomatic implant placement for the treatment of atrophic maxillae

The aim of this study was to compare two different types of surgical approaches, intrasinus and extramaxillary, for the placement of zygomatic implants to treat atrophic maxillae. A computational finite element simulation was used to analyze the strength of implant anchorage for both approaches in various occlusal loading locations. Three-dimensional models of the craniofacial structures surrounding a region of interest, soft tissue and framework were developed using computed tomography image datasets. The implants were modelled using computer-aided design software. The bone was assumed to be linear isotropic with a stiffness of 13.4GPa, and the implants were assumed to be made of titanium with a stiffness of 110GPa. Masseter forces of 300N were applied at the zygomatic arch, and occlusal loads of 150N were applied vertically onto the framework surface at different locations. The intrasinus approach demonstrated more satisfactory results and could be a viable treatment option. The extramaxillary approach could also be recommended as a reasonable treatment option, provided some improvements are made to address the cantilever effects seen with that approach.     

Prosthetic rehabilitation of an orbital and facial defect: a clinical report

For patients undergoing radical head and neck surgery, the deformity or physical defect adds to the agony. Rehabilitation of patients with such deformities is a challenge for the maxillofacial prosthodontist to enhance the esthetics and give psychological strength to the patient. This clinical report describes the rehabilitation, using a silicone prosthesis, of a large facial and orbital defect due to mucoepidermoid carcinoma.     

Successful surgical repair of iatrogenic pulmonary vein stenosis

Pulmonary vein stenosis can complicate ablation procedures for atrial fibrillation and often presents with severe respiratory symptoms. Described in this case report is a 21-year-old male who underwent a bilateral surgical augmentation of the pulmonary veins for severe occlusive pulmonary vein stenosis. The occluded left lower and right upper lobe veins were surgically modified to regain flow to the left atrium. Follow-up computed tomogram imaging showed patency of the veins intervened upon and an exercise test demonstrated an oxygen saturation of 98% at peak stress.This case report marks the first-ever surgical intervention for acquired pulmonary vein stenosis.     

Changes in retinal vessels related to varicocele: a pilot investigation

The aim of this study was to investigate whether retinal vasculature changes had occurred (retinal artery diameter, retinal vein diameter and artery/vein ratio) in patients with varicocele. This pilot study included 50 healthy subjects with any eye disease apart from slight refractive errors and 55 patients with varicocele. Retinal arteriolar and venular diameters were measured and summarised as central retinal arteriolar equivalent (CRAE) and central retinal venular equivalent (CRVE). Retinal microvascular diameters and the arteriolar–to‐venular ratio (AVR) were assessed with a digital retinal camera. All measurements and calculations were performed using a computer‐based program. The mean CRAE value was 151.8 ± 3.6 μm in the study group and 150.4 ± 4.5 μm in the control group. Mean CRVE value was 209.4 ± 5.9 μm in the study group and 200.1 ± 8.7 μm in the control group. AVR was found 0.72 ± 0.02 in the study group and 0.75 ± 0.03 in the control group. There were significant differences between groups in terms of CRVE and AVR. There were no significant differences between groups in terms of CRAE. The results of this study showed that the patients with varicocele showed significant changes on retinal vascular diameter.