Modern trends in modeling of extra-oral defects.

Maxillofacial prostheses are usually fabricated on the basis of conventional impressions and techniques. The extent to which the prosthesis reproduces normal facial morphology depends on the clinical judgment and skill of the individual fabricating the prosthesis. Recently, as a result of advances in technology, various computer-aided design and manufacturing techniques have been successfully introduced for the automated fabrication of maxillofacial prostheses. These systems are able to provide more consistently accurate reproduction of facial morphology.

A comparative study to evaluate the discrepancy in condylar guidance values between two commercially available arcon and non-arcon articulators: A clinical study.

Aim: The purpose of this study was comparative evaluation of sagittal condylar values of arcon and non-arcon articulators with cephalometric readings and to determine the amount of discrepancy in sagittal condylar guidance values between arcon and non-arcon articulators using same protrusive record. Materials and Methods: Twenty subjects in the age group of 19-35 years, free from temporomandibular joint dysfunction, and occlusal disharmony, with healthy dentition participated in the study. Hanau H2 (non-arcon type) and Hanau Wide-Vue (arcon type) articulators were programmed for sagittal condylar guidance values using the same protrusive record made in polysiloxane bite registration material with edge to edge degree of protrusion. The resultant values for both the articulators on either side were compared with values obtained from tracing of digital lateral cephalogram using Kodak Dental imaging Window software 6.6.3.0-C program. The tabulated data were subjected to statistical analysis, ANOVA (Fishers 'F' test) for group comparison, Tukey's HSD test for inter-comparison, student's unpaired 't' test for intra-group comparison, and level of significance (P) was calculated using the same. Results: The mean sagittal condylar guidance values of the three different groups were found to be very highly significant (P=0.001) and highly significant (P=0.002) on the right and left sides respectively. There was a very highly significant difference (P=0.001) and highly significant difference (P=0.003) between the arcon and non-arcon group on the right and left side respectively. No significant difference was found between the arcon and cephalometric group (P=0.284 right, P=0.853 left) and a statistically significant difference was found between the non-arcon and cephalometric group (P=0.049 right, P=0.015 left). On intragroup comparison there was no statistically significant difference in sagittal condylar values on the right and left sides. Conclusion: The mean difference in the sagittal condylar guidance values obtained from non-arcon and arcon articulators shows a low level of reproducibility, and no significant difference found in mean sagittal condylar values obtained from arcon articulator and cephalometric tracings indicates replication of sagittal condylar guidance value from image of articular eminence.

Prosthetic rehabilitation of large nasal septal defect with an intranasal stent: A clinical report.

Nasal septal perforation is a common complication of many nasal diseases such as congenital, infectious, trauma, and iatrogenic, and rarely may occur as a complication of systemic diseases, etc. The symptoms of uncorrected nasal septal perforations include crusting, epistaxis, difficulty in breathing, nasal twang in speech, postnasal discharge, foul-smelling, rhinorrhea, and hyposmia. Large nasal defects cannot be closed by hard acrylic resin nasal septal obturators because of the problems in access and path of insertion. However, obturation can be achieved by fabrication of a nasal stent that engages one of the nasal cavities. This clinical report describes prosthetic management of a patient with large nasal septal defect following septal surgery complication with an intranasal heat-processed acrylic resin stent. The stent is rendered patent for comfortable breathing, improves speech, is esthetically acceptable, dense and hygienic. These nasal stents indirectly separate the two nasal cavities with effective obturation of large nasal septal defects.

Efficacy of PS-VEPS in the detection of subclinical optic neuritis following ethambutol in therapeutic dosage

Ethambutol is an antimicrobial agent used frequently to treat tuberculosis. The most commonly recognized toxic effect of ethambutol is optic neuropathy, which may sometime result in irreversible vision loss. However, early recognition not only prevents this complication, it also increases compliance of the drug. This study was carried out to assess the usefulness of pattern-shift visual evoked potentials [PS-VEPs] in the detection of sub clinical optic neuropathy in patients on ethambutol for the treatment of tuberculosis in the recommended dosage. 30 consecutive patients of tuberculosis were studied before and after two months of ethambutol therapy. Ethambutol was administered in the WHO recommended dosage of 15mg/kg of body weight. All the patients underwent pattern shift visual evoked potential tests, which check the function of the visual pathway from the retina to the occipital cortex. PS-VEP abnormalities were seen in 5 patients [16.7%],out of which prolonged latency was documented in 3 patients [10%],increased latency difference was seen in 1 patient [3.3%] and abnormal amplitude difference was reported in 1 patient [3.3%].Associated psychophysical abnormalities of visual acuity in 2 patients [6.7%] and color vision abnormality in 1 patient [3.3%] were also seen. Our study confirms that during the treatment with ethambutol, PS-VEPs may reveal a surprisingly high percentage of sub clinical optic neuritis even at dosages considered to be safe. This needs attention in terms of patient care and drug compliance