Biomedical subjects

S Bhole

Publications and source records attributed to S Bhole.

5 recordsLinked to original sources

PubMed1997

Head positioning and projection errors in submentovertex radiographic analysis.

This study examined the changes seen on the submentovertex radiograph when the head is not extended sufficiently. A human dry skull supported on a cephalostat was used to simulate head extension. The range of rotation tested was an under-rotation of the skull of 30 degrees to an over-rotation of 10 degrees in intervals of 5 degrees. The measured variables were the intercondylar axis angles, corpus lengths and condylar widths. The relationships between skull rotation and changes in these variables were determined. Three selected landmarks, the spinosa points (right and left) and the pogonion point of each radiograph were located and compared spatially with the same points on the ideal radiograph. The results showed that variation in skull rotation affects both linear and angular measurements significantly (P < 0.01). Landmarks further away from the axis of rotation are affected by distortion more than those nearer to it.

Cephalometry↗

PubMed1996

A survey of reasons for extraction of permanent teeth in Singapore.

A survey was carried out to determine the reasons for tooth extractions of permanent teeth in Singapore. Data were obtained from 52 dentists practising general dentistry over a period of 12 months. At the end of the 12-month period, data were collected from 1276 patients, from whom a total 272 teeth were extracted. In this population group, the results showed that the percentage of teeth extracted due to periodontal reasons and caries were about the same, that is 35.8% and 35.4%, respectively. There was an increase in teeth extracted due to periodontal reasons with age. In patients above 40 yr, an average of 76% of teeth were lost due to periodontal reasons. An average of 26.7% of teeth were lost due to periodontal reasons in patients under 40 yr old. However, the trend for loss of teeth due to caries is reversed. Posterior teeth were more frequently extract compared to anterior teeth. Third molars accounted for 24.7% of all extractions carried out, whilst central incisors were 8.0% of all extractions. Molars were often lost due to caries and lower anterior teeth were most frequently lost due to periodontal reasons. The results of this study did not demonstrate one predominant reason for extraction. Both caries and periodontal reasons were equally common causes of tooth extraction.

Adolescent↗

PubMed1996

A cross-cultural comparison of perceived sources of stress in the dental school environment.

This study compared the perceived sources of stress in the dental school environment between an American and a South East Asian (Singapore) dental school across their entire curricula (D1-D4 years). The dental environmental stress (DES) questionnaire was administered to 137 (98 percent) Singapore dental students and results were compared to a previous study conducted at an American school. Significant differences were found for 12 questionnaire items across the four classes for the American cohort as compared to 13 in the Singapore cohort. While the greatest stressor for Singapore students was completing graduation requirements, American students were most stressed by examinations and grades. The overall perception of stress by Singapore students was higher than for their American counterparts. The primary concern for both cohorts was, however, related to the different areas of their academic courses.

Analysis of Variance↗

PubMed1995

Shade match of tooth-colored restorative materials based on a commercial shade guide.

Many restorative materials are claimed by their manufacturers to match the Vita shade guide. To verify this claim, 40 dental personnel were asked to color match five different restorative materials to their respective Vita shade tabs according to a 5-point scale (1 = very poor color match; 5 = excellent color match). Three shades were chosen for each restorative material (a mid-Value shade as well as the highest Value shade and the lowest Value shade present in each system). Pooled scores indicated that the resin composite materials had significantly better overall shade match than did the other materials evaluated and that one resin-modified glass-ionomer cement had significantly better shade match than did the "compomer" and another resin-modified glass-ionomer cement. Only 11% of the scores for all material and shade combinations were given a good or excellent rating (score greater than 3). Shade match to the Vita shade guide was not material dependent but tended to differ among the different Value shades evaluated.

Analysis of Variance↗

PubMedDate not supplied

Comparison of aesthetic properties of tooth-colored restorative materials.

The objective of this study was to compare the aesthetic properties of color and translucency of Vita shade-based tooth-colored restorative materials, including composite resins, a polyacid-modified composite resin, and resin-modified glass-ionomer cements via clinical discrimination by human evaluators. The hue/chroma, value, and translucency of the five different materials chosen to represent the range of commercially available tooth-colored restoratives were graded by 40 dental personnel against the body of their respective Vita shade tabs using a five-point scale (1 = very poor; 2 = poor; 3 = average; 4 = good; 5 = excellent). Results confirm the clinical observation that the hue/chroma, value, and translucency of the different materials evaluated do not match the Vita shade guide to which they are supposedly keyed. The aesthetic properties of hue/ chroma, value, and translucency for the material evaluated were all shade dependent. Comparison of pooled results revealed that none of the materials had good or excellent ratings and that the composite resins had significantly better hue/ chroma, value, and translucency match to the Vita shade guide than the other materials evaluated.

Color↗