ABSTRACT
The purpose of this study was to evaluate and compare the effect of varying layers of two commercially available die spacers on pre-cementation space of full coverage restorations in vitro and in vivo. Seven dies were prepared for each of 15 subjects. On three dies 1, 2, 3 layers of Pico-fit and on other three dies 1, 2, 3 layers of Yeti die spacers applied, wax pattern fabricated, invested and cast. Metal copings seated in vitro on die without die spacer and on prepared tooth of respective subject with fit-checker. Thickness of fit checker was measured using micrometer at mid-axial, mid-occlusal and near finish line locations that provided pre-cementation space. Result of ANOVA tests suggested significant difference among groups with varying layers. There was no significant difference between pre-cementation space achieved with Pico-fit and Yeti die spacers. The r values suggested positive correlation between the respective pair of in vivo and in vitro groups. (1) There was significant difference between pre-cementation space at mid-axial and mid-occlusal sites achieved with 1, 2 and 3 layers of die spacers except between 1 and 2 layers and 1 and 3 layers at mid-occlusal site. (2) Pre-cementation space achieved with Pico-fit and Yeti die spacers did not differ significantly for same location, layers and in vitro and in vivo. (3) Pre-cementation space achieved in vitro was analogous to pre-cementation space achieved in vivo for respective location, layers and die spacer.
ABSTRACT
BACKGROUND: As visual shade matching is subject to light source variables, this study was conducted to compare shade matching performance of dental students under two lighting conditions, ie, natural daylight and a commercially available daylight lamp. MATERIALS AND METHODS: Two sets of porcelain discs were prepared. The first set consisted of eight porcelain discs of shades A2, A3, A3.5, B2, B3, C2, C3, and D3 of the Vitapan Classical Shade Guide system. The second set consisted of three porcelain discs of shade A2, B2, and C2, having exactly similar L*a*b* values to those of the corresponding shade discs in the first set. Forty dental students were asked to find the closest match for the shades A2, B2, and C2 in the second set from the first set under natural daylight and daylight lamp conditions. The average ΔE between the presented and selected shade was calculated for each participant under the two lighting conditions. The significance was statistically assessed using a paired t test. RESULTS: The average ΔE between presented and selected shade for individual participants under natural daylight ranged from 0 to 4.84, with a mean of 2.24, while those under daylight lamp conditions ranged from 0 to 3.68, with a mean of 1.14. The difference was statistically significant, with P < 0.0001. CONCLUSION: Daylight lamp conditions significantly improved the shade matching performance of dental students.
Subject(s)
Dental Porcelain/radiation effects , Lighting , Prosthesis Coloring , Sunlight , Colorimetry , Dental Prosthesis Design , HumansABSTRACT
This clinical case report describes the oral rehabilitation of an adult female patient diagnosed with hypoplastic amelogenesis imperfecta with inadequate, deteriorated restorations of anterior teeth, inadequate clinical crown heights of posterior teeth due to severe attrition of hypoplastic enamel. Treatment included extraction of teeth with poor prognosis, root canal treatment and crown lengthening of severely worn out teeth & full coverage porcelain-fused-to metal fixed restoration of entire dentition. The main objectives of the selected treatment were to enhance the esthetics, restore masticatory function and eliminate the teeth sensitivity. These treatment objectives were successfully met by sequential fixed prosthodontics treatment using Pankey-Mann-Schuyler philosophy of complete occlusal rehabilitation. Treatment not only restored function and esthetic, but also showed a positive psychological impact and thereby improved perceived quality of life.
