Digital photography has become available to everybody. The aim of this study was to examine possibility of calculating the width of a missing central incisor ...
Coll. Antropol. 28 (2004) 2: 857–863 UDC 616.314-089.28:57.087.3 Original scientific paper
Use of Digital Photographs for Artificial Tooth Selection Asja ^elebi}1, Jasmina Stipeti}1, Petra Nola1, Nikola Petri~evi}1 and Milan Papi}2 1 2
School of Dental Medicine, University of Zagreb, Croatia Department of Practical Sciences, University of Split, Croatia
ABSTRACT Digital photography has become available to everybody. The aim of this study was to examine possibility of calculating the width of a missing central incisor using digital photographs. Digital photographs were obtained from 51 dentate subjects using a 3.1 Megapixel digital camera from various distances: 35 cm, 70 cm, 1 m and 1.5 m. For the calculation of the width of maxillary left central incisor (MLI), the following equation was used: MLIcalculated = Photographic width of MLI x IPD / photographic IPD. Statistical analysis was made (Kolmogorov-Smirnov test, dependent sample t-test, correlation and frequencies) using SPSS 10.0 for Windows. Results revealed no significant difference between the calculated MLI (70 cm, 1 m and 1.5 m distance) and actual MLI, however calculated MLI from 35 cm distance was significantly different from the actual MLI value (p0.05) and between
three different observers (one way ANOVA; p>0.05). Maximum difference between three observers in two time intervals was 0.8 mm for interpupillary distance, 0.2 mm for the width of MLI, 0.2 for the interpupilary distance on photographs and 0.1 mm for the width of MLI on photographs. These values were within acceptable limits clinically. Finally, one observer completed all the measurements. Statistical analysis was made using SPSS 10.0 for Windows (Chicago, Illinois). The normality of the distribution was tested by the one sample Kolmogorov-Smirnov test, descriptive statistics was also made, as well as t tests for dependent samples. Results The results for the calculated tooth width from 4 different photographs are shown in the Figure 3. The width of MLI calculated using the photograph (35 cm distance) showed bigger values than the actual width, which is a tendency to overestimate the actual width. The results of the dependent t test between calculated MLI width from each photograph (35 cm, 70 cm, 1 m and 1.5 m distance) and the actual width are shown in the Table 1. There was a statistically significant difference between the calcu859
A. ^elebi} et al.: Digital Photography and Artificial Teeth, Coll. Antropol. 28 (2004) 2: 857–863 10
x
9
SD
8 7
mm
6 5 4 3 2 1 0 Central left Calc ulated f rom Calculated from Calculated f rom Calculated f rom maxillary incisor image from 35 c m image from70 cm image f rom 1 m image from1,5 m x
8,347
8,761
SD
0,803
0,924
8,421 0,825
8,317
8,287
0,933
1,245
Fig. 3. Width of the actual left maxillary incisor (MLI) and calculated width of MLI from photographs made with a digital camera from 35 cm distance, 70 cm distance, 1 m distance and 1.5 m distance
lated MLI width and the actual MLI width for the photographs taken from a 35 cm distance (p0.05).
and the MLI width calculated from an image made from a 70 cm distance. Percentage of calculated maxillary left central incisor (MLI) values that fell within ±0.3 mm; ±0.5 mm and ±1 mm range of the actual MLI values are shown in the Table 3. If a clinician would be satisfied with a difference of calculated MLI that would provide a central incisor of ±0.3 mm of a patient’s natural tooth, then 33% of the results calculated from an image from 35 cm distance would be acceptable,
Paired intercorrelations are presented in the Table 2. All calculated MLI values were significantly correlated with actual MLI value and the highest correlation (0.914) was between actual MLI width
TABLE 1 t-TEST FOR DEPENDENT SAMPLES BETWEEN ACTUAL MAXILLARY CENTRAL INCISOR VALUE (MLI) AND CALCULATED MLI VALUES FROM IMAGES MADE WITH A DIGITAL CAMERA FROM 35 CM DISTANCE, 70 CM DISTANCE, 1 M DISTANCE AND 1.5 M DISTANCE
VARIABLE Measured Measured Measured Measured
MLI MLI MLI MLI
value value value value
: : : :
calculated calculated calculated calculated
MLI MLI MLI MLI
value value value value
– – – –
t = t-value; df = degree of freedom; p = p-value
860
35 mm 70 mm 1m 1.5 m
t
df
p
–3.813 –1.55 0.299 0.437
50 50 50 50
