Photogrammetric Correlation of Face with Frontal Radiographs and Direct Measurements

Concordance of the facial biotype between Bjork-Jarabak cephalometrics and photographic analysis of the facial opening angle

Background

Analysis of the facial biotype can provide useful information for orthodontic diagnosis and can determine the type of growth of a patient to guide orthodontic treatment. The objective of this study was to determine the concordance of the facial biotype according to Bjork-Jarabak cephalometric analysis and photographic analysis of the angle of facial opening in Peruvian individuals.

Material and Methods

This retrospective study included 244 cephalometric radiographs and frontal photographs of the same patients obtained from a database. The facial biotype (mesofacial, brachyfacial, or dolichofacial) was determined with the Björk-Jarabak polygon (cephalometric) and the angle of facial opening (photographic). Two trained investigators performed all the measurements. The concordance of the facial diagnosis was determined using correlations of the interclass coefficient and the kappa test. p<0.05.

Results

In cases with a mesofacial biotype, both analyses coincided in 60 individuals (68.2%), while in those diagnosed with a dolichofacial biotype, the analyses only coincided in 17 individuals (10.4%). There was no concordance between the two methods regarding the brachyfacial biotype since according to the angle of facial opening none of the individuals presented a brachyfacial biotype (kappa weighted test= 0.020, p=0.586).

Conclusions

Cephalometric and photographic analyses should be complementary and one should not substitute the other. Attention should be focused on dolichofacial and brachyfacial biotypes, which showed less concordance between evaluations. So, more studies are needed to follow this line of research. Key words:Facial biotype, cephalometry, photography, facial type, radiography.

Reliability of Photogrammetric Landmarks to the Conventional Cephalogram for Analyzing Soft-Tissue Landmarks in Orthodontics

Background

Graber introduced facial photographs as an internal diagnostic aid. Facial photographs could serve as an important alternative assessment tool in the absence of equipment for cephalometric analysis.

Objectives

The present study was aimed at assessing whether analyzing the photographs could have precision for assessing the landmarks appropriate for facial analysis. In addition, the relationship between frontal cephalogram and measurements on photographs was assessed.

Materials and Methods

Twenty individuals including both males and females within the age range of 18 years to 28 years were enrolled in the study. Frontal facial photographs, as well as frontal cephalograms, were obtained for all the included study participants. Various soft-tissue vertical and horizontal landmarks were marked on both radiographs and photographs. The data were collected and subjected to statistical analysis.

Results

The results showed a statistically insignificant difference between all the vertical and horizontal parameters on photographs and cephalograms. The reliability of the digital photographs was comparable to that of the cephalograms with nonsignificant differences in the recorded mean values using the one-way ANOVA test where the statistical significance level was kept at P ≤ 0.05.

Conclusion

The present study concluded that photography is a cost-effective and reliable method for soft-tissue landmark identification, and allows recording the images of sufficient quantity for analysis. Low-cost and easily captured photographic images can replace costly radiographic procedures without causing any discomfort to the patients.