Dataset Information

Multimodal registration of three-dimensional maxillodental cone beam CT and photogrammetry data over time.

ABSTRACT:

Objectives

In recent years, one of the foci of orthodontics has been on systems for the evaluation of treatment results and the tracking of tissue variations over time. This can be accomplished through analysing three-dimensional orthodontic images obtained before and after the treatments. Since complementary information is achieved by integrating multiple imaging modalities, cone beam CT (CBCT) and stereophotogrammetry technologies are used in this study to develop a method for tracking bone, teeth and facial soft-tissue variations over time.

Methods

We propose a two-phase procedure of multimodal (Phase 1) and multitemporal (Phase 2) registration which aligns images taken from the same patient by different imaging modalities and at different times. Extrinsic (for Phase 1) and intrinsic (for Phase 2) landmark-based registration methods are employed as an initiation for a robust iterative closest points algorithm. Since the mandible moves independently of the upper skull, the registration procedure is applied separately on the mandible and the upper skull.

Results

The results show that the signed error distributions of both mandible and skull registrations follow a mixture of two Gaussian distributions, corresponding to alignment errors (due to our method) and temporal change over time.

Conclusions

We suggest that the large values among the total registration errors correspond to the temporal change resulting from (1) the effect of treatment (i.e. the orthodontic changes of teeth positions); (2) the biological changes such as teeth growth over time, especially for teenagers; and (3) the segmentation procedure and CBCT precision change over time.

SUBMITTER: Bolandzadeh N

PROVIDER: S-EPMC3699013 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Multimodal registration of three-dimensional maxillodental cone beam CT and photogrammetry data over time.

Bolandzadeh N N Bischof W W Flores-Mir C C Boulanger P P

Dento maxillo facial radiology 20120727 2

<h4>Objectives</h4>In recent years, one of the foci of orthodontics has been on systems for the evaluation of treatment results and the tracking of tissue variations over time. This can be accomplished through analysing three-dimensional orthodontic images obtained before and after the treatments. Since complementary information is achieved by integrating multiple imaging modalities, cone beam CT (CBCT) and stereophotogrammetry technologies are used in this study to develop a method for tracking ...[more]

PMID: 22842636

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Dataset Information

Multimodal registration of three-dimensional maxillodental cone beam CT and photogrammetry data over time.

Objectives

Methods

Results

Conclusions

Publications

Multimodal registration of three-dimensional maxillodental cone beam CT and photogrammetry data over time.

Similar Datasets

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