Related Experiment Video
Updated: Jul 7, 2026
07:32
Measuring Maxillary Posterior Tooth Movement: A Model Assessment using Palatal and Dental Superimposition
Published on: February 23, 2024
Displaced premolars in panoramic radiography: fact or fallacy?
Nasila Nohadani1, Yango Pohl, Sabine Ruf
1Department of Orthodontics, University of Berne, Berne, Switzerland.
The Angle Orthodontist
|February 7, 2008
Summary
Panoramic radiographs (PRs) and lateral headfilms (LHs) show different premolar positions in nearly one-fifth of patients. This discrepancy in visualizing unerupted second premolar angulation is due to their buccolingual orientation.
Area of Science:
- Dentistry
- Radiology
- Orthodontics
Background:
- Accurate visualization of unerupted tooth position is crucial for orthodontic diagnosis and treatment planning.
- Panoramic radiographs (PRs) and lateral headfilms (LHs) are common imaging modalities, but their accuracy in depicting tooth angulation may vary.
Purpose of the Study:
- To evaluate the null hypothesis that there is no difference in premolar position between panoramic radiographs (PRs) and lateral headfilms (LHs).
- To assess the prevalence of discrepancies in the crown angulation of unerupted premolars as visualized on PRs versus LHs.
Main Methods:
- A dry skull was utilized with brass wire markers placed to simulate different sagittal and transverse angulations.
- Lateral headfilms (LHs) and panoramic radiographs (PRs) were taken of the skull with the markers in place.
- The direction of crown angulation of unerupted second premolars was compared between the two imaging techniques.
Main Results:
- A difference in the direction of crown angulation of unerupted second premolars between PR and LH was observed in 19.5% of cases.
- The primary reason identified for these angulation differences is the buccolingual orientation of the tooth.
- This buccolingual orientation can be misinterpreted as a mesiodistal angulation on the panoramic radiograph.
Conclusions:
- The null hypothesis was rejected, indicating a significant difference in premolar projection between PRs and LHs.
- Approximately one-fifth of patients exhibit differing premolar projections when comparing panoramic radiographs and lateral headfilms.
- Understanding these imaging discrepancies is essential for accurate orthodontic assessment and treatment planning.
Related Concept Videos
01:15Teeth
The formation of teeth, also known as odontogenesis, is a complex process that begins in utero, around the sixth week of embryonic development. There are three stages to this process: the bud stage, the cap stage, and the bell stage.
In the bud stage, the tooth germ (an aggregation of cells) starts to form in the developing jawbone. During the cap stage, the tooth germ differentiates into enamel organ, dental papilla, and dental sac, which will later develop into the tooth's enamel, dentin and...
In the bud stage, the tooth germ (an aggregation of cells) starts to form in the developing jawbone. During the cap stage, the tooth germ differentiates into enamel organ, dental papilla, and dental sac, which will later develop into the tooth's enamel, dentin and...
01:21Tooth Anatomy
The human tooth enables us to eat a variety of foods, speak clearly, and even aid in shaping our faces. Teeth are composed of various elements that work together. Here's a detailed look at the anatomy of a human tooth.
The Crown, Neck, and Root
The visible part of the tooth is referred to as the crown. It's covered by enamel, the hardest substance in the human body. The crown is uniquely shaped for each type of tooth, allowing for different functions such as cutting, tearing, or grinding food.
The Crown, Neck, and Root
The visible part of the tooth is referred to as the crown. It's covered by enamel, the hardest substance in the human body. The crown is uniquely shaped for each type of tooth, allowing for different functions such as cutting, tearing, or grinding food.