Method of determining the position of the hyoid bone by lateral telerentgenogram

Abstract

The purpose of this study is to identify the difference in the position of the sublingual bone on the lateral telerentgenogram in patients with normal and infantile type of swallowing.
Materials and methods.
The analysis of lateral TRG of 300 patients aged 18 to 55 years who sought orthodontic care and underwent diagnostics was carried out. To determine the position of the hyoid bone, we proposed a new parameter — the NHS angle formed by the hyoid bone and the base of the skull. There were 3 groups of 100 TRG each: I — somatic type of swallowing, normal values of the type of growth, normognathia in size, position and inclination of the jaws (control group); II — somatic type of swallowing, with horizontal type of growth; III — infantile type of swallowing and vertical type of growth. The position of the hyoid bone relative to stable skeletal landmarks was evaluated, and the relationship between the position of the hyoid bone and the type of swallowing was revealed.
Results.
The value of the NHS angle in group I was 33° in group II — 35°, in III — 32°.
Conclusions.
The difference in the position of the hyoid bone in patients with infantile and somatic type of swallowing exists and averages 2—3°. The proposed NHS angle can be used in the analysis of patients’ lateral TRG and observation during the treatment of dental anomalies and deformities