Measurement of Incisor Overjet and Physiological Diastemata Parameters in Quarter Horse Foals.

The research article focuses on quantifying abnormalities in horse jaw length and positioning, specifically the incidence of overjet and physiological diastemata sizes among Quarter horse foals aged 4 to 7 months. The authors also introduce a field technique for taking such measurements effectively.

Objective of the Study

• The study aimed to determine the prevalence of incisor overjet- a condition where the upper front teeth (incisors) horizontally overlap the lower teeth, assess the dimensions of physiological diastemata- the natural spaces between the teeth, in young Quarter horses, and correlate these findings with factors like age, gender, and lineage.
• Another objective was to develop a simple field technique that can be used to monitor jaw growth in horses and measure incisor malocclusion and physiological diastemata lengths.

Analysis and Findings

• Overjet was found to be prevalent in 51% of the young horses studied, with female foals being overrepresented (61.5%).
• The study noted higher instances of overjet in foals from show and race lineages compared to other categories.
• Significant differences were observed in the lengths of the maxillary (upper jaw) and mandibular (lower jaw) physiological diastemata across all age groups studied.

Correlation with Age

• The findings showed an expected positive correlation between age and the size of physiological diastemata in both the upper and lower jaws.
• In terms of overjet presence, it was found in 44.4% of 4-month-old foals, and this percentage generally rose with age, reaching 60% in 7-month-old foals. However, the correlation between age and overjet was considered weak.

Conclusions

• The study concluded that incisor overjet is quite common among Quarter horse foals, particularly those from show and race lineages.
• The field technique introduced for physiological diastema measurements was deemed effective based on the results of the study.