Dento-facial anomalies have been diagnosed for centuries. The
diagnosis or observation thereof is reported to date back to the Fifth
Century AD where Hippocrates observed and noted numerous
craniofacial deformities (Moyers, 1988)
Through a complex process of reception, selection and categorizationthe
human form particularly the cranium, jaws and related soft tissue
structures, have been studied and categorized over the years (Moyers,
1988). Dockrell (1952) focused on the aetiology of malocclusion and
through extensive work on the topic, established an equation for the
improved identification of aetiology of malocclusion. This equation
essentially communicates that a causative factor will act at a specified
time, on an identified tissue, to produce particular results. Thus
resulting in a deviation from the accepted “normal” relationship. This
will result in the development of an archetypally defined, classifiable
malocclusion. These so termed causative factors as elicited to in the
equation play a pivotal role in the outcomes or resultant malocclusions
(Dockrell, 1952). The plasticity in aetiology and resultant Skeletal or dental positional
discrepancy should not be overlooked. Multiple factors may act together
stabilising each other thus lessening the severity of the expected effect.
This research project aims to identify the potential of occlusal bite forces
as a causative factor in the “orthodontic equation” and shed light on
timing as well as resulting Skeletal and growth effects of variance in
occlusal force. Occlusal force is a combined and quantifiable
measurement of contributory muscle strength.
Through this study a comparative analysis of the occlusal force will be
carried out amongst subjects exhibiting differences in age, gender, race,
and growth pattern. This study aims to elucidate the influence of
occlusal forces and masticatory muscle strength in relation to the
resulting craniofacial development.
Data was collected from patients exhibiting various dental classes
namely Class I, Class II and Class III dental and Skeletal patterns. Bite
force strength of patients in primary, mixed and permanent dentition
was measured using an occlusal force meter. The occlusal force meter
was sourced from a Japanese based company, Nagano Keiki Co. LTD.
The readings were done in Kilo newton, which is the standard
international (SI) measurement of force.
The study population consisted of 180 male and 180 female subjects. This group was split into Skeletal Class I, II and III subjects and then
further divided into the three directions of growth (Horizontal, normal
The relationship of bite force to Skeletal Class and growth direction was
analysed using mean readings from five points of reference on each
subject. Analysis of covariance was carried out on the data set with a
mean age of 15,33 years (covariant). There was a significant difference
found in the bite forces between growth direction and Skeletal Class
P<0,05. There was also and interaction found between Skeletal classes
and direction of growth. These findings are supportive to the hypothesis
that a relationship exists between bite force and malocclusion.
Dissertation (MSc (Odont))--University of Pretoria, 2014.