Another family with the 'Habsburg jaw'

Embracing Personalized Medicine in Dentistry

Aim:

The aim of this systematic review was to evaluate the number of articles in the area of personalized medicine specific to dentistry.

Materials and Methods:

Electronic search using three databases was performed using PubMed, Embase, and Scopus search.

Results:

Results suggest that there is a definite need for more awareness and research pertaining to this specific area.

Conclusion:

With this background, the authors have written a comprehensive review on applications of personalized medicine in various branches of dentistry.

Major gene and multifactorial inheritance of mandibular prognathism

Mandibular prognathism typically shows familial aggregation. Various genetic models have been described and it is assumed to be a multifactorial and polygenic trait, with a threshold for expression. Our goal was to examine specific genetic models of the familial transmission of this trait. The study sample comprised of 2,562 individuals from 55 families. Complete family histories for each proband were ascertained and the affection status of relatives were confirmed by lateral cephalograms, photographs, and dental models. Pedigrees were drawn using PELICAN and complex segregation analysis was performed using POINTER. Parts of some pedigrees were excluded to create one founder pedigrees, so the total N was 2,050. Analysis showed more affected females than males (P = 0.030). The majority of the pedigrees suggest autosomal dominant inheritance. Incomplete penetrance was demonstrated by the ratio of affected/unaffected parents and siblings. The heritability of mandibular prognathism was estimated to be 0.316. We conclude that there is a major gene that influences the expression of mandibular prognathism with clear signs of Mendelian inheritance and a multifactorial component.

The postural basis of malocclusion: a philosophical overview

Over the last 100 years, many theories have attempted to explain the cause of malocclusion. Most have stated that it is inherited, but, more recently, greater emphasis has been placed on the influence of the environment, especially the activity and the posture of the oral soft tissues. Unfortunately, it is not possible to measure long-term posture with any precision, and this has reduced its perceived importance. When some evidence is missing and much of the rest conflicting, there is merit in moving from the traditional "prove-it" attitude to philosophical reasoning to separate the probable from the improbable. We do not know to what extent posture and parafunction might be inherited, but there can be no doubt that facial and dental structures are, at times, strongly influenced by the soft tissues and that some malocclusions appear to have a postural basis. This article undertakes a philosophical examination of the conflicting strands of evidence that link oral posture with malocclusion, hoping to create a theory based solely on the restricted evidence that is broadly accepted by all sides in this age-old debate.

On the genetics of mandibular prognathism: analysis of large European noble families

Mandibular prognathism is assumed to be a polygenic trait in the vast majority of cases. In a few families, this phenotype and perhaps a syndrome with a broader spectrum of facial anomalies seems to be determined by a single dominant gene of very low frequency (McKusick No *176700). The phenotype is known to have occurred independently in several European noble families. We constructed a pedigree comprising 13 of these families with 409 members in 23 generations in which mandibular prognathism has been segregating. Obviously, the presumed dominant gene is not fully penetrant in the heterozygous state. Pedigree analysis using the Elston-Stewart algorithm yields a maximum likelihood estimate (MLE) of p = 0.955 (SE 0.038) of the penetrance parameter.