Unit:
Faculty of MedicineLibrary of the School of Health Sciences
Dissertation committee:
Περρέα Δέσποινα , Ομότιμη Καθηγήτρια, Ιατρική Σχολή, ΕΚΠΑ
Βερύκοκος Χρήστος , Επίκουρος Καθηγητής, Ιατρική Σχολή, ΕΚΠΑ, Επιβλέπων
Μπιτσάνης Ηλίας, Επίκουρος Καθηγητής, Οδοντιατρική Σχολή, ΕΚΠΑ
Ψάρρας Βασίλειος, Επίκουρος Καθηγητής, Οδοντιατρική Σχολή, ΕΚΠΑ
Βάρδας Εμμανουήλ, Επίκουρος Καθηγητής, Οδοντιατρική Σχολή, ΕΚΠΑ
Φαρμάκης Ελευθέριος-Τέρρυ, Επίκουρος Καθηγητής, Οδοντιατρική Σχολή, ΕΚΠΑ
Κύκαλος Στυλιανός, Επίκουρος Καθηγητής, Ιατρική Σχολή, ΕΚΠΑ
Original Title:
Η επίδραση της μακροχρόνιας διαφοροποίησης της σύστασης της διατροφής στην αύξηση των γνάθων επιμύων
Translated title:
The long term effect of diet consistency on wistars' jaw growth.
Summary:
INTRODUCTION: Various published studies focused on the relationship between mastication and growth of the mandible because it is considered that mandibular growth is dependent on the loads exerted by the function of the masticatory muscles. Moreover it has been pointed out that the increase of orthodontic anomalies is due to the modern softer diet. Even in rats, soft diet is one of the factors causing malocclusions. All of the studies have been experimental, mainly in rodents, since this research is impossible to be applied on humans in a short period of time. Most experimental studies suggested that occlusal loading affects bone mass, bone amount, bone density, the length and the width of the bone, the degree of mineralization, the genetic expression. It is stated that bone volumes and thickness of the mandible of rats fed with soft diet were smaller when compared to animals fed with hard diet. The mandibles and condyles were smaller and less dense in the rats of soft diet as compared to controls. Furthermore the length and the width of the condyle in the soft diet group of animals were smaller as compared to the condyle of the hard diet group of animals.
AIM: The aim of this study is to evaluate if food concistency affects the jaw growth within one or even three generations.
METHODS: 60 female Wistar were the sample of this reasearch. They were radomly equaly seperated in two groups. In the first group the wistar had to eat only soft diet and in the second group their diet had hard concistency. Twenty four wistar age of 30 days were the primary sample. They were seperated in four groups. Each of the first two groups had 10 female (group 1, group 3) wistar and the other two growps had two male each (group 2, group 4). Group 1 and 2 were eating hard diet and group 3 and 4 were eating soft diet for 30 days. After that group 1 and 2 were mixed together in order to reproduct. Same procedure was followed for the other 2 groups. The reproduction procedure was followed again for the next 2 generations. The female wistar were seperated from their descendants after the ablactation period. At that point X-rays (Lateral cephalometric X-rays, Cone beam computed tomography) were taken and the animals were sacrifised. There were selected 14 craniofacial landmarks and 2 lines connecting two landmarks for the evaluation of linear measurements on the mandibular changes on the digital cephalometric X-rays and on the CBCT files. For their statistical analysis Beferroni test was used. The main craniofacial structures depicted on lateral cephalograms were digitized and traced with 12 curves and 90 landmarks, of which 74 were semilandmarks and 16 were fixed landmarks. These landmarks were subjected to Procrustes superimposition and Principal Component Analysis (PCA) in order to describe shape variability of the cranial base, maxilla and mandible, as well as of the whole craniofacial complex. For statistical analysis, a permutation test was used (10,000 permutations without replacement).
RESULTS: The food concistency affects the jaw growth and specificly the mandible. The wistar of soft diet had significant changes on the condyle (smaller), in the coronoid process (smaller) and on the body of the mandible. The soft diet group appears to have more bone changes withing the period of 3 generations as the condyle, the coronoid process and the angle of the mandible was changing. It apears that the most changes were in the vertical dimension. They were not significant changes found on the hard diet group. Finaly we can probably assume that they were some epigenetic changes since changes that happen in one generation were followed to the next.
Main subject category:
Health Sciences
Keywords:
Diet consistency, Jaw growth
Number of references:
107
