The purpose of the course is to introduce students to the anatomy and function of the oral cavity. The focus is on tooth development, biology and morphology. Students are familiarised with the differences in the deciduous and permanent dentition, as well as with changes in the microstructure and macrostructure of teeth. Genetic influence on tooth development, acquired and hereditary changes in dental tissues and teeth. Besides the dentition of modern humans, students will also be familiarised with and compare the dentition of primates, herbivores and carnivores.
Introductory notes on the course; human dentition; monophyodont, diphyodont and polyphyodont dentition; tooth - subject of research; palaeontology - taxonomy, physical anthropology, evolution, phylogenetic reconstruction, human genetics; embryology - growth and development - teratology; significance of tooth morphology, clinical dentistry
- Dental notation – Zsigmondy notation system (Zsigmondy cross), Haderup system (+/-), two-digit system, notation using the first letter of Latin-derived names; odontometrics – meaning of the term; anatomical planes – sagittal, frontal and transverse, in which dental specialties they are used and why; permanent incisors – number, size, morphology, first and second upper permanent incisors, first and second lower permanent incisors, crown, root, surface of the tooth; general characteristics of incisors – dimensions
- Permanent canines – upper canines – time of eruption; dimensions; morphology; surface of the tooth; pulp cavity; importance for dental prosthetics; variations in the size of canines; hypodontia of canines
- Human premolars; variations in incisors and canines – upper and lower premolars; differences in the shape of occlusal surfaces and morphology of the crown; number of roots and root canals; variations in the morphology of incisors and canines; accessory cusps; pronounced cusps; supernumerary roots;
- Human permanent molars – general characteristics; number; dimensions; differences in the shapes of the occlusal surface of the upper and lower molars; differences in the number of roots and root canals; pulp cavity images
- Variations in premolars and molars – dimensions; accessory cusps; abnormalities and variations in the shape of the crown, root, pulp chamber, root canals; enamel pearls, cusp of Carabelli
- Gonadal dysgenesis – influence of extra or missing sex chromosomes on the growth and development of dental and osseous structures of the craniofacial region and oral cavity organs.
- Human deciduous teeth – general characteristics; differences and similarities with permanent teeth; number; colour; dimensions, diastemata; morphological characteristics of the crowns and roots of deciduous teeth; chronology of eruption; shape of dental arches of deciduous teeth
- Early stage of human tooth development – tooth development stages; bud stage, cap stage, bell stage; formation of the dental papilla; dentinogenesis; amelogenesis; crown and root development; Hertwig sheath; tooth eruption stages; inner enamel epithelium; outer enamel epithelium; stellate reticulum; odontoblasts; ameloblasts
- Root development, periodontal ligament; Hertwig sheath; epithelial diaphragm; single-rooted tooth development; multi-rooted tooth development; periodontium formation; periodontal ligament formation; alveolar process formation; tooth eruption; tooth eruption stages; chronology of eruption
- Development of occlusion – what is occlusion; types of occlusion; axial position of teeth and roots; relations in the intercuspal position; occlusal surface of teeth; occlusion of the upper and lower dental arch; radiographic images
- Human masticatory system – functional anatomy of the orofacial system; mastication; structures involved in mastication; articulation of the temporomandibular joint; muscles involved in mastication; occlusion of molars
- Dental arch; lip-cheek-tongue system – position of teeth in the upper dental arch; position of teeth in the lower dental arch; curvature of the upper and lower dental arch; various palatal heights; role of tongue in mastication
- Dental articulation, mechanism and characteristics – what is dental articulation; intercuspal position; protrusive movement; retrusive movement; occlusion; ideal occlusion; mandibular movements – symmetrical and asymmetrical; movements of the condyle; external and internal aspect of premolar and molar cusps; guiding cusps; supporting cusps
- Self-protective features of human dentition; interdental spaces; occlusion; dental arch curvature; tooth morphology and its influence; variations in lingual inclination; cementodentinal junction in the upper and lower dental arch; continuity of the upper and lower dental arch; effect of saliva and ferments; effects of vertical, axial and horizontal forces; cheeks and mucosa – protection from mechanical trauma; protection of the periodontium; variations in the shape of teeth affecting the development of periodontal disease
- Microscopic structure of dental hard tissue – including enamel, cementum and dentine; enamel – the hardest tissue in the human body, covers the surface of the crown, consists of enamel prisms, ameloblasts; dentine – the thickest layer of the tooth, covers the enamel, consists of dentinal tubules, high percentage of inorganic compounds; cementum – covers the tooth root, dentinoenamel junction, cementoenamel junction
- Enamel – chemical composition of the enamel; histological structure of the enamel; striae of Retzius, incremental lines; aprismatic enamel; enamel prisms – appearance, shape, size; unmineralised portions of the enamel – lamellae, tufts, spindles, Hunter-Schreger bands; thickness of the enamel on cusps, in the dental neck area; hydroxyapatite crystals, dimensions
- Dentine – chemical composition; histological structure of dentine; dentinal tubules; hydroxyapatite crystals; Tomes' processes; primary dentine; mantle dentine; secondary dentine; reparative secondary dentine; dead tracts, sclerotic dentin; tubular; intertubular; peritubular; atubular; predentine; Tomes' granular layer; permeability; cementodentinal junction
- Dental pulp – pulp anatomy, coronal pulp; radicular pulp; apical foramen; accessory canals; histological structure of the pulp; odontoblasts; fibroblasts; other cells in the pulp; ground substance of the pulp; vascularisation and innervation of the pulp; nutrition of the pulp-dentine complex; function of the pulp; regressive changes; fibrotic changes; denticles; diffuse calcification
- Cementum – the role of cementum on the surface of the root; part of the periodontium; physical and chemical properties; cellular and acellular cementum; age-related differences; cementicles; cementum repair; cementum cells; fibres; cementum resorption
- Anatomy of the periodontium – periodontal ligament, collagen fibres of the periodontal ligament – Sharpey's fibres, periodontal ligament cells
- Physiology of the periodontium – periodontal ligament cells, fibroblasts, cementoblasts, osteoblasts, osteoclasts and cementoclasts, epithelial cells, blood vessels and nerves, lymphatic system.
- Alveolar bone – classification, compact bone and spongy bone; morphology; chemical properties of the alveolar bone; organic matrix; non‐collagenous proteins; bone histology – osteoid; structural characteristics of the bone; Haversian canals; bone cells; (bone resorption); Sharpey's fibres; changes in bone structure
- Oral mucosa – the role of oral mucosa; epithelial layers – basal layer, spinous layer, granular layer, stratum corneum; cytokeratins; non-keratinocyte cells; melanocytes; Langerhans cells; Merkel cells; lamina propria; vermilion border; labial mucosa; alveolar mucosa; free and attached gingiva; dentogingival fibres
- Physiology of the oral cavity
- Vertebrate dentition – dentition of fish, amphibians and reptiles; characteristics of teeth during phylogenesis – changes in the number of teeth, specialisation and number of tooth replacements throughout life; horny teeth; forms of tooth implantation – acrodont, thecodont and pleurodont dentition; aprismatic and prismatic enamel; differences in the structure of dentine; examples of polyphyodont dentitions; chameleon – an example of monophyodont dentition; teeth of non-venomous snakes, snake teeth for injecting poison – a dentine canal or groove at the back side of the fang; turtles.
- Dentition of mammals – differences in the teeth of carnivores and herbivores - Toothless mammals – an example of baleen whales and anteaters; Baleen whales – number of teeth, homodont and polyphyodont dentition; Characteristics of the teeth of mammals – heterodont dentition, reduced number of teeth, highly specialised teeth, diastema; Characteristics of molars – secodont, selenodont, lophodont molars; Characteristics of the teeth of marsupials – carnivores and herbivores; Characteristics of the teeth of insectivores, cusps for piercing chitin shells of bugs
- Characteristics of ever-growing teeth - Definition and characteristics of ever-growing teeth, ever-growing incisors, canines and molars; Characteristics of the histological structure – enamel, dentine and predentine, deposition of secondary and tertiary dentine, dental pulp; Effect of tooth wear on tooth function; Characteristics of tooth eruption in the upper and lower jaw – consequences of fractures, characteristics of eruption in case of absence of the antagonist tooth; Congenital disorders related to ever-growing teeth.
- Evolution and formation of new species
- Dentition of monkeys; dentition of hominids
Topics of preclinical exercises:
1. Introductory notes on the subject matter of the course, terminology related to tooth morphology and dental anthropology, basic information about human dentition, anatomical reference points; topographic and anatomic signs on teeth – signs for identifying teeth; lingual inclination of lateral teeth; types of dental notation; based on a plaster model, students model the crown in a 1:3 ratio – first upper permanent incisor and upper permanent canine – using modelling clay
2. Modelling the crown and root of the first upper premolar using modelling clay, based on a plaster model and carving the second upper premolar in plaster; introductory notes about teeth; practicing various types of dental notation
3. General characteristics of molars (trigon and talon); lateral teeth are the most distal teeth; large occlusal surface area; teeth with supernumerary cups and laminae divided by fissures and grooves; they have an important role in crushing solid food; a total of 12 molars; lower molars – two roots; upper molars – three roots; modelling the first upper permanent molar using modelling clay; common variations in upper premolars; carving the upper lateral incisor in plaster
4. Carving the second upper molar in plaster based on a plaster model, in a 1:2 ratio – crown and roots; common variations in upper permanent molars; cusp of Carabelli – 0-7-grade classification, accessory cusps; reduced number of cusps; supernumerary roots and root canals; modelling the lower permanent central incisor in a 1:3 ratio using modelling clay, based on a plaster model
5. Modelling the second lower molar in a 1:3 ratio based on a plaster model; variability of lower permanent molars; enamel pearls; accessory cusps; root fusion and carving the lower permanent canine in plaster; variability of lower permanent front teeth
6. Modelling the first lower premolar in a 1:3 ratio based on a plaster model and carving the second lower premolar in plaster; lingual inclination of lower lateral teeth; variability of lower premolars
7. Modelling the lower permanent lateral incisor in a 1:3 ratio based on a plaster model and carving the first lower permanent molar; basic forms of lower molar occlusal surface drawings (Y and X)
8. Introductory notes about deciduous dentition in relation to permanent dentition – differences in colour, dimensions, physiological diastemata; eruption chronology; morphological differences; carving the upper deciduous central incisor in plaster and modelling the first upper deciduous molar in a 1:2 ratio using modelling clay, based on a plaster model
9. Modelling the upper deciduous lateral incisor in a 1:2 ratio using modelling clay, based on a plaster model and carving the second upper deciduous molar in plaster
10. Modelling the upper deciduous canine in a 1:2 ratio using modelling clay, based on a plaster model and carving the lower deciduous canine in plaster
11. Modelling the lower deciduous central incisor in a 1:2 ratio using modelling clay, based on a plaster model and carving the first lower deciduous molar in plaster
12. Modelling the lower deciduous lateral incisor in a 1:2 ratio using modelling clay, based on a plaster model and carving the second lower deciduous molar in plaster
13. Drawing morphological characteristics of coronal and root parts of the permanent lower teeth in various sectional views in a 1:2 ratio, using graph paper, based on an existing drawing; labial surface; palatal surface; drawing histological details of coronal and root parts of the permanent lower teeth – enamel, dentine, pulp chamber, cementum.
15. Test of modelling/carving two permanent teeth without a template
Assigned reading:
- Vodanović M., Brkić H., Dumančić J. Pavić Savičin I. Biologija i morfologija ljudskih zuba. Jastrebarsko: Naklada Slap. 2016.
- BerkovitzB. K.B., Holland G. R., Moxham B.J., Oral Anatomy, Histology and Embriology,3 Ed., Mosby, Edinburgh,2002.