Unit 4

• Mandibular: lower jaw or mandible
• Maxillary: upper jaw or maxilla
• Permanent or succedaneous dentition: Formed by 28 or 32 teeth, permanent
• Primary dentition: made up of central incisors, lateral incisors, canine (cuspid), first molar and second molar. Bottom jaw is made up of the same
• Formula for primary teeth is I 2/2, C 1/1, M 2/2 = 10
• Permanent dentition: Made up of central incisor, lateral incisor, canine, first premolar, second premolar, first molar, second molar and third molar. Same bottom and top jaw
• Permanent dentition formula: I 2/2, C 1/1, P 2/2, M 3/3 = 16
• Zsigmondy/Palmers system: i Deciduous dentition, Marked by letters from A to E starting from the central incisors. also uses the LA expression which determines which quadrant they are in
• Zsigmondy/Palmer's system: ii Permanent dentition, unlike deciduous it is identified by numbers from 1 to 8 starting with the central incisor. Also uses L1 method of expression
• Universal system: i Deciduous dentition, teeth are marked alphabetically from A to J on maxilla and K to T on mandibula.
• Universal system: ii Permanent dentition, numerically from 1 to 16 and 17 to 32.
• Viktor Haderup system: i Permanent dentition, upper teeth are + and lower are -, also marked by numbers 1 to 8 starting from central incisor
• Viktor Haderup system: ii Deciduous dentition, upper jaw marked by + and bottom jaw by -. Also marked with numbers 01 to 05 starting from central incisors
• FDI System: i Permanent dentition, each quadrant is assigned 1,2,3 or 4. From there the numbers progress like the universal system from the central incisors.
• FDI System ii. Deciduous dentition, similar to permanent dentition but this time quadrants are labelled as 5,6,7 and 8 and co labelled with 1 to 5 starting from the central incisor
• Incisor: made up of a crown and root. These meet at the cervical line or cementoenamel junction. End portion of root is called Apex. Crown has an incisal edge or ridge.
• Crowns of canines, premolars and molars have cusps. These are the cutting edge. When these converge that form fissures (F) and fossa.
• If a tooth has more than one root, it has multiple apices.
• Two roots: bifurcation (BI)
• 3 roots: trifurcation
• Hard tissue made up of enamel, cementum and dentin
• Soft tissue also called pulp is contained within the PCH, pulp chamber and PC, pulp canal. Other parts contain supplementary canal SC, Pulp horn PH, and apical foramen AF
• Gingiva is made up of the gingival crevice GC and gingival mergin GM
• Teeth held to alveolar bone B
• Periodontal ligament holds teeth within the bone
• Alveolar process: portion of jawbone that is responsible for supporting teeth
• Alveolus is the bone of the tooth socket
• Premolars and molars have 5 surfaces
• The surfaces of Premolars and molars are: Buccal (facial surfaces), lingual, occlusal, mesial and distal
• The surfaces of canine and incisors are: Labial, lingual, Incisal, mesial and distal
• All surfaces that face the cheek are called facial surfaces
• Incisors and canines are called anterior teeth as a group
• Cusp (MBC): Elevation or mound on the crown making up a divisional part of occlusal surface
• Tubercle (T): Smaller elevation on some portion of the crown produced by an extra formation of enamel. Seen on deciduous maxillary canine
• Cingulum (CI): Lingual lobe of an anterior tooth. Its mesiodistally convex
• Ridge: Lineal elevation on tooth surface. Named according to location
• Marginal ridge (BCR): Reounded borders of enamel that form the distal and mesial margins. In posterior this forms occlusal ridge and on anterior it forms lingual ridge
• Triangular ridge: descends from tip of cusps towards concave occlusal surfaces.
• Transverse ridge: Formed when two triangular ridges come together. Ridges that travel from buccal to lingual surfaces. Form V shape where it fits with the opposing posterior tooth
• Oblique ridge: Ridge that crosses molar surface obliquely. Formed with the joining of triangular ridges of DB and ML cusp.