Table 2.
Definition on dental anomalies and characteristics
| Term | Definition |
|---|---|
| Deviations in the enamel formation | |
| Hypoplasia | Quantitative macroscopic defect of the enamel, reduced thickness of enamel. The borders of the defect should be rounded and smooth [9, 10]. The pits should be of significant size or appear more than once on the surface of the tooth. |
| Invagination | A clear outline of enamel inside the second maxillary incisors [16] (4.24)a. |
| Alteration of the root anatomy | |
| Short root | Short root is when the root appears distinctly shortened compared to mean root length [16] (4.29)a. |
| Blunting of root apex | Root ends with a clear blunting of apex [7]. |
| Obliteration of pulp canal | The pulp canal is not visible on radiographs, because of deposits occluding the root canal [16] (4.47)a. |
| Pulp calcification | Foci of calcification in the dental pulp. Radiographically visible opaque structures in the pulp chambers. They may occur as a single dense mass or as several small radioopacities [8]. Pulp calcification was assessed on molars only. |
| Root flexion | A minimum of a 45 degrees bend between the axis for the apical respective the coronal part of the root. |
| Disturbances in the eruption or tooth number | |
| Impaction | Absence of tooth eruption due to an obstacle in the eruption path or ectopic position of the tooth germ [11]. |
| Primary retention | Absence of tooth eruption without an obstacle in the eruption path or ectopic position of the tooth germ before gingival emergence [11]. |
| Secondary retention | Arrested eruption after gingival emergence [11]. |
| Hypodontia | Congenital absence of at least one permanent tooth or tooth germ, seen as persistence of primary teeth [15]. |
| Hyperdontia | Teeth present in addition to the normal tooth set, seen in the permanent dentition [14]. |
| Dental occlusion | |
| Sagittal molar occlusion | (if first molar is missing the canine and premolar relationship are the guide [15]) |
| Class I | The mesiobuccal cusp of the upper first molars occludes in the mesiobuccal fossa of lower first molar [12]. |
| Class II | The mesiobuccal cusp of the upper first molar occludes ≥ ½ width mesial to the mesiobuccal sulcus of lower first molar [12]. |
| Class III | The mesiobuccally cusp of the upper first molar occludes ≥ ½ premolar width distal to the mesiobuccal sulcus of lower first molar [12]. |
| Lateral cross bite | The buccal cusp of the maxillary tooth occludes lingually to the buccal cusp of the mandibular tooth; minimum two teeth in one side (M, P, C) [16] (4.62)a. |
| Open bite | Vertical distance between incisal edges of incisors perpendicular to occlusal plane > 0 [46] (4.61)a. |
| Overbite, increased | Maxillary anterior teeth cover the crown of the mandibular teeth totally [16] (4.63)a. |
| Crowding of teeth | Deficit of space in the dental arch visible by severely rotated teeth and/or buccally or lingually displaced teeth [16] (4.57)a |
| Midline diastema | Space between the upper central incisors > 1 mm. |
| Spaced teeth | Diastema in multiple places (≥4) in the lower or the upper dental arch [16] (4.58)a. |
| Ectopic position | Tooth totally displaced outside the normal position in the dental arch [13]. |
aFigures in parentheses are the respective paragraphs in La Dure-Molla 2019 [16]