Table 1 Nonmetric dental traits examined in this study
Maxillary | Definition | Teeth | Mandibular | Definition | Teeth |
|---|---|---|---|---|---|
Shoveling (Fig. 1) | Affected teeth have pronounced lingual marginal ridges and deeper lingual fossae than normal | 1, 2, 3 | Shoveling (Fig. 1) | Teeth with pronounced lingual marginal ridges and deeper lingual fossae than normal | 1, 2, 3 |
Talon cusp (Fig. 2) | An enamel projection on the cingulum area | 1, 2, 3 | Talon cusp (Fig. 2) | An enamel projection on the cingulum area | 1, 2, 3 |
Carabelli cusp (Fig. 3) | A non-functional cusp or tubercle on the mesiolingual surface with expression ranges from a slight groove or pit to a large cusp | 6, 7 | Protostylid (Fig. 4) | A triangular arrangement of cusps with the protostylid cusp located mesiobuccally | 6, 7 |
Fifth cusp (Fig. 5) | An extra enamel projection between the DB and DL cusps | 6, 7 | Hypoconulid absence (4-cusp) (Fig. 6) | Molars with 4 cusps without the distal cusp (hypoconulid) | 6, 7 |
Hypocone absence (3-cusp) (Fig. 7) | The 2nd molar without the distolingual cusp (hypocone) | 7 | Deflecting wrinkle (Fig. 8) | The metaconid cusp ridge on the mesiolingual occlusal surface running from the ML cusp toward the central groove and central pit | 6, 7 |
Canine mesial ridge (Fig. 9) | An oblique ridge between the lingual ridge and mesial marginal ridge | 3 | Distal trigonid crest (Fig. 10) | A transverse ridge that connects two mesial cusps | 6, 7 |
Canine distal accessory ridge (Fig. 9) | An oblique ridge between the lingual ridge and distal marginal ridge (DMR) | 3 | Tuberculum sextum (sixth cusp) (Fig. 10) | An extra enamel projection on the distal marginal ridge | 6, 7 |
Sixth cusp (tuberculum sextum) (Fig. 10) | An extra enamel projection on the distal marginal ridge | 6, 7 | Accessory cusp in the mesial marginal ridge (Fig. 11) | An extra enamel projection on the mesial marginal ridge (MMR) | 4, 5, 6, 7 |
Accessory cusp on the mesial marginal ridge (Fig. 11) | An extra enamel projection on the mesial marginal ridge | 4, 5, 6, 7 | Accessory cusp on the distal marginal ridge (Fig. 11) | An extra enamel projection on the distal marginal ridge | 4, 5, 6, 7 |
Accessory cusp on the distal marginal ridge (Fig. 11) | An extra enamel projection on the distal marginal ridge | 4, 5, 6, 7 | Mesial accessory ridge (Fig. 12) | The accessory ridge between the MMR and triangular (central) ridge | 4, 5 |
Mesial accessory ridge (Fig. 12) | The accessory ridge between the MMR and triangular (central) ridge | 4, 5 | Distal accessory ridge (Fig. 12) | The accessory ridge between the DMR and triangular (central) ridge | 4, 5 |
Distal accessory ridge (Fig. 12) | The accessory ridge between the DMR and triangular (central) ridge | 4, 5 | Accessory cusp on lingual (Fig. 13) | An extra enamel projection on the lingual | 4, 5, 7 |
Tuberculum intermedium (Fig. 10) | The accessory cusp between the lingual cusps (tuberculum intermedium) | 6, 7 |