Table 1.
Summary of included studies in the systematic review.
| Authors/ year/ country | Participants | Age (years) | Sample size | Sex | Method of zygosity determination | Record evaluated | Method of estimating genetic influence | Heritability coefficients for different parameters (where reported)/main outcomes |
|---|---|---|---|---|---|---|---|---|
| Corruccini et al. [18]/ 1980/USA | MZ and DZ twins | 12 to 17 | 32MZ +28 DZ (60 pairs) (total = 120) | NR | Serologic and dermatoglyphic criteria | Dental casts | Heritability coefficient* | Maxillary intermolar width: 0.16 Mandibular intermolar width: 0.22 Maxillary arch length: 0.42 Mandibular arch length: 0.28 Overjet: 0.4 Overbite: 0 Crossbite: 0.89 Buccal segment relationship: 0 Rotation and displacement: 0.27 |
| Potter et al. [19]/1981/USA | MZ and DZ twins | 12–17 | 87 MZ + 77 DZ (164 pairs; total = 328) |
162 F, 166 M | Serological | Dental casts | Heritability coefficient* | Overjet: −0.11 Overbite: 0.27 Crossbite: 0.44 Buccal segment relationship: 0.05 Rotation and displacement: −0.19 |
| Varma [33]/ 1986/ India | MZ and DZ twins | NR | 8 MZ + 8 DZ (16 pairs; total = 32) | NR | NR | Dental casts | t-test | Strong genetic influence on the palatal height (no significant difference between the means of palatal height among MZ twins but significant difference among DZ twins) |
| Sharma et al [20]/ 1986/ India | MZ and DZ twins | 17.5 (11–27) |
23MZ + 35 DZ (58 pairs; total = 116) | 61 F, 55 M | Serological | Dental casts | Heritability coefficient* | Maxillary intermolar width: 0.63 Mandibular intermolar width: 0.67 Maxillary arch length: 0.72 Mandibular arch length: 0.66 Palatal depth: 0.47 Overjet: 0.24 Overbite: 0.77 Crossbite: 0.27 Buccal segment relationship: 0.45 Rotation and displacement: 0.09 |
| Boraas et al. [34]/1988/USA | MZ and DZ twins and triplets (reared apart) | At reunion: MZ: 39.9, DZ: 42.1 |
44 twins + 3 triplets (total =97) | 64 F, 33 M | Serological | Dental casts | Heritability coefficient* | Maxillary intermolar width: −0.14 Maxillary intercanine width: −0.22 Overjet: −0.5 Overbite: 0.36 |
| Townsend et al. [35] 1988/Australia | MZ and DZ twins | 16.2 (13–26) |
48 MZ + 34 DZ (82 pairs; total = 164) | 80 F, 84 M | Serological | Dental casts | Heritability coefficient* | Overjet: 0.36 Overbite: 0.34 Buccal segment relationship: 0.24 Rotation and displacement: 0.26 |
| Richards et al. [36]/ 1990/Australia | MZ and DZ twins | 15.8 ± 3.3 | 29 MZ + 19 DZ (48 pairs) + control 45 (total = 141) | 70 F, 71 M | NR | Dental casts | Polynomial analysis | Genetic factors contributed to variation in maxillary arch shape and to a lesser extent to variation in mandibular arch shape but not to arch asymmetry |
| Lapter et al. [37]/1991/Croatia | MZ and DZ twins | 5.8–18.8 | 36 MZ + 60 DZ (96 pairs; total = 192) | NR | Test of similarity and blood tests if necessary | Dental casts | Heritability coefficient* | Maxillary intermolar width: 0.58 maxillary intercanine width: 0.69 Mandibular intermolar width: 0.11 Mandibular intercanine width: 0.31 Maxillary arch length: 0.73 Palatal depth: 0.11 Overjet: 0.76 Overbite: 0.46 |
| Harris et al. [38]/ 1991/USA # | Siblings | Assessed at ages 4, 14 and 20 | 30 sibling pairs (total = 60) | 28 F, 32 M | NA | Dental casts | Heritability coefficient | Reported higher heritability estimates at age 4 which decreased with age. Heritability estimates at age 20 Maxillary intercanine width: 0.05 Mandibular intercanine width: −0.2 Maxillary arch length: −0.01 Mandibular arch length: −0.25 Overjet: 0.43 Overbite: 0.19 Crossbite: −0.05 Buccal segment relationship: 0.24 Rotation and displacement: 0 |
| King et al. [15]/ 1993/USA | Siblings | 13.5 (9–22) |
104 sibling pairs (total =208) |
127 F, 81 M | NA | Dental casts | Heritability coefficient | Maxillary intermolar width: 0.32 maxillary intercanine width: 0.53 Mandibular intermolar width: 0.77 Mandibular intercanine width: 0.79 Maxillary arch length: 0.73 Mandibular arch length: 0.6 Overjet: 0.58 Overbite: 0.62 Crossbite: 0.45 Buccal segment relationship: 0.48 Rotation and displacement: 0.49 |
| Kasai et al. [39]/1995/Australia | MZ and DZ twins | NR | 37 MZ + 19 DZ (56 pairs; total = 112) |
112 M | NR | Dental casts | Fourier analysis | Genetic factors contribute mainly to the variation in arch size and to arch depth/arch breadth ratio than to other aspects of the dental arch. |
| Liu et al. [40]/ 1998/China | MZ and DZ twins | 6–12 | 56 MZ + 26 DZ (82 pairs; total =164) | 164 F | DNA fingerprinting | Dental casts | Heritability coefficient | Arch size demonstrated a strong heritability (0.72), but weaker heritability was associated with overjet, overbite, and buccal segment relationship |
| Cassidy et al.[41]/ 1998/USA | Siblings and triplets | 13.5 ± 1.69 | 145 sibling pairs and 10 triplets (total = 320) | NR | NA | Dental casts | Heritability coefficient | Maxillary intermolar width: 0.67 Maxillary intercanine width: 0.56 Mandibular intermolar width: 0.61 Mandibular intercanine width:0.48 Overjet: 0.23 Buccal segment relationship: 0.56 |
| Hughes et al.[16]/ 2001/Australia | MZ twins, same sexed and opposite sexed DZ twins and singletons | 3–7 | 70 MZ + 68 DZ + 11 OSDZ (149 pairs) + 114 singletons (total = 412) |
203 F, 209 M | DNA from buccal cells | Dental casts | Heritability coefficient and structural equation modelling | Interdental spacing: 0.62 to 0.81 Maxillary intermolar width: 0.87 Maxillary intercanine width: 0.84 Maxillary arch length: 0.79 Mandibular intermolar width: 0.89 Mandibular intercanine width: 0.69 Mandibular arch length: 0.87 Overbite: 0.53 Overjet: 0.28 |
| Eguchi et al.[2]/ 2004/Australia | MZ and DZ twins | MZ: 15.8 ± 3.5 DZ: 17 ± 4.7 |
44 MZ + 34 DZ (78 pairs; total = 156) | 73 F, 83 M | DNA from buccal cells | Digital dental casts | Heritability coefficient and Structural equation modelling | Maxillary intermolar width: 0.82 Maxillary intercanine width: 0.86 Mandibular intermolar width: 0.79 Mandibular intercanine width: 0.83 Maxillary arch length: 0.92 Mandibular arch length: 0.86 Palatal depth: 0.8 |
| Kawala et al.[42]/2007/Poland | MZ and DZ twins | NR | 90 MZ + 74 DZ (164 pairs; total = 328) | 136 F, 192 M | Serologic, morphologic criteria, and dermatoglyphics | NR | Heritability coefficient | The heritability coefficients had low or negative values. Only in males the values exceeded 0.1; (class II malocclusion: 0.11, mandibular crowding: 0.12) |
| Svalkauskiene et al.[43]/ 2015/Lithuania | MZ and DZ twins | MZ: 20.2 ± 6.02 DZ: 17.8 ± 2.75 |
40 MZ + 32 DZ (72 pairs; total = 144) | 70 F, 74 M | Serological | Digital dental casts | Heritability coefficient* | Maxillary intermolar width: 0.51 maxillary intercanine width: 1.04 Mandibular intermolar width: 0.65 Mandibular intercanine width: 0.78 Maxillary arch length: 1 Mandibular arch length: 0.57 |
| Kurushima et al.[44]/2015/Japan | MZ and DZ twins | 65.6 ± 10.3 | 116 MZ +16 DZ (132 pairs; total = 264) | 162 F, 102 M | Serological | Dental casts | Heritability coefficient and structural equation modelling | Maxillary interpremolar width: 0.28 Mandibular interpremolar width: 0.29 |
| Sidlauskas et al.[45]/2016/Lithuania | MZ and DZ twins | 21.73 ± 5.24 | 90 MZ + 51 DZ (141 pairs; total = 282) | 184 F, 98 M | DNA test (15 specific DNA markers) | Lateral cephalogram | Structural equation modelling | Overjet: 0 Overbite: 0.76 |
| Beltagy [46]/2017/Egypt | MZ twins | 3–5 (4.33 ± 0.7) | 20 MZ pairs (total = 40) | 24 F, 16 M | NR | Dental casts | Pearson correlation | Strong correlation for Arch width and length: 0.85 to 0.97, Molar relationship: 0.89, Canine relationship: 0.78. Moderate correlation for overbite (0.67) and overjet (0.57). |
| Anu et al. [47]/ 2018/India | MZ and DZ twins | 15–30 | 17 MZ + 13 DZ (30 pairs; total = 60) | NR | Medical records (Chorionicity and number of placental cords) |
Intra oral examination | Heritability coefficient* | Maxillary intercanine width: 0.23 Mandibular intercanine width: 0.16 Crowding: 0.29 Spacing: 1.43 Buccal segment relationship: 0.64 |
| Tiro et al.[48]/2019/Bosnia | MZ and DZ twins | 8.3–14.8 | 20 MZ + 32 DZ (52 pairs) (total = 104) | NR | Physical characteristics and by number of placentas on birth as reported by mother | Dental casts | t-test | Role of genetics on overjet and overbite could not confirmed (no significant difference between MZ and DZ twins) |
| Negishi et al.[17]/ 2020/Australia | MZ and DZ twins | MZ: 13.7 ± 1, DZ: 13.7 ± 0.8, OSDZ: 13.9 ± 0.9, range: 12–15 years | 45 MZ + 46 DZ (same sex) + 32 DZ (opposite sex) (123 pairs) (total = 246) | 124 F, 122 M | DNA from buccal cells | Digital dental casts | Heritability coefficient and structural equation modelling | Maxillary intermolar width: 0.86 Palatal depth: 0.86 |
| Kim et al[49]/ 2020/South Korea | MZ and DZ twins and siblings | 39.7 ± 9.26 | 36 MZ + 13DZ + 26 sibling pairs (75 pairs) (total = 150) | 82 F, 68 M | Questionnaire of zygosity diagnosis | Lateral cephalogram | Heritability coefficient | Functional occlusal plane to the SN plane: 0.52 Functional occlusal plane to the FH plane: 0.76 |
| Al-Qawasmi et al.[50]/ 2021/USA | Siblings | 12.7 | 148 siblings | 79 F, 69 M | NA | CBCT | Heritability coefficient | Curve of Wilson: 0.61 Curve of Spee: 1 |
| Babu et al.[51]/ 2022/India | MZ and DZ twins | 12–18 | 27 MZ + 24 DZ (51 pairs) (total = 102) | 52 F, 50 M | Facial appearance and history | Dental casts | t-test | No significant differences in arch length and arch width in both arches between MZ and DZ |
| Birant et al.[52]/ 2022/Turkey | MZ and DZ twins | MZ: 9.63, DZ: 9.47 | 59 MZ + 143 DZ (202 pairs) (total = 404) | 200 F, 204 M | NR | Dental casts | t-test, Mann–Whitney U test | Statistically significant differences in the dental arch parameters (length, width, and perimeter) among the MZ and DZ twins |
| Chaaban et al.[21]/2022/USA # | MZ and DZ twins | Mixed dentition (8–12), permanent dentition (13–16) | Mixed dentition 18 MZ +14 DZ (32 pairs) (total = 64) permanent dentition 18MZ + 19DZ (37 pairs) (total =74) |
Mixed dentition (32 F, 32 M) permanent dentition (33 F, 41 M) | NR | Digital dental casts | Heritability coefficient* | Mixed dentition Maxillary intermolar width: 0.06 maxillary intercanine width: −0.14 Permanent dentition Maxillary intermolar width: 0.43 maxillary intercanine width: 0.41 |
NA: not applicable, NR: not reported, MZ: monozygotic, DZ: dizygotic, OSDZ: opposite-sex dizygotic, F: females, M: males, CBCT: cone beam computed tomography, #: longitudinal studies, *: combined variance method used to calculate confidence interval of heritability coefficient.