Korean J Orthod.  2021 Nov;51(6):407-418. 10.4041/kjod.2021.51.6.407.

Differences in the heritability of craniofacial skeletal and dental characteristics between twin pairs with skeletal Class I and II malocclusions

Affiliations
  • 1Department of Orthodontics, School of Dentistry, Seoul National University, Seoul, Korea
  • 2Biomedical Knowledge Engineering Laboratory, School of Dentistry, Seoul National University, Seoul, Korea
  • 3Department of Epidemiology, School of Public Health, Seoul National University, Seoul, Korea
  • 4Department of Family Medicine, Samsung Medical Center and Center for Clinical Research, Samsung Biomedical Research Institute, Sungkyunkwan University School of Medicine, Seoul, Korea
  • 5Department of Orthodontics, Institute of Oral Health Science, Ajou University School of Medicine, Suwon, Korea
  • 6Department of Orthodontics, School of Dentistry and Dental Research Institute, Seoul National University, Seoul, Korea

Abstract


Objective
To investigate differences in the heritability of skeletodental characteristics between twin pairs with skeletal Class I and Class II malocclusions.
Methods
Forty Korean adult twin pairs were divided into Class I (C-I) group (0° ≤ angle between point A, nasion, and point B [ANB]) ≤ 4°; mean age, 40.7 years) and Class II (C-II) group (ANB > 4°; mean age, 43.0 years). Each group comprised 14 monozygotic and 6 dizygotic twin pairs. Thirty-three cephalometric variables were measured using lateral cephalograms and were categorized as the anteroposterior, vertical, dental, mandible, and cranial base characteristics. The ACE model was used to calculate heritability (A > 0.7, high heritability). Thereafter, principal component analysis (PCA) was performed.
Results
Twin pairs in C-I group exhibited high heritability values in the facial anteroposterior characteristics, inclination of the maxillary and mandibular incisors, mandibular body length, and cranial base angles. Twin pairs in C-II group showed high heritability values in vertical facial height, ramus height, effective mandibular length, and cranial base length. PCA extracted eight components with 88.3% in the C-I group and seven components with 91.0% cumulative explanation in the C-II group.
Conclusions
Differences in the heritability of skeletodental characteristics between twin pairs with skeletal Class I and II malocclusions might provide valuable information for growth prediction and treatment planning.

Keyword

Heritability; Twins; ACE model; Principal component analysis

Figure

  • Figure 1 Landmarks and reference lines used in the cephalometric analysis. Landmarks: S, sella; N, nasion; Po, porion; Or, orbitale; CD, condylion; Ar, articulare; Ba, basion; PNS, posterior nasal spine; ANS, anterior nasal spine; A, A point; B, B point; Pog, pogonion; Gn, gnathion; Me, menton; Go, gonion; Reference lines: SN plane; Frankfort-horizontal (FH) plane; palatal plane (PP); occlusal plane (OP); mandibular plane (MP); N perpendicular line; U1, long axis of the upper incisor; L1, long axis of the lower incisor.

  • Figure 2 Cephalometric variables. Anteroposterior characteristics: 1, SNA (angle between S, N, and point A); 2, SNB (angle between S, N, and point B); 3, ANB (angle between point A, N, and point B); 4, NA-Pog (angle between N, point A, and Pog); 5, FH-NPog (angle formed by FH plane and N-Pog line); 6, A-N perpendicular (perpendicular distance from point A to the N perpendicular line); 7, Pog-N perpendicular (perpendicular distance from Pog to the N perpendicular line); and 8, mandibular body length/anterior cranial base (ratio of the distance between Go and Me to the distance between S and N). Vertical characteristics: 1, FH-PP (angle formed by FH plane and palatal plane); 2, FMA (angle formed by FH plane and mandibular plane); 3, PP-MP (angle formed by PP and MP); 4, Bjork sum (summation of angles determined by saddle angle, articular angle, and gonial angle); 5, N-Me (distance between N and Me); 6, S-Go (distance between S and Go); and 7, N-ANS/ANS-Me (ratio of the distance between N and ANS to the distance between ANS and Me). Dental characteristics: 1, U1-FH (angle formed by upper incisor axis and FH plane); 2, U1-PP (angle formed by U1 and PP); 3, U1-OP (angle formed by U1 and OP); 4, IMPA (angle formed by lower incisor axis and MP); 5, L1-OP (angle formed by L1 and OP); 6, interincisal angle (angle formed by U1 and L1); 7, FH-OP (angle formed by FH plane and OP); and 8, OP-MP (angle formed by OP and MP). Mandible characteristics: 1, gonial angle (angle between Ar, Go, and Me); 2, upper gonial angle (angle between Ar, Go, and N); 3, CD-Gn (distance between condyle head and Gn); 4, Go-Me (distance between Go and Me); and 5, Ar-Go (distance between Ar and Go). Cranial base characteristics: 1, saddle angle (angle between N, S, and Ar); 2, cranial base angle (angle between N, S, and Ba); 3, S-N (distance between S and N); 4, S-Ar (distance between S and Ar); and 5, Ar-N (distance between Ar and N). See Figure 1 for definition of each landmark.


Reference

1. Ricketts RM. 1960; The influence of orthodontic treatment on facial growth and development. Angle Orthod. 30:103–33.
2. Ricketts RM. 1972; A principle of arcial growth of the mandible. Angle Orthod. 42:368–86. DOI: 10.1043/0003-3219(1972)042<0368:APOAGO>2.0.CO;2. PMID: 4507153.
3. Johnston LE. 1975; A simplified approach to prediction. Am J Orthod. 67:253–7. DOI: 10.1016/0002-9416(75)90048-2. PMID: 1054908.
Article
4. Ricketts RM. 1981; Perspectives in the clinical application of cephalometrics. The first fifty years. Angle Orthod. 51:115–50. DOI: 10.1043/0003-3219(1981)051<0115:PITCAO>2.0.CO;2. PMID: 6942666.
5. Nakasima A, Ichinose M, Nakata S, Takahama Y. 1982; Hereditary factors in the craniofacial morphology of Angle's Class II and Class III malocclusions. Am J Orthod. 82:150–6. DOI: 10.1016/0002-9416(82)90493-6.
Article
6. Lundström A, McWilliam JS. 1987; A comparison of vertical and horizontal cephalometric variables with regard to heritability. Eur J Orthod. 9:104–8. DOI: 10.1093/ejo/9.2.104. PMID: 3472887.
7. Fishman L. Fishman LS, Subtelny JD, editors. 2000. Maturational development and facial form relative to treatment timing. Early orthodontic treatment. Quintessence;Chicago:
8. Barbosa LAG, Araujo E, Behrents RG, Buschang PH. 2017; Longitudinal cephalometric growth of untreated subjects with Class II Division 2 malocclusion. Am J Orthod Dentofacial Orthop. 151:914–20. DOI: 10.1016/j.ajodo.2016.10.026. PMID: 28457269.
Article
9. Bouchard TJ, Propping P. 1993. Twins as a tool of behavioral genetics. Wiley;London:
10. Neale MC, Cardon LR. 1992. Methodology for genetic studies of twins and families. Kluwer Academic Publishers;Boston: DOI: 10.1007/978-94-015-8018-2.
11. Martin N, Boomsma D, Machin G. 1997; A twin-pronged attack on complex traits. Nat Genet. 17:387–92. DOI: 10.1038/ng1297-387. PMID: 9398838.
Article
12. Hunter WS. 1965; A study of the inheritance of craniofacial characteristics as seen in lateral cephalograms of 72 like-sexed twins. Rep Congr Eur Orthod Soc. 41:59–70. PMID: 5222375.
13. Nakata M, Yu PL, Davis B, Nance WE. 1974; Genetic determinants of cranio-facial morphology: a twin study. Ann Hum Genet. 37:431–43. DOI: 10.1111/j.1469-1809.1974.tb01848.x. PMID: 4472123.
Article
14. Manfredi C, Martina R, Grossi GB, Giuliani M. 1997; Heritability of 39 orthodontic cephalometric parameters on MZ, DZ twins and MN-paired singletons. Am J Orthod Dentofacial Orthop. 111:44–51. DOI: 10.1016/S0889-5406(97)70301-9. PMID: 9009923.
Article
15. Savoye I, Loos R, Carels C, Derom C, Vlietinck R. 1998; A genetic study of anteroposterior and vertical facial proportions using model-fitting. Angle Orthod. 68:467–70. DOI: 10.1043/0003-3219(1998)068<0467:AGSOAA>2.3.CO;2. PMID: 9770105.
16. Carels C, Van Cauwenberghe N, Savoye I, Willems G, Loos R, Derom C, et al. 2001; A quantitative genetic study of cephalometric variables in twins. Clin Orthod Res. 4:130–40. DOI: 10.1034/j.1600-0544.2001.040303.x. PMID: 11553097.
Article
17. Peng J, Deng H, Cao C, Ishikawa M. 2005; Craniofacial morphology in Chinese female twins: a semi-longitudinal cephalometric study. Eur J Orthod. 27:556–61. DOI: 10.1093/ejo/cji059. PMID: 16257991.
Article
18. Amini F, Borzabadi-Farahani A. 2009; Heritability of dental and skeletal cephalometric variables in monozygous and dizygous Iranian twins. Orthod Waves. 68:72–9. DOI: 10.1016/j.odw.2009.01.001.
Article
19. Šidlauskas M, Šalomskienė L, Andriuškevičiūtė I, Šidlauskienė M, Labanauskas Ž, Vasiliauskas A, et al. 2016; Heritability of mandibular cephalometric variables in twins with completed craniofacial growth. Eur J Orthod. 38:493–502. DOI: 10.1093/ejo/cjv062. PMID: 26503948.
Article
20. Kim E, Sung J, Song YM, Chae HS, Mo SS, Kim YH, et al. 2018; Heritability of facial skeletal and dental characteristics of monozygotic and dizygotic twins using cephalometric analysis and Falconer's method. J Craniofac Surg. 29:e274–9. DOI: 10.1097/SCS.0000000000004313. PMID: 29419588.
Article
21. Song J, Chae HS, Shin JW, Sung J, Song YM, Baek SH, et al. 2019; Influence of heritability on craniofacial soft tissue characteristics of monozygotic twins, dizygotic twins, and their siblings using Falconer's method and principal components analysis. Korean J Orthod. 49:3–11. DOI: 10.4041/kjod.2019.49.1.3. PMID: 30603620. PMCID: PMC6306317.
Article
22. Kim DK, Sung J, Song YM, Kim EM, Kim YH, Baek SH. 2019; Differences in heritability of craniofacial skeletal and dental characteristics between hypo- and hyper-divergent patterns using Falconer's method and principal component analysis. Angle Orthod. 89:242–51. DOI: 10.2319/062518-475.1. PMID: 30516415. PMCID: PMC8120887.
Article
23. Javaras KN, Hudson JI, Laird NM. 2010; Fitting ACE structural equation models to case-control family data. Genet Epidemiol. 34:238–45. DOI: 10.1002/gepi.20454. PMID: 19918760. PMCID: PMC2922975.
Article
24. Harris EF, Johnson MG. 1991; Heritability of craniometric and occlusal variables: a longitudinal sib analysis. Am J Orthod Dentofacial Orthop. 99:258–68. DOI: 10.1016/0889-5406(91)70007-J. PMID: 1998301.
Article
25. Nascimento GC, Magno MB, Heo G, Normando D. 2014; How can I explore high-dimensional data? Dental Press J Orthod. 19:14–5. DOI: 10.1590/2176-9451.19.6.014-015.ebo. PMID: 25628075. PMCID: PMC4347406.
Article
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