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Orthodontic Department - Research

The Department of Orthodontics runs a postgraduate programme that trains 8 students in the speciality of Orthodontics, following the guidelines of the Erasmus programme. Each student completes a research project, as part of the programme requirements. In addition to the postgraduate students, the Department hosts doctoral students who follow a structured PhD programme. Currently there are 3 PhD students; five students have completed their PhD and defended their thesis during the past 2 years.

The Department of Orthodontics is involved in a diverse array of research projects. The main themes currently running are:

RCT on the efficacy of toothbrushing

A randomized, investigator-blinded, 3-month, parallel group clinical study to compare the efficacy of electric 3d toothbrushes versus manual toothbrushes in patients with fixed orthodontic appliances

This study evaluates if electric toothbrushes with a 3D action (rotation / oscillation and pulsation) are more effective than manual toothbrushes in removing plaque and reducing gingival inflammation in patients under orthodontic treatment with fixed appliances.
The trial is designed as a randomized, controlled, investigator blinded superiority trial, with two parallel groups and a 1:1 allocation ratio. Equal number of males and females will be allocated to each group.
One group of orthodontic patients will receive an electric toothbrush with orthodontic head and the other group will receive a manual orthodontic brush. Tooth brushing instructions will be provided. Measurements of two plaque indices and two gingival indices will be taken at baseline and at 3 monthly intervals.
The study has been registered in ClinicalTrials.gov (ClinicalTrials.gov ID: NCT02699931) and is a collaborative project with the Dept. of Periodontology.

  • Demetrios Halazonetis (PI)
  • Ioulia-Maria Mylonopoulou
  • Eudoxie Pepelassi
  • Phoebus Madianos

Dental and craniofacial morphology

Dental and craniofacial morphology shows wide variability in humans. The genetic basis of this variability is not known, although a large number of genes are implicated in dentofacial development. We are investigating dental and craniofacial morphology in children and adults using dental casts, photographs and cephalometric radiographs. Our aims are: a) to describe variability patterns of the teeth and the craniofacial skeleton, b) to investigate the covariation between teeth and the craniofacial skeleton, and between different regions of the craniofacial skeleton, and c) to investigate the genetic basis of dental and craniofacial variability. In addition to conventional measurement methods, we use geometric morphometrics to study shape. Teeth are scanned with a 3D scanner and more than 200 landmarks (including semi-landmarks on curves and surfaces) are placed on the occlusal surfaces to obtain a comprehensive dataset of their anatomy. Similarly, we use semi-landmarks on anatomic curves identified on cephalometric radiographs to acquire craniofacial anatomy in higher detail than conventional cephalometrics. We plan to integrate these data with genetic data, in search of potential associations between genetic loci and craniofacial shape. To this aim we will identify individuals with extreme morphological patterns as well as orthodontic patients, and their families, with partial anodontia. This research will be a collaborative effort with the Departments of Basic Biomedical Sciences and of Oral Biology.

Relevant publications:

Shape variation and covariation of upper and lower dental arches of an orthodontic population.
Papagiannis A, Halazonetis DJ.
Eur J Orthod 2015. doi: 10.1093/ejo/cjv019

Correlation of 2D:4D Ratio and Craniofacial Shape in Prepubertal Children.
Valla K, Halazonetis DJ.
Am J Hum Biol 2014. doi: 10.1002/ajhb.22512

Geometric morphometric 3D shape analysis and covariation of human mandibular and maxillary first molars.
Polychronis G, Christou P, Mavragani M, Halazonetis DJ.
Am J Phys Anthropol 2013;152:186-96. doi: 10.1002/ajpa.22340

Geometric morphometric analysis of craniofacial variation, ontogeny and modularity in a cross-sectional sample of modern humans.
Wellens HL, Kuijpers-Jagtman AM, Halazonetis DJ.
J Anat 2013;222:397-409. doi: 10.1111/joa.12027
This project was a collaboration with the Department of Orthodontics and Craniofacial Biology, Radboud University Nijmegen, Medical Centre Nijmegen, The Netherlands.

Morphological integration between the cranial base and the face in children and adults.
Gkantidis N, Halazonetis DJ.
J Anat 2011;218:426-38. doi: 10.1111/j.1469-7580.2011.01346.x


Biomechanics and Orthodontic materials

Newer materials present new challenges because of the potential for interaction. Moreover, new testing techniques provide additional information on widely used biomaterials. Our aims are to evaluate a) the forces and moment created by different orthodontic biomechanical systems, b) the influence of orthodontic materials on the surface characteristics of the enamel, c) the effect of intraoral aging on the material properties and d) the in vitro behavior of different types of fixed retainers, mini-implants and lingual brackets.

Relevant publications:

Morphological and structural characteristics of orthodontic mini-implants.
AlSamak S, Bitsanis E, Makou M, Eliades G.
J Orofac Orthop 2012;73:58-71. doi: 10.1007/s00056-011-0061-0

A comparative assessment of the forces and moments generated with various maxillary incisor intrusion biomechanics.
Sifakakis I, Pandis N, Makou M, Eliades T, Bourauel C.
Eur J Orthod 2010;32:159-64. doi: 10.1093/ejo/cjp089

Comparative assessment of the roughness, hardness, and wear resistance of aesthetic bracket materials.
Zinelis S, Eliades T, Eliades G, Makou M, Silikas N.
Dent Mater 2005;21:890-4. doi: 10.1016/j.dental.2005.03.007

Comparative study of the effect of in vitro and in vivo aging on morphology, microstructure and elemental composition of Nickel- Titanium orthodontic archwires.
Zinelis S, Makou M, Gioka C, Eliades T.
Hellenic Orthodontic Review 2003;6:45-58. [PDF]
This paper received the 2004 European Federation of Orthodontics (FEO) award for the best scientific research published in European Journals in the field of Orthodontics.


Selected Publications


  • Paoloni V, Lione R, Farisco F, Halazonetis DJ, Franchi L, Cozza P. Morphometric covariation between palatal shape and skeletal pattern in Class II growing subjects. Eur J Orthod 2017. doi: 10.1093/ejo/cjx014.
  • Sampaziotis D, Tsolakis IA, Bitsanis E, Tsolakis AI. Open versus closed surgical exposure of palatally impacted maxillary canines: comparison of the different treatment outcomes-a systematic review. Eur J Orthod 2017. doi: 10.1093/ejo/cjw077.
  • Sifakakis I, Eliades T. Adverse reactions to orthodontic materials. Aust Dent J 2017;62 Suppl 1:20-28. doi: 10.1111/adj.12473.
  • Sifakakis I, Zinelis S, Patcas R, Eliades T. Mechanical properties of contemporary orthodontic adhesives used for lingual fixed retention. Biomed Tech (Berl) 2017;62(3):289-294. doi: 10.1515/bmt-2015-0165.
  • Hersche S, Sifakakis I, Zinelis S, Eliades T. Elemental, microstructural, and mechanical characterization of high gold orthodontic brackets after intraoral aging. Biomed Tech (Berl) 2017;62(1):97-102. doi: 10.1515/bmt-2015-0205.
  • Karamesinis K, Spyropoulou A, Dalagiorgou G, Katsianou MA, Nokhbehsaim M, Memmert S, Deschner J, Vastardis H, Piperi C. Continuous hydrostatic pressure induces differentiation phenomena in chondrocytes mediated by changes in polycystins, SOX9, and RUNX2. J Orofac Orthop 2017;78(1):21-31. doi: 10.1007/s00056-016-0061-1.


  • Katsadouris A, Halazonetis DJ. Geometric morphometric analysis of craniofacial growth between the ages of 12 and 14 in normal humans. Eur J Orthod 2016. doi: 10.1093/ejo/cjw070.
  • Parcha E, Bitsanis E, Halazonetis DJ. Morphometric covariation between palatal shape and skeletal pattern in children and adolescents: a cross-sectional study. Eur J Orthod 2016. doi: 10.1093/ejo/cjw063.
  • Cocos A, Halazonetis DJ. Craniofacial shape differs in patients with tooth agenesis: geometric morphometric analysis. Eur J Orthod 2016. doi: 10.1093/ejo/cjw049.
  • Halazonetis DJ. "The choice is ours" (not to mention our patients'). Am J Orthod Dentofacial Orthop 2016;149:590-1. doi: 10.1016/j.ajodo.2016.02.004.
  • Karell MA, Langstaff HK, Halazonetis DJ, Minghetti C, Frelat M, Kranioti EF. A novel method for pair-matching using three-dimensional digital models of bone: mesh-to-mesh value comparison. Int J Legal Med 2016;130(5):1315-22. doi: 10.1007/s00414-016-1334-3.
  • Livas C, Halazonetis DJ, Booij JW, Katsaros C, Ren Y. Does fixed retention prevent overeruption of unopposed mandibular second molars in maxillary first molar extraction cases? Prog Orthod 2016;17:6. doi: 10.1186/s40510-016-0119-z.
  • Mousoulea S, Tsolakis I, Ferdianakis E, Tsolakis AI. The Effect of Chin-cup Therapy in Class III Malocclusion: A Systematic Review. Open Dent J 2016;10:664-679. doi: 10.2174/1874210601610010664.
  • Papageorgiou SN, Sifakakis I, Keilig L, Patcas R, Affolter S, Eliades T, Bourauel C. Torque differences according to tooth morphology and bracket placement: a finite element study. Eur J Orthod 2016. doi: 10.1093/ejo/cjw074.
  • Papageorgiou SN, Sifakakis I, Doulis I, Eliades T, Bourauel C. Torque efficiency of square and rectangular archwires into 0.018 and 0.022 in. conventional brackets. Prog Orthod 2016;17:5. doi: 10.1186/s40510-016-0118-0.
  • Katsianou MA, Adamopoulos C, Vastardis H, Basdra EK. Signaling mechanisms implicated in cranial sutures pathophysiology: Craniosynostosis. BBA Clin 2016;6:165-176. doi: 10.1016/j.bbacli.2016.04.006.
  • Fanourakis G, Tosios K, Papanikolaou N, Chatzistamou I, Xydous M, Tseleni-Balafouta S, Sklavounou A, Voutsinas GE, Vastardis H. Evidence for APOBEC3B mRNA and protein expression in oral squamous cell carcinomas. Exp Mol Pathol 2016;101(3):314-319. doi: 10.1016/j.yexmp.2016.11.001.


  • Sifakakis I, Eliades T, Bourauel C. Residual stress analysis of fixed retainer wires after in vitro loading: can mastication-induced stresses produce an unfavorable effect? Biomed Tech (Berl) 2015;60:617-22. doi: 10.1515/bmt-2015-0013.
  • Kloukos D, Sifakakis I, Voutsa D, Doulis I, Eliades G, Katsaros C, Eliades T. BPA qualtitative and quantitative assessment associated with orthodontic bonding in vivo. Dent Mater 2015;31:887-94. doi: 10.1016/j.dental.2015.04.020.
  • Akli E, Marinaki L, Halazonetis DJ. Selecting subjects with high craniofacial shape homogeneity for clinical trials. Am J Orthod Dentofacial Orthop 2015;148:1026-35. doi: 10.1016/j.ajodo.2015.05.033.
  • Angelopoulou MV, Koletsi D, Vadiakas G, Halazonetis DJ. Induced ankylosis of a primary molar for skeletal anchorage in the mandible as alternative to mini-implants. Prog Orthod 2015;16:18. doi: 10.1186/s40510-015-0090-0.
  • Salih Al Qassar SS, Mavragani M, Psarras V, Halazonetis DJ. The anterior component of occlusal force revisited: direct measurement and theoretical considerations. Eur J Orthod 2015. doi: 10.1093/ejo/cjv028.
  • Papagiannis A, Halazonetis DJ. Shape variation and covariation of upper and lower dental arches of an orthodontic population. Eur J Orthod 2015. doi: 10.1093/ejo/cjv019.


  • Zinelis S, Sifakakis I, Katsaros C, Eliades T. Microstructural and mechanical characterization of contemporary lingual orthodontic brackets. Eur J Orthod 2014;36:389-93. doi: 10.1093/ejo/cjt086.
  • Danz JC, Greuter C, Sifakakis I, Fayed M, Pandis N, Katsaros C. Stability and relapse after orthodontic treatment of deep bite cases-a long-term follow-up study. Eur J Orthod 2014;36:522-30. doi: 10.1093/ejo/cjs079.
  • Pavli M, Farmaki E, Merkourea S, Vastardis H, Sklavounou A, Tzerbos F, Chatzistamou I. Endoplasmic Reticulum Stress-Associated Chaperones, Bip/GRP78 and Calnexin are Overexpressed in Keratocystic Odontogenic Tumours. J Oral Maxillofac Res 2014;5:e3. doi: 10.5037/jomr.2014.5103.
  • Lempesi E, Karamolegkou M, Pandis N, Mavragani M. Maxillary canine impaction in orthodontic patients with and without agenesis: a cross-sectional radiographic study. Angle Orthod 2014;84:11-7. doi: 10.2319/022413-155.1.
  • Lempesi E, Pandis N, Fleming PS, Mavragani M. A comparison of apical root resorption after orthodontic treatment with surgical exposure and traction of maxillary impacted canines versus that without impactions. Eur J Orthod 2014;36:690-7. doi: 10.1093/ejo/cjt099.
  • Papagrigorakis MJ, Toulas P, Tsilivakos MG, Kousoulis AA, Skorda D, Orfanidis G, Synodinos PN. Neurosurgery During the Bronze Age: A Skull Trepanation in 1900 BC Greece. World Neurosurg 2014;81:431-435. doi: 10.1016/j.wneu.2013.01.044.
  • Sifakakis I, Pandis N, Makou M, Eliades T, Katsaros C, Bourauel C. Torque efficiency of different archwires in 0.018- and 0.022-inch conventional brackets. Angle Orthod 2014;84:149-54. doi: 10.2319/021713-138.1.
  • Valla K, Halazonetis DJ. Correlation of 2D:4D digit ratio and craniofacial shape in prepubertal children. Am J Hum Biol 2014;26:337-346. doi: 10.1002/ajhb.22512.
  • Vasoglou M, Chrysomali E, Zinelis S, Bitsanis I, Haralambakis N, Makou M, Epsilonliades G. Retrieval analysis of immediately loaded orthodontic mini-implants: material and tissue characterization. Eur J Orthod 2014;36:683-9. doi: 10.1093/ejo/cjt097.
  • Lyros I, Fora E, Damaskos S, Stanko P, Tsolakis A. An incidental finding on a diagnostic CBCT: a case report. Aust Orthod J 2014;30:67-71.


  • Halazonetis DJ, Schimmel M, Antonarakis GS, Christou P. Novel software for quantitative evaluation and graphical representation of masticatory efficiency. J Oral Rehabil 2013;40:329-35. doi: 10.1111/joor.12043.
  • Konstantonis D, Anthopoulou C, Makou M. Extraction decision and identification of treatment predictors in Class I malocclusions. Prog Orthod 2013;14:47. doi: 10.1186/2196-1042-14-47.
  • Konstantonis D, Papadopoulou A, Makou M, Eliades T, Basdra EK, Kletsas D. Senescent human periodontal ligament fibroblasts after replicative exhaustion or ionizing radiation have a decreased capacity towards osteoblastic differentiation. Biogerontology 2013;14:741-51. doi: 10.1007/s10522-013-9449-0.
  • Livas C, Halazonetis DJ, Booij JW, Pandis N, Tu YK, Katsaros C. Maxillary sinus floor extension and posterior tooth inclination in adolescent patients with Class II Division 1 malocclusion treated with maxillary first molar extractions. Am J Orthod Dentofacial Orthop 2013;143:479-85. doi: 10.1016/j.ajodo.2012.10.024.
  • Papagrigorakis MJ, Synodinos PN, Stathi A, Skevaki CL, Zachariadou L. The plague of Athens: an ancient act of bioterrorism? Biosecur Bioterror 2013;11:228-9. doi: 10.1089/bsp.2013.0057.
  • Polychronis G, Christou P, Mavragani M, Halazonetis DJ. Geometric morphometric 3D shape analysis and covariation of human mandibular and maxillary first molars. Am J Phys Anthropol 2013;152:186-96. doi: 10.1002/ajpa.22340.
  • Sifakakis I, Pandis N, Makou M, Eliades T, Katsaros C, Bourauel C. A comparative assessment of torque generated by lingual and conventional brackets. Eur J Orthod 2013;35:375-80. doi: 10.1093/ejo/cjs029.
  • Sifakakis I, Pandis N, Makou M, Eliades T, Katsaros C, Bourauel C. Torque expression of 0.018 and 0.022 inch conventional brackets. Eur J Orthod 2013;35:610-4. doi: 10.1093/ejo/cjs041.
  • Sifakakis I, Pandis N, Makou M, Katsaros C, Eliades T, Bourauel C. A comparative assessment of forces and moments generated by lingual and conventional brackets. Eur J Orthod 2013;35:82-6. doi: 10.1093/ejo/cjr048.
  • Wellens HL, Kuijpers-Jagtman AM, Halazonetis DJ. Geometric morphometric analysis of craniofacial variation, ontogeny and modularity in a cross-sectional sample of modern humans. J Anat. 2013;222:397-409. doi: 10.1111/joa.12027.


  • Ali O, Makou M, Papadopoulos T, Eliades G. Laboratory evaluation of modern plastic brackets. Eur J Orthod 2012;34:595-602. [PubMed].
  • AlSamak S, Bitsanis E, Makou M, Eliades G. Morphological and structural characteristics of orthodontic mini-implants. J Orofac Orthop 2012;73:58-71. doi: 10.1007/s00056-011-0061-0.
  • Angelopoulou MV, Vlachou V, Halazonetis DJ. Pharmacological management of pain during orthodontic treatment: a meta-analysis. Orthod Craniofac Res 2012;15:71-83. doi: 10.1111/j.1601-6343.2012.01542.x. doi: 10.1111/j.1601-6343.2012.01542.x.
  • Bartzela T, Katsaros C, Rønning E, Rizell S, Semb G, Bronkhorst E, Halazonetis D, Kuijpers-Jagtman AM. A longitudinal three-center study of craniofacial morphology at 6 and 12 years of age in patients with complete bilateral cleft lip and palate. Clin Oral Investig 2012;16:1313-24. doi: 10.1007/s00784-011-0615-y.
  • Halazonetis DJ. Cone-beam computed tomography is not the imaging technique of choice for comprehensive orthodontic assessment. Am J Orthod Dentofacial Orthop 2012;141:403, 405, 407 passim. doi: 10.1016/j.ajodo.2012.02.010. doi: 10.1016/j.ajodo.2012.02.010.
  • Papagrigorakis MJ, Karamesinis KG, Daliouris KP, Kousoulis AA, Synodinos PN, Hatziantoniou MD. Paleopathological findings in radiographs of ancient and modern Greek skulls. Skeletal Radiol 2012;41:1605-11. doi: 10.1007/s00256-012-1432-3.
  • Papagrigorakis MJ, Karamolegou M, Vilos G, Apostolidis C, Karamesinis K, Synodinos PN. Auriculo-condylar syndrome. Angle Orthod 2012;82:556-64. doi: 10.2319/052911-356.1.
  • Papaioannou W, Panagopoulos A, Koletsi-Kounari H, Kontou E, Makou M. Adhesion of Porphyromonas gingivalis and Biofilm Formation on Different Types of Orthodontic Brackets. Int J Dent 2012;2012:471380. doi: 10.1155/2012/471380.
  • Tsolakis AI, Khaldi L, Bitsanis I, Makou M, Dontas IA. Distraction-like phenomena in maxillary bone due to application of orthodontic forces in ovariectomized rats. Indian J Dent Res 2012;23:501-5. doi: 10.4103/0970-9290.104958.