Evaluation of crown inclination and angulation after orthodontic treatment using digital models

Comparison to the prescription of the brackets used
  • Iury Oliveira Castro
  • Bruno Frazão Gribel
  • Ana Helena Gonçalves de Alencar
  • José Valladares-Neto
  • Carlos Estrela
Original Article



To compare crown inclination and angulation results obtained after orthodontic treatment to the Roth prescription.


The study design was based on files and documents obtained from a database of 26 patients who had undergone orthodontic treatment using the straight-wire technique and the Roth prescription. The crown inclination and angulation were measured using a three-dimensional (3D) cephalometric module (VistaDent, Dentsply, New York, NY, USA) by an orthodontist. A coordinate system (x, y, z) was developed for each tooth that used the Andrews plane as a para-axial reference. Descriptive statistical analysis provided the mean and standard deviation (SD) of crown inclination and angulation obtained after orthodontic treatment, which were compared to the Roth prescription.


Method reproducibility is an important test to investigate the margin of error and to verify the reliability of results. The results at time 1 (1.6° ± 1.1°) and time 2 (1.7° ± 1.2°) of the pilot study were not statistically different (p = 0.99). Maxillary lateral and central incisors presented significant differences in crown angulation (p < 0.05) compared to the Roth prescription. The crown angulation of maxillary second premolars with regard to the occlusal plane presented a similar value to the Roth prescription.


Crown inclination and angulation found at the end of orthodontic treatment did not match the prescription of the brackets for most teeth, as measured using digital models.


Cone beam computed tomography Cephalometry Orthodontics Torque Roth prescription 

Digitale Evaluation von Kroneninklination und -angulation nach kieferorthopädischer Behandlung

Vergleich mit der Bracket-Prescription nach Roth



Inklination und Angulation der Zahnkronen nach kieferorthopädischer Behandlung sollten mit der Roth-Prescription verglichen werden


In der retrospektiven Studie wurden Befunde und Datensätze von 26 Patienten ausgewertet, die in Straight-wire-Technik mit dem Roth-System behandelt worden waren. Inklination und Angulation der Kronen wurde mit einem dreidimensionalen kephalometrischen Modul (VistaDent, Dentsply, New York/NY, USA) durch einen Kieferorthopäden vermessen. Für jeden Zahn wurde ein Koordinatensystem (x, y, z) erstellt, wobei die Andrews-Ebene als paraaxiale Referenzebene diente. Mittels deskriptiver Analyse wurden nach Abschluss der kieferorthopädischen Behandlung Durchschnittswerte und Standardabweichungen (SD) von Kroneninklination und -angulation ermittelt und den vorgesehenen Werten des Roth-Systems gegenübergestellt.


Die Reproduzierbarkeit einer Methode zur prüfen ist wichtig, um die Fehlerquote zu ermitteln und ihre Verlässlichkeit zu verifizieren. In der Pilotstudie gab es zwischen den Ergebnissen zu den Zeitpunkten 1 (1,6° ± 1,1°) und 2 (1,7° ± 1,2°) keine statistisch signifikanten Unterschiede (p = 0,99). Die zentralen und lateralen Oberkieferinzisivi wiesen im Vergleich zum Roth-System signifikante Unterschiede in der Angulation auf (p < 0,05). Die Angulation der zweiten Prämolaren im Oberkiefer zeigte hinsichtlich der Okklusionsebene einen dem Roth-System ähnlichen Wert.


Kroneninklination und -angulation, wie sie sich nach Beendigung der kieferorthopädischen Behandlung in der Vermessung digitaler Modelle darstellten, entsprach bei den meisten Zähnen nicht den Werten, die vor der Behandlung geplant waren.


Digitale Volumentomographie Kephalometrie Kieferorthopädie Torque Bracket-Prescription nach Roth 



The authors would like to thank Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) for the financial support to this research (no. 1223742).


The work was supported by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) in São Paulo, Brazil.

Compliance with ethical guidelines

Conflict of interest

I.O. Castro, B. Frazão Gribel, A.H.G. Alencar, J. Valladares-Neto and C. Estrela declare that they have no competing interests.

Ethical standards

This study was approved by the Ethics Committee of Local Research (Universidade Federal de Goiás, Brazil, Proc. no. 392.806).


  1. 1.
    Alexander RG (1983) The vari-simplex discipline, part 1: concept and appliance design. J Clin Orthod 17:380–395PubMedGoogle Scholar
  2. 2.
    American Academy of Oral and Maxillofacial Radiology (2013) Clinical recommendations regarding use of cone beam computed tomography in orthodontics. [corrected]. Position statement by the American Academy of Oral and Maxillofacial Radiology. Oral Surg Oral Med Oral Pathol Oral Radiol 116:238–257CrossRefGoogle Scholar
  3. 3.
    Andrews LF (1972) The six keys to normal occlusion. Am J Orthod 62:296–309CrossRefPubMedGoogle Scholar
  4. 4.
    Andrews LF (1976) The straight-wire appliance. Case histories: nonextraction. J Clin Orthod 10:282–303PubMedGoogle Scholar
  5. 5.
    Andrews LF (1976) The straight-wire appliance. Explained and compared. J Clin Orthod 10:174–195PubMedGoogle Scholar
  6. 6.
    Andrews LF (1976) The straight-wire appliance. Extraction brackets and “classification of treatment”. J Clin Orthod 10:360–379PubMedGoogle Scholar
  7. 7.
    Andrews LF (1976) The straight-wire appliance: origin, controversy, commentary. J Clin Orthod 10:99–114PubMedGoogle Scholar
  8. 8.
    Archambault A, Major TW, Carey JP et al (2010) A comparison of torque expression between stainless steel, titanium molybdenum alloy, and copper nickel titanium wires in metallic self-ligating brackets. Angle Orthod 80:884–889CrossRefPubMedGoogle Scholar
  9. 9.
    Bouwens DG, Cevidanes L, Ludlow JB et al (2011) Comparison of mesiodistal root angulation with posttreatment panoramic radiographs and cone-beam computed tomography. Am J Orthod Dentofacial Orthop 139:126–132CrossRefPubMedPubMedCentralGoogle Scholar
  10. 10.
    Cash AC, Good SA, Curtis RV et al (2004) An evaluation of slot size in orthodontic brackets—are standards as expected? Angle Orthod 74:450–453PubMedGoogle Scholar
  11. 11.
    Germane N, Bentley BE Jr, Isaacson RJ (1989) Three biologic variables modifying faciolingual tooth angulation by straight-wire appliances. Am J Orthod Dentofacial Orthop 96:312–319CrossRefPubMedGoogle Scholar
  12. 12.
    Gioka C, Eliades T (2004) Materials-induced variation in the torque expression of preadjusted appliances. Am J Orthod Dentofacial Orthop 125:323–328CrossRefPubMedGoogle Scholar
  13. 13.
    Hans MG, Kishiyama C, Parker SH et al (1994) Cephalometric evaluation of two treatment strategies for deep overbite correction. Angle Orthod 64:265–274PubMedGoogle Scholar
  14. 14.
    Horner K, Islam M, Flygare L et al (2009) Basic principles for use of dental cone beam computed tomography: consensus guidelines of the European Academy of Dental and Maxillofacial Radiology. Dentomaxillofac Radiol 38:187–195CrossRefPubMedGoogle Scholar
  15. 15.
    Joch A, Pichelmayer M, Weiland F (2010) Bracket slot and archwire dimensions: manufacturing precision and third order clearance. J Orthod 37:241–249CrossRefPubMedGoogle Scholar
  16. 16.
    McLaughlin RP, Bennet JC (1995) Bracket placement with the preadjusted appliance. J Clin Orthod 29:302–311PubMedGoogle Scholar
  17. 17.
    Moesi B, Dyer F, Benson PE (2013) Roth versus MBT: does bracket prescription have an effect on the subjective outcome of pre-adjusted edgewise treatment? Eur J Orthod 35:236–243CrossRefPubMedGoogle Scholar
  18. 18.
    Peck JL, Sameshima GT, Miller A et al (2007) Mesiodistal root angulation using panoramic and cone beam CT. Angle Orthod 77:206–213CrossRefPubMedGoogle Scholar
  19. 19.
    Peck S (2009) The contributions of Edward H. Angle to dental public health. Community Dent Health 26:130–131PubMedGoogle Scholar
  20. 20.
    Ricketts RM (1976) Bioprogressive therapy as an answer to orthodontic needs. Part I. Am J Orthod 70:241–268CrossRefPubMedGoogle Scholar
  21. 21.
    Roth RH (1987) The straight-wire appliance 17 years later. J Clin Orthod 21:632–642PubMedGoogle Scholar
  22. 22.
    Shewinvanakitkul W, Hans MG, Narendran S et al (2011) Measuring buccolingual inclination of mandibular canines and first molars using CBCT. Orthod Craniofac Res 14:168–174CrossRefPubMedGoogle Scholar
  23. 23.
    Smith RN, Karmo M, Russell J et al (2007) The variability of the curvature of the labial surface of the maxillary anterior teeth along the facial axis of the clinical crown. Arch Oral Biol 52:1037–1042CrossRefPubMedGoogle Scholar
  24. 24.
    Sousa MVS, Vasconcelos EC, Janson G et al (2012) Accuracy and reproducibility of 3‑dimensional digital model measurements. Am J Orthod Dentofacial Orthop 142:269–273CrossRefPubMedGoogle Scholar
  25. 25.
    Stevens DR, Flores-Mir C, Nebbe B et al (2006) Validity, reliability, and reproducibility of plaster vs digital study models: comparison of peer assessment rating and Bolton analysis and their constituent measurements. Am J Orthod Dentofacial Orthop 129:794–803CrossRefPubMedGoogle Scholar
  26. 26.
    Thiruvenkatachari B, Al-Abdallah M, Akram NC et al (2009) Measuring 3‑dimensional tooth movement with a 3-dimensional surface laser scanner. Am J Orthod Dentofacial Orthop 135:480–485CrossRefPubMedGoogle Scholar
  27. 27.
    Tong H, Enciso R, van Elslande D et al (2012) A new method to measure mesiodistal angulation and faciolingual inclination of each whole tooth with volumetric cone-beam computed tomography images. Am J Orthod Dentofacial Orthop 142:133–143CrossRefPubMedGoogle Scholar
  28. 28.
    Ursi WJS, Almeida RR, Tavano O et al (1990) Assessment of mesiodistal axial inclination through panoramic radiography. J Clin Orthod 24:166–173PubMedGoogle Scholar
  29. 29.
    van Loenen M, Degrieck J, De Pauw G et al (2005) Anterior tooth morphology and its effect on torque. Eur J Orthod 27:258–262CrossRefPubMedGoogle Scholar
  30. 30.
    van Vlijmen OJC, Maal TJJ, Bergé SJ et al (2009) A comparison between two-dimensional and three-dimensional cephalometry on frontal radiographs and on cone beam computed tomography scans of human skulls. Eur J Oral Sci 117:300–305CrossRefPubMedGoogle Scholar
  31. 31.
    Viazis AD (1995) Bioefficient therapy. J Clin Orthod 29:552–568PubMedGoogle Scholar
  32. 32.
    Whetten JL, Williamson PC, Heo G et al (2006) Variations in orthodontic treatment planning decisions of class II patients between virtual 3‑dimensional models and traditional plaster study models. Am J Orthod Dentofacial Orthop 130:485–491CrossRefPubMedGoogle Scholar

Copyright information

© Springer Medizin Verlag GmbH, ein Teil von Springer Nature 2018

Authors and Affiliations

  • Iury Oliveira Castro
    • 1
  • Bruno Frazão Gribel
    • 2
  • Ana Helena Gonçalves de Alencar
    • 3
  • José Valladares-Neto
    • 4
  • Carlos Estrela
    • 4
  1. 1.School of Medicine, Departamento de Ciências EstomatológicasUniversidade Federal de GoiásGoiâniaBrazil
  2. 2.Private practiceBelo HorizonteBrazil
  3. 3.Department of Oral ScienceUniversidade Federal de GoiásGoiâniaBrazil
  4. 4.School of DentistryUniversidade Federal de GoiásGoiâniaBrazil

Personalised recommendations