Download ROOT RESORPTION IN ORTHODONTICS – GENETIC

ROOT RESORPTION IN ORTHODONTICS –
GENETIC SUSCEPTIBILITY?
Maria João Ponces *, Paula Vaz **, Fred Pinheiro ***, Inês Côrte-Real ****, Purificação Tavares *****
• Specialist in Orthodontics by Portuguese Dental Association, Assistant Professor of Orthodontics in the Faculty of Dental Medicine of Porto University (FMDUP); ** Dentist, Assistant Professor of Medical Genetics I, II and Orofacial Genetics in the
FMDUP; *** Dentist, Assistant of Medical Genetics I, II and Orofacial Genetics in the FMDUP; **** Dentist, PhD student of FMDUP; ***** Medical Geneticist, Professor of Medical Genetics I, II and Orofacial Genetics in the FMDUP.
Faculty of Dental Medicine. University of Oporto. Rua Manuel Dr. Manuel Pereira da Silva 4200-393 Porto. Portugal. Email: [email protected]
External root resorption (ERR) is a condition that can be perceived in association with orthodontic treatment (Hartsfield Jr et al., 2004; Al-Qawasmi et al., 2006; Abass et al.,
2008; Lages et al., 2009). The etiology of root resorption is complex and includes several factors, such as individual susceptibility, familial association, ethnics, allergies and
asthma, magnitude and direction of maxillary incisors displacement and root morphology (Apajalahti & Peltola, 2007; Marques et al., 2010; Krishnan, 2005; Abass et al., 2008;
Lages et al., 2009). Some inflammatory mediators, controlled by specific genes, have been associated with bone resorption and in the recruitment of osteoclasts during
orthodontic movement (Abass et al., 2008; Lages et al., 2009; Proff & Römer, 2009). Particularly the relation between polymorphisms in the IL1B gene and ERR, during
orthodontic treatment, has been described in the literature (Al-Qawasmi et al., 2003; Hartsfield Jr et al., 2004; Hartsfield Jr, 2009; Lages et al., 2009).
The aim of this paper is to present a case of a male orthodontic patient, caucasian, 15 years old, with a positive family history of generalized ERR associated to orthodontic
treatment. In addiction, the authors consider relevant to present and simultaneously clarify the role of the genetic susceptibility, in the pathogenesis of the ERR, in this
particular case and in possible similar ones. It was performed a literature review on PUBMED with the key words dental orthodontics resorption genetics , 12 articles were obtained and 5 of them were included. There
were also associated with the theme 6 more articles, from the list of related articles. The search was limited to the last 10 years and to the English, French and Spanish idioms. A caucasian male patient, with 15 years and 1 month of age went to an orthodontic appointment in order to start treatment (Figure 1). As there was positive familial history of
ERR after orthodontic rehabilitation and external etiological factors associated with the orthodontic treatment were not identified, it was hypothesized a possible individual
genetic susceptibility. The positive familial history was related to the sister of the proband (Figure 2), a female caucasian patient (Figure 3), that performed orthodontic
treatment and developed a ERR, as observed in the panoramic radiograph sequence (Figures 4, 5, 6), as well as in the retro-alveolar radiograph (Figure 7). In order to try to
clarify this issue, it was decided to perform a genetic test, for the detection of a single polymorphism on the gene IL1B (position +3953)(TGP, CGC Clinical Genetics Center,
Portugal)(Figure 8), which revealed the presence of the allele 1 on the IL1B gene – a negative result to the TGP but a positive result to the development of ERR. Certain studies
pointed that homozygous patients for allele 1 of IL1B gene had 5.6 times higher risk of developing an ERR greater than 2 mm than those who were not homozygous for the
same allele (Al-Qawasmi et al., 2003-a). According to this and other investigations, the presence of the allele 1 of the IL1B gene decreases the production of interleukin-1 βeta,
which may be responsible for the lower cortical bone resorption in periodontal ligament surface, resulting on an increased pressure on root which, in turn, promotes necrosis
and finally root resorption (Figure 9)(Al-Qawasmi et al., 2003-a; Al-Qawasmi et al., 2004).
Figure 8 – Position of the IL1B gene polymorphism assayed by
the genetic test (TGP, CGC Clinical Genetics Center, Portugal).
Source: Vaz P. PhD Tesis. FMDUP, 2010.
IL1B /
Allele 1
Decrease
Production/
Absence
Lower cortical bone
resorption
(periodontal ligament
surface)
Increase pressure on
root
Necrosis
Root
Resorption
Figure 1 – Photographs and panoramic radiograph of the
male patient and proband.
Figure 2 – Heredogram with
affected sister and proband.
Figure 3 – Sister’s photographs of the proband.
Figure 9 – Diagram of the genetic pathway for susceptibility to
ERR in an orthodontic treatment.
Figures 4, 5, 6 – Panoramic radiograph sequence of the affected sister (initial and controls - years 2001, 2002 and 2005).
Figure 7 – Retro-alveolar
radiograph of the
affected sister (year 2006).
The identification of individuals with increased susceptibility to ERR should be considered during the orthodontic treatment planning to allow the required adjustments, in
terms of magnitude of the employed force and also in respect to the duration of treatment. The recognition of the genetic role in this pathologic condition is important for
orthodontic treatment considerations in particular in regard to the duration and the complexity of treatment being settled to patients with this possible risk.
-  Abass SK, Hartsfield JK Jr, Al-Qawasmi RA, Everett ET, Foroud TM, Roberts WE. Inheritance of susceptibility to root resorption associated with orthodontic force in mice. Am J Orthod Dentofacial Orthop. 2008;134(6):742-750.
- Al-Qawasmi RA, Hartsfield JK Jr, Everett ET, Flury L, Liu L, Foroud TM, Macri JV, Roberts WE. Genetic predisposition to external apical root resorption. Am J Orthod Dentofacial Orthop. 2003;123(3):242-252.
-  Al-Qawasmi RA, Hartsfield JK, Hartsfield JK Jr, Everett ET, Weaver MR, Foroud TM, Roberts WE. Root resorption associated with orthodontic force in IL-1Beta knockout mouse. J Musculoskelet Neuronal Interact. 2004;4(4):383-385.
-  Al-Qawasmi RA, Hartsfield JK Jr, Everett ET, Weaver MR, Foroud TM, Faust DM, Roberts WE. Root resorption associated with orthodontic force in inbred mice: genetic contributions. EurJ Orthod. 2006;28(1):13-19.
-  Apajalahti S, Peltola JS. Apical root resorption after orthodontic treatment -- a retrospective study. Eur J Orthod. 2007;29(4):408-12.
-  Hartsfield JK Jr, Everett ET, Al-Qawasmi RA. Genetic factors in external apical root resorption and Orthodontic Treatment. Crit Rev Oral Biol Med. 2004;15(2):115-122.
-  Hartsfield JK Jr. Pathways in external apical root resorption associated with orthodontia. Orthod Craniofac Res. 2009;12(3):236-42
-  Krishnan V. Critical issues concerning root resorption: a contemporary review. World J Orthod. 2005;6(1):30-40.
-  Lages EMB, Drummond AF, Pretti H, Costa FO, Lages EJ, Gontijo AI, Miranda CotaL O, Brito RB Jr. Association of functional gene polymorphism IL-1beta in patients with external apical root resorption. Am J Orthod Dentofacial Orthop. 2009;136(4):542-546.
-  Marques LS, Ramos-Jorge ML, Rey AC, Armond MC, Ruellas AC. Severe root resorption in orthodontic patients treated with the edgewise method: prevalence and predictive factors. Am J Orthod Dentofacial Orthop. 2010;137(3):384-8.
-  Proff P, Römer P. The molecular mechanism behind bone remodelling: a review. Clin Oral Investig. 2009;13(4):355-362.