Predisposing factors to severe external root resorption associated to orthodontic treatment

Gracemia Vasconcelos Picanço,Fabricio Pinelli Valarelli,Rodrigo Hermont Cançado,Paulo Roberto Barroso Picanço,Karina Maria Salvatore de Freitas,Camila Pontes Feijão

doi:10.1590/s2176-94512013000100022

Gracemia Vasconcelos Picanço, Fabricio Pinelli Valarelli + Show 4 more

Open Access

https://doi.org/10.1590/s2176-94512013000100022

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Abstract

The aim of this study was to evaluate predisposing factors among patients who developed moderate or severe external root resorption (Malmgren's grades 3 and 4), on the maxillary incisors, during fixed orthodontic treatment in the permanent dentition. Ninety-nine patients who underwent orthodontic treatment with fixed edgewise appliances were selected. Patients were divided into two groups: G1 - 50 patients with no root resorption or presenting only apical irregularities (Malmgren's grades 0 and 1) at the end of the treatment, with mean initial age of 16.79 years and mean treatment time of 3.21 years; G2 - 49 patients presenting moderate or severe root resorption (Malmgren's grades 3 and 4) at the end of treatment on the maxillary incisors, with mean initial age of 19.92 years and mean treatment time of 3.98 years. Periapical radiographs and lateral cephalograms were evaluated. Factors that could influence the occurrence of severe root resorption were also recorded. Statistical analysis included chi-square tests, Fisher's exact test and independent t tests. The results demonstrated significant difference between the groups for the variables: Extractions, initial degree of root resorption, root length and crown/root ratio at the beginning, and cortical thickness of the alveolar bone. It can be concluded that: Presence of root resorption before the beginning of treatment, extractions, reduced root length, decreased crown/root ratio and thin alveolar bone represent risk factors for severe root resorption in maxillary incisors during orthodontic treatment.

Highlights

The sample consisted of 99 patients from the Paulo Picanço Advanced Orthodontics Center, Fortaleza-CE, who underwent orthodontic treatment with fixed appliance (Edgewise technique) in the permanent dentition, and met the following requirements: Good oral and systemic health, no tooth loss in the region from canine to canine in the maxillary arch, absence of vertical bone loss and periodontal disease, and no prosthesis
Increased age and longer treatment was significantly related to the occurrence of severe root resorption (Table 2)
Treatment time The results showed that a longer treatment is a risk factor to the occurrence of severe root resorption, as the group 1 showed a significantly shorter treatment time compared to group 2 (Table 2)

Summary

Methods

MaterialThe sample consisted of 99 patients from the Paulo Picanço Advanced Orthodontics Center, Fortaleza-CE, who underwent orthodontic treatment with fixed appliance (Edgewise technique) in the permanent dentition, and met the following requirements: Good oral and systemic health, no tooth loss in the region from canine to canine in the maxillary arch, absence of vertical bone loss and periodontal disease, and no prosthesis. Sample division: » Group 1 (Patients who had degree 0 or 1 of root resorption of the maxillary incisors at the end of treatment): 50 patients, 26 without and 24 with extractions (13 first premolars; 8 second premolars and 3 first molars). » Group 2 (patients who had degree 3 or 4 of root resorption in maxillary incisors at the end of treatment): 49 patients, 26 without and 24 with extractions (31 first premolars, 9 second premolars, 2 first molars) The mean age at the beginning of the treatment was 19.92 years and the mean age at the end of treatment was 23.90 years. The periapical radiographs were analyzed as follows: The degree of initial and final, based on the classification proposed by Malmgren: Grade 0 (no resorption), grade 1 (presence of apical irregularities), grade 2 (presence of resorption by 2 mm), grade 3 (presence of resorption between 2 mm and a third of the original length), grade 4 (the presence of root resorption greater than one third of the original length of the root) (Fig 1).[7,8]

Results

Discussion

Conclusion