Giordana Ariane Ribeiro Schwerz Antunes de Melo; Karine Martelli; Karina Maria Salvatore de Freitas; Fabrício Pinelli Valarelli; Rodrigo Hermont Cançado
Abstract
Background: The purpose of the present study was to evaluate the influence of asthma on the degree of apical root resorption in patients treated orthodontically.
Methods: Sample comprised 683 patients treated orthodontically; 240 with asthma and 443 who did not present any kind of respiratory allergy ...
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Background: The purpose of the present study was to evaluate the influence of asthma on the degree of apical root resorption in patients treated orthodontically.
Methods: Sample comprised 683 patients treated orthodontically; 240 with asthma and 443 who did not present any kind of respiratory allergy or asthma. The Levander and Malmgren score was used for the evaluation of the degree of root resorption. This evaluation was performed in the initial and final periapical radiographs of the maxillary and mandibular incisors of all patients in the sample. Then, the sample was divided as follows: Group 1: 614 patients presenting mild or no root resorption with scores 0, 1 and 2, with mean initial age of 14.37 years, final age of 16.44 years and treatment time of 2.07 years; group 2: 69 patients who had moderate to severe root resorption with scores 3 and 4, with mean initial age of 15.09 years, final age of 17.81 years and treatment time of 2.72 years. Results: The results revealed that asthma was not a statistically significant factor for severe root resorption. The group with severe root resorption showed higher initial and final age, and longer treatment time than the group with mild root resorption. In addition, performing extractions is a risk factor for the occurrence of severe root resorption.
Conclusions: Asthma is not a risk factor for the occurrence of severe root resorption after orthodontic treatment.
Giulia Gay; Serena Ravera; Tommaso Castroflorio; Francesco Garino; Giovanni Cugliari; Andrea Deregibus
Abstract
Background: Existing literature indicates that orthodontics patients are more likely to have severe apical root shortening, interesting mostly maxillary, followed by mandibular incisors.
Objectives: The aim of the present study was to investigate the incidence and severity of root resorption (RR) in ...
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Background: Existing literature indicates that orthodontics patients are more likely to have severe apical root shortening, interesting mostly maxillary, followed by mandibular incisors.
Objectives: The aim of the present study was to investigate the incidence and severity of root resorption (RR) in mandibular incisors of adult patients treated with aligners.
Methods: The study group consisted of 71 adult healthy patients (mean age 32.8 ± 12.7) treated with aligners (Invisalign®, Align Technologies, San Jose, CA, USA) for the intrusion of the lower incisors. Root and crown lengths of a total of 279 lower incisors were measured in panoramic radiographs at the beginning (T0) and at the end (T1) of aligner therapy. Individual root-crown-ratio (RCR) of each tooth and therefore the relative changes of RCR (rRCR) were determined. Results: 44% of the 279 measured teeth presented a reduction of the pre-treatment root length. A reduction in percentage of > 0% up to 10% was found in 26.76% (n = 76), a distinct reduction of > 10% up to 20% in 12.32% (n = 35) of the sample. 4.58% (n = 13) of the teeth were affected by a clinically relevant reduction (> 20%).
Conclusions: Orthodontic treatment with Invisalign® aligners could led to RR in cases in which intrusion of the lower incisors is planned. However, the incidence of RR is comparable to data described in case of application of light forces with fixed appliances, and considerably lower than what has been described for traditional comprehensive orthodontic treatments.
Seyed Mohammadreza Safavi; Mehdi Ravadgar; Fatemeh Mashhadiabbas; D. Sharifi; Alireza Akbarzadeh Baghban
Abstract
Background and aims: To evaluate the frequency of ankylosis, loss of pulp vitality and external root resorption after intentional root contact with mini-screw.Methods: Sixty maxillary and mandibular second, third, and fourth premolars teeth of five mature beagle dogs were randomly assigned into three ...
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Background and aims: To evaluate the frequency of ankylosis, loss of pulp vitality and external root resorption after intentional root contact with mini-screw.Methods: Sixty maxillary and mandibular second, third, and fourth premolars teeth of five mature beagle dogs were randomly assigned into three experimental groups. Premolars teeth at group I, received a mini-screw (6-mm length, 1.5mm diameter, self drilling) which was removed immediately after contact with the root. Group II consisted of teeth that received mini-screw and the screw left in situ for 15 weeks. In group III once contact was made with mini-screw, the teeth were shifted away from the screw with brackets and Titanium closed coil spring tightened to another bonded orthodontic brackets on the neighbor teeth. Group IV was the control group. The specimens were decalcified, stained and evaluated histologically to determine the presence/absence of root resorption, ankylosis and tooth vitality.Results: There were no signs of ankylosis, root resorption, moderate to severe inflammation or necrosis within the pulp in any experimental group.Conclusions: Ankylosis, pulp necrosis and sever root resorption are not common clinical outcomes when mini-screw contacts the root. Repair after contact with mini-screw depends on the severity of invasion. More severe invasion needs further time necessary for repair.
Massoud Seifi; Roya Hamedi; Maryam Nazirii
Abstract
Background and aim: Orthodontic tooth movement requires remodeling of periodontal tissues, especially alveolar bone. A major objective of investigators is to achieve maximum tooth movement with minimal root damage. The aim of this study is to determine if the rate and amount of orthodontic tooth movement ...
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Background and aim: Orthodontic tooth movement requires remodeling of periodontal tissues, especially alveolar bone. A major objective of investigators is to achieve maximum tooth movement with minimal root damage. The aim of this study is to determine if the rate and amount of orthodontic tooth movement in a sample of rats could be enhanced by the injection of a vitamin D metabolite and Prostaglandin E2.Materials and Methods: Thirty-Two male Wistar rats were randomly divided into 4 groups of eight rats each: 1- 1.5 IU/ml vitamin D was injected into the thigh muscle after installation the orthodontic appliance in first group (Vit D group)
2- 0.1 ml of 1 mg/ml PGE2 was injected submucosally in the second group (PGE2 group).
3- In the third group, 1.5 IU/ml vitamin D and 0.1 ml of 1 mg/ml PGE2 was injected submucosally (Vit D+ PGE2).
4- Distilled water (0.1 ml) was used in control group .In order to calculate the tooth movement; the distance between the upper right first and second molars was measured.Results: All groups have a significant difference with control group (p<0.05). The most mean OTM was observed in the Vit D+PGE2 group (Mean = 0.702± 0.04897mm) that was significantly higher than the Vit D, PGE2 and control groups (P< 0.05). A significant difference (P< 0.05) in root resorption was observed between the PGE2 (0.0192 ±0.000675 mm2) and the other groups.Conclusion: In order to achieve a decrease in root resorption and an increase in OTM, the combination Vit D+PGE2 is useful and there is a synergism effect with Vit D and PGE2.
Mehdi Hassanpour; Amirhossein Mirhashemi; Atefe Saffarshahroudi; Allahyar Geramy
Abstract
Cone beam CT (CBCT) has become an increasingly important source of three dimensional (3D) volumetric data in clinical orthodontics since its introduction into dentistry in 1998. The purpose of this manuscript is to highlight the current understanding of, and evidence for, the clinical use of CBCT in ...
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Cone beam CT (CBCT) has become an increasingly important source of three dimensional (3D) volumetric data in clinical orthodontics since its introduction into dentistry in 1998. The purpose of this manuscript is to highlight the current understanding of, and evidence for, the clinical use of CBCT in orthodontics, and to review the findings to answer clinically relevant questions. It has therefore been recommended that CBCT be used in selected cases in which conventional radiography cannot supply satisfactory diagnostic information; which include cleft palate patients, assessment of unerupted tooth position, supernumerary teeth, identification of root resorption and planning orthognathic surgery. The need to use in other types of cases should be made on a case-by-case basis following an assessment of benefits vs risks of scanning in these situations.
Esfandiar Akhavan Niaki; Javad Chalipa; Ahmad Reza Dehpour; M Khalili; Arezoo Ghahari
Abstract
Aim: The appearance of osteoclasts is the first step in orthodontic tooth movement. During orthodontic force application, the periodontal ligament (PDL) undergoes hyalinization. This tissue damage prevents the tooth from moving until the adjacent bone and necrotic tissue are removed by osteoclasts. There ...
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Aim: The appearance of osteoclasts is the first step in orthodontic tooth movement. During orthodontic force application, the periodontal ligament (PDL) undergoes hyalinization. This tissue damage prevents the tooth from moving until the adjacent bone and necrotic tissue are removed by osteoclasts. There is a range of forces that produce the maximum rate of tooth movement. The purpose of this study was to compare the effect of different orthodontic forces on osteoclast numbers.Materials and Methods: Forty rats were randomly divided to 4 experimental groups. Appliance exerted 25gr in light, 40gr in moderate and 60gr in heavy group. There was not any appliance in control group. Animals were sacrified after 14 days and tissue samples were prepared. The mesial and distal surfaces of first upper molar and adjacent alveolar bone were studied. Osteoclast numbers, cementoclast numbers, root length, root resorption, depth and length of resorptive cavities, PDL. width in coronal-middle-apical, apical and coronal inflammation, bone resorption, necrotic bone and tooth movement were evaluated. Mesial and distal surfaces were also compared.Results: In menial osteoclast numbers, depth of resorptive cavities, bone resorption, necrotic bone, PDL width and in distal apical inflammation, bone resorption, necrotic bone and PDL width were significant. Tooth movement was significantly different between all groups. (P<0.05)Conclusion: This data suggest that osteoclasts numbers are increased when force is increased. The magnitude of the orthodontic force is believed to be an important factor, not only for the magnitude of the tooth movement but also for any tissue damage.
