Showing 17 results for Orthodontic
S. Khedmat ,
Volume 18, Issue 1 (3-2005)
Abstract
The purpose of this article was reviewing the literature related to the mutual effects of endodontics and orthodontics on each other providing documented information that can be used by dentists in clinical practice. The effect of orthodontic treatment on the dental pulp and its role in root resorption, the influence of previous trauma to the tooth and endodontic treatment in orthodontic tooth movements and root resorption, recommendations regarding endodontic treatment during orthodontic tooth movement and the role of the orthodontic forces in provision and outcome of endodontic treatment are being discussed. The effect of the orthodontic tooth movement on the pulp is focused primarily on the neurovascular system which can cause degenerative and/or inflammatory responses in the dental pulp. Although, most of these changes are considered reversible, it seems that teeth with complete apical foramen and teeth subjected to previous insults, such as trauma, caries, restorations and periodontal diseases are more susceptible to pulpal irreversible changes. Teeth with root canal treatment that are well cleaned shaped, and three- dimensionally obturated, exhibit less propensity to apical root resorption during orthodontic tooth movement. This outcome depends on the absence of microleakage for bacterial ingress. A traumatized tooth can be moved orthodontically with minimal risk of resorption, provided that the pulp has not been severely injured (infection or necrosis). If there is evidence of pulpal demise, appropriate endodontic treatment is necessary prior to orthodontic treatment .If a previously traumatized tooth exhibits resorption, there is a greater chance that orthodontic tooth movement will enhance the resorptive process. If a tooth has been severely traumatized (intrusion, avulsion) there would be a greater incidence of resorption with tooth movement. It is recommended that teeth requiring root canal treatment during orthodontic movement be initially cleaned and shaped followed by the interim placement of calcium hydroxide. Final canal obturation with gutta-percha should be accomplished upon the completion of orthodontic treatment. Endodontically treated teeth can be moved orthodontically similar to teeth with vital pulps. In case of endodontic procedures like apexification, there may be no need to delay the orthodontic treatment.
H. Ravanmehr , Sm. Seyed Javadein ,
Volume 18, Issue 4 (1-2006)
Abstract
Background and Aim: External apical root resorption is a common iatrogenic consequence of orthodontic treatment. Much controversy exists in the literature about changes in root lengths at post treatment periods. Although many practitioners believe that resorption becomes stable after active treatment, quantitative data are scarce. The purpose of this study was to determine quantitative changes in root lengths of maxillary incisors during fixed orthodontic post treatment period, and to assess if it is influenced by gender and factors related to active treatment.
Materials and Methods: This was a case cross over study, performed on 80 patients (52 females and 28 males) aged between 13 and 22 years. At debonding stage and beginning of retention phase of fixed orthodontic treatment, Hawley type retainer was fabricated for maxillary arch. Periapical radiographs of maxillary incisors using standard parallel technique were obtained immediately after debonding, and 3 and 7 months later. Crown and root lengths of maxillary incisors were measured using computer program. Changes in root lengths were calculated considering correction factors. Also associations between some factors and the change in root lengths during post treatment periods were assessed. These included gender, type of treatment plan (non extraction/extraction), technique (standard edgewise/straight-wire edgewise) and duration of active treatment (less than 2 years/2 years and more). T-test and 4-way ANOVA were used for statistical analysis with P0.05 as the limit of significance.
Results: No significant relation was found between apical root resorption of maxillary central incisors and time elapsed after treatment. Significant relation was observed between apical root resorption of maxillary lateral incisors and the length of post treatment period. No significant relation was found between root length changes of maxillary incisors during post treatment period and gender, type of treatment plan, technique, and the length of active treatment period (P 0.05).
Conclusion: Considering the general process of root length reduction in maxillary lateral incisors during post treatment period, establishment of preventive measures is emphasized.
Smr. Safavi , M. Farahani , S. Khoramian Tusi , So. Dianat , Ar. Akbarzade ,
Volume 20, Issue 2 (5-2007)
Abstract
Background and Aim: In recent years, different substances have been considered in gingival cervical fluid (GCF) as diagnostic markers due to the evaluation of biologic events and biochemical process related to bone turnover during orthodontic movements. IL-6 concentration increases in GCF during the first week after force loading. The aim of this study was to investigate the levels of IL-6 in GCF during orthodontic movements.
Materials and Methods: Fourteen orthodontic patients (9 females and 5 males, mean age 15.1±2.5 years) with Cl I malocclusion needing first bicuspid extraction participated in this clinical trial. In each patient one maxillary canine was distalized (DC) with a NiTi push coil spring. The contra-lateral canine (CC) was included in the orthodontic appliance but was not subjected to the orthodontic force and one of the mandibular canines was used as control with no orthodontic appliance (Antagonist canine: AC). The concentration of IL-6 was evaluated at the baseline and 14th and 28th days after intervention. GCF was taken with periopapers from both mesial and distal sides of tooth before appliance activation, on the 14th and 28th days. Concentration of IL-6 in DC, CC, and AC detected by ELISA reader was compared by repeated measure ANOVA and LSD multiple comparison, P<0.05 was considered statistically significant.
Results: Although the inflammatory gingival indices increased in both DC and CC teeth but it was not significant. The amount of IL-6 in GCF increased on day 14th in DC teeth in comparison with AC and CC teeth. In addition, the concentration of IL-6 in DC teeth was significantly greater than the 1st and 28th days. The maximum concentration of IL-6 was detected in both pressure and tension sides of DCs at T14. At T28, although the IL-6 levels were significantly higher than baseline levels but, it was significantly less than T14.
Conclusion: The results of this study support the hypothesis that mechanical stimuli cause an inflammatory reaction within the periodontal tissues.
F. Amini, F. Soboti, M. Shariati, Z. Zoshad Haghighi,
Volume 24, Issue 2 (4-2011)
Abstract
Background and Aims: Considering the application of recycled metallic brackets in orthodontic treatments and probably more resultant metal ion release, which can cause cytotoxic side effects, this study was set up to assess the effect of recycling process of orthodontic brackets on metal ion release.
Materials and Methods: In this experimental study, 80 Discovery direct bond brackets (Dentarum, Germany) were divided into 2 groups, new and recycled brackets (n = 40), then each group was divided into two subgroups (one-week and 6-months subgroups) (n=20). The specimens were maintained in buffered solution of NaNHNo3 (pH=7) at 37°C in an incubator. After periods of one week and 6 months immersion, 0.5 mL of each solution was analyzed by spectrophotometry for the quantity of released Nickel (Ni), Chromium (Cr), and Cobalt (Co) ions. The data were analyzed using two way ANOVA analysis.
Results: After one week, the quantity of Ni, Cr, and Co ions released from new brackets were 0.65, 1.4, and 0.75 (ppb), respectively. The values for recycled brackets were 142, 2.61, and, 1.43 (ppb). These findings indicated significant difference between two groups (P<0.001). After six months, the quantity of Ni, Cr, and Co ions released from new brackets were 1200, 3.4, and 2.4 (ppb) and from recycled brackets were 2330, 6.9, and 10.8 (ppb), which showed significant difference between two groups (P<0.001).
Conclusion: Application of recycled brackets in long fixed orthodontic treatments can lead to metal ion release, specifically Nickel. Thus, the use of recycled brackets in long orthodontic treatments is not recommended.
F. Mojtahedzadeh, S. Alizadeh,
Volume 24, Issue 2 (4-2011)
Abstract
Background and Aims: Cephalometric measurements cannot be performed for screening purposes, therefore orthodontists usually have to use either photographic or anthropometric measurements in such occasions. Finding a valid and reliable alternative could be of great value. The purpose of this study was to evaluate the correlation between McNamara's cephalometric unit difference and a proposed soft tissue equivalent.
Materials and Methods: An anthropometric ruler was redesigned and used in this study. Soft tissue measurements were performed on 36 randomly selected specimens by two investigators. The soft tissue measurements included external auditory meatus to subnasale (Ext-Sn), external auditory meatus to soft tissue pogonion (Ext-Pog), and the difference between them (UDMA´). These measurements were considered as equivalents to cephalometric indices in McNamara's anteroposterior measurements, including maxillary (Co-A) and mandibular (Co-Gn) unit length and their difference (UDMA), respectively.
Results: All soft tissue variables had an intra-class correlation coefficient (ICC) above 0.90. There was a high and significant correlation between cephalometric and anthropometric measurements (P<0.01). The ICC between (Ext-Sn) and (Co-A) was 0.890, 0.869 between (Ext-Pog) and (Co-Gn), and 0.819 between UDMA´ and UDMA.
Conclusion: The proposed anthropometric method showed a good correlation with cephalometric equivalents and the results show that this method could be used for screening purposes, especially when a low-cost, non-invasive method is required. However it cannot be considered as a substitute for cephalometry in diagnostic and treatment purposes.
Mh. Hosseini, M. Mahmoodzadeh Darbandi, A. Kamali,
Volume 24, Issue 3 (6-2011)
Abstract
Background and Aims: Lasers with different characteristics have been used to stimulate orthodontic tooth movement. Considering the contradictory findings in this regard, this study was designed to assess the effect of low level laser therapy (LLLT) on the rate of orthodontic tooth movement.
Materials and Methods: In this randomized clinical trial study, 12 patients (4 boys and 8 girls average age:16.9 ± 3.4) with extracted upper first premolars and required canine retraction into extraction site were included. While in both sides canines were retracted by NiTi coil spring, one side was exposed to GaAlAs laser (890 nm). LLLT was done (on the buccal and palatal mucosa by slow movement of probe) at the beginning of the first month. Impression and cast fabrication performed at the beginning of retraction, one and two months later. The amount of retraction on the cast was measured with the aid of a reference plaque fabricated on the rogae using a digital caliper. Data were analyzed using paired sample T-test and one-sample Kolmogorov-Simirnov test.
Results: There was no significant difference in the amounts of canine movement between laser exposed and control sides (P>0.05).
Conclusion: The energy dose of laser used in this study (72 J per each tooth) was not appropriate for increasing dental movement.
Imaneh Asgari, Arezo Ebn Ahmady, Mohammad Hossein Khoshnevisan, Faezeh Eslamipour,
Volume 25, Issue 2 (4-2012)
Abstract
Background and Aims: Normative need assessments should be substituted or integrated by patient-based outcome measures regarding their shortages in health-oriented approach . This study aimed to assess and compare the ability of an index of oral health-related quality of life measured by Child Oral Health Impact Profile (COHIP) questionnaire and the Aesthetic Component of Index of Orthodontic Treatment Need (AC-IOTN) to identify the normative need to orthodontic treatment using Dental Health Component-IOTN in a sample of the Iranian adolescents.
Materials and Methods: Target population of this cross-sectional analytic study was 597 of the 13 to 18 year-old schoolchildren enrolled in middle and high schools of the city of Isfahan, Iran. They completed the COHIP questionnaire and then were examined by two calibrated trained dentists (agreement coefficient:0.9) to record the DHC grading. The students scored their AC in according to the images of the scale. The association between subjective indicators and clinically defined need were evaluated by the correlation analysis and the statistics for the diagnostic validity of tests.
Results: Of 568 examined students, 16.7% and 2.1% had definite need according to DHC and AC criteria, respectively. 10% of orthodontic patients had perceived distinct impact on their quality of life. The significant association (P=0.001) between the severity of malocclusion and quality of life was at moderate level by AC (R=0.37), but it was not convincing enough by DHC (R=0.16). The specificity of AC to detect the healthy ones showed to be excellent but its low sensitivity disabled the recognition of patients, precisely.
Conclusion: The considered patient-based indices did not meet the competencies to define the orthodontic need in the adolescents, but it could be employed to identify the persons with impaired quality of life and it would probably benefit the process of prioritization.
Sina Haghanifar, Valiollah Arash, Farhad Soboti, Nasim Jafari,
Volume 25, Issue 2 (4-2012)
Abstract
Background and Aims: Apical root resorption is an adverse side effect of fixed orthodontic treatment which cannot be repaired. The aim of this study was to use panoramic radiographs to compare the root resorption before and after the orthodontic treatment with standard edgewise .018 appliance.
Materials and Methods: The before and after treatment panoramic views of sixty-three patients needed fixed orthodontic treatment included 1520 teeth were categorized into 3 Grades (G0: without resorption, G1: mild resorption with blunt roots or ≤ 1/4 of root length, G2: moderate to severe resorption or > 1/4 to 1/2 of root length. Relationship between root resorption and sex and treatment duration was analyzed with Mann-whitney and Spearman's correlation coefficient, respectively.
Results: The findings showed that 345 teeth were categorized as Grade 1. Grade 2 of root resorption was not found in this study. The highest amount of root resorption was recorded for the mandibular lateral incisor. In both gender, the root resorption of the mandible was more than that of the maxilla. The males showed significantly higher rate of resorption than the females (P<0.05). Root resorption was not significantly related to the treatment duration and the side of the jaws (P>0.05).
Conclusion: The mandible and male patients showed higher amount of root resorption. In addition, root resorption was not related to the treatment duration and the side of the jaws.
Sahar Ghodsi Bushehri, Farzaneh Khajeh, Somayeh Heidari, Shahla Momeni Danaei,
Volume 26, Issue 2 (5-2013)
Abstract
Background and Aims: Skeletal class III malocclusions are considered as one of the most complex and difficult orthodontic problems to diagnose and treat. Facial appearance and occlusion problems make the patients to seek treatment as soon as possible. The purpose of this study was to evaluate the outcomes of early treatment with facemask compared to the patients who had no treatment.
Materials and Methods: For this retrospective study, 38 growing patients (mean age, 8.5 years old) with class III dentoskeletal malocclusion were divided into 2 groups. 23 patients were treated with facemask and 15 patients who did not receive any treatment were assigned as control group. Lateral cephalograms were taken before and after treatment and dentoskeletal changes were estimated. Data were analyzed using Wilcoxon signed ranks test.
Results: The results revealed statistically significant forward displacement of maxillary bone and upper incisors (P<0.001), and downward-backward rotation of mandible in facemask group (P<0.001). Increased lower facial height was seen in both treatment and untreated groups. However, in untreated group some measurements revealed forward displacement of maxillary complex as well.
Conclusion: It seems that in class III patients treating with facemask is a better choice than ChinCap and decision making for early treatment in class III patients should be considered seriously. Moreover, specific attention to the type of patient’s skeletal discrepancy is necessary. In class III patients, facemask might be a better option than other appliances.
Hooman Zarif Najafi, Morteza Oshagh, Parisa Salehi, Hamid Keshavarz,
Volume 27, Issue 2 (6-2014)
Abstract
Background and Aims: Orthodontic patients’ cooperation is a determining factor in treatment outcomes. The aim of this study was to evaluate the relationship between patient cooperation during orthodontic treatment with variables such as age, sex, life setting, treatment duration and functional and social discomfort experienced.
Materials and Methods: Specimens were consisted of 100 orthodontic patients (36 males and 64 females) between 13-35 years old (average age: 22.57±1.69 years). Patients’ demographic traits, treatment duration and
functional-social discomfort by the orthodontic treatment were evaluated using a questionnaire answered by the patients or their parents. The degree of patient cooperation was assessed by the modified cooperation questionnaire (Orthodontic Patient Cooperation Scale [OPCS]) which was completed by an orthodontist. Data were analyzed using One-way ANOVA, T-test, intraclass correlation coefficient and Pearson Correlation.
Results: No significant difference was found between the cooperation of male and female patients (P=0.867) and also between the cooperation of the patients who lived in the urban and rural setting (P=0.613). Treatment duration and compliance showed a low negative correlation which was not statistically significant (r=-0.155, P=0.127). Functional-social discomfort and compliance showed a low negative correlation which was not statistically significant (r=-0.118, P=0.244). No significant correlations were found between the compliance and age (r=0.002, P=0.988) and also the treatment duration and functional-social discomfort experienced
(r=0.164, P=0.105).
Conclusion: Patient compliance appears to be a complex issue that cannot easily be predicted only by factors such as age, gender, life setting, treatment duration and functional-social discomfort experienced.
Mirhashemi Amirhossein , Geramy Allahyar , Sodagar Ahmad , Baghaeian Pedram ,
Volume 28, Issue 1 (5-2015)
Abstract
The aim of this review article was to define the mechanism of action and effects of commonly used medications on the tissue remodeling and Orthodontic Tooth Movement (OTM). A review on the effects of medications and dietary supplements on the rate of experimental tooth movement was performed using Cochrane library, Embase and medline (1980-2013). 63 articles were included in this review. 34 of them were related to the effects of hormones and analgesics, were evaluated in this article but their interpretation was hindered by the variability in experimental design, magnitude of force applied during tooth movement and medication regimens. Non Steroidal Anti-Inflammatory Drugs (NSAIDs) reduced the rate of tooth movement while non-NSAIDs such as acetaminophen had no effect on the rate of OTM. Corticosteroids, parathyroid hormone and thyroxin increased the rate of tooth movement. Sturgeons might slow OTM, but experimental studies are lacking. Medications might have an important influence on the rate of tooth movement and information on their consumption is necessary to adequately discuss treatment planning with patients.
Amirhossein Mirhashemi, Allahyar Geramy, Ahmad Sodagar, Pedram Baghaeian, Yasamin Jalali,
Volume 28, Issue 2 (7-2015)
Abstract
Molecules produced in various diseased tissues or drugs and nutrients consumed regularly by patients, can reach the mechanically stressed paradental tissues through the circulation and interact with local target cells. The combined effect of mechanical forces and one or more of these agents may be inhibitory, additive or synergistic. The aim of this review was to outline the mechanisms of action and effects of some commonly used drugs on tissue remodeling and Orthodontic Tooth Movement (OTM). A review on the effects of medications and dietary supplements on the rate of experimental tooth movement was performed using Cochrane library, Embase and Medline (1980-2013). 63 articles were included in the review. 34 of them related to the effects of hormones and analgesics were evaluated in the first part of this review. The rest of them (29 articles) were evaluated in the current review, but their interpretation was hindered by the variability in experimental design, magnitude of force applied during tooth movement and medication regimens. Vitamin D3 might enhance the pace of tooth movement, but dietary calcium and fluorides appear to reduce the rate of OTM. Bisphosphonates (BPNs) are considered to have marked inhibitory effects on the rate of tooth movement. Nicotine and nitric oxide might effectively increase the speed of OTM. All drugs reviewed had therapeutic effects, as well as side effects, that may influence the cells targeted by orthodontic forces. Therefore, it is imperative that the orthodontist pays close attention to the drug consumption history of each and every patient, before and during the course of orthodontic treatment. When the use of drugs is revealed, their effects and side effects on tissue systems should be explored to determine their potential influence on the outcome of mechanotherapy.
Faramarz Mojtahedzade, Neda Moslemi, Ahmad Sodagar, Gita Kiaee, Bita ,
Volume 30, Issue 1 (6-2017)
Abstract
Background and Aims: There is an increased risk of periodontal diseases in patients undergoing fixed orthodontic treatment. Chlorhexidine (CHX) is frequently used to promote oral hygiene; however, it is associated with several complications. Herbal mouthwashes can be used as the substitute without having similar complications. The aim the present study was to compare the effects of herbal mouthwashes (Matrica and Persica) with CHX 0.2% on the periodontal parameters of patients under fixed orthodontic treatment.
Materials and Methods: In a double-blind randomized clinical trial, 84 patients under fix orthodontic treatment were selected. After receiving oral hygiene instruction, the patients were randomly assigned to four groups (group 1: Matrica, group 2: Persica, group 3: CHX 0.02%, group 4: normal saline). Dental plaque scores (PI), gingival inflammation (GI) and papillary bleeding (PBI) indices were measured at the beginning, 1 week after receiving oral hygiene instructions and 30 days after mouthwash consumption. The scores of the periodontal indices were statistically analyzed by Kruskal Wallis, ANOVA the paired Mann-whitney U test and Tukey test.
Results: All of the indices were significantly reduced in study groups (except for the control). Matrica and Persica mouthwashes were similarly effective in improving the periodontal parameters. Their efficacy in decreasing the PBI scores was significantly higher than CHX 0.2% (P<0.01).
Conclusion: Application of the two herbal mouthwashes was effective in improving the periodontal parameters in patients undergoing fixed orthodontic treatment.
Behrad Tanbakuchi, Abolghasem Bahador,
Volume 31, Issue 2 (9-2018)
Abstract
Background and Aims: The purpose of this study was to investigate the application of nanoparticles in orthodontics.
Materials and Methods: This study was conducted using a review method by searching Scopous, Google Scholar and Web of science. Key words (Nano silver, Nano ZnO, Nano Chitosan, Nano Curcumin and Nanoparticles) were used. These searches were limited to the English ariticles after the year 2010.
Conclusion: According to the published studies, silver nanoparticles, curcumin, titanium oxide, chitosan, zinc oxide, quaternary ammonium derivatives exhibit appropriate antibacterial properties. Further studies are recommended to investigate the effect of each of these nanoparticles on the bond strength. In order to reduce the decay, there is lack of evidences regarding the addition of ACP nanoparticles and nanoparticles of calcium- phosphate and fluoride. Therefore, further studies are recommended. Studies have shown that the addition of zinc oxide nanoparticles to orthodontic wires could reduce the friction between the wire and the bracket. While, adding titanium oxide nanoparticles to bracket increased the friction. Although, evidences in this regard are inadequate but it seems that nanoparticulates are less toxic than conventional materials.aa
Seyyed Amirhossein Mirhashemi, Sahar Jahangiri, Mina Mahdavi Moghaddam, Rashin Bahrami,
Volume 32, Issue 4 (1-2020)
Abstract
Background and Aims: All metal components of orthodontic appliances are somewhat corroded in the oral environment due to some changes in chemical, mechanical, thermal, microbiological and enzymatic factors which facilitates ion release. Ionic release can result in a discoloration of the surrounding soft tissue or allergic reactions in sensitive patients or even local pain in the area. In general, ions can cause toxic and biological side effects if their values reach the threshold, so the release of ions from the metal components of orthodontic appliances is important to us. The aim of this review article to determine the rate of orthodontic appliances ion release in different solutions.
Materials and Methods: A review of the literature was carried out in Pubmed, Google Scholare and Web of science database using selected key words (Saliva/ Titanium/Normal Saline/ Ion release Orthodontic appliance/Mouth wash/ Nickel/ Chromium). These searches were limited to the articles published from 2005 to 2018. According to the inclusion and exclusion criteria, 25 articles were obtained.
Results: Because of conflicts in the reported results, it was necessary to synchronize the measurement methods and also to use artificial saliva medium with normal pH as a control to achieve better systematic comparison.
Conclusion: There was significant differences in the ion release between mouthwashes. In all studies, the effect of pH and acidity has been shown to increase the release of these ions. In addition, stainless steel (SS) instruments had the least biocompatibility among all types of alloys evaluated.
Vahid Nemati, Reza Shrgi, Nastaran Mansoureiyeh,
Volume 35, Issue 0 (5-2022)
Abstract
Background and Aims: Malocclusion in orthodontics is one of the dental and jaw abnormalities that can cause psychosocial and social problems. Personality traits, body image, and self-concept are different in orthodontic applicants due to the different effects of malocclusions on appearance and psychological well-being. The aim of this study was to investigate the personality traits, body image, and self-concept in patients seeking orthodontic treatment in Tabriz-Iran in 1400.
Materials and Methods: The statistical population of the study included all patients requesting orthodontic treatment whom were referred to one of the orthodontic clinics in Tabriz during 1399-1400. This study was performed on 149 patients seeking orthodontic treatment (127 females and 22 males) by Convenience Sampling method. Neo personality traits, the Body Image Concern, and Marsh body self-concept questionnaires were used. SPSS software was used for data analysis.
Results: According to the results, neuroticism, agreement, conscience, extraversion and openness to experience were high in orthodontic patients (P<0.05). The average dissatisfaction with body image was high (P<0.05). Also, the body outside self-concept was low and the self-esteem was high (P<0.05).
Conclusion: Personality factors, body image, and self-concept are three effective psychological characteristics in patients seeking orthodontic treatment. Therefore, the request for orthodontic treatment is largely due to psychological factors such as differences in personality traits, body image, and self-concept.
Sania Azizi, Sepide Arab, Shima Younespour, Atefe Saffar Shahroudi,
Volume 37, Issue 0 (3-2024)
Abstract
Background and Aims: One side effect of orthodontic treatment is microcrack formation during debonding process. Since the type of ligation may affect the applied debonding force, this study was conducted to investigate the effect of ligation method on the enamel microcrack formation following debonding of orthodontic brackets.
Materials and Methods: The present study was an experimental in vitro study. 69 extracted human premolar teeth were divided into 3 groups with 23 teeth by a simple random method. A bracket was bonded on the buccal surface of the teeth, then the desired tooth was placed in a typodont where the rest of the teeth were mounted. Then, the arch wire was passively placed in the bracket slot. The samples were ligated by one of these three methods based on the study group: 1. Oring ligation 2. Tight ligation with a wire ligature for each tooth separately 3. Ligation of all arch teeth together, using a wire ligature. The buccal surfaces of the teeth were observed under a stereomicroscope and the length, location, and the number of microcracks were recorded before and after debonding process. In order to analyze the data, generalized estimating equation analysis was used.
Results: In all three groups, a significant increase was observed in the average total length and number of enamel microcracks following the debonding process. (P<0.001 in all three groups), with no statistically significant difference between the three study groups. However, it was greater in group 2 than that of groups 3 and 1 respectively. In general, the number of new cracks was more in mid-buccal area followed by cervical and occlusal areas.
Conclusion: The debonding process caused an increase in the average total length as well as the number of enamel microcracks. Type of ligation might affect the enamel microcrack formation so that in tight ligation group we had the greatest increase in the enamel damage especially in mid-buccal area of the tooth. Tight ligation method can cause more enamel cracks than O-ring ligation and full arch ligation methods.
