Difference In Root Resorption Research Articles

The effect of piezocision in canine distalization: A prospective split-mouth study

: This study evaluated the duration for distalization of canine and the amount of root resorption with and without piezocision. : The study sample consisted of 15 adult patients in a prospective split-mouth study design, requiring therapeutic extraction of bilateral maxillary first premolar and bilateral canine distalization. The subjects were evaluated for the time taken for the maxillary canine to achieve a positive contact with the maxillary second premolars bilaterally. Intervention in form of piezocision was carried out on one side of the maxillary arch using piezotome vis-a viz the control side. The study further uses pre & post CBCT records to evaluate the amount of blunting of the maxillary canine root apexes bilaterally when distalization was completed. : Duration of canine retraction in the piezocision group was 4.66 ± 0.52 months which is comparatively faster than that of the control group which took almost 5.72 ± 0.65 months. : The study concluded that the use of piezocision in cases of individual maxillary canine retraction results in a shorter duration of maxillary canine distalization and overall treatment time, with no significant difference in root resorption with or without piezocision.

Comparative Evaluation of Orthodontically-Induced Root Resorption Using Cone Beam Computed Tomography (CBCT) and Orthopantomogram (OPG) During En-Masse Retraction of Maxillary Anterior Teeth.

Orthodontically induced apical root resorption is an inescapable consequence of fixed orthodontics. This root resorption causes post-orthodontic complications in some treated cases. To avoid these complications proper diagnosis of the site and amount of resorption is important. The aim of this study was to compare the diagnostic ability of Orthopantomogram (OPG) and Cone Beam Computed Tomography (CBCT) in detecting apical root resorption after en-masse retraction of maxillary anterior teeth in a sample of Saudi Arabian population. The study sample comprised of 30 patients diagnosed with bimaxillary dentoalveolar protrusion. The treatment plan involved extraction of all first premolars followed by en-masse retraction of the anterior teeth. OPG images were obtained at the beginning of treatment and after the end of the retraction phase and a CBCT image were also obtained for the same patient at the same centre other than orthodontic reason like implant placement, temporomandibular joint (TMJ) problems, sleep apnea, etc. after orthodontic treatment completion. The scoring system of Levander and Malmgren was used to assess the degree and severity of root resorption in the maxillary incisors. Dalhbergs error and coefficient of reliability (ICC) were used to calculate the correlation between the two sets of readings.Pearson chi-square test was used to compare the difference in root resorption between OPG and CBCT images. A P-value of <0.05 was considered to be statistically significant. No resorption was observed in 39.2%and 16.6% of incisors with OPG and CBCT respectively. Mild resorption was observed in 50% and 66.7% of incisors with OPG and CBCT respectively. Moderate resorption was found in 10% and 15% of incisors with OPG and CBCT respectively. Severe root resorption was found in 0.8% and 1.7% of incisors with OPG and CBCT respectively. Statistically, significant differences were found in both methods of evaluation in all grades of root resorption for all the maxillary incisors (P<0.05). OPG had consistently underestimated the amount of orthodontically induced apical root resorption when compared to CBCT. OPG is only useful for the primary evaluation of root resorption. CBCT can be used as an adjunct diagnostic tool on a case-to-case basis in patients with moderate to severe root resorption to manage post-orthodontic treatment complications.

T-loop spring vs ricketts maxillary canine retractor in canine retraction efficacy and anchorage loss control: A cone-beam computed tomography study

This study aimed to compare the Burstone technique using the T-loop spring (TLS) and Ricketts maxillary canine retractor (RMCR) in canine retraction efficacy and anchorage loss control using cone-beam computed tomography. Data was taken from 31 patients with maxillary canine retraction using either the Burstone technique, in which an off-centered TLS was applied (TLS group, n = 14), or Ricketts technique, in which the RMCR was applied (RMCR group, n = 17). Cone-beam computed tomography images were obtained before and after retraction. The evaluated outcomes were the vertical and sagittal movement amounts of the centers of resistance, the tipping, the rotation, and the buccolingual inclination of both canine and molar, in addition to the amount of root resorption of the canine. Using the TLS demonstrated a significantly greater amount of canine retraction and intrusion ( P = 0.003; P = 0.002) and fewer degrees of mesial-out rotation ( P = 0.004) than the RMCR. No significant differences in canine tipping and inclination were found. The difference in root resorption was also insignificant. No significant differences were found in molar linear and angular movement changes , except for the anteroposterior tipping direction (P <0.001). The molar protracted bodily with the TLS and tipped mesially with the RMCR. The TLS can control the sagittal canine movement more effectively than the RMCR, whereas the RMCR can better control the canine movement vertically. Both springs can cause a similar and significant amount of canine root resorption. The molar tends to tip distally when the TLS is used, and it tips mesially when the RMCR is used, with a significant difference between the methods.

The influence of bracket torque on external apical root resorption in bimaxillary protrusion patients: a retrospective study

BackgroundTo evaluate the difference in root resorption between standard torque self-ligating brackets and high torque self-ligating brackets in bimaxillary protrusion patients after orthodontic treatment.MethodsPre-treatment and post-treatment Cone beam computed tomography (CBCT) of 32 patients (16 treated with the high torque DamonQ 0.022″ bracket and 16 with the 0.022″ standard torque self-ligating bracket) were selected. The first premolars were extracted from all patients before treatment. After mini-screw implants were inserted into the buccal region between the second premolar and first molar, 150 g of force was applied to retract the upper and lower anterior teeth to close the extraction space on each side. CBCT images of all patients were taken before and after treatment. Three-dimensional reconstruction of the maxillary central incisor, lateral incisor and canine was conducted with Mimics 20.0 software. The volumes of the roots were calculated using Gomagics Studio 12.0 software. The differences between the pre-treatment and post-treatment root volumes were statistically evaluated with a paired-samples t-test.ResultsThere was no statistically significant difference in root resorption degree between the two kinds of torque brackets. The patient’s degree of root resorption in the high torque self-ligating group was greater than that in the standard torque group.ConclusionsThere was no significant difference in root external apical resorption between the high torque self-ligating brackets and the standard torque self-ligating brackets in bimaxillary protrusion patients.

Comparative Evaluation of Root Resorption in Correction of Class II Malocclusion

INTRODUCTION: External apical root resorption is a common iatrogenic side effect of orthodontic treatment and has been reported particularly in anterior teeth. The etiology of resorption is multifactorial, complex and individual susceptibility to resorption depends on various factors.MATERIALS AND METHOD: The degree of root resorption during orthodontic treatment was evaluated on the post-treatment RVGs of the maxillary and mandibular central and lateral incisors of 28 skeletal Class II patients with mandible retrusion treated with non-extraction treatment protocol using elastics and PowerScope. RESULTS: There was no statistically significant difference in root resorption between the groups for the overall score and comparison of root resorption in individual teeth between two groups showed significantly more resorption in PowerScope group in mandibular lateral incisors.CONCLUSION: Both elastic and PowerScope groups showed mostly mild to moderate root resorption which is clinically acceptable and lower lateral incisors showed statistically more root resorption in PowerScope group.

Comparison of Rate of Canine Retraction and Secondary Outcomes Associated With Conventional Fixed Orthodontic Treatment and Minimally Invasive Techniques (MOPs): A Randomized Control Trial

Introduction: The objective of the study was to assess the rate of canine retraction and secondary outcomes associated with conventional fixed orthodontic treatment (CFO) and CFO with micro-osteoperforation (CFO + MOP), that is, anchorage loss, root resorption, vitality of tooth, pain and discomfort level during the procedure. Methods: A total of 16 patients with Class II Division 1 malocclusion who required upper first premolar extraction with lower non-extraction/single incisor extraction were divided into the test group (MOP) and positive control group (CFO + MOP) for a split-mouth study. Both maxillary canines were retracted with nickel–titanium (NiTi) closed coil springs. Patients were reviewed after 24 hours, 7 days, 28 days, and 4, 8, and 16 weeks to assess the rate of tooth movement, anchorage loss, root resorption, vitality of tooth, pain and discomfort level. Results: There was a statistically significant difference in the rate of tooth movement between the CFO and CFO + MOP groups after the first 4 weeks ( P-value = .026), whereas no statistically significant difference was observed at 8, 12, and 16 weeks ( P-value = .33, .99, and .08, respectively). In the CFO group, there was no statistically significant difference in tooth movement between different time intervals ( P-value &gt; .05). There was no significant difference in root resorption between the groups. The pain level was higher in the MOP group in the first 24 hours ( P-value &lt; .05) after the procedure. Later on, the difference in pain level between the groups was not significant ( P-value &gt; .05). The vitality of retracted canines in both groups was healthy. Conclusion: The study recommends that the CFO + MOP procedure has substantial potential to be used as an adjunct to the routine mechanotherapy for faster tooth movement, as it may reduce the treatment time by half in the first 4 weeks after the MOP procedure. There are no potential differences in anchorage loss, tipping, vitality, and apical and lateral root resorption between the CFO and CFO + MOP groups. This trial was registered at Clinical Trial Registry, India.

Evaluation of root resorption after orthodontic treatment: A clinical study of contributory factors

Introduction: The aim of this study was to evaluate the contributory factors of external apical root resorption. Materials and Methods: Sixty subjects who had undergone complete orthodontic treatment were selected. The difference of the root length between pre and post-treatment was measured. The degree of root resorption was scored according to the index proposed by Levander and Malmgren. 1 The mean root resorption score (MRRS) was calculated. Mann Whitney test was done to compare the groups. Pearson correlation was applied. Results: There was no statistically significant difference in root resorption among males and females. Tooth extraction was correlated with MRRS. Except for upper posterior teeth, the duration of treatment was positively correlated with MRRS. For overjet, there was a positive correlation between upper and lower anterior teeth and MRRS. Conclusion: Orthodontic treatment should be carefully performed in patients who need extraction, great retraction of maxillary incisors and prolonged therapy. Keywords: Root resorption, Fixed orthodontic treatment forces.

Injectable RANKL sustained release formulations to accelerate orthodontic tooth movement.

Accelerating orthodontic tooth movement (OTM) through biologically effective methods, such as increasing osteoclast-mediated alveolar resorption, could effectively shorten treatment time. To evaluate an injectable formulation containing receptor activator of nuclear factor kappa-B ligand (RANKL) on the OTM. We fabricated a RANKL formulation from 100 µl of 100 µg/ml RANKL adsorbed on 10 mg of poly(lactic acid-co-glycolic acid) microspheres embedded in a 10 wt% aqueous hydroxyethyl cellulose carrier gel. We characterized these formulations for the rate of RANKL release, and then tested for bioactivity using in vitro cell culture. In vivo OTM studies were conducted using 15 week old male Wistar rats for 14 days. We injected the RANKL formulations palatal to the left maxillary first molar and accomplished OTM with a nickel-titanium (NiTi) coil spring applying 5-8 g force. Control groups involved the application of NiTi coil spring with and without placebo formulation. The outcome measure included the distance of tooth movement, bone volume fraction, tissue density, and root volume determined with micro-computed tomography. We determined the amount of osteoclast activity using tartrate-resistant acid phosphatase (TRAP) staining. These formulations were able to sustain the release of RANKL for more than 30 days, and the released RANKL showed a positive effect on mice osteoclast precursor cells (RAW 264.7). Reported injectable RANKL formulations were effective in accelerating OTM compared with other control groups, with 129.2 per cent more tooth movement than no formulation and 71.8 per cent more than placebo formulation, corresponding with a significant increase in the amount of TRAP activity. We did not observe any significant differences in root resorption between the groups. Our study shows a significant increase in OTM with injectable formulations containing RANKL.

Effects of different force magnitudes on corticotomy-assisted orthodontic tooth movement in rats.

To investigate the effects of light and heavy forces with corticotomy on tooth movement rate, alveolar bone response, and root resorption in a rat model. The right and left sides of 40 male Wistar rats were randomly assigned using the split-mouth design to two groups: light force with corticotomy (LF) and heavy force with corticotomy (HF). Tooth movement was performed on the maxillary first molars using a nickel-titanium closed-coil spring delivering either 10 g (light force) or 50 g (heavy force). Tooth movement and alveolar bone response were assessed by micro-computed tomography (micro-CT) at day 0 as the baseline and on days 7, 14, 21, and 28. Root resorption was examined by histomorphometric analysis at day 28. Micro-CT analysis showed a significantly greater tooth movement in the HF group at days 7 and 14 but no difference in bone volume fraction at any of the observed periods. Histomorphometric analysis found no significant difference in root resorption between the LF and HF groups at day 28. Heavy force with corticotomy increased tooth movement at days 7 and 14 but did not show any difference in alveolar bone change or root resorption.

Intrinsic Hormone-Like Molecules and External Root Resorption During Orthodontic Tooth Movement. A Systematic Review and Meta-Analysis in Preclinical in-Vivo Research.

Background: External root resorption constitutes an adverse effect of orthodontic treatment. The aim of the present meta-analysis was to identify the effect of induced intrinsic/ hormone-like molecules such as prostaglandins, interleukins and others on external root resorption after orthodontic tooth movement in experimental animalsMethods: An electronic database search of the literature was performed (Medline via PubMed, EMBASE, LILACS, and Open Gray). Search terms included root resorption, tooth movement and animal type. Risk of bias assessment was made using the SYRCLE guidelines for animal studies and reporting quality was assessed through ARRIVE. Random effects meta-analysis was performed for the outcome root resorption after orthodontic tooth movement.Results: Of the 124 articles initially retrieved, 13 were eligible for inclusion in the systematic review, while only 2 were included in the quantitative synthesis. Five studies investigated the effect of Prostaglandin E2, four studies the effect of Thyroxine, two the effect of Calcium ions (Ca++), while the rest investigated Misoprostol, Interleukin-12 and Interleukin-4. Risk of Bias in all studies was judged to be high overall, while reporting quality was suboptimal. According to the quantitative synthesis, there was no difference in root resorption after orthodontic tooth movement when Prostaglandin E2 coupled with Ca++ was administered in comparison to no substance administration (SMD: 0.48 mm2; 95% CI: −0.22, 1.19; p = 0.18).Conclusions: Overall, there was no evidence to suggest a variation in root resorption when Prostaglandin E2 and Ca++ were administered, while there is an overriding need for further high quality experimental studies to inform available evidence on the effect of intrinsic substances on external root resorption.

Differences in Root Resorption between Root Canal treated and contralateral vital tooth during Orthodontic Tooth Movement: A Systematic Review

It is believed that root canal treated tooth apex goes under more resorption than contralateral vital tooth during orthodontic movement. The concept is still contradictory and therefore the aim of this systematic review was to search the evidence regarding this issue. The clinical trials performed on human subjects with vital and contralateral root canal treated tooth were included in the study. The evidence was searched in PubMed, EMBASE, Medline, Cochrane and Scopus. No language barrier was imposed. From analysis it found that there was no difference in amount of root resorption between vital and contralateral tooth. But, degree of resorption was determined by the intensity of force applied, force application technique (continuous or interrupted), duration of force application and direction of force application. Form the above fact it can be concluded that root canal treated tooth can be moved equal distance as vital contralateral tooth.Orthodontic Journal of Nepal, Vol. 6 No. 1, June 2016, pp.41-44

Correlation Between Orthodontic Forces and Root Resorption – a Systematic Review of the Literature

Abstract Orthodontically induced external apical root resorption (OIEARR) is a major concern regarding periodontal status after nonsurgical orthodontic treatment. The aim of this study was to assess this sequel by a systematic review of published data. For assessment, we performed an electronic search of one database for comprehensive data, using keywords in different combinations: “root resorption”, “periodontics” and “nonsurgical orthodontic treatment”. We supplemented the results searching by hand in published journals and we cross-referenced with the accessed articles. Patients included in the results presented a good general health status, with no previous history of OIEARR and no other associated pathologies. Finally, twenty-three studies were selected and included in this review. A high prevalence (69–98%) and moderate severity of OIEARR (&lt;5 mm and &lt;1/3 from original root length) were reported. No difference in root resorption was found regarding the sex of the patients. A moderate positive correlation between treatment duration and root resorption was found. Also, a mild correlation regarding antero-posterior apical displacement and root resorption was found.

Evaluation and comparison of root resorption between tooth-borne and tooth-tissue borne rapid maxillary expansion appliances: A CBCT study.

To compare volumetric root resorption after rapid maxillary expansion (RME) between tooth-borne and tissue-borne appliances using CBCT. Repair in resorption cavities after 6 months of fixed retention was also compared. A sample of 33 subjects were randomly divided into two groups: Hyrax (n = 16) and Haas (n = 17). CBCT scans were taken 6 months before expansion, immediately after expansion, and 6 months after fixed retention. Mimics Innovation V 16.0 software was used for segmentation and volumetric measurement of 198 teeth. Bland-Altman plots, independent samples t test, repeated measures analysis of variance, and the Friedman test were used for statistical analysis. Differences in root resorption after RME and repair after retention were not significant between the hyrax and Haas appliances or between male and female. Significant differences were found between preexpansion and postexpansion root volumes in the first premolars and molars--even in unattached second premolars. When the percentage of root volume loss is considered, no significant difference was found between the first premolar, second premolar, and first molar. Volumetric changes after 6 months of retention were not statistically significant. More resorption was observed in the Hyrax expander group. But it was not statistically significant. Repair was observed after 6 months of retention. Heavy RME forces affected premolars and molar similarly.

Are interventions for accelerating orthodontic tooth movement effective?

Pubmed, Embase, Sciences Citation Index, Cochrane Central Register of Controlled Trials (CENTRAL) and grey literature database of SIGLE were searched from January 1, 1990 to August 20, 2011 with no language restrictions. Randomised controlled trials (RCTs) or quasi-RCTs in which the participants were healthy and received additional interventions to conventional orthodontic treatment for accelerating tooth movements were included. Subjects with defects in oral and maxillofacial regions (ie, cleft lip/palate), dental pathologies and medical conditions were excluded. Studies were selected by two independent reviewers and disagreements were resolved by discussion with a third reviewer. The primary outcomes included accumulative moved distance (AMD) or movement rate (MR) and time required to move the tooth to its destination. Secondary outcomes were pain improvement, anchorage loss, periodontal health, orthodontic caries, pulp vitality and root resorption. The reviewers performed statistical pooling, where possible, according to a priori criteria on the basis of comparability of patient type, treatments and outcomes measured and risk of bias. The reviewers tested for heterogeneity, publication bias and sensitivity. A quality assessment test was conducted to evaluate the method used to measure AMD. The authors selected seven RCTs and two quasi-RCTs, which included a total of 101 patients with an age range of 12-26.3 years. Eight studies compared four intervention methods to no intervention group (control group). From them, four studies assessed low laser therapy (LLL), two evaluated corticotomy (CC), one assessed electrical current therapy (EC) and one evaluated pulsed electromagnetic field (PEF). Another study compared dentoalveolar distraction (DAD) vs periodontal distraction (PDD).Quality assessment scores showed that only two studies were of high quality, five studies were of medium quality, while two studies were of low quality. All studies, except one, compared left and right sides of the same participant (split mouth design), and measured the AMD.The method for measuring AMD was reliable in three studies, relatively reliable in one study and unreliable in four studies. The authors only performed pooled AMD mean meta-analysis for the LLL studies. The meta-analysis showed pooled mean AMD of 0.32 (95% confidence interval (CI), 20.04, 0.68), 0.76 (95% CI, 20.14, 1.65), and 0.73 (95% CI, 20.68, 2.14) for one month, two months and three months, respectively. Two LLL studies showed no differences regarding periodontal health and two LLL studies showed no differences in root resorption between LLL intervention and control groups. Compared to control group, one study reported that CS had significantly higher MR and another study showed that CS exhibited larger AMD for one month, two months, three months and four months. Two studies revealed that CS did not show any difference in the periodontal health status. One study reported the EC showed significantly larger AMD for one month, whereas another study reported that PEF induced larger AMD for five + 0.6 months. DAD showed faster MR and less anchorage loss compared to PDD. Teeth remained vital in both DAD and PDD interventions and one out of six cases presented root resorption in the PDD group. Among the five interventions corticotomy is effective and safe to accelerate orthodontic tooth movement, low-level laser therapy was unable to accelerate orthodontic tooth movement. The level of evidence does not support whether electrical current and pulsed electromagnetic fields are effective in accelerating orthodontic tooth movement and dentoalveolar or periodontal distraction is promising in accelerating orthodontic tooth movement.

Radiologically determined orthodontically induced external apical root resorption in incisors after non-surgical orthodontic treatment of class II division 1 malocclusion: a systematic review.

This study aims to critically evaluate orthodontically induced external apical root resorption (OIEARR) in incisors of patients undergoing non-surgical orthodontic treatment of class II division 1 malocclusion by a systematic review of the published data. An electronic search of two databases was performed; the bibliographies of relevant articles were also reviewed. Studies were included if they examined the amount of OIEARR in incisors produced during non-surgical orthodontic treatment of individuals with class II division I malocclusion in the permanent dentition. Individuals had no previous history of OIEARR, syndromes, pathologies, or general diseases. Study selections, risk of bias assessment, and data extraction were performed in duplicate. Eight studies of moderate methodological quality were finally included. An increased prevalence (65.6% to 98.1%) and mild to moderate severity of OIEARR (<4 mm and <1/3 original root) were reported. No sex difference in root resorption was found. For the maxillary incisors, there was no evidence that either the central or lateral incisor was more susceptible to OIEARR. A weak to moderate positive correlation between treatment duration and root resorption, and anteroposterior apical displacement and root resorption was found. Current limited evidence suggests that non-surgical comprehensive orthodontic treatment to correct class II division 1 malocclusions causes increased prevalence and severity of OIEARR the more the incisor roots are displaced and the longer this movement takes.

External apical root resorption in maxillary incisors in orthodontic patients: associated factors and radiographic evaluation

PurposeThis study was performed to evaluate the incidence and degree of external apical root resorption of maxillary incisors after orthodontic treatment and to evaluate particular associated factors related to external apical root resorption.Materials and MethodsThe records and maxillary incisor periapical radiographs of 181 patients were investigated. Crown and root lengths were measured and compared on the pre- and post-treatment periapical radiographs. Crown length was measured from the center of the incisal edge to the midpoint of the cemento-enamel junction (CEJ). Root length was measured from the CEJ midpoint to the root apex. A correction factor for the enlargement difference was used to calculate root resorption.ResultsThe periapical radiographs of 564 teeth showed that the average root resorption was 1.39±1.27 (8.24±7.22%) and 1.69±1.14 mm (10.16±6.78%) for the maxillary central and lateral incisors, respectively. The results showed that the dilacerated or pointed roots, maxillary premolar extraction cases, and treatment duration were highly significant factors for root resorption (p<0.001). Allergic condition was a significant factor at p<0.01. Age at the start of treatment, large overjet, and history of facial trauma were also factors significantly associated with root resorption (p<0.05). There was no statistically significant difference in root resorption among the factors of gender, overbite, tongue-thrusting habit, types of malocclusion, and types of bracket.ConclusionThese results suggested that orthodontic treatment should be carefully performed in pre-treatment extraction patients who have pointed or dilacerated roots and need long treatment duration.

English

To study predictors of root resorption in orthodontic treatment from 407 records, 377 pre- and post- treatment periapical radiographs of permanent maxillary central incisors of 199 patients treated with fixed appliances were divided according to overjet, overbite, age, gender and endodontic treatment. Changes in root length between the onset and completion of orthodontic treatment were measured in digitized images and statistically compared using student t, one-way ANOVA and Tukey tests. There was no correlation between increased overjet, overbite and root resorption or with anterior open bite (0.924 and 0.5772). Root resorption was significantly lower in children younger than 10 years when compared to adults (P = 0.0017) and even lower in adolescents when compared to adults (P = 0.0003). There was higher prevalence of root resorption in males simultaneously with higher number of pipette-shaped and dilacerated apical root morphology (P = 0.034). Endodontically treated teeth were not more susceptible to root resorption (P = 0.208). Increased overjet and overbite did not present positive relation with root resorption. There was no difference in root resorption between vital and endodontically treated teeth. Age and gender presented positive relation with root resorption. Susceptibility to root resorption during orthodontic treatment may be related to apical morphology. &nbsp; Key words:&nbsp;Root resorption, orthodontic treatment, tooth movement.

Study of external root resorption during orthodontic treatment in root filled teeth compared with their contralateral teeth with vital pulps

To determine whether root filled teeth and those with vital pulps exhibit a similar degree of external root resorption (ERR) as a consequence of orthodontic treatment. The study sample consisted of 77 patients, with a mean age of 32.7 +/- 10.7 years, who had one root filled tooth before completion of multiband/bracket orthodontic therapy for at least 1 year. For each patient, digital panoramic radiographs taken before and after orthodontic treatment were used to determine the proportion of external root resorption (PRR), defined as the ratio between the root resorption in the root filled tooth and that in its contralateral tooth with a vital pulp. The student's t-test, anova and logistic regression analysis were used to determine statistical significance. The mean PRR was 1.00 +/- 0.13, indicating that, in the total sample, there were no significant differences in root resorption in the root filled teeth and their contralateral teeth with vital pulps. Multivariate logistic regression analysis suggested that PRR was significantly greater in incisors (P = 0.0014; odds ratio = 6.2885, C.I. 95% = 2.0-19.4), compared to other teeth, and in women (P = 0.0255; odds ratio = 4.2, C.I. 95% = 1.2-14.6), compared to men. There was no significant difference in the amount or severity of external root resorption during orthodontic movement between root filled teeth and their contralateral teeth with vital pulps.

Root resorption before and after orthodontic treatment: a clinical study of contributory factors

This clinical study evaluated factors related to root resorption before (T1) and after (T2) orthodontic treatment. Ninety-six subjects between 9 and 34 years (34 males and 62 females) who had been treated using fixed appliances for at least 1 year and who had panoramic radiographs at T1 and T2 were selected. The relationship between root resorption at T1 and T2, with regard to gender, age, extraction versus non-extraction patterns, specific teeth and treatment duration was investigated. No statistically significant differences in root resorption were found in relation to gender. Significant differences in root resorption (P = 0.000, P < 0.01) and also in treatment duration (P = 0.036, P < 0.05) were noted between the extraction and non-extraction groups; extraction and treatment duration correlated with T2 mean root resorption. Patient age correlated with root resorption of the upper incisors at T1 and T2. Using multiple regression analysis, age and duration of treatment were found to be more associated with root resorption than with extractions; the presence of root resorption at T1 was associated with T2 root resorption, especially of the anterior teeth.

Apical root resorption of maxillary first molars after intrusion with zygomatic skeletal anchorage.

The aim of this study was to evaluate radiographically the apical root resorption of maxillary first molars after their intrusion was done using zygomatic miniplates as skeletal anchorage in open-bite cases. The study group comprised 16 consecutively treated open-bite cases who had received special titanium miniplates in their zygomatic bones for use as anchorage to apply orthodontic intrusive forces to the maxillary posterior region. The control group consisted of 16 patients, who were matched regarding age, sex, and treatment duration but who had undergone fixed orthodontic treatment without intrusion mechanics for molars. Tooth lengths were measured on pretreatment, and posttreatment panoramic radiographs of all patients and mesiobuccal and distobuccal roots of left and right maxillary first molars were measured on-screen using a software program. The difference between the pre- and posttreatment tooth lengths was defined as apical root resorption. Comparison of the differences in root resorption of the two groups using the t-test for independent samples showed a statistically significant difference (P = .004) only for mesial roots on the right side. But because the mean difference in apical root resorption was only 0.5 mm, it was concluded that the apical root resorption of maxillary first molars after intrusion was done using zygomatic skeletal anchorage was not clinically significant.