Posttreatment Stability Research Articles

Assessment of the effect of the corticotomy-assisted orthodontic treatment on the maxillary periodontal tissue in patients with malocclusions with transverse maxillary deficiency: a case series

BackgroundThe aim of the study was to assess the effect of corticotomy–assisted orthodontic treatment on soft tissue clinical parameters in patients with malocclusions with transverse maxillary deficiency.MethodsThe study included 20 generally healthy adult individuals with malocclusion, who underwent a corticotomy-assisted orthodontic treatment in maxilla. During the corticotomy performed after full-thickness flap elevation, only the buccal cortical plate was cut with the use of OTS-7, OTS7–4, OTS7-3 ultrasound tips of the piezosurgery device (Mectron s. p. a., Italy). A clinical examination was performed prior to the corticotomy procedure, then repeated – 3, 6, 9 and 12 months after the procedure. The following parameters were assessed: FMPI (full mouth plaque index), FMBOP (full mouth bleading on probing), PD (probing depth), CAL (clinical attachment level), GR (gingival recession height), RW (recession width), PH (papilla height), PW (papilla width), BS (bone sounding), biotype and KT.ResultsThere was a statistically significant reduction in PD (mean difference: 0.06; 95% Cl: − 0.33, − 0.18), CAL (mean difference: 0.07; 95% Cl: − 0.33, − 0.19), PH (mean difference: 0.26; 95% Cl: − 0.47, 0.05) and BS (mean difference: 0.13; 95% Cl: − 0.41, − 0.14) after the treatment. Statistically significant changes were also noted in relation to KT (mean difference: 0.17; 95% Cl: − 0.07, 0.27) and biotype (mean difference: 0.07; 95% Cl: 0.26, 0.39), which thickness increased significantly after the treatment. No statistically significant differences were observed in GR, RW and PW.ConclusionsThe corticotomy–assisted orthodontic treatment did not jeopardize the periodontal clinical status in maxilla. There is a need for further studies on a larger number of patient to compare the clinical findings with a control group as well as in patients with conventional orthodontic treatment in a longer follow-up time to find out more about the post-treatment periodontal tissue changes and stability.

Three-dimensional ultrasound evaluation of tongue posture and its impact on articulation disorders in preschool children with anterior open bite

BackgroundTongue posture plays an important role in the etiology of anterior open bite (AOB) and articulation disorders, and is crucial for AOB treatment planning and posttreatment stability. Clinical assessment of tongue posture in children is unreliable due to anatomical limitations. The aim of the study was to present functional diagnostics using three-dimensional ultrasound (3DUS) assessment of resting tongue posture in comparison to clinical assessment, and the associations between the improper tongue posture, otorhinolaryngological characteristics, and articulation disorders in preschool children with AOB.Patients and methodsA cross-sectional study included 446 children, aged 3–7 years, 236 boys and 210 girls, examined by an orthodontist to detect the prevalence of AOB. The AOB was present in 32 children. The control group consisted of 43 children randomly selected from the participants with normocclusion. An orthodontist, an ear, nose and throat (ENT) specialist and a speech therapist assessed orofacial and ENT conditions, oral habits, and articulation disorders in the AOB group and control group. Tongue posture was also assessed by an experienced radiologist, using 3DUS. The 3DUS assessment of tongue posture was compared to the clinical assessment of orthodontist and ENT specialist.ResultsThe prevalence of AOB was 7.2%. The AOB group and the control group significantly differed regarding improper tongue posture (p < 0.001), and articulation disorders (p < 0.001). In children without articulation disorders from both groups, the improper tongue posture occured less frequently than in children with articulation disorders (p < 0.001). After age adjustment, a statistical regression model showed that the children with the improper tongue posture had higher odds ratios for the presence of AOB (OR 14.63; p < 0.001) than the others. When articulation disorders were included in the model, these odds ratios for the AOB became insignificant (p = 0.177). There was a strong association between the improper tongue posture and articulation disorders (p = 0.002). The 3DUS detected the highest number of children with improper resting tongue posture, though there was no significant difference between the 3DUS and clinical assessments done by orthodontist and ENT specialist.ConclusionsThe 3DUS has proved to be an objective, non-invasive, radiation free method for the assessment of tongue posture and could become an important tool in functional diagnostics and early rehabilitation in preschool children with speech irregularities and irregular tongue posture and malocclusion in order to enable optimal conditions for articulation development.

Nonsurgical treatment and stability of an adult with a severe anterior open-bite malocclusion.

OBJECTIVES:A skeletal anterior open-bite is a challenging malocclusion for the orthodontist due to the difficulty and instability of correction. Treatment options for the adult patient include extractions, anterior extrusion with intermaxillary elastics, posterior intrusion using skeletal anchorage, occlusal adjustment, and orthognathic surgery. Patient compliance plays a key role in posttreatment stability. The present case report demonstrates the orthodontic treatment of an adult patient who presented with a complex open-bite malocclusion.MATERIALS AND METHODS:Treatment involved the placement of four miniscrews to assist intrusion of maxillary molars by applying posterior vertical maxillary elastics and extrusion of the anterior segments using anterior vertical interarch elastics.RESULTS:Ideal intercuspation was successfully achieved and good stability was maintained during 3 years following treatment.CONCLUSION:The intrusion of the maxillary molars with miniscrews is an interesting option in selected cases of skeletal anterior open bite. The retention protocol should be specific in these cases.

A clinical comparative evaluation of periodontally accelerated osteogenic orthodontics with piezo and surgical bur: An interdisciplinary approach.

Context:The orthodontic treatment in adult for the treatment of malocclusion is becoming more common. However, the disadvantages of conventional orthodontics are the time consumed for the treatment (18–24 months), root resorption, and formation of fenestrations and dehiscence. Periodontally accelerated osteogenic orthodontics (PAOO) is a surgical technique resulting in increased alveolar bone width, shorter treatment time, increase posttreatment stability, and decrease amount of apical root resorption.Aim:The aim of the study is to compare the treatment time, root resorption, bone density, and presence/absence of fenestrations and dehiscence after PAOO with surgical bur and PAOO with piezocision.Materials and Methods:Forty participants with bimaxillary protrusion undergoing orthodontic treatment were randomly selected and divided into two groups. Group I: 20 participants selected for PAOO with surgical bur and Group II: 20 participants selected for PAOO with piezocision. Patients were recalled at baseline 3, 6, 9, and 12 months and evaluated for treatment time and bone density, root resorption, and detection of fenestration and dehiscence using cone-beam computerized tomography (CBCT).Results:Participants in Group I had less treatment time compared to Group II. Rate of retraction was 7.07 mm/20.81 weeks and 5.99 mm/28.48 weeks in Group I and Group II, respectively. CBCT showed a statistically significant increase in bone density in both groups, 12 months after the surgery. Root resorption was negligible in Group I (0.34 mm) and in Group II (0.51 mm). CBCT revealed increase in thickness of alveolar bone and coverage of fenestrations and dehiscence.Conclusion:PAOO provides an efficient and stable orthodontic tooth movement.

Stability of anterior tooth alignment 10years out of retention.

Long-term posttreatment stability of anterior tooth alignment is of major interest to both patients and orthodontists. In the present study we examined the long-term outcome 10years postretention and investigated the possible influence of treatment-related factors on posttreatment stability of maxillary and mandibular anterior tooth alignment. The sample comprised 51 patients treated with full fixed appliances in a university clinic. Average retention time was 1.8years. All patients received a Hawley appliance in the maxilla and a bonded canine-to-canine retainer in the mandible. The Peer Assessment Rating (PAR)Index, Little's Irregularity Index (LII) and dental cast variables were recorded at pretreatment, posttreatment and 10years out of retention. Stability of occlusion was assessed with the PAR score percentage improvement method. For each jaw a multivariate regression analysis was performed to identify the influence of treatment-related factors on postretention tooth alignment. The PAR Index percentage improvement decreased from 73.1% posttreatment to 53.5% 10years out of retention. For both jaws posttreatment increase in anterior irregularity was significantly correlated with the degree of treatment correction. The strongest association was found in the maxilla. Premolar extractions were associated with increased stability of mandibular alignment. The need for retention appears to increase with the degree of alignment correction, particularly in the maxilla. Extraction of premolars significantly improved long-term stability of mandibular incisor alignment.

The mandibular muscles in contemporary orthodontic practice: a review.

It is widely accepted that all dentists should have a thorough understanding of the muscles involved in moving or stabilizing the mandible. However, there is still much discussion regarding the influence of the mandibular muscles on normal facial growth and dental development, as well as on orthodontic treatment and post-treatment stability. Potential patients with different underlying vertical muscle patterns will have differences in the expected directions of future mandibular growth, lateral profile shape, facial and arch widths and vertical occlusal relationships. In turn, thorough diagnoses are likely to lead to differences in individual aims and objectives, treatment plans, timing of commencement, mechanical design, lateral profile and smile-aesthetics outcomes, choice of retention and plans for long-term maintenance. The potential influence of the mandibular muscles on normal morphologic variation and the soft tissue implications on contemporary orthodontic treatment and stability will be addressed in this review.

Early interception of mandibular shifting: A longitudinal approach from deciduous through mixed and permanent dentitions

AbstractA Class II malocclusion with a unilateral posterior crossbite in the late deciduous dentition is a challenging type of malocclusion to intercept. The objective is to analyze the long-term changes in a patient with a skeletal Class II division 1 malocclusion. A 5-year-old female child who was referred from a pediatric dentist came for consultation. Correction of posterior crossbite involves expansion of the maxillary arch with the aim of removal of occlusal interferences and elimination of the functional shift of the mandible. The treatment comprised three stages: (1) Expansion of the maxillary arch was performed with a modified Haas palatal expander and the clinical procedures thus resulted in improved facial symmetry and satisfactory functional occlusion in the mixed dentition (8 years 10 months). (2) Distalization of maxillary first molars was done with a Kloehn type headgear and a lip bumper was placed in the mandible to maintain the arch perimeter (12 years). (3) A 0.022 inch × 0.028 inch standard edgewise fixed appliance was used for comprehensive orthodontic treatment and the objectives were accomplished (14 years 5 months). The results showed great improvements in function and esthetics, and posttreatment stability was good after 7 years and 5 months.

Indirect vs direct bonding of mandibular fixed retainers in orthodontic patients: Comparison of retainer failures and posttreatment stability. A 2-year follow-up of a single-center randomized controlled trial

The objectives of this 2-arm parallel trial were to compare the numbers of failures of mandibular fixed retainers bonded with indirect and direct methods and to investigate the posttreatment changes 2years after placement. Sixty-four consecutive patients from the postgraduate orthodontic clinic of the University of Geneva in Switzerland were randomly allocated to either an indirect or a traditional direct bonding procedure of a mandibular fixed retainer at the end of their orthodontic treatment (T0). Eligibility criteria were the presence of the 4 mandibular incisors and the 2 mandibular canines, and no active caries, restorations, fractures, or periodontal disease of these teeth. The patients were randomized in blocks of 4 (using an online randomization service) with allocation concealment secured by contacting the sequence generator for assignment. The patients were recalled 12months and 24months (T3) after retainer bonding. The main outcome was any first-time failure of retainers (ie, at least 1 composite pad debonded or fractured); unexpected posttreatment changes of the mandibular incisors and canines were a secondary outcome. Impressions and lateral cephalograms were taken at T0 and T3: changes in mandibular intercanine and interpremolar distances and mandibular incisor inclination were assessed. Blinding was applicable for outcome assessment only. The chi-square test and Cox regression were used to compare the survival rates of the retainers bonded with direct and indirect methods. Paired t tests were used to assess differences in intercanine and interpremolar distances and mandibular incisor inclination at T0 and T3. Significance was set at P<0.05. Sixty-four patients were randomized in a 1:1 ratio. One patient dropped out at baseline, and 3 patients did not reach the T3 recall. In 24 of 60 (40%) patients, the fixed retainer failed within 2years: 13 of 30 (43%) in the indirect bonding group and 11 of 30 (37%) in the direct bonding group (log-rank test, P=0.64). The hazard ratio was 1.26 (95% confidence interval, 0.56-2.81; P=0.58). Bond failures occurred mainly during the first year. There were no clinically significant changes in mandibular intercanine distance, interpremolar distance, and incisor inclination between T0 and T3, or between groups. In 5 patients (17%), all in the direct bonding group, unexpected posttreatment changes, systematically consisting in a lingual inclination of the mandibular left canine, were observed. In 1 patient (3%), the change was considered clinically severe. No other serious harm was observed. There was no difference in the risks of failure between mandibular retainers bonded with direct and indirect methods. Bonded retainers are effective in maintaining intercanine and interpremolar distances. There seem to be fewer unexpected posttreatment changes with retainers bonded with the indirect compared with the direct method. The trial was not registered. The protocol was not published before trial commencement. No funding or conflict of interest to be declared.

Retention considerations in the assessment of long-term stability in early versus late orthodontic treatment

Post-treatment stability is one of the most challenging aspects of orthodontic treatment and is a concern to all orthodontists. There are some important post-treatment factors that could influence the result, such as normal maturational changes, post-treatment tooth alterations, and persistent imbalance in the neuromuscular environments. Thus, early treatment brings about many benefits including better use of the patient's growth potential, less risk for adverse iatrogenic effects, better patient compliance, and potentially better outcomes, some with and others without retention management.

Effects of increased occlusal vertical dimension on the jaw-opening reflex in adult rats

ObjectiveMalocclusion with deep overbite and facial esthetics improve when facial height is intentionally increased during orthodontic extrusion of the posterior teeth. Thus, a better understanding of post-treatment stability of increased occlusal vertical dimension (iOVD) in adult patients is important. We focused on the jaw-opening reflex (JOR), which plays an important role in the control of jaw movements during mastication, and investigated the effects of iOVD on the JOR in rats with an electrophysiological technique. DesignOne hundred and twenty 13-week-old male Wistar rats were randomly divided into control and experimental groups. Rats in the experimental group received a 2-mm buildup of composite resin on the maxillary molars at 13 weeks of age. The JOR was induced by low-intensity electrical stimulation of the left inferior alveolar nerve. The electromyographic responses were recorded from the digastric muscle at 13, 14, 15, 17, 19, and 23 weeks of age. JOR properties including latency, duration, and peak-to-peak amplitude were measured and compared between the groups. ResultsThe latency of the JOR was significantly longer and the peak-to-peak amplitude was significantly smaller in the experimental group than in the control group from 14 to 19 weeks of age, while the reflex duration was not significantly different. Intra-group comparisons of the latency and peak-to-peak amplitudes among rats 14–19 weeks of age were significantly different between the experimental group and the control group. ConclusionsiOVD affected the latency and amplitude of the JOR but not the duration. The JOR adapted after 10 weeks of iOVD.

Evaluation of posttreatment stability after orthodontic treatment in the mixed and permanent dentitions.

To investigate posttreatment changes in the maxillary and mandibular arches in patients who underwent orthodontic treatment during the mixed and permanent dentitions. The sample was collected retrospectively from three private practices and consisted of 42 patients who were at least 10 years out of orthodontic treatment. The longitudinal records of study casts and cephalometric radiographs were analyzed to quantify posttreatment changes. Minimal changes in maxillary and mandibular irregularity occurred after an average of 16.98 years from completion of treatment. More than 10 years posttreatment, approximately 81% of the maxillary anterior teeth and 88% of the mandibular anterior teeth showed clinically acceptable incisor alignment (<3.5 mm). Mandibular fixed retainers greatly aided in maintaining the stability of the mandibular incisor alignment. However, posttreatment changes in maxillary incisor irregularity did not appear to be influenced by the presence of a mandibular fixed retainer. When compared with longitudinal changes observed in untreated subjects, the increase in incisor irregularity resembled a pattern similar to the regression line of untreated subjects and seems to be entirely age related. Arch width and arch depth was consistently decreased after treatment, but the magnitude of change was minimal at about 1 mm. No associations were found between any of the cephalometric measurements and changes in incisor irregularities. Orthodontic treatment stability can be achieved and mandibular fixed retention appears to be a valuable contributor, especially in patients with further growth expected.

Post-treatment Stability in Angle Class III Cases.

The purpose of this study was to compare post-treatment stability in Angle Class III cases grouped by treatment modality into extraction, non-extraction, or surgical. Twenty-seven Angle Class III patients (9 men, 18 women) were selected from among the records of qualified retention cases treated at the Department of Orthodontics, Tokyo Dental College. The patients were divided into the following groups: Group 1, extraction (n=10); Group 2, non-extraction (n=9); and Group 3, surgery (n=8). Lateral cephalograms, panoramic X-rays, and study casts were obtained at baseline (T0), after active treatment (T1), and after retention (T2). The ABO Model Grading System (ABO) and Gottlieb's Grading Analysis (GGA) were used as indices of occlusion, and the scores at each stage and differences in scores at T1 and T2 (|T1-T2|), defined as post-retention stability, recorded. Little's Irregularity Index (IRI) from the study casts and the ANB from lateral cephalograms at T0, T1, and T2 were also recorded to assess post-treatment stability from a different perspective. The Kruskal-Wallis test was performed for statistical comparisons. Mean ranking according to the ABO and Kruskal-Wallis test at T1, T2, and |T1-T2| was lowest in Group 1 and highest in Group 3, and the mean amount of change in the ABO score after active treatment was also the same. This suggests that post-treatment stability is highest in non-extraction cases and lowest in surgical cases. This result correlated with change in the ANB from T0 to T1. This indicates that amount of change in the ANB affects post-treatment stability and that relapse will tend to be greater in surgical cases. However, the amount of change in IRI after active treatment was highest in Group 2 and lowest in Group 3, suggesting that relapse of the lower incisors is greatest in non-extraction cases.

Evaluation of Outcome of Orthodontic Treatment in Context to Posttreatment Stability: A Retrospective Analysis

One of the main aims of orthodontic treatment is the improvement of esthetics along with enhancement of functions of the orofacial regions. Complications are observed even after final completion of the orthodontic treatment due to relapse and loss of stability. Hence, we retrospectively analyzed angle class I malocclusion cases to study the correlation of outcome of orthodontic treatment and posttreatment stability. A total of 100 patients were included in this retrospective analysis, which accounted for the patients reporting to the department of orthodontics from 2013 to 2015 with angle class I malocclusion. Pretreatment, posttreatment, and postretention casts of the patients were made and analyzed. The Richmond et al criteria was used to evaluate peer assessment rating (PAR) index and Little irregularity index, followed by scoring with American weight. Measurement of Pearson's coefficient was done to calculate the p-value. p-value of less than 0.05 was considered as significant. No significant amount of alteration was seen in the systematic errors of Little index and PAR index, while casual errors were also within the normal range. While comparing the PAR index at pretreatment and posttreatment phases, statistically significant results were obtained, whereas in case of Little index at same time intervals, scores showed nonsignificant results. Even after delivering ideal orthodontic treatment, stability of the treatment is still not ensured until unless posttreatment follow-up is properly maintained.

Use of leukocyte and platelet-rich fibrin (L-PRF) in periodontally accelerated osteogenic orthodontics (PAOO): Clinical effects on edema and pain.

BackgroundDemand for shorter treatment time is common in orthodontic patients. Periodontally Accelerated Osteogenic Orthodontics (PAOO) is a somewhat new surgical procedure which allows faster tooth movement via combining orthodontic forces with corticotomy and grafting of alveolar bone plates. Leukocyte and Platelet-Rich Fibrin (L-PRF) possess hard- and soft-tissue healing properties. Further, evidence of pain-inhibitory and anti-inflammatory potential is growing. Therefore, this study explores the feasibility, intra- and post-operative effects of using L-PRF in PAOO in terms of post-operative pain, inflammation, infection and post-orthodontic stability.Material and MethodsA pilot prospective observational study involving a cohort of 11 patients was carried out. A Wilcko’s modified PAOO technique with L-PRF (incorporated into the graft and as covering membrane) was performed with informed consent. Post-surgical pain, inflammation and infection were recorded for 10 days post-operatively, while the overall orthodontic treatment and post-treatment stability were followed up to 2 years.ResultsAccelerated wound healing with no signs of infection or adverse reactions was evident. Post-surgical pain was either “mild” (45.5%) or “moderate” (54.5%). Immediate post-surgical inflammation was either “mild” (89.9%) or “moderate” (9.1%). Resolution began on day 4 where most patients experienced either “mild” or no inflammation (72.7% and 9.1%, respectively). Complete resolution was achieved in all patients by day 8. The average orthodontic treatment time was 9.3 months. All cases were deemed stable for 2 years.ConclusionsL-PRF is simple and safe to use in PAOO. Combination with traditional bone grafts potentially accelerates wound healing and reduces post-surgical pain, inflammation, infection without interfering with tooth movement and/or post-orthodontic stability, over a 2 years period; thus alleviating the need for analgesics and anti-inflammatory medications. Key words:Periodontally accelerated osteogenic orthodontics, leukocyte and platelet-rich fibrin, corticotomy, osteogenesis, grafts.

Missing or Extraction of a Mandibular Incisor in Orthodontics

The extraction of a mandibular incisor constitutes a non-conventional alternative in treating certain anomalies. It is not a standard approach to symmetrically treating most malocclusions, but in some clinical situations the therapeutic aim must be adjusted to individual patient needs, even when this means that achieving final occlusion is not ideal. This treatment option may be indicated in malocclusions with anterior tooth size discrepancy due to narrow maxillary incisors and/or large mandibular incisors. It is contraindicated in malocclusions without anterior discrepancy or with discrepancies caused by large maxillary incisors and/or narrow mandibular incisors. The literature suggests that this method affords improved post-treatment stability compared with premolar extraction. A careful diagnosis, established with the aid of a diagnostic setup, professional skills and clinical experience are instrumental in achieving successful orthodontic results with this treatment option. The deliberate extraction of a mandibular incisor in certain cases allows the orthodontist to improve occlusion and dental esthetics. This article highlights the importance, indication, contraindications, advantages, disadvantages and stability of the results achieved in treatments performed with mandibular incisor extraction. Two clinical cases are presented illustrating the modality of such a treatment.

Bonded retainers maintain a high-standard orthodontic treatment outcome long term

BackgroundNumerous studies have demonstrated deterioration of orthodontic treatment outcome postretention; however, few studies present results in cases still in retention long term. The aim of the present study was to evaluate orthodontic treatment outcomes in patients with teeth still in retention at 10 years post-treatment. MethodsThis longitudinal study enrolled 108 children who received bonded lingual retainers after treatment with a full fixed appliance. Retainer extension and morphologic stability, as measured by weighted peer assessment ratings (wPAR), were recorded at pretreatment (t0), immediately post-treatment (t1), 5 years post-treatment (t5), and 10 years post-treatment (t10). The t10 results were compared with those from an untreated control group matched on age and sex. Post-treatment stability was additionally tested for correlation to age, sex, malocclusion, and extraction therapy. ResultsAt the group level, there was a significant mean reduction in wPAR of 74% at t10 (P < 0.001). Additionally, the mean wPAR was significantly better than was that in the control group. At the patient level, 57% of patients were categorized as “greatly improved.” The only factor that could be correlated to post-treatment changes (from t1 to t10) was the presence of at least one bonded retainer (P < 0.05). ConclusionA “high standard orthodontic treatment outcome” could be maintained 10 years post-treatment by keeping the bonded retainers in both the upper and lower arches. Orthodontic patients expect the aesthetics to be maintained over time. The results from this study, that bonded lingual retainers maintain the orthodontic treatment result for 10 years, are valuable information for the clinician when giving the patients advice and recommendations regarding retainer maintenance.

Lower incisor extraction: Can it be justified? A report of two cases

Extraction versus nonextraction debate is still continuing since 1900s. Some cases demand extraction of premolars, but the decision making is difficult in the border line cases with good facial esthetics. Lower incisor extraction becomes a therapeutic alternative to premolar extractions in lower anterior crowding cases with good facial esthetics and well occluded posterior teeth. Diagnostic setup reveals the posttreatment occlusal possibilities and hence the most important step in the diagnosis and treatment planning of these cases. Lower incisor extraction decision would be a better option in cases with anterior Bolton's discrepancy. Two cases treated with single lower incisor extraction, indications, contraindications and measures to attain posttreatment stability are discussed in this presentation.

An Overview on Interproximal Enamel Reduction

Ever since its first introduction seven decades ago, there has been continuous advancement of the concept and technique of Interproximal enamel reduction (IPR). It’s demonstrated that with correct case selection and clinical performance, IPR is safe and effective for alleviating crowding, improving dental and gingival aesthetics as well as facilitating post-treatment stability. The fulfilment of treatment outcomes depends on careful pre-treatment examination and planning, appropriate clinical procedures and effective post-treatment protection. This review aims to provide a general introduction to IPR in terms of its history background, risks and benefits and clinical performance.

모형과 방사선 사진을 이용한 하악 전치 발치 치료의 안정성 평가 - 미국교정학회에서 제시한 방법

Purpose: The purpose of this study was to evaluate the improvement and posttreatment stability of patients treated with extraction of lower incisors. Materials and Methods: The total of 20 patients with extracted lower incisors were analyzed by means of diagnostic models and panoramic x-rays at the time of initial, final and after 2 years of retention period of the treatment. Irregularity index, overjet, overbite, tooth size-arch length discrepancy (TSALD), intercanine width, intermolar width and American Board of Orthodontics cast/radiographic evaluation (ABO-CRE) were analyzed. Statistical analysis was performed using Wilcoxon signed-rank test. Results: After treatment, irregularity index showed significant decrease (P

Residents' journal review

Residents' journal review