Changes of maxillary central incisor and alveolar bone in Class II Division 2 nonextraction treatment with a fixed appliance or clear aligner: A pilot cone-beam computed tomography study

Comparative analysis of root resorption and alveolar remodeling in maxillary incisors during orthodontic-orthognathic surgical treatment of skeletal Class III malocclusion

INTRODUCTION

This retrospective clinical study investigated root length and periodontal changes around maxillary incisors in patients with Class III skeletal malocclusion treated with fixed appliances (FAs) and clear aligners (CAs) by cone-beam computed tomography.

METHODS

A total of 60 patients were equally divided into 2 groups based on the appliance type; cone-beam computed tomography scans were obtained before treatment, after presurgical orthodontic treatment, and after orthodontic-orthognathic treatment. The measurements of root length, vertical alveolar bone level, and horizontal alveolar bone thickness at 4 levels (3, 6, and 9 mm from the cementoenamel junction and root apex level) surrounding the maxillary incisors were compared. The tooth movement of maxillary incisors during the presurgical phase was evaluated.

RESULTS

The root length of maxillary incisors decreased in both groups, with the CA group experiencing a small reduction (1.09 ± 0.70 mm) compared with the FA group (1.29 ± 0.73 mm) after treatment. The FA group showed more pronounced reductions in palatal alveolar bone thickness and vertical alveolar bone level, along with greater root lingual movement during the presurgical orthodontic phase. Postsurgically, although both groups saw an increase in labial incisor inclination, the FA group primarily exhibited root lingual movement, as opposed to the labial tipping movement observed in the CA group.

CONCLUSIONS

The results indicated that FAs and CAs could trigger root resorption and marginal alveolar bone loss, with FA treatment associated with a more pronounced impact. Although CA may offer advantages in minimizing root resorption and conserving alveolar bone integrity, it provides inferior control over anterior torque compared with FA. Careful consideration is crucial to prevent iatrogenic degeneration during the whole phase of orthodontic-orthognathic surgical treatment.

Volumetric and tridimensional root resorption and alveolar bone changes in Class II malocclusion extraction protocol treated with clear aligners and fixed orthodontic appliances: A comparative study

INTRODUCTION

This study aimed to assess the root resorption and alveolar bone changes of maxillary incisors volumetrically and 3-dimensionally in patients with Class II Division 1 malocclusion who underwent treatments involving the extraction of 4 first premolars with conventional fixed appliances (FAs) vs clear aligners (CAs).

METHODS

A total of 320 maxillary incisors from 80 patients were assessed and divided into 2 groups (FAs and CAs), each possessing similar baseline characteristics. Pretreatment and posttreatment cone-beam computed tomography scans were used to analyze linear and volumetric orthodontically induced inflammatory root resorption, alveolar bone thickness (ABT), alveolar bone height (ABH), as well as anteroposterior and vertical movements of maxillary incisors.

RESULTS

Both groups revealed a significant reduction in palatal ABT and an increase in labial ABT in both the central and lateral incisors. The total ABT reduction was more pronounced in the FAs group than in the CAs group (P <0.005). In terms of ABH, FAs treatment resulted in more labial and palatal marginal alveolar bone resorption around the maxillary incisors. The root length and volume losses in the CAs group were significantly less than those in the FAs group: 0.90 ± 0.97 vs 1.85 ± 1.18 mm and 19.59 ± 8.75 vs 24.28 ± 10.05 mm3, respectively. The axial inclination was significantly less in the CAs group than in the FAs group: 8.83 ± 8.73 vs 2.64 ± 12.31°.

CONCLUSIONS

Treatments of Class II Division 1 malocclusion with FAs and CAs appeared to cause a statistically significant palatal ABT reduction and maxillary incisors root resorptions, with the FAs treatment causing a more significant effect. Both treatment modalities significantly reduced the ABH, with the greatest reduction found on the lateral incisors' palatal side in the FAs group. The CAs treatment resulted in a more significant incisor lingual tipping.

Changes in alveolar bone remodeling after maxillary anterior retraction using fixed appliances with different periodontal conditions: A retrospective study based on cone-beam computed tomography

INTRODUCTION

This study aimed to compare changes in maxillary anterior alveolar bone remodeling and complication rates in adult patients with different periodontal conditions after maxillary anterior tooth retraction using fixed appliances. In addition, this study analyzed potential factors affecting alveolar bone thickness in patients with periodontitis.

METHODS

A total of 55 adult patients (mean age, 23.53 ± 4.55 years) with Angle Class I or II Division 1 malocclusion with maxillary protrusion were recruited and categorized into the healthy control group (n = 23), stage I periodontitis (P-I) group (n = 17), and stage II periodontitis (P-II) group (n = 15). The maxillary anterior teeth were retracted using a fixed appliance. Cone-beam computed tomography was used to measure the thickness, height, and density of the alveolar bone in the maxillary anterior region before (T1) and after (T2) treatment. The incidences of bone dehiscence and fenestration were documented. Statistical analysis was conducted to evaluate intergroup and intragroup differences. Clinical and cephalometric data were collected to identify factors affecting the changes in alveolar bone thickness using multivariate linear regression analysis.

RESULTS

The labial alveolar bone thickness increased significantly after treatment in all groups, but no differences were observed among the groups. In contrast, the palatal alveolar bone thickness decreased, particularly in the P-I and P-II groups, at the midroot and apical levels (P <0.05). A significant decrease in alveolar bone height was observed in the P-I and P-II groups (P <0.05). The incidence of palatal bone dehiscence was higher in the P-II (84.44%) and P-I (69.61%) groups. Multivariate linear regression analyses revealed that sex, treatment duration, periodontal treatment, changes in tooth inclination, and initial thickness significantly affected palatal alveolar bone thickness changes in patients with periodontitis.

CONCLUSIONS

After retraction of the maxillary anterior teeth with a fixed appliance, the labial alveolar bone of the maxillary anterior teeth thickened, whereas the palatal bone exhibited thinning in adults with periodontitis. The reduction in palatal bone height was more significant in this population than in healthy subjects, along with a higher incidence of palatal bone dehiscence. Bone morphology must be carefully assessed, considering these relevant factors before and during orthodontic treatment.

Comparative evaluation of alveolar bone remodeling and root length changes in fixed appliances versus clear aligners: A retrospective cohort study on skeletal Class III malocclusion treatment

BACKGROUND

The retrospective study examined changes in the root length and alveolar bone surrounding maxillary incisors in patients with skeletal Class III malocclusion treated by surgical orthodontic treatment with either fixed appliances (FAs) or clear aligners (CAs).

METHODS

A total of 60 subjects were divided based on appliance type used. Cone beam computed tomography scans were taken at three stages: before treatment, after presurgical orthodontic treatment, and post-treatment for both groups. Vertical alveolar bone level and horizontal alveolar bone thickness (ABT) were measured at four heights (3, 6, and 9 mm from the cementoenamel junction, and the root apex), along with root length, at these time points.

RESULTS

Both groups showed a decrease in root length, with the CA group experiencing a significantly smaller reduction (0.4 ± 0.79 mm) compared with the FA group (0.64 ± 0.8 mm; P = 0.02). The FA group demonstrated more significant reduction in palatal ABT (P < 0.05) and greater root resorption, whereas the CA group exhibited considerable labial marginal bone resorption (P = 0.007) and a notable decrease in labiolingual inclination (P = 0.042).

CONCLUSIONS

The findings suggest that FA and CA might lead to decreased ABT and significant root resorption, with FA therapy likely resulting in more pronounced effects. Both modalities led to notable vertical bone loss, particularly, on the labial side of the maxillary incisors in the CA group during postsurgical orthodontic treatment. Preventing iatrogenic deterioration of periodontal support surrounding the incisors is crucial during presurgical and postsurgical phases.

Comparative evaluation of periodontally accelerated osteogenic orthodontics (PAOO) versus traditional camouflage orthodontic treatment in adult patients with skeletal class III malocclusion

BACKGROUND

Existing literature supports the efficacy of PAOO in augmenting alveolar bone volume and facilitating orthodontic tooth movement. However, there is a paucity of literature addressing its application in the treatment of adults with skeletal Class III malocclusion. This retrospective clinical study aimed to compare the clinical efficacy of camouflage orthodontic treatment combined with and without PAOO in adult patients presenting with skeletal Class III malocclusion.

METHODS

A retrospective study was performed in 38 patients with mild to moderate skeletal Class III malocclusion who underwent orthodontic treatment. Patients were divided into two cohorts: the experimental group, which underwent the PAOO procedure combined with orthodontic treatment, and the control group, which received traditional camouflage orthodontic treatment alone. Radiographic assessments, including lateral cephalograms and cone-beam computed tomography (CBCT) scans, were conducted before treatment (T0) and after treatment (T1) to evaluate changes in maxillary incisor inclination, alveolar bone thickness, and various skeletal and soft tissue parameters.

RESULTS

The experimental group exhibited a significant reduction in the axial inclination of the maxillary incisors after treatment (P < 0.05; U1-PP, -4.97 ± 5.23°). The root apex of the maxillary incisors moved labially, and the A-point moved forward. In contrast, the control group demonstrated significant proclination of the maxillary incisors (P < 0.05; U1-PP, 6.80 ± 7.89°). The ANB assessments demonstrated significant improvements (P < 0.05; 3.03 ± 1.62°), with a significant difference between groups that favored the experimental group. Nasolabial angle and G Vert-Sn increased significantly only in the experimental group (P < 0.05; Nasolabial A, 9.47 ± 12.67°; G Vert-Sn, 2.19 ± 2.56 mm). Compared with T0, labial bone thickness significantly increased in the experimental group at T1, while it decreased significantly in the control group.

CONCLUSION

The integration of PAOO with orthodontic treatment appears to enhance labial alveolar bone augmentation and facilitate the labial movement of maxillary incisor roots in patients with skeletal Class III malocclusion. Concurrently, it results in significant improvements in patients' aesthetics of both soft and hard tissue profiles.

Root resorption in clear aligner treatment detected by CBCT: a Systematic review and Meta-analysis

OBJECTIVE

The aim of this study was to evaluate the amount of external apical root resorption in patients who had undergone orthodontic treatment with clear aligners evaluated using cone beam computed tomography.

METHODS

Studies that evaluated external apical root resorption before and after comprehensive orthodontic treatment with clear aligners were assessed by performing an electronic search from 5 databases comprising PubMed, SCOPUS, EBSCO, Cochrane Library, and LILACS and manual searches in the relevant journals and the reference lists of the included studies. Database search, elimination of duplicate studies, and data extraction were performed independently by 2 authors. The quality of the included studies was assessed using the Risk of Bias in Non-randomised Studies-of Interventions and the Cochrane Collaboration's Risk of Bias Tool. Studies that reported the tooth length or volume were used for quantitative analyses.

RESULTS

Nine studies were included in the meta-analysis. The overall root length after clear aligner treatment was significantly decreased compared with the pre-treatment length using cone beam computed tomography (mean differences = -0.56 mm, 95% confidence interval [-0.73, -0.38], P < .00001). However, only the maxillary central incisors, maxillary lateral incisors, and mandibular central incisors had significant reduction in root length. The meta-analysis from 3 studies also indicated that the root volume of the upper incisors also significantly decreased (mean differences = -13.34 mm3, 95% confidence interval [-16.57, -10.10], P < .00001).

CONCLUSIONS

Current evidence suggests that clear aligners can cause minimal root resorption. The highest amount of root resorption was observed in the maxillary central incisors.

Comparison and analysis of alveolar bone structure characteristics in skeletal Class II and Class III malocclusion in the mandibular incisor region

The aim of this study was to explore the differences in alveolar bone structure characteristics in skeletal class II and class III malocclusion in the mandibular incisor region. From January 2021 to November 2023, 100 cases of skeletal malocclusion patients were selected from our hospital, including 56 cases of skeletal Class II malocclusion and 44 cases of skeletal Class III malocclusion. The alveolar bone structure characteristics in the mandibular incisor region of skeletal class II and class III malocclusion patients are compared. The labial alveolar bone attachment height and lingual alveolar bone attachment height were compared between patients with skeletal Class II and Class III malocclusion (P < .05). The labial alveolar bone thickness at the root apex in patients with skeletal Class II malocclusion was (3.96 ± 0.63) mm, which was higher than that in Class III malocclusion patients (P < .05). In patients with skeletal Class II malocclusion, the cementoenamel junction was 2, 4, 6 mm below, and at the root apex, the alveolar bone thickness was (0.19 ± 0.05) mm, (0.93 ± 0.10) mm, (2.10 ± 0.10) mm, and (12.26 ± 2.10) mm, respectively, which was higher than that in Class III malocclusion patients (P < .05). In patients with skeletal Class II malocclusion, the labial side alveolar bone area at the root apex was (3.89 ± 0.72) mm2, which was higher than in Class III malocclusion patients (P < .05). On the lingual side, the alveolar bone thickness below cementoenamel junction at 6 mm and at the root apex was (1.95 ± 0.45) mm2 and (1.92 ± 0.51) mm2, respectively, which were higher than in Class III malocclusion patients (P < .05). Compared to skeletal Class II malocclusion, in skeletal Class III malocclusion, the alveolar bone thickness in the mandibular incisor area is thinner and narrower. This should be given special attention during orthodontic treatment.

Comparative assessment of external apical root resorption between subjects treated with clear aligners and fixed orthodontic appliances: A systematic review and meta-analysis

This review aims to collate and analyze the existing evidence on the comparison of external apical root resorption (EARR) in subjects treated with clear aligners (CAs) and fixed appliances (FA). An electronic search was conducted in six databases for articles published in all languages until July 2023. Studies that evaluated EARR in subjects treated with CAs and FAs were included. The RoB 2 tool for RCTs and the ROBINS-I tool for non-randomized studies were used to analyze the risk of bias (ROB). A random effects meta-analysis was performed to assess EARR extent in maxillary and mandibular anterior teeth for subjects treated with CAs and FAs. Ten studies (eight retrospective, one RCT, and one CCT) were included in this review, out of which six studies reported a moderate ROB, one reported a serious ROB, and three reported a low ROB on qualitative analysis. The quantitative analysis of six studies revealed a significant intergroup difference (P<0.05) in the mean EARR for maxillary central (SMD=-0.62, P<0.00001) and lateral incisors (SMD=-0.47, P=0.01) with a moderate heterogeneity (I2=56%), as well as the mandibular central incisors (SMD=-0.27, P=0.04) with high heterogeneity (I2=79%). EARR was lower in subjects treated with CAs than FAs. A moderate quality of the available evidence suggests that EARR was less evident in subjects treated with CAs when compared with FAs.

Evaluation of Mandibular Projection in Class II Division 2 Subjects Following Orthodontic Treatment Using Clear Aligners

AIM

The purpose of this study was to evaluate the mandibular growth and/or projection following maxillary incisor proclination, overbite correction, and maxillary dentoalveolar expansion without the use of any class II mechanics, in growing class II division 2 patients treated with clear aligners.

MATERIALS AND METHODS

Before and after treatment cone-beam computed tomographic (CBCT) generated lateral and posteroanterior cephalograms of thirty-two patients with skeletal class II division 2, 16 in the treatment group and 16 in the untreated group, were reviewed to evaluate treatment-related changes. Upper incisors were proclined and protruded, as well as upper arch expansion and overbite correction were performed as part of their regular treatment. Cephalometric analysis was performed to evaluate skeletal and dental changes. Unpaired statistical t-tests were performed to determine if significant skeletal class II correction was achieved in the treatment group.

RESULTS

In the treatment group, after treatment, the upper incisors became more proclined and protruded, and the inter-molar width increased while the overbite was reduced compared to the control group. An increase in skeletal mandibular growth and forward projection was also observed, thus contributing to an improvement of the sagittal skeletal relationship as evidenced by ANB and Wits values compared to the control group.

CONCLUSION

A combination of upper incisor proclination, correction of deep overbite, and maxillary dentoalveolar expansion using clear aligners appears to contribute to an improvement of the skeletal class II relationship in growing patients with class II division 2.

CLINICAL SIGNIFICANCE

This study shows that unlocking the mandible by correcting a deep overbite, proclining upper incisors, and expanding the upper arch in growing class II division 2 patients can improve skeletal class II using clear aligners. How to cite this article: Mirzasoleiman P, El-Bialy T, Wiltshire WA, et al. Evaluation of Mandibular Projection in Class II Division 2 Subjects Following Orthodontic Treatment Using Clear Aligners. J Contemp Dent Pract 2024;25(4):295-302.

Treatment effects after maxillary expansion using tooth-borne vs tissue-borne miniscrew-assisted rapid palatal expansion appliance

INTRODUCTION

The study investigated the skeletal effects and root resorption in young adults with maxillary transverse deficiency after tissue-borne or tooth-borne mini-implant anchorage maxillary expansion.

METHODS

Ninety-one young adults with maxillary transverse deficiency, aged 16-25 years, were divided into 3 groups according to the treatment method: group A (n = 29) comprising patients treated with tissue-borne miniscrew-assisted rapid palatal expansion (MARPE), the group B (n = 32) comprising patients treated with tooth-borne MARPE, and the control group (n = 30) comprising patients only treated with fixed orthodontic therapies. Pretreatment and posttreatment cone-beam computed tomography images were used to assess the change of maxillary width, nasal width, first molar torque and root volume by paired t test in the 3 groups, respectively. Analysis of variance and Tukey least significant difference analysis were used to detect the changes of all descriptions among the 3 groups P <0.05.

RESULTS

In the 2 experimental groups, we observed significant increases in the width of the maxilla, nasal, and arch width, as well as the molar torque. In addition, the height of the alveolar bone and the root volume decreased significantly. There were no significant differences in the maxilla, nasal, and arch width change between the 2 groups. Group B displayed more increases in buccal tipping, alveolar bone loss, and root volume loss than group A (P <0.05). Compared with groups A and B, the control group showed negligible tooth volume loss, with no expansion effect in both skeletal and dental descriptions.

CONCLUSIONS

Tissue-borne MARPE produced the same expansion efficiency as tooth-borne MARPE. However, tooth-borne MARPE causes more dentoalveolar side effects in buccal tipping, root resorption and alveolar bone loss.

Asymmetric Extraction Treatment in a Middle-Aged Patient with Dental Crowding and Protrusion using Clear Aligners

Frequently, orthodontic treatment involves symmetrically extracting premolars to correct severe crowding or protrusion. Nevertheless, in some cases, a more reasonable alternative may be to remove teeth with poor prognoses to improve protrusion and relieve crowding. A middle-aged woman sought treatment for dental protrusion and crowding. Her mandibular right first molar had been treated with root canal therapy due to pulpitis, but she still felt uncomfortable. In addition, her maxillary left second premolar had become carious. Extractions of the maxillary right first premolar and left second premolar, as well as mandibular right first molar and left first premolar were chosen to resolve the occlusion problems. The patient opted for clear aligners on the demands of esthetics as well as comfort. Following orthodontic treatment, the patient attained properly aligned teeth, a pleasing smile, and a facial profile that exhibited greater harmony. This case report demonstrates that, under proper planning, clear aligners are capable of handling challenging cases, including those involving middle-aged individuals and molar extractions.

[Comparison of the outcome of orthodontic dental movement using aligners versus fixed orthodontics: a review]

Introduction

The aligners have become a preferred alternative in terms of orthodontic treatment, surpassing the choice of conventional brackets, due to the comfort and aesthetics that the aligners represent, however, the final result with this system continues to be a controversial issue. The objective of this review was to verify the effectiveness of the treatment completed with aligners versus conventional brackets.

Materials and methods

An exhaustive search was carried out in the PubMed, ScienceDirect, Scopus and Embase databases up to the date of January 5, 2023, including comparative studies that evaluated the final result and treatment time of the aligners compared to conventional braces. Two researchers carefully selected the articles evaluated and analyzed different key topics on the subject.

Results

In this study, 8 articles were included, according to the studies, the vast majority did not find significant differences in completion between the compared groups. In addition to this, the treatment time in 3 articles was faster with aligners, in 3 articles it was faster with conventional brackets, and in one article no significant difference was found, so it is not yet established whether a system is faster than the other.

Conclusions

Both aligners and conventional fixed orthodontics had good results at the end of orthodontic treatment and presented a similar treatment time, however, the majority of treated cases belonged to malocclusions of medium to low complexity, so these cannot be generalized. findings to all malocclusions.