Influence of Invisalign precision bite ramp utilization on deep bite correction and root length in adults.

OBJECTIVES: To assess the influence of Invisalign precision bite ramp use on skeletal deep overbite correction and root length and volume of maxillary anterior teeth. MATERIALS AND METHODS: This was a retrospective study of 60 adults with skeletal deep overbite. Patients were divided into three groups: Invisalign (Align Technology, San Jose, Calif) with precision bite ramps (Invisalign with Bite Ramps [IBR] = 12), Invisalign with no bite ramps (INBR = 22), and full-fixed appliances (FFA = 26). Cone beam computed tomography records at T1 (pretreatment) and T2 (posttreatment) were used to measure eight skeletal, nine dental, and three soft-tissue cephalometric variables. Maxillary anterior teeth root length (mm), root volume (mm3), and percent root volume loss between T1 and T2 (%) were also recorded. RESULTS: Significant changes from T1 to T2 among the three groups were seen in ANB(o), lower face height (%), ODI (overbite depth indicator) (o), and U1-SN (o). Reduction in root length was significantly less (P < .001) in the INBR and IBR groups compared to the FFA group. Reduction in root volume and percent volume loss were significantly higher in the INBR group compared to the IBR group (P < .001), but the difference between the two Invisalign groups and the FFA group was not significant. CONCLUSIONS: Skeletal deep overbite correction using Invisalign with or without bite ramps is comparable to FFA. Reduction in root length was significantly less with Invisalign compared to FFA. Bite ramps influenced root volume and volume loss but not root length.

Effectiveness of removable anterior bite planes with varied mealtime protocols in correcting deep bites among growing patients: a randomized clinical trial.

OBJECTIVES: To compare effectiveness of two protocols for correcting deep bite in growing patients using a removable anterior bite plane (RABP): full-time wear with appliance on during meals (F + M) vs off during meals (F - M) and to explore the relationship between average daily duration of wear and overbite (OB) correction rate, stratified by the wear protocol. MATERIALS AND METHODS: Thirty-two growing patients with deep bite (mean age = 10.94 ± 2.17 years) were randomly assigned to the F + M (n = 16) or F - M (n = 16) group. Cephalometric radiographs were taken at baseline (T0) and when normal OB was achieved (T1). Duration of wear was recorded by a TheraMon microsensor within the appliance. A best-fit regression model for the relationship between daily duration of wear and OB correction rate was determined (α = 0.05). RESULTS: Both groups exhibited similar baseline characteristics and cephalometric changes, ie, molar extrusion, and incisor intrusion and proclination in both arches (P < .05), and intergroup differences were not significant. Here, F + M exhibited significantly faster rates of deep bite correction (1.83 ± 1.18 vs 1.08 ± 0.62 mm/month; P < .05) and mandibular molar extrusion (0.46 ± 0.25 vs 0.30 ± 0.18 mm/month, P < .05) compared with F - M. Best-fit regression models for relationship between daily duration of wear and OB correction rate were exponential for both F + M (R2 = 0.53) and F - M (R2 = 0.74). CONCLUSIONS: Here, F + M and F - M protocols resulted in comparable cephalometric changes among deep bite growing patients. However, the F + M group exhibited a faster correction rate. Daily duration of wear positively correlated with OB correction rate in an exponential manner.

Evaluation of the Best Method for Orthodontic Correction of Skeletal Deep Bites in Growing Patients: A Systematic Review.

This review aimed to evaluate the currently available evidence regarding the best method of correcting deep bites in growing patients. In September 2023, a search was conducted electronically across the following databases: PubMed®, Web of Science™, Scopus®, Embase®, Google™ Scholar, and Cochrane Library. In this systematic review, randomized control trials (RCTs), controlled clinical trials (CCTs), and cohort studies of growing patients with deep bite malocclusion who received treatment with the primary objective of treating the deep bite were included. Risk of bias of the included studies was assessed using two different tools; one tool was applied for RCTs and the other one for the CCTs and cohort studies. One RCT, one CCT, and one cohort study were included (85 patients). The flat fixed acrylic bite plane was superior in terms of duration of treatment when compared to the inclined fixed acrylic bite plane and the utility arch with posterior intermaxillary elastics. Limited evidence indicates that the inclined fixed acrylic bite plane causes a significant increase in the lower incisor inclination and a significant increase in the angle between the mandible and the anterior cranial base (SNB). However, limited evidence indicates that the utility arch with posterior intermaxillary elastics causes a significant decrease in the angle between the maxilla and the anterior cranial base (SNA). Regarding the vertical skeletal changes, it was found that the three methods were comparable; in each case, the vertical dimension of the face increased because of a significant increase in the lower first molar height. There is a need for further studies to strengthen the evidence of the treatment efficacy of the employed methods, with more RCTs to be conducted in this regard.

Does aligner refinement have the same efficiency in deep bite correction?: A retrospective study.

BACKGROUND: Refinements are very common in clear aligner treatments. The aim of this study is to assess whether the predictability of deep overbite correction is similar over several refinements using clear aligners (Invisalign, Align Technology, San Jose, Calif) and examine the accuracy of vertical movement and inclination change of individual teeth. METHODS: This retrospective study included 20 deep bite patients (7M and 13F; 32.63 ± 11.88 years old; an initial overbite of 5.09 ± 0.98 mm), consecutively treated from September 2016 and March 2023, who completed at least two sets of aligners, including refinements. The initial, predicted, and achieved models were exported from ClinCheck or OrthoCAD (Cadent Inc, Carlstadt, NJ) and superimposed via best-fit surface-based registration using SlicerCMF (version 4.9.0; cmf.slicer.org). We also examined 15 out of 20 patients who completed treatments. The overbite correction and changes in vertical movement and inclination for individual teeth were measured. Descriptive statistics and a paired t-test or Wilcoxon signed-rank test were performed. P < 0.05 was considered statistically significant. RESULTS: The mean accuracy of overbite correction was 37.63% after 1st set, followed by 11.19%, 6.32%, and 13.80% (2nd-4th sets), respectively. There were statistically significant differences between the predicted and achieved vertical movements and inclination changes for all teeth for the 1st and 2nd sets. For the completed cases, the mean overbite correction was 38.54% compared to the initially planned overbite correction, which is similar to one of the 1st set. Still, the vertical movements and inclination changes of all teeth present statistically significant differences between the initially planned and finally achieved movements except for maxillary lateral incisor torque. CONCLUSIONS: The most overbite correction occurs during the 1st set of aligners, and refinement treatment does not significantly improve the deep bite correction.

Biomechanical and clinical considerations in deep bite treatment using temporary skeletal anchorage devices.

Deep bite is usually treated by intrusion of the anterior teeth, extrusion of the posterior teeth, or a combination thereof. Various traditional methods have been used to correct deep bites, but they can cause negative side effects. Recently, temporary skeletal anchorage devices (TSADs) have been used to intrude the anterior teeth simply and efficiently without side effects. The amount of incisal exposure at rest should be considered as the first factor in determining which tooth segment should be intruded to correct a deep bite. The center of resistance of the anterior teeth should be considered to achieve the proper biomechanics when intruding them. The location of TSADs should be determined to ensure sufficient interradicular bone to achieve the desired tooth movement. Therefore, clinicians should understand the biomechanical and clinical considerations to correct a deep bite using TSADs.

Comprehensive Deciphering the Complexity of the Deep Bite: Insight from Animal Model to Human Subjects.

Deep bite is a malocclusion phenotype, defined as the misalignment in the vertical dimension of teeth and jaws and characterized by excessive overlap of the upper front teeth over the lower front teeth. Numerous factors, including genetics, environmental factors, and behavioral ones, might contribute to deep bite. In this study, we discuss the current clinical treatment strategies for deep bite, summarize the already published findings of genetic analysis associated with this complex phenotype, and their constraints. Finally, we propose a comprehensive roadmap to facilitate investigations for determining the genetic bases of this complex phenotype development. Initially, human deep bite phenotype, genetics of human deep bite, the prevalence of human deep bite, diagnosis, and treatment of human deep bite were the search terms for published publications. Here, we discuss these findings and their limitations and our view on future strategies for studying the genetic bases of this complex phenotype. New preventative and treatment methods for this widespread dental issue can be developed with the help of an understanding of the genetic and epigenetic variables that influence malocclusion. Additionally, malocclusion treatment may benefit from technological developments like 3D printing and computer-aided design and manufacture (CAD/CAM). These technologies enable the development of personalized surgical and orthodontic guidelines, enhancing the accuracy and effectiveness of treatment. Overall, the most significant results for the patient can only be achieved with a customized treatment plan created by an experienced orthodontic professional. To design a plan that meets the patient's specific requirements and expectations, open communication between the patient and the orthodontist is essential. Here, we propose to conduct a genome-wide association study (GWAS), RNAseq analysis, integrating GWAS and expression quantitative trait loci (eQTL), micro and small RNA, and long noncoding RNA analysis in tissues associated with deep bite malocclusion in human, and complement it by the same approaches in the collaborative cross (CC) mouse model which offer a novel platform for identifying genetic factors as a cause of deep bite in mice, and subsequently can then be translated to humans. An additional direct outcome of this study is discovering novel genetic elements to advance our knowledge of how this malocclusion phenotype develops and open the venue for early identification of patients carrying the susceptible genetic factors so that we can offer early prevention and treatment strategies, a step towards applying a personalized medicine approach.

Cephalometric evaluation of deep overbite correction using anterior bite turbos.

OBJECTIVES: To evaluate the outcome of treating deep overbite (OB) using anterior bite elevators concurrently with a pre-adjusted edgewise appliance. MATERIALS AND METHODS: The Case Western Reserve University (CWRU) cephalometric analysis was used to isolate tipping movement of upper (TUI) and lower incisors (TLI), bodily tooth movement of upper (BUI), and lower incisors (BLI), as well as vertical skeletal changes in the anterior region of the maxilla (MXSK) and mandible (MNSK). Thirty treated subjects were examined at pretreatment (T1) and posttreatment (T2) and compared to an untreated control group matched on age, sex, and Angle malocclusion from the Bolton Brush Growth Study Collection (CWRU, Cleveland, Ohio). RESULTS: Overbite (OB) in the treated group was decreased significantly (P < .001) (-5.6 mm) compared to controls. Statistically significant (P < .001) changes were found for BUI (-0.7 mm), TUI (0.9 mm), TLI (-1.4 mm), BLI (-1.1 mm), and MNSK (-1.6 mm). Most of the overbite correction was in the lower arch and included tipping and intrusion of the lower incisors along with an increase in lower vertical facial height. CONCLUSIONS: Deep OB correction was achieved efficiently using anterior bite elevators with pre-adjusted edgewise appliance. Correction using bite turbos would be a treatment option for individuals presenting with decreased lower facial height and deep bite.

The Effects of Intrusion of Anterior Teeth by Skeletal Anchorage in Deep Bite Patients; A Systematic Review and Meta-Analysis.

BACKGROUND: Deep bite is known as one of the most common malocclusions, and its treatment and retention are often challenging. The use of mini-screws has been suggested as an ideal method for the intrusion of incisors in deep-bite patients. Still, there are conflicting reports regarding the superiority of this method compared to other common treatments. AIM: The aim of this systematic review and meta-analysis was to evaluate the effects of the intrusion of anterior teeth by skeletal anchorage in deep bite patients. METHODS: From the beginning to 15 September 2022, articles on the topic of interest were searched in electronic databases including PubMed, Web of Science, Scopus, EMBASE, and Cochrane's CENTRAL. Additionally, a hand search for pertinent studies and a search of the grey literature were carried out. After the selection of eligible studies, data extraction was performed using piloted forms. Inverse-variance random-effects meta-analyses were used to combine the outcome measures of dental indices, skeletal cephalometric indices, and dental cephalometric indices. RESULTS: A total of 15 studies (6 RCT; 9 CCT) were included in the systematic review and 14 were used in the meta-analyses. The differences in overbite changes (MD = -0.45, p = 0.04), true incisor intrusion [u1-pp] (MD = -0.62, p = 0.003) and molar extrusion [u6-pp] (MD = -0.40, p = 0.01) were statistically significant and TADs showed better treatment results than other intrusion methods (segmented intrusion arch, utility arch, J hook headgear). No significant differences regarding overjet, molar and incisor tipping, and skeletal indices between mini-screw and other intrusion methods could be found. CONCLUSION: The use of mini-screws leads to lower overbite and higher true intrusion (about 0.45 and 0.62 mm, respectively) compared to the use of other methods for intruding upper incisors. Furthermore, the effect of TAD on extrusion of molar teeth is less (by 0.4 mm) than other methods.

Evaluation of efficacy of utility arch with inter-maxillary elastics for treating skeletal deep bite with retroclined upper incisors in the mixed dentition: a clinical randomized controlled trial.

OBJECTIVES: To investigate the effectiveness of utility arch (UA) with inter-maxillary elastics compared with fixed anterior bite plane (FABP) for treating deep bite in brachy-facial children. MATERIALS AND METHODS: This was a single-center, randomized controlled trial. Participants were children aged between 9 and 12 years with deep bite and a hypodivergent skeletal pattern. The sample was divided into the following two groups: (1) a UA group that was composed of patients with UAs with posterior inter-maxillary elastics and (2) an FABP group as a control. Outcomes were skeletal and dentoalveolar variables on cephalometric X-rays. RESULTS: A total of 28 patients (13 boys, 15 girls) with a mean age of 10.66 years were enrolled. The treatment duration was 8.16 months in the UA group and 7.22 months in the FABP group. After treatment, the angle between the anterior cranial base and the mandible in the vertical plane increased significantly (P = .000) in both groups (about 1.97 degrees in the UA group and 2.75 degrees in the FABP group). Overbite decreased significantly in both groups (-2.1 m in the UA group and -3.64 m in the FABP group), but it decreased less significantly in the UA group than in the FABP group. The upper incisors flared significantly after treatment with both appliances (6.6 degrees in the UA group and 5.9 degrees in the FABP group). CONCLUSIONS: Treatment of deep bite in children with a horizontal growth pattern by each of the appliances used in this study is effective. The mandible showed minor, significant backward rotation after treatment. The overbite decreased less in the UA group than in the FABP group.

Investigating the Effectiveness of Low-Level Laser in Reducing Root Resorption of the Upper Incisors During Intrusion Movement Using Mini-Implants in Adult Patients With Deep Overbite: A Randomized Controlled Clinical Trial.

BACKGROUND: Deep bite is a common characteristic of malocclusion, and many methods are used to treat it, including mini-implants used for the intrusion of the upper incisors. Orthodontically induced inflammatory root resorption (OIIRR) is an inevitable and unexpected side effect of orthodontic therapy. However, resorption of the root could be affected by the type of tooth movement, such as intrusion. Several studies have indicated the effectiveness of low-level laser therapy (LLLT) in accelerating orthodontic movement, but studies that have evaluated the role of this laser in reducing the risk of OIIRR have been limited. This trial aimed to investigate the effectiveness of LLLT in reducing the resorption of the roots of the upper incisors during their intrusion in the context of deep bite correction. MATERIALS AND METHODS: Thirty patients (13 males, 17 females; mean age 22.4±3.37 years) with deep overbite were recruited and allocated to the laser or the control groups. Mini-implants were inserted between the roots of the upper central incisors and the lateral incisors from the labial aspect at the gingival-mucosal junction on both sides with a force of 40 g on each side through an NiTi coil spring. A low-level laser (Ga-Al-As) with 808 nm wavelength in a continuous mode, with the parameters 250 milliwatt power output, 4 Joules/point energy density, and 16 seconds irradiation per point, was applied to the root of each of the upper incisors. The laser was applied on the first day of the upper incisor intrusion (T1), then on days 3, 7, and 14 of the first month. In the second month, the laser was applied every 15 days, adjusting the spring strength every four weeks until the end of the intrusion stage (T2), which was determined by reaching a normal overbite. As for patients in the control group, the strength of the nickel-titanium springs was adjusted every four weeks to the required strength of 40 g on each end until reaching a normal overbite. RESULTS: There was a volumetric decrease in both groups' upper central and lateral incisors roots, and this decrease was statistically significant (P<0.001). However, the difference between the two groups was not statistically significant in each central and lateral incisor volume root (P=0.345 and 0.263 for U1 and U2, respectively). Also, both groups had a linear decrease in upper central and lateral incisors roots, which was statistically significant (P<0.001). At the same time, the difference between the two groups was not statistically significant in each central and lateral incisor root length (P=0.343 and 0.461 for U1 and U2, respectively). CONCLUSION: The low-level laser irradiation using the current protocol did not significantly affect the amount of root resorption induced by incisor intrusion in the experimental group compared to the control group.

Overbite recognition and factors affecting esthetic tolerance among laypeople.

OBJECTIVES: To determine recognition ability and the levels of esthetic tolerance of deep bite and anterior open bite (AOB) among laypeople and investigate the factors affecting levels of tolerance. MATERIALS AND METHODS: Using a questionnaire, laypeople (N = 100) were examined, and overbite was measured. They were tested for whether they recognized deep bite and AOB. Esthetic tolerance thresholds for deep bite and AOB were selected by incremental depiction in grayscale images. Stepwise logistic regression analyses were used to quantify the effect of recognition and other factors (age, sex, education level, occupation, history of orthodontic treatment, interest in orthodontic treatment or retreatment, and overbite presence) affecting the tolerance of overbite problems (α = 0.05). RESULTS: Of the participants, 55% and 94% recognized deep bite and AOB, respectively. Participants with a deep bite were significantly more likely to esthetically tolerate deep bite compared with those without a deep bite (odds ratio [OR], 3.57; 95% confidence interval [CI], 1.29-9.89). Participants who recognized a deep bite problem had significantly lower esthetic tolerance to deep bite compared with participants who did not recognize a deep bite (OR, 0.17; 95% CI, 0.06-0.45). None of the other eight chosen factors significantly affected the tolerance level of AOB (P > .05). CONCLUSIONS: Participants with a deep bite or those who did not recognize a deep bite had significantly higher esthetic tolerance of deep bite than those without or those who recognized the problem (P < .05).

Orthodontic correction of Class II skeletal malocclusion complicated by deep bite using clear aligners: A case report.

This case report describes an orthodontic treatment using clear aligners in a patient with Class II malocclusion associated with a deep bite. A 16-year-old patient with skeletal Class II malocclusion presented with a retrognathic profile, a deep bite of 7 mm, deep curve of Spee, proclined incisors, spacing, an excess Bolton discrepancy in the mandible, lower midline shift 2 mm to the right, and long clinical crowns. The patient preferred aligners over traditional fixed orthodontic appliances. The treatment objectives were achieved in 2.2 years, and the patient was pleased with the aesthetic and treatment outcomes. Using aligners along with proper auxiliaries and attachments is an effective method of addressing orthodontic difficulties, such as Class II complicated with deep bites in a reasonable time. Further, clear aligners offer less pain, better oral hygiene, and more aesthetics comparable to that of conventional fixed orthodontic appliances.

Mandibular incisor root volume changes between anterior bite planes fabricated from acrylic resin and thermoplastic materials: a prospective randomized clinical trial.

OBJECTIVES: To compare mandibular incisor root volume change (RVC) after 6 months between an anterior bite plane fabricated from acrylic resin (ABP) and thermoplastic materials (TBP) in a group of growing patients. MATERIALS AND METHODS: Thirty-four deep bite patients (age: 11.57 ± 1.30 years) were randomized into the ABP or TBP group. The RVC from before treatment (T0) to 6 months after treatment (Tct) at the labio-coronal (La1), labio-middle (La2), labio-apical (La3), linguo-coronal (Li1), linguo-middle (Li2), and linguo-apical (Li3) segments were investigated from cone beam computed tomography (CBCT) images. Cephalometric changes between T0 and the visit that normal overbite was achieved (Tcep) were also assessed (α = 0.05). RESULTS: Thirty-four patients completed the trial. Treatment duration was 5.0 ± 2.9 months. Significant decrease in root volume (RV) was found at the La2, La3, and Li3 segments of the ABP group (P < .05). No significant RVC was found in any segment of the TBP group (P ≥ .05). Comparing between groups, the RVC at La3 and Li3 of the ABP group was significantly greater than that of the TBP group (P < .05). However, total RVC between groups was not significantly different (P ≥ .05). CONCLUSIONS: Growing patients undergoing deep bite correction for 6 months with ABP displayed more apical RVC of mandibular incisors than those who used TBP. However, total RVC between appliances was not significantly different.

Adjunctive use of a surgical splint for leveling the curve of Spee following mandibular advancement.

Deep curve of Spee is a very common problem among Class II malocclusion patients associated with mandibular deficiency. The curve of Spee is maintained and leveled following surgical mandibular advancement. The same surgical splint which is used to guide the mandibular advancement can also be used for the leveling of deep curve of Spee. This case report highlights the leveling of deep curve of Spee by the same surgical splint used during the surgical mandibular advancement. Thus, it helps to increase the lower facial height and also improves the overall facial appearance.

Effects of anterior bite planes fabricated from acrylic resin and thermoplastic material on masticatory muscle responses and maximum bite force in children with a deep bite: A 6-month randomised controlled trial.

BACKGROUND: Anterior bite planes are bite-raising appliances used for deep bite correction. However, muscle responses to anterior bite planes of different harnesses may vary. OBJECTIVES: To prospectively evaluate masticatory muscle activity, muscle balance and maximum bite force (MBF) responses to anterior bite planes fabricated from acrylic resin (ABP) or bi-laminate thermoplastic (TBP) over 6 months in children with a deep bite. METHODS: Sixty-six children were randomly assigned to the ABP, TBP or untreated control groups. Masticatory muscle activity, activity index (AC) and percentage overlapping coefficient (POC) were assessed by surface electromyography; MBF, using a custom-made bite force sensor. Data were collected before, immediately after appliance insertion and after 2 weeks and 1, 3 and 6 months of treatment. Within- and between-group differences were analysed using the one-way ANOVA/Kruskal-Wallis and Mann-Whitney U tests (α = .05); Friedman's tests were used to assess within-group differences over time (α = .08). RESULTS: At rest, no dependent variables changed throughout the study. At maximum clenching, masticatory muscle activity immediately dropped significantly but returned to baseline values and was equal to the control group at 1-3 months. The ABP group had significantly lower masseter activity and AC than the TBP group after insertion. Neither POC nor MBF were significantly different within or between groups. CONCLUSION: Masticatory muscle activity reduced after anterior bite plane insertion but returned to baseline after 1-3 months. Masseter activity decreased significantly more in the ABP group than TBP group. Neither appliance significantly affected POC or MBF. CLINICAL TRIAL REGISTRATION: Thai Clinical Trial Registry (TCTR20210330002).

Chewing Patterns and Muscular Activation in Deep Bite Malocclusion.

BACKGROUND: Deep bite, a frequent malocclusion with a high relapse rate, is associated with craniofacial features that need to be considered in the course of orthodontic treatment. METHODS: This study included 81 patients with deep bite malocclusion (11.4 ± 1.1 [yr.mo]; M = 32 and F = 49), and 14 age- and gender-matched controls (9.11 ± 1 [yr.mo]; M = 5 and F = 9). The patients with deep bite malocclusion were treated with functional therapy. The chewing cycles and masticatory muscle EMG activity were recorded concomitantly before treatment in both groups (n = 95). Following correction of the malocclusion, a second recording took place (n = 25). RESULTS: The kinematic variables showed the same dependency on bolus hardness in those with deep bite and in the controls. The masticatory muscle EMG activity was increased in those with deep bite, but decreased as a result of functional treatment. The chewing patterns showed a tendency towards a reduced lateral component, which significantly increased after treatment, indicating that functional therapy impacts the neuromuscular coordination of mastication, as well as dental positioning. CONCLUSIONS: Deep bite is a complex malocclusion, involving alterations in chewing and masticatory muscle activity. Orthognathodontic treatment should not only consider and correct the teeth position, but should also address muscular hyperactivity.

Traumatogenic Occlusion in a Pediatric Dental Patient: A Case Report.

Aim and objective: This case report aims to describe the management of mandibular anterior teeth subjected to occlusal trauma. Background: Occlusal trauma occurs as a result of reduced ability of the tissues to resist the occlusal forces most likely as a result of masticatory system dysfunction abnormal contact of the teeth, and prosthetic or orthodontic treatments that create occlusal interferences. Case description: This paper describes a case of traumatogenic occlusion seen in the dentition of a 13-year-old female patient and its management by stabilization, endodontic, and orthodontic therapy. Conclusion: The removal of the anomalous occlusal forces and stabilization of the affected teeth is the most relevant therapy for teeth affected by trauma from occlusion (TFO). Clinical Significance: Periodic monitoring of developing occlusion contributes to preventive care and encourages the maintenance of a healthy periodontium. How to cite this article: Kartha S, Vellore KP, Challa SK, et al. Traumatogenic Occlusion in a Pediatric Dental Patient: A Case Report. Int J Clin Pediatr Dent 2022;15(2):222-226.

Orthodontic brackets debonding: evaluation of the time factor and the tooth type / Décollement des attaches orthodontiques : évaluation du facteur temps et du type de dent

Introduction: The aim of the study was to assess the time factor and tooth type during premature debond of orthodontic brackets. Material and Method: A retrospective epidemiological study was carried out on adolescents who had benefited from a multi-metal vestibular attachment treatment, having all 6 to 6 teeth bonded to the arch on the day of installation. Results: 333 patients were included. The detachment rate decreased as the treatment progresses. The teeth with most orthodontic debonding were the maxillary first molar, mandibular first molar, mandibular second premolar, and maxillary second premolar. Skeletal class II patients tended to take off more than class I patients. Detachments were significantly more frequent in the mandibular arch in deepbite compared to normalbite patterns, the mandibular second premolar being the tooth at risk. There seems to be a correlation between the quality of oral hygiene and the rate of detachment, regardless of the time of treatment. Discussion: The type of orthodontic movement, the quality of the bonding, the failure to observe the precautions by the patient may affect the date of the detachment. The low coronary height, hygiene, the biting force, the divergence seems to intervene on the type of attachment debonded. Conclusion: The brackets are more particularly debonded at the start of treatment and on the posterior teeth. Anteroposterior and especially vertical dysmorphosis could have an implication in debonding.

Introduction: L'objectif de l'étude était d'évaluer le facteur temps et le type de dent lors du décollement prématuré des attaches orthodontiques. Matériel et méthode: Une étude épidémiologique rétrospective a été réalisée sur les adolescents ayant bénéficié d'un traitement multi-attache vestibulaire en métal, ayant toutes les dents collées de 6 à 6 sur arcade le jour de la pose. Résultats: Au total, 333 patients ont été inclus. Le taux de décollement diminuait au fur et à mesure du traitement. Les dents avec le plus de décollements d'attaches orthodontiques étaient la première molaire maxillaire, la première molaire mandibulaire, la deuxième prémolaire mandibulaire et la deuxième prémolaire maxillaire. Les patients en classe II squelettique ont tendance à davantage décoller que les patients en classe I. Les décollements étaient significativement plus fréquents à l'arcade mandibulaire chez les hypodivergents que chez les mésodivergents, la deuxième prémolaire mandibulaire étant la dent à risque. Il semble exister une corrélation entre la qualité de l'hygiène buccale et le taux de décollement, quel que soit le moment du traitement. Discussion: Le type de déplacement orthodontique, la qualité du collage, le défaut d'observance des précautions par le patient peuvent intervenir sur la date de décollement. La hauteur coronaire faible, l'hygiène, la force de morsure, la divergence semblent intervenir sur le type d'attache décollé. Conclusion: Les attaches sont plus particulièrement décollées en début de traitement et sur les dents postérieures. Les dysmorphoses antéro-postérieures et surtout verticales pourraient avoir une implication dans le décollement.

Sagittal Positional Changes of the Mandible Following Alignment and Levelling of Class II Division 2 Cases: An Observational Study in Decelerating Stages of Adolescent Growth Spurt.

Introduction The objective of this observational study is to compare the dental and skeletal changes that occur following the release of incisor locking in class II division 2 patients in the decelerating phase of the adolescent growth spurt. Materials and methods Lateral cephalograms of 17 subjects with skeletal class II and division 2 malocclusion, taken at the pre-treatment (T1) and post-leveling and alignment (T2) phases, were analyzed. All these patients were treated with non-extraction methods in the initial stage. A total of 25 skeletal and dental parameters, which included linear and angular measurements, were evaluated. Statistical analysis A paired t-test was used to compare the difference in the dimensional values between (T1) and (T2) points of the time period. The results were considered statistically significant at Bonferroni adjusted p<0.002. Results A statistically significant positional change was noted in the condylar position both in the vertical and sagittal directions, resulting in sagittal changes of the mandible in the forward direction. The deep bite was relieved by vertical changes in the dental structures in both the posterior and anterior segments. Growth changes in the vertical direction were also noted but not conclusive. Conclusions There was a definite horizontal shift of the mandible, improving maxillo-mandibular relations following the unlocking of the bite in class II division 2 patients. This shift is mostly attributed to the condylar repositioning in the forward and downward directions.

Comparing the Effect of Miniscrew-Supported and Conventional Maxillary Incisor Intrusion on the Inclination of Maxillary Incisors and Molars - A Systematic Review and Meta-Analysis.

Objective: The objective of this study was to compare the effect of miniscrew-supported maxillary incisor intrusion and conventional intrusion mechanics on maxillary incisors and molar inclination. Material and Methods: Search databases (PubMed, Scopus, Web of Science, Embase, EBSCOhost, and the Cochrane Library) were searched for randomized trials on intrusion of maxillary incisors via miniscrew-supported and conventional mechanics. The revised Cochrane risk-of-bias tool for randomized trials (RoB 2.0) was used. Five outcomes ([i] inclination change of upper incisors, [ii] inclination change of upper molars, [iii] intrusion of incisors, [iv] vertical change in upper first molars, and [v] overbite correction achieved) were statistically pooled using Review Manager 5.3. Subgroup analysis was conducted to receive sturdiness in meta-analysis. The quality of evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation. Results: Out of 1777 studies, 7 were finally subjected to quality assessment, and 6 were included in the meta-analysis. The incisor inclination following maxillary incisor intrusion increased in miniscrew-supported intrusion in comparison to Connecticut intrusion arch (CTA) subgroup with standard mean difference of 0.66 mm (95% confidence interval = 0.16, 1.03, I2 = 0%). All the included studies showed an increase in molar inclination (distal tipping) in the CTA subgroup compared to the micro-implant group. Of all the seven included studies, only one study was identified with some concerns for the risk of bias, and the other six were judged to have an overall high risk of bias. Conclusion: The incisal proclination during deep-bite correction by miniscrew-supported incisal intrusion is more than that in the CTA subgroup; however, the difference may not be clinically very relevant. There is a very low quality of evidence in favor of miniscrew-supported intrusion as compared to conventional intrusion, necessitating the need for good-quality trials.