Overjet Reduction Research Articles

A Comparative Study of Traditional and Computer-aided Surgical Simulation Guides in Orthognathic Correction of Bimaxillary Protrusion.

To compare the efficacy of traditional occlusal guides with computer-aided surgical simulation (CASS) guides in enhancing postoperative outcomes for patients with bimaxillary protrusion. This retrospective study evaluated 34 patients undergoing anterior maxillary and mandibular subapical osteotomy at the Plastic Surgery Hospital of the Chinese Academy of Medical Sciences. Fourteen patients were treated using traditional occlusal guides, whereas 20 patients were treated with CASS guides (median age 28.6 years, median follow-up 259 days). Pre and postoperative cephalometric indicators were measured using cephalometric software. Data analysis was conducted using SPSS 14.0, with significant differences determined at P < 0.05. All 34 patients experienced primary healing without complications. Follow-up indicated significant improvements in key cephalometric measurements in the CASS group compared with the traditional group, including mandibular position (SNB angle, P < 0.001), jaw relationship (ANB angle, P < 0.001), facial angle (FH-NPo, P = 0.002), and condyle-to-sella distance (Co-S, P = 0.024). The CASS group also showed better aesthetic outcomes, with significant reductions in overjet (P = 0.012), overbite (P = 0.001), and improved alignment of upper and lower incisors (U1-L1 angle, P = 0.031). CASS-guided surgery offers a superior alternative to traditional methods for treating bimaxillary protrusion, providing more precise and aesthetically pleasing results. This study highlights the significant advantages of using advanced digital simulation and 3-dimensional printing technologies in orthognathic surgery.

Three-dimensional analysis of posttreatment tooth movements despite bonded retainers: partI-upper jaw.

Adverse side effects of fixed retainers in terms of unwanted tooth movements have been described for both the upper and lower jaw, but data about the extent and movement patterns for the maxilla are scarce. The purpose of the present retrospective case-control study was to analyze the amount and direction of unwanted tooth movements despite upper bonded retainers as well as to analyze possible predisposing pretreatment- and treatment-related factors. Plaster casts of 1026 patients who completed orthodontic treatment and asubsequent retention phase of 2years were screened for unintentional tooth movements. The study group comprised 57patients with visually obvious tooth movements in the upper jaw, while 57randomly selected patients without visible tooth movements served as control group. For all patients, plaster casts after debonding of multibracket appliance (T1) and after supervised retention (T2) were digitized, and superimposed digitally using astable palatal reference area. Thereafter, translational and rotational movements were measured in all three planes of space. Pretreatment- and treatment-related factors of the study and control groups were compared by χ2 test, exact Fisher test, Mann-Whitney U test, and the T‑test for independent samples. The mean translational movements ranged between 0 and 0.6 mm and the average rotational movements between 0 and 1.3°. Large individual movements up to 2.7 mm translation and 15.9° rotation were seen. Amovement pattern around the Y‑ and Z‑axis with an opposite rotational peak at the canines ("upper twist effect") was identified. Compared to the control group, patients of the study group showed asignificantly smaller intercanine width pretreatment. Also, study group patients presented alarger intercanine expansion and aslightly larger overjet reduction during treatment, and were more often affected by retainer bonding site detachments and wire fractures, but without reaching statistically significance. Upper bonded retainers show asimilar unwanted movement pattern ("twist effect") like the one described for mandibular retainers.

Assessing the Efficacy of Early versus Late Orthodontic Intervention in the Management of Class II Malocclusion: A Comparative Analysis

ABSTRACT Background: Class II malocclusion is a common orthodontic issue characterized by the excessive protrusion of the upper teeth relative to the lower teeth. Early intervention during mixed dentition has been advocated to guide skeletal growth and potentially reduce the severity of malocclusion. Materials and Methods: A comparative analysis was conducted to evaluate the efficacy of early (before the pubertal growth spurt) versus late (after the pubertal growth spurt) orthodontic intervention in managing Class II malocclusion. A cohort of 100 patients diagnosed with Class II malocclusion was divided into two groups: early intervention group (n = 50) and late intervention group (n = 50). Treatment outcomes including changes in overjet, molar relationship, and cephalometric measurements were assessed before and after orthodontic treatment. Results: In the early intervention group, the mean reduction in overjet was 5.2 mm (SD = 1.3), while in the late intervention group, it was 3.8 mm (SD = 1.6). The improvement in molar relationship was greater in the early intervention group (mean change = 4.5 mm, SD = 1.1) compared to the late intervention group (mean change = 3.1 mm, SD = 1.4). Cephalometric analysis revealed significant differences in skeletal and dental parameters between the two groups, with greater improvements observed in the early intervention group. Conclusion: Early orthodontic intervention shows superior efficacy in managing Class II malocclusion compared to late intervention. Early treatment leads to greater reductions in overjet, improvements in molar relationship, and favorable changes in skeletal and dental parameters. These findings underscore the importance of timely orthodontic intervention, particularly during the mixed dentition stage, for optimal management of Class II malocclusion.

Planned and achieved overjet and overbite changes following an initial series of Invisalign® aligners: A retrospective study of adolescent patients

The aim of the present study was to compare the changes in overjet and overbite measurements achieved in adolescent patients following an initial series of Invisalign® aligners (Align Technology, San Jose, California) with those planned by orthodontists via its ClinCheck® digital treatment planning facility. Data provided by Align regarding patients who had completed an initial series of Invisalign® aligner treatment and were less than 18-years old were assessed in relation to pre-treatment, planned and achieved overjet and overbite measurements. Descriptive statistics, Wilcoxon rank-sum, Mann Whitney calculations were computed. A total of 290 patients satisfied inclusion criteria. The median (interquartile range (IQR)) age was 14.17 (13,15.42) years. The median achieved overjet and overbite changes were less than those planned (p<0.01) with 53.33% of the planned median overjet increase achieved and 52.94% of planned median overjet reduction achieved. Additionally, 58.33% of the planned median overbite increase was achieved and 55.55% of the planned median overbite reduction was achieved. A total of 21.52% patients recorded no change or an increase from pre-treatment to the achieved overjet where reduction was planned, whereas 41.67% recorded no change or a reduction in overjet where increase was planned. A total of 18.72% recorded no change or an increase in overbite where reduction was planned, whereas 20.75% recorded no change or a reduction in overbite where increase was planned. Less than 60% of the planned overjet and overbite changes per patient were achieved. Between 18.72 and 41.67% of patients experienced no change or changes in overjet and overbite in the opposite direction to that planned. This is likely to be clinically significant.

Clinical efficacy of the Invisalign mandibular advancement appliance: A retrospective investigation

This retrospective investigation aimed to determine whether the achieved changes in the treatment of Class II malocclusion were the same as those planned after the prescribed wear of an initial phase of Invisalign treatment with the mandibular advancement appliance (MAA) (Align Technology, Santa Jose, Calif). All patients treated with the MAA and who satisfied inclusion/exclusion criteria were selected from a database of 16,500 patients treated with clear aligners by 16 orthodontists. The pretreatment, planned, and achieved overjet measurements were documented from data provided in Align Technology's software facility, ClinCheck. Changes in intermaxillary anteroposterior (AP) first permanent molar (FPM) relationships were evaluated using Geomagic Control X (3D systems, Rock Hill, SC) metrology software. Most of the 195 patients who satisfied the inclusion criteria were females (n= 104; 53.3%). The mean age was 12.62 ± 2.20 years. The pretreatment overjet was reduced from 6.49 ± 2.86 mm to 4.61 ± 2.22 mm after prescribed MAA wear, which was 42.5% of the planned outcome. The pretreatment AP FPM reduced from 3.14 ± 1.95 mm to 2.24 ± 2.51 mm, which was 31.3% of that planned. Thirty-eight (19.5%) patients experienced an increase in overjet where a reduction was planned. Less than half of the planned overjet reduction and less than a third of the planned AP FPM correction were achieved with the MAA. Almost 20% of patients completed the MAA phase of treatment with an increased overjet despite a reduction being planned.

The Effect of Early Orthodontic Treatment on Long-Term Stability of Class II Malocclusions

ABSTRACT Background: Class II malocclusions are a common dental issue characterized by the misalignment of the upper and lower teeth. Early orthodontic treatment is often considered to correct these malocclusions, but its long-term effectiveness remains unclear. Materials and Methods: In this study, we examined the impact of early orthodontic treatment on the long-term stability of Class II malocclusions. We conducted a retrospective analysis of dental records from a sample of 150 patients who had received early orthodontic treatment for Class II malocclusions. The treatment involved braces and other orthodontic appliances. We compared their dental measurements before and after treatment, with a follow-up period of 5 years. Results: Our analysis revealed that the early orthodontic treatment led to a significant improvement in the alignment of upper and lower teeth, as indicated by a reduction in the overjet (the horizontal distance between upper and lower incisors). The mean overjet reduction was 3.2 millimeters. Furthermore, the Angle’s Class II molar relationship was corrected in 80% of the cases. Conclusion: Early orthodontic treatment for Class II malocclusions demonstrated positive long-term stability, as evidenced by a reduction in overjet and improvement in molar relationships.

Assessment of Patient Satisfaction and Functional Outcomes in Orthognathic Surgery.

Orthognathic surgery is a surgical procedure performed to correct severe jaw misalignments that can affect a patient's facial aesthetics and functional occlusion. While the primary goal of orthognathic surgery is to improve functional outcomes and facial appearance, it is essential to assess patient satisfaction as a crucial aspect of overall treatment success. Patient selection: We conducted a prospective study involving 50 patients who underwent orthognathic surgery. All patients had a confirmed diagnosis of severe jaw misalignment, as determined by clinical and radiographic assessments. The surgical procedures performed included maxillary advancement, mandibular setback, or a combination of both, depending on the patient's specific diagnosis. Preoperative orthodontic treatment was provided to align the teeth and prepare the patient for surgery. Patients were evaluated preoperatively and at postoperative intervals of 3 months, 6 months, and 1 year. Patient satisfaction scores and functional outcomes were as follows: aesthetics of facial profile (1-year post-op): mean score = 4.6, chewing function (1-year post-op): mean score = 4.4, speech function (1-year post-op): mean score = 4.3, and overall satisfaction with surgical outcome (1-year post-op): mean score = 4.5. Objective assessments revealed a significant improvement in occlusion and facial aesthetics. The mean reduction in overjet was 4.8 mm, and the mean reduction in overbite was 3.2 mm. Additionally, the mean postoperative ANB angle improved by 3.7°, indicating a better facial balance. Orthognathic surgery in our cohort of 50 patients resulted in high levels of patient satisfaction with both functional outcomes and facial aesthetics. Objective measurements also indicated significant improvements in occlusion and facial balance.

The Impact of Early Orthodontic Intervention on Dental and Skeletal Development in Children with Mixed Dentition.

The mixed dentition stage in children is a critical period for orthodontic assessment and intervention. This study investigates the effects of interceptive orthodontics on dental and skeletal development in children with mixed dentition, aiming to evaluate the potential benefits of early orthodontic treatment. A retrospective analysis was conducted on a cohort of 150 children with mixed dentition (aged 7-11 years), who received interceptive orthodontic treatment. Dental and skeletal records, including cephalometric radiographs and dental cast models, were collected before and after treatment. A control group of 150 untreated children with mixed dentition was also assessed for comparison. Various dental and skeletal parameters, such as dental alignment, overjet (OJ), overbite (OB), and cephalometric measurements, were recorded and analyzed. The results of this study indicate significant improvements in dental alignment and occlusion in the group of children who received interceptive orthodontic treatment. The average reduction in OJ was 3.5 mm, and the OB correction averaged 2.1 mm. Cephalometric analysis showed positive changes in skeletal relationships, with a mean reduction in the angle formed by point A, nasion (N) and point B. (ANB) angle of 2.8 degrees. These improvements were statistically significant compared to the control group (P < 0.05). Early orthodontic intervention, such as interceptive orthodontics, has a positive impact on dental and skeletal development in children with mixed dentition.

Objectively measured adherence may affect side effects of mandibular advancement therapy in subjects with obstructive sleep apnea

PurposeThe purpose of this study was to determine if objectively measured adherence to oral appliance (OA) treatment may affect dental changes and temporomandibular disorders (TMD) in patients with obstructive sleep apnea (OSA).MethodsThe original study group consisted of adults with OSA who were referred for OA therapy. Eight indicators of subjective side effects of using OA (temporomandibular joint (TMJ) and muscle pain, pain in teeth, jaw stiffness in the morning, clicking, dry mouth, hypersalivation, gingival irritation) were evaluated by a questionnaire. Three occlusal indicators (overjet, overbite, molar occlusion) and clinical TMD signs (TMJ pain, muscle pain, clicking, jaw deviation on opening) were evaluated at baseline and at the 3-, 6-, and 12-month follow-up. In addition, objective adherence monitoring for OA was registered. Statistical analyses included the chi-square test, Fisher’s exact test, paired sample t-test, and linear regression analyses.ResultsA total of 58 adults with OSA were referred for OA therapy. Mean (SD) age was 50.7 (11.7) and mean apnea-hypopnea index (AHI) was 19.5 (10.0). At 1-year follow-up, the study group consisted of 28 men and 12 women. Overjet but not overbite reduced significantly after 1-year OA therapy. The average nightly wear of OA was related to overjet and overbite reduction, and to TMD signs. Hypersalivation, dry mouth, and tooth discomfort were the most common subjective side effects of OA therapy.ConclusionThere was a time-dependent relationship with the nightly wear of OA and reduction in overjet and overbite, and clinical TMD signs. With 60% of mandibular advancement, dental changes and TM-disorders were considered mild/minor in the 1‐year study period.

A Comparative Analysis of Treatment Effects of PowerScope and AdvanSync2 in Class II Division 1 Malocclusion: A Retrospective Study.

Fixed functional appliances are widely used for the treatment of retrognathic mandibles in skeletal class II malocclusion. The primary objective of the present investigation was to evaluate and compare the treatment effects induced by PowerScope (American Orthodontics, Sheboygan, WI) and AdvanSync2 (Ormco, Orange, CA). The hypothesis posited that there were no notable disparities in the therapeutic impacts of the two appliances. A retrospective study was undertaken involving 90 subjects with retrognathic mandibles. Group 1 was treated with AdvanSync2, group 2 received PowerScope treatment, and group 3 consisted of an untreated class II control sample. Lateral cephalograms were traced at pre-treatment (T0) and post-treatment (T1), to measure various skeletal, dental, and soft tissue parameters. The comparison between the groups was done using analysis of variance (ANOVA) and post-hoc analysis by Tukey's test. Significant changes were observed in all the parameters, comparing the effects of both appliances to the control group (p < 0.05). AdvanSync2 displayed statistically significant skeletal effects on the maxillaand mandible (p <0.05). The statistically significant differences were also seen for dental effects such as reduction in overbite and overjet. On the other hand, PowerScope exhibited effects that were not considered statistically significant on the maxilla, instead primarily manifesting dento-alveolar changes that led to a considerable reduction in overbite. In comparison to the control group, both appliances notably produced soft tissue changes. Our study rejected the null hypothesis. AdvanSync2 yielded superior skeletal outcomes with greater mandibular advancement, compared to PowerScope, which exhibited enhanced dento-alveolar alterations. AdvanSync2 took less treatment time, compared toPowerScope.

A comparison of skeletal and dental changes in patients with a Class II relationship treated with clear aligner mandibular advancement and Herbst appliance followed by comprehensive orthodontic treatment

The objective of this study was to compare the skeletal and dental changes of patients with a Class II relationship treated with clear aligner mandibular advancement (MA) and Herbst appliances followed by comprehensive orthodontic treatment. The participants included 20 patients treated with MA and 20 with the Herbst appliance. Orthodontic records were taken before treatment, after the functional appliance, and completion of phase II treatment. The skeletal and dental changes across the 3-time periods were evaluated using a matched paired t test for each treatment. A 2-sample t test was used to examine the changes across periods between 2 treatment groups (P<0.05). Significant reduction in overjet, overbite, and change in molar relationship were obtained by both appliances with similar skeletal and dental contributions. This was contributed by a forward movement of the mandible and mandibular molars, backward movement of the maxillary molars, and retraction of the maxillary incisors. After phase II treatment, both appliances could maintain the skeletal and dental changes achieved during the advancement phase. Greater change in overbite (2.4 mm vs 1.4 mm), an eruption of maxillary incisors (0.9 mm vs 0.1 mm), and proclination of mandibular incisors were found with the Herbst group (3.9° vs -2.1°). The average total treatment time was similar with the 2 appliances. Both functional appliances were equally effective in reducing the overjet and overbite and achieving a Class I molar relationship with a similar length of treatment time. The Herbst design lacked control of the mandibular incisor proclination, and clear aligners offered better vertical control and management of the mandibular incisor inclination.

Three-dimensional Evaluation of the Carriere Motion 3D Appliance in the treatment of Class II malocclusion

This study aimed to quantify the outcomes of adolescent patients with Class II malocclusion treated with the Carriere Motion 3D Appliance (CMA) combined with full fixed appliances. Cone-beam computed tomography scans of 22 patients were available before orthodontic treatment (T1), at removal of the CMA (T2), and posttreatment (T3). The average age of the patients was 13.5 ± 1.6 years at T1, 14.1 ± 0.2 years at T2, and 15.6 ± 0.5 years at T3. The 3-dimensional image analysis procedures were performed using ITK-SNAP (version 3.6.0; www.itksnap.org, Hatfield, Pa) and SlicerCMF (version 4.11.0; http://www.slicer.org, Cambridge, Mass); skeletal and dentoalveolar changes relative to cranial base, maxillary, and mandibular regional superimpositions were evaluated. Changes were analyzed with 1 sample t tests using the mean differences during the CMA phase (T1 to T2) and total treatment time (T1 to T3). Significant skeletal changes included a slight reduction of ANB from T1 to T3, mandibular growth (Co-Gn increment of 1.2 mm and 3.3 mm from T1 to T2 and T1 to T3, respectively), inferior displacement of point A, and anterior and inferior displacement of point B. The mandibular plane did not change significantly during treatment. During the CMA treatment, posterior tipping and distal rotation of the maxillary molars, tip back and inferior displacement of the maxillary canines, significant mesial rotation, and superior displacement of the mandibular molars were observed. These movements rebounded during the full fixed appliance phase except for the molar and canine vertical displacements. Clinically significant dental changes during treatment included a reduction in overjet and overbite, Class II correction of the molar and canine relationship, and proclination of the mandibular incisors. The CMA is an effective treatment modality for Class II correction in growing patients because of a combination of mesial movement of the mandibular molar, distal rotation of the maxillary molar, and anterior displacement of the mandible.

The use of the Hanks Herbst vs Twin-block in Class II malocclusion: A randomized controlled trial

This 2-arm parallel study aimed to compare and evaluate the efficiency of Hanks Herbst (HH) and Twin-block (TB) functional appliances in treating adolescents with Class II malocclusion. A parallel-group randomized controlled trial was undertaken in a single United Kingdom hospital. Eighty participants were recruited and randomized in a 1:1 ratio to receive either the HH or TB appliance. Eligibility criteria included children aged 10-14 years with an overjet of ≥7 mm without dental anomalies. The primary outcome was the time (in months) required to reduce overjet to normal limits (<4 mm). Secondary outcomes included treatment failure rates, complications and their impact on oral health-related quality of life (OHRQOL). Randomization was accomplished using electronic software with allocation concealed using sequentially numbered, opaque, and sealed envelopes. Blinding was only applicable for outcome assessment. Data were analyzed using descriptive statistics and regression analyses to detect between-group differences, including Cox regression for time to treatment success. HH was significantly faster than TB in reducing the overjet to within normal limits (95% confidence interval [CI], -3.00 to -0.03; P= 0.046). Mean overjet reduction was more efficient with the HH than the TB appliance (ß= 1.3; 95% CI, 0.04-2.40; P= 0.04). Fifteen (37.5%) of the participants in the TB group and 7 (17.5%) in the HH group failed to complete the treatment (hazard ratio= 0.54; 95% CI, 0.32-0.91, P= 0.02). However, TB was associated with fewer routine (incidence rate ratio= 0.81; 95% CI, 0.7-0.9; P= 0.004) and emergency (incidence rate ratio= 0.1; 95% CI, 0.1-0.3; P= 0.001) visits. Chairside time was greater with the HH (ß= 2.7; 95% CI, 1.8-3.6, P= 0.001). Participants in both groups experienced complications with similar frequency. A greater deterioration in OHRQOL was found during treatment with the TB. Treatment with HH resulted in more efficient and predictable overjet reduction than TB. More treatment discontinuation and greater deterioration in OHRQOL were observed with the TB. However, HH was associated with more routine and emergency visits. ISRCTN11717011. The protocol was not published before trial commencement. No specific external or internal funding was provided. Treatment for participants was provided as part of routine orthodontic treatment in the hospital.

Does the timing of treatment affect the clinical and psychological outcomes of Twin-block therapy?

This study is a multicenter, two-arm parallel randomized control trial carried out across 3 hospital orthodontic units. A total of 75 patients participated in the study, with 41 randomly allocated in an Immediate Treatment Group (ITG) and 34 randomly allocated into an 18-month delayed Later Treatment Group (LTG). The patients were aware as to which group they were being allocated, as were the clinicians. Both patient groups received the same twin block appliance for use during the study. The appliance was to be worn full time, including eating, but to be removed while participating in contact sports or swimming. Achieving an overjet reduction between 2-4 mm was defined as being the clinical endpoint. After this, the appliance was only worn at night up until the next data collection point, allowing an 18-month window to finish treatment. Blinded clinicians measured skeletal changes using lateral cephalograms and overjet change via study models. Psychological impact was measured using two questionnaires: Oral Aesthetic Subjective Impact Scale (OASIS) and the Oral Health Quality of Life (OHQL). Data was collected from when the patient first registered in the study (DC1), 18 months after registration (DC2) and 3 years after registration (DC3). In total, 41 boys and 34 girls were included in the study. Ages for the boys ranged from within 1 month of their 12th birthday to 13.5 years old. For the girls, the range was from within 1 month of their 11th birthday to 12.5 years old. Further inclusion criteria included a class II skeletal pattern and having an overjet of 7 mm+. Exclusion criteria included patients of non-white Caucasian origin, girls aged 12.5 years+ and boys aged 13.5 years+. Furthermore, patients with a history of cleft lip or palate, mandibular asymmetry, muscular dystrophy, general health precluding compliance with treatment, a medically diagnosed growth excess or deficiency, not dentally fit or having previously received orthodontic treatment were not included in the study. SPSS Version 25 software was used to undertake the data analysis. No formal statistical testing was undertaken. To analyze and compare the scores between the two groups, independent t-tests were used. All analysis was carried out at 0.05 level of significance. The reliability of the examining clinicians was assessed using Bland-Altman limits of agreement. As only the ITG were in treatment over the periods of DC1-DC2 a comparison of the clinical outcomes cannot be made. With regards to the psychological outcome, no statically significant impact was noted for the ITG when compared with the LTG, who had not started treatment (OASIS P = 0.53, OHQL P = 0.92). When comparing the treatment effects of twin block therapy for the ITG (DC1-DC2) and the LTG (DC2-DC3), study model overjet and cephalometric changes were not statistically significant with the exception of % lower facial height (which was deemed not to be clinically significant) and mandibular unit length. There was no statistical significance with regards to the psychological outcomes post treatment when comparing the groups (OASIS P = 0.30, OHQL P = 0.85) CONCLUSIONS: The findings of this study suggest that adolescents (with a mean age of 12 years 8 months for boys and 11 years 8 months for girls) will not be disadvantaged, either clinically or psychologically, by waiting 18 months for twin block therapy.

Is PowerScope2 an effective Class II corrector ? A prospective cephalometric study

The study was carried out to evaluate skeletal, dental and soft tissue effects produced by PowerScope 2 appliance following the correction of skeletal Class II malocclusion.A total of 10 patients (3 males and 7 females with mean age of 14.40 ± 0.70 yrs) diagnosed with skeletal Class II malocclusion and indicated for fixed functional appliance were treated using Power Scope2 appliance. Paired t-test was used to assess skeletal, dental and soft tissue changes evaluated on lateral cephalograms taken at pre-functional (T1) and post-functional (T2) stages. Maxillomandibular sagittal relation was markedly improved with a significant gain in the length of the mandible along with a restraining effect on the maxillary dentition. The improvement in molar relation was mainly contributed by dentoalveolar effects (72.3 %) and secondarily by skeletal effects (27.7 %) while the reduction in overjet was contributed by 22.4% skeletal and 77.6% dental effects. Vertical changes were non-significant. Following PowerScope 2 therapy there was an overall improvement in facial esthetics.Power Scope2 serves as an effective skeletal Class II corrector with primarily dentoalveolar and secondary skeletal effects.

Comparison between clear aligners and twin-block in treating class II malocclusion in children: a retrospective study.

The study herein evaluated and compared the efficacy of Clear Aligners (CA) and Twin-Block (TB) appliances as the early orthodontic treatments of developing class II division 1 malocclusion. Twenty-four patients each for CA (11.73 ± 0.33 y) and TB (11.87 ± 0.34 y) groups were selected according to the inclusion and exclusion criteria. The cephalometric X-rays and intraoral photos were taken for the patients after nearly 12 months of treatment. Treatment impacts were evaluated by the molar correction and overjet reduction. The vertical and sagittal changes were analyzed through cephalometric measurements. Sella-nasion-point B angle (SNB), point A-nasion-point B angle (ANB), Wits Appraisal (AO-BO) and overjet were statistically significant regarding the sagittal changes analyzed before and after the treatments in both groups, respectively. So, no significant difference was noted in the sagittal changes between CA and TB groups. However, for the vertical changes, OP (occlusal plane) angle of CA group and OP angle, AFH (anterior facial height) and PFH (posterior facial height) of TB group were statistically significant. Moreover, the Z angle and cranial facial difficulty (C.F. difficulty) were also statistically significant in both groups. Class II children with retrognathic mandible are effectively treated by employing the CA, which has almost the same impact as of TB in sagittal and vertical changes. Resultantly, the patient profile is improved. The CA and TB treatments thus minimize the subsequent treatment difficulty by reducing the C.F. difficulty.

Dental and Skeletal Effects of Herbst Appliance, Forsus Fatigue Resistance Device, and Class II Elastics-A Systematic Review and Meta-Analysis.

Background: Our study aimed to systematically summarize the dentoskeletal effects of Herbst appliance; Forsus fatigue resistance device; and Class II elastics in adolescent Class II malocclusion. Methods: Five databases; unpublished literature; and reference lists were last searched in August 2022. Randomized clinical trials and observational studies of at least 10 Class II growing patients that assessed dentoskeletal effects through cephalometric/CBCT superimpositions were eligible. The included studies quality was assessed with the RoB 2 and ROBINS-I tools. A random-effects model meta-analysis was performed. Heterogeneity was explored with subgroup and sensitivity analyses. Results: Among nine studies (298 patients); two-to-three studies were included in each meta-analysis. Less post-treatment upper incisor retroclination (<2) and no overbite; overjet; SNA; SNB; and lower incisor inclination differences were found between Herbst/Forsus and Class II elastics. No differences in maxilla; condyle; glenoid fossa; and most mandibular changes were found between Herbst and Class II elastics; except for a greater 1.5 mm increase in mandibular length and right mandibular ramus height (1.6 mm) with Herbst. Conclusions: Herbst and Class II elastics corrected the molar relationship; but Herbst moved the lower molars more mesially. Apart from an additional mandibular length increase; no other dental and anteroposterior skeletal difference was found. Forsus was more effective in molar correction; overjet reduction; and upper incisor control than Class II elastics. Trial registration number OSF: 10.17605/OSF.IO/8TK3R.

Evaluation of hard and soft tissue changes after en- masse retraction using orthodontic mini-implants: An in-vivo study

Introduction: The procedures used for closing the extraction space results in the correction of proclination of incisors, reduction in overjet and elimination of extraction sites. This space closure has been achieved using different mechanics but most recently orthodontic mini-implants (TAD’s) have been used efficiently.Aim: To evaluate the skeletal, dental, soft tissue changes and amount of anchor loss in the treatment outcomes using orthodontic mini-implants.Materials and Methods: 25 subjects with Class I bimaxillary protrusion were selected from the patients visiting the department of orthodontics for seeking orthodontic treatment. In all the patients, after extraction of the 1st premolars, retraction was carried out by using mini implants in the maxillary arch. Results: Significant retraction was achieved in all the cases with minimum anchorage loss and significant improvement in patient’s profile.Conclusion: Orthodontic mini-implants have revolutionized the orthodontic world and have been an effective way of achieving desired tooth movement in an effective way.

Should we recommend early overjet reduction to prevent dental trauma?

There is an association between increased overjet and risk of trauma to the maxillary incisor teeth in children and adolescents. It would therefore seem sensible to recommend overjet reduction as early as possible to help reduce this risk. However, orthodontic outcomes are essentially the same whether you start treatment in the early or late mixed dentition, while early treatment carries a heavier burden on compliance - taking longer and involving more appointments. This article explores the complex association between early overjet reduction and dental trauma in the context of current best evidence. Careful case selection is advised when justifying early intervention for increased overjet based on reducing trauma risk.

Skeletal, Dental and Soft Tissue Cephalometric Changes after Orthodontic Treatment of Dental Class II Malocclusion with Maxillary First Molar or First Premolar Extractions.

The aim of the present retrospective study was evaluating skeletal, dental and soft tissue changes of two groups of Class II patients orthodontically treated with extractions of upper first premolars (U4 group) and upper first molars (U6 group). In total, 21 patient records (9M and 12F; mean age 12.5 ± 1.2 years) were selected for the U4 group, and 38 patient records (17M and 21F; mean age 13.2 ± 1.3 years) were recruited for the U6 group. Twenty cephalometric variables were analysed on standardised lateral cephalograms at baseline (T0) and at the end of orthodontic treatment (T1). Means and standard deviations (SDs) were calculated for both groups and increments were calculated. After revealing the normal distribution of data with the Shapiro–Wilk test, Student’s t-test was used to compare variables at T0 between groups. A paired t-test was used to analyse changes between time points within each group, and Student’s t-test to compare differences between groups at T1. Both groups showed a significant increase in the distance among upper second molars and the vertical pterygoid line (PTV-maxillary second molar centroid U6 group: 6.66 ± 5.00 mm; U4 group: 3.66 ± 2.20 mm). Moreover, the distance of upper incisors to the palatal plane significantly increased (PP-maxillary incisor tip U6 group: 1.09 ± 1.52 mm; U4 group: 0.20 ± 2.00 mm; p = 0.061). Significant changes were found for overjet (U6 group: −4.86 ± 1.62 mm; U4 group: −3.27 ± 1.90 mm; p = 0.001). The distance between upper lip and esthetic plane showed a significantly reduction in both groups (ULip-E Plane U6 group: −2.98 ± 1.65 mm; U4 group: −1.93 ± 1.57 mm). No statistically significant changes were found in sagittal or vertical skeletal values. The significantly larger reduction of upper lip protrusion and overjet in the U6 group compared to the U4 group suggests preferring molar extraction treatment for severe Class II with protrusive soft tissues’ profile and increased overjet. Since no differences on vertical values were found, an increased SN^GoGn angle should not be considered a discriminating factor for choosing molar extraction treatment.