Mauro Cozzani

Objectives: Conventional overjet is widely used to describe sagittal interarch relationships, but its measurement depends on predefined landmarks and acquisition methods. This study aimed to describe a standardized three-dimensional method, termed 3D Clinical Overjet, for measuring the minimum sagittal distance between anterior dental surfaces in Class II malocclusion. Methods: This retrospective methodological study applied the proposed protocol to 42 consecutive growing patients with skeletal and dental Class II malocclusion. Digital intraoral scans obtained at baseline (T0) and immediately before mandibular advancement (T1) were analyzed by a single examiner. 3D Clinical Overjet was defined as the minimum linear distance, measured parallel to the occlusal plane, between the labial surface of any mandibular incisor and the palatal surface of the nearest maxillary incisor. No intra- or inter-examiner reliability assessment was performed because the study was designed to demonstrate feasibility rather than validate measurement properties. Associations with radiographic overjet were assessed using Spearman’s rank correlation; T0–T1 changes were analyzed using the Wilcoxon signed-rank test, and tooth-distribution changes were analyzed using a marginal homogeneity test. Results: 3D Clinical Overjet was obtained in all 42 subjects at T0 and in 41 at T1. Among the 41 subjects with paired observations, median 3D Clinical Overjet increased from 0.60 [0.10–2.00] mm at T0 to 1.70 [0.60–4.30] mm at T1 (W = 224, p = 0.054; rank-biserial correlation = 0.36). The maxillary tooth determining the minimum distance varied among patients and across time points. 3D Clinical Overjet was not significantly associated with radiographic overjet at T0 (Spearman ρ = 0.095, p = 0.558; n = 40). Conclusions: 3D Clinical Overjet is a feasible surface-based three-dimensional method for identifying the minimum sagittal distance across the anterior dentition without restricting measurement to a predefined incisor pair. In this sample, the tooth determining the minimum distance varied among patients and across time points, and 3D Clinical Overjet showed no significant association with radiographic overjet. These findings support the feasibility of the proposed geometric approach; its reproducibility, validity, and clinical relevance remain to be established.

Background: The majority of Class II malocclusions stem from mandibular deficiency, leading to chin retrusion. In growing patients, the ideal correction—aiming for a skeletal mandibular response—should avoid common pitfalls such as “Point B” dropping postero-inferiorly, excessive labial proclination of mandibular incisors, or the lingual tipping and extrusion of maxillary incisors. When planning mandibular advancement (MA) using clear aligners with integrated advancement features, biomechanical forces are not the only consideration; precise management of the lower incisor position is critical for success. Current literature highlights not a good control in digital planning software: these platforms are primarily dentoalveolar-based and lack integrated cephalometric analysis. Consequently, mandibular advancement is often defined by standard linear parameters (typically 2 mm per step), while incisor position is managed through virtual alignment without correlation to cephalometric landmarks like the Pogonion, NB line, or IMPA. The software cannot monitor real-time sagittal or vertical skeletal relationships, the software will elaborate the treatment planning after doctor’s prescription, the clinician must manually adjust incisor positioning based on external cephalometric analysis to prevent dental compensation or excessive proclination. Aim: This clinical case demonstrates a specific arch preparation protocol designed to optimize mandibular advancement in a growing patient with mandibular retrusion. Methods: A 12-year-old female presented with a skeletal and dental Class II malocclusion, characterized by increased overjet and a normal overbite. Treatment was conducted using Invisalign^® clear aligners (22 h/day wear, weekly changes). The treatment objectives were: transverse: Correct upper dentoalveolar contraction and coordinate arch form while restoring midline alignment; sagittal: establish Class I molar and canine relationships by correcting the overjet and reducing the labial inclination of the lower incisors; vertical: level the curve of Spee. A key clinical condition of our protocol was the pre-advancement phase: the lower arch was reshaped by reducing the buccolingual inclination (retroclination) and intruding the lower incisors. This was specifically intended to increase the available overjet space, creating the necessary room for subsequent mandibular advancement. Results Treatment was completed in 24 months with high patient compliance. Objectives were successfully met, including the correction of skeletal and dental discrepancies, the establishment of harmonious arch forms, and precise overjet reduction through enhanced control of the mandibular incisors. Conclusions: This case report outlines an optimized clinical strategy for Class II correction. Cephalometric Integration: Perform an initial analysis outside the digital planning software to define the ideal IMPA and NB angles. Anatomic Verification: Utilize radiographic overlays to ensure tooth movement remains within alveolar bone limits. Pre-MA Optimization: Prioritize a “pre-advancement” phase to maximize the sagittal inter-arch space (overjet). A larger overjet allows for a more significant orthopedic effect from the MA features. Stepwise Advancement: Implement mandibular advancement in increments (≥2 mm) with periodic clinical reassessment to facilitate the adaptation of the muscular sling and functional occlusion.

Introduction: This study aimed to evaluate the educational value of YouTube videos presenting information on pediatric orthodontic treatments, specifically clear aligners, fixed braces, and lingual braces. Methods: A cross-sectional analysis was conducted on 150 of the most-viewed English-language YouTube videos (50 per treatment type). Videos were assessed for accuracy, depth of explanation, source type (expert, commercial, or general user), and viewer engagement metrics. Statistical comparisons were made using the Kruskal–Wallis test and Dunn’s post hoc tests with Bonferroni correction. Results: Fixed brace videos demonstrated more accuracy (average score 4.2/5), than both clear aligners (p = 0.03) and lingual braces (p < 0.001), with 60% originating from expert sources. Clear aligner and lingual brace videos had lower accuracy scores (3.8 and 3.5, respectively), reflecting higher proportions of commercial influence (50% and 55%). The findings highlighted the predominance of promotional content in clear aligner and lingual brace videos, raising concerns about potential misinformation. Conclusions: YouTube provides accessible but variable-quality information on pediatric orthodontics. Fixed brace videos offer more reliable educational content, while clear aligner and lingual brace videos are more susceptible to commercial bias. Efforts to promote expert-driven content and implement content verification systems are needed to improve the quality of online orthodontic information for parents and caregivers.

Background: Class II Division 1 malocclusion is often characterized by an increased overjet, which has traditionally been considered a negative predictor of aesthetic outcomes, treatment efficacy, and long-term stability. Although early two-phase treatment is generally perceived as less effective than a single-stage pubertal peak intervention, it may be beneficial in cases with concerns such as trauma risk or bullying. This study aimed to assess the relationship between initial overjet and sagittal correction (as measured by the ANB and WITS indices) to identify a threshold beyond which two-phase treatment might be more effective. Methods: A retrospective analysis was conducted on 58 patients (mean age: 9.01 years), all of whom were treated consecutively with the Manni Telescopic Herbst Appliance. Lateral cephalograms taken at the start (T0) and end (T1) of Herbst treatment were analyzed to evaluate changes in skeletal and dental parameters. Results: A significant positive correlation was found between higher initial overjet and increased skeletal sagittal correction. Specifically, for every 1 mm increase in overjet, there was a 0.65 mm reduction in the WITS index and a 0.30° decrease in the ANB angle (p < 0.01). These effects were more pronounced when the initial overjet exceeded 8.0 mm. Conclusions: The Manni Telescopic Herbst Appliance demonstrated enhanced skeletal correction in patients with larger initial overjet values, particularly when the overjet exceeded 8.0 mm. This suggests that early two-phase treatment may be especially beneficial in such cases.

Aim: Class II Division I malocclusion poses significant challenges in orthodontics. The combination of a Herbst appliance and miniscrew anchorage emerged as a practical solution to improve skeletal and dental outcomes. This study employed finite element analysis to evaluate the biomechanical effects of a miniscrew-supported Herbst appliance on mandibular advancement and dentition movement. Methods: High-definition CBCT scans captured the maxilla and mandible’s detailed dental anatomy. The scans were stored in DICOM format for seamless integration with Mimics software (Mimics Innovation Suite research version 21.0, Materialise NV, Leuven, Belgium) for 3D reconstruction and model refinement. The appliance, designed with a maxillary fixed palatal arch and mandibular acrylic splint connected by telescoping rods, incorporated titanium TADs and elastic chains. STL models were optimized in Geomagic x Design for finite element analysis in Abaqus, assigning validated mechanical properties for materials. Tetrahedral meshing and realistic boundary conditions simulated biomechanical interactions. Tetrahedral C3D4 elements were used for meshing, ensuring a balance between computational efficiency and detailed anatomical representation. Tetrahedral meshing and realistic boundary conditions simulated biomechanical interactions. Dynamic simulations in CATIA evaluated mandibular movement. FEA analyzed displacement across dentoalveolar structures along the X, Y, and Z axes to assess treatment efficacy and biomechanical stability. Results: The Z displacement analysis revealed that the incisal edges of the lower central, lateral, and canines shifted lingually by 0.41, 0.4, and 0.47 mm, respectively. Additionally, the apices of the lower central, lateral, and canines displaced backwards by 0.05 mm, 0.05 mm, and 0.07 mm, respectively. Conclusions: The appliance facilitated mandibular advancement, bodily retracted the lower incisors, well-controlled the upper ones, and mesial-tipped the upper posterior teeth. In contrast with traditional functional appliances, it caused the lower anterior teeth to move backwards, while skeletal anchorage overcame some shortcomings of nonsurgical treatments. This method might be a good treatment option for growing skeletal Class II patients.

Objectives: The treatment of class II patients with mandibular retrusion often involves the use of a Herbst appliance, due to its efficiency and reduced need for compliance. Despite skeletal benefits, undesired dental effects, caused by anchorage loss, could reduce mandibular advancement, especially after the pubertal peak. Although the period between cervical vertebral maturation (CVM) 3 and CMV4 is considered the best choice to maximize the orthopedic outcome, clinicians cannot always treat patients during this ideal time window, as they present at their first visit later. The goal of this study is to evaluate whether the combination of an acrylic splint Herbst appliance with skeletal anchorage and elastic chains in both the upper and lower arch (Skeletal Therapy Manni Telescopic Herbst 4: STM4) could improve the efficiency of functional treatment also in CVM 5–6 patients. Methods: Lateral cephalograms of 10 consecutively treated patients taken at the beginning and at the end of the Herbst phase were analyzed and compared with those of 10 untreated patients of the same sex, age, malocclusion, and skeletal maturation. Results: According to the Pancherz analysis, the treated group of patients showed the significant advancement of the pogonion (4.75 mm), with a reduction in ANB (−3.3°) and Wits (−4.15 mm). The combination of miniscrews and elastic ligatures allowed the labial tipping of the upper incisors (+6.65°) and limited the labial flaring of the lower ones (+3.05°), maintaining the overjet needed for mandibular advancement. Conclusions: The STM4 technique might be an effective protocol for skeletal class II correction after the pubertal peak since it significantly reduces unfavorable dental compensations, increasing the skeletal effects and the esthetic outcome of the orthopedic treatment.

(1) Objectives: The purpose of this review was to compare the effects of combining skeletal anchorage and Class II devices, both from an overall perspective and individually for each type of appliance, considering as main outcomes the vertical dimensions and the inclination of the mandibular and maxillary incisors. (2) Materials and Methods: A search without time restrictions was performed up to February 2024 in PubMed, PubMed Central, Scopus, and Medline for randomized controlled trials, as well as prospective and retrospective cohort studies, considering Class II patients treated with and without skeletal anchorage. The effect measure used for the meta-analytic evaluation was the standardized mean difference (SMD). The SMD calculation was obtained by subtracting the mean values of T1–T0 for each individual treatment and then calculating the SMD between the treatments involved. The meta-analysis was performed using the standardized mean difference of the mean difference of the T1–T0 change in the outcome between the different treatments evaluated as the effect size. (3) Results: A total of 1217 documents were initially retrieved. According to the PRISMA protocol, 18 studies comparing different skeletal anchorage protocols (upper/lower miniscrews and miniplates), combined with four appliances (Herbst, Forsus, Carriere Motion, and elastics), were included in the analysis. No significant difference in skeletal divergence was found between groups from an overall point of view (SMD: 0.19 (−0.48 to 0.83) according to the random-effects model). A statistically significant reduction in IMPA° was found in patients treated with temporary anchorage devices (TADs) (SMD of 5.58 (3.40 to 7.75)), except for the elastics group (SMD: 3.76 (−0.91 to 8.43)). The effect on the upper incisors’ inclination appeared to be strictly dependent on the type of anchorage (TADs in one or both of the arches). Some limitations must be considered when interpreting the results: the small number of studies included and the heterogeneity among them are among the limitations, and the temporal disparity among some studies; the ages of the patients were not always comparable; and, finally, the clinical relevance of the effects of TADs is sometimes questionable. (4) Conclusions: The vertical dimension seems not to be significantly affected by skeletal anchorage; instead, the proclination of mandibular incisors is generally reduced when TADs are used. Skeletal anchorage might be useful if lingual tipping of the upper incisors is required; however, it is influenced by the anchorage protocol.