Background: Clear aligners (CA) are used 22 h daily, creating a bite-block effect. This work aims to (i) analyze occlusal changes before the beginning of treatment, after the first set of CA and after the use of additional aligners; (ii) compare planned occlusal contacts with the ones obtained after the first set of CA; (iii) analyze the occlusal changes occurred after reaching the orthodontic goals after 3 months of using CA only at night; (iv) evaluate and characterize which tooth movements did not allow the treatment to be completed at the end of the first set of aligners, and finally (v) verify the possible relation between the changes in occlusal contact and areas and parameters such as case complexity and facial biotype. Materials and Methods: A quantitative, comparative, and observational longitudinal cohort study design was implemented to evaluate the clinical data and the complexity levels of cases receiving CA. A non-probabilistic and convenience sample of 82 individuals was recruited. The orthodontic malocclusion traits were classified as simple, moderate, or complex corrections based on the basis of the Align^® recommendations with the Invisalign^® evaluation tool. According to the Invisalign^® criteria, patients need only one complex problem for their case to be classified as complex. Meshlab^® v. 2022.02, ClinCheck^® version Pro 6.0, My-Itero^® version 2.7.9.601 5d plus, and IBM^® SPSS Statistics software (Statistical Program for Social Sciences), version 27.0 for Windows were the software^® used. Results: A statistically significant decrease in area and occlusal contacts number were observed from before the start of orthodontic treatment (T0) to the end of treatment (T1). The changes in the occlusal area (from T0 to T1) were statistically different between hyperdivergent (28.24 [15.51–40.91]) and hypodivergent (16.23 [8.11–24.97]) biotypes (p = 0.031). A significant difference between the hyperdivergent (4.0 [2.0–5.0]) and normodivergent (5.5 [4.0–8.0]) group was found in T1 for the anterior contacts (p = 0.044). Anterior contacts obtained were significantly higher than the planned (p = 0.037) Between T1 and T2 statistically significant increases of occlusal areas, posterior and total contacts were observed. Conclusions: Occlusal contact and area were decreased, either at the end of the first set or after the use of additional aligners. Anterior occlusal contacts obtained were higher than planned as opposed to posterior occlusal contacts obtained. The hardest tooth movements to achieve to complete the treatment were distalization, rotation, and posterior extrusion. After completing orthodontic treatment (T1) to 3 months after (T2) using additional aligners only at night, posterior occlusal contacts were significantly increased, which could be due to the natural settling of the teeth in this period.

The increasing demand for more aesthetic/comfortable orthodontic alternatives fostered the utilization of clear aligners in recent years. However, the efficacy of clear aligners for treating complex malocclusions is often treated with scepticism. This case series aims to evaluate the predictability of the Invisalign^® First system in moderate and severe cases requiring interceptive orthodontic treatments in mixed dentition. A total of 23 patients with 102 interceptive orthodontic malocclusion traits were selected for orthodontic treatment with Invisalign^® First and were examined over 18 months (Phase 1). Clinical assessments included ClinCheck^® predictions, cephalometric measurements, and measuring tools commonly used to quantify tooth movement. Measurements taken at the beginning and end of the treatment were compared. The complexity degree of each case was established based on the set of problems presented by each patient. All treatment objectives were achieved within 18 months, except for two Class II cases, with 69% of them solved with the first set of aligners. Additional aligners were used in the remaining cases. Even though these 23 cases suggest that the Invisalign^® First (Phase 1) may be effective in most interceptive problems, controlled randomized clinical trials are required to evaluate movement predictability and how this relates to the problem complexity and additional aligners required.

Scissor bite (SB.) is a rare malocclusion that is challenging to diagnose and is often associated with a retrognathic mandible and a series of functional and structural abnormalities that negatively affect the patient. This article intends to analyze the treatment approaches applied to growing patients younger than 16 years old, comparing the conventional appliances described in the literature and a clinical case treated with clear aligners with mandibular advancement (MA.). SB is primarily related to skeletal Class I and II, according to Angle classification. In the various cases analyzed, it can also be mentioned as a significant number of cases with SB of dental origin (seven of dental and four of skeletal) in young patients. In children and adolescents who still have growth potential, the therapeutic possibilities are numerous. A comprehensive literature search was manually performed from 2002 until January 2023, in PubMed and BVS databases with the following conjugated keywords: “scissor bite OR brodie bite” AND “malocclusion” AND “treatment OR correction OR therapeutics”. The present case report on a young patient demonstrated the efficiency of the clear aligners with MA to correct an SB, associated with several functional and structural anomalies such as Class II division 1 with an increased overjet and overbite as well as a severe curve of Spee in a hypodivergent biotype.

Scissor bite does not correct spontaneously. It gradually worsens by overeruption, negatively affecting masticatory function. It is intended with this manuscript to evaluate the different treatment strategies to correct this malocclusion in adult patients, exploring treatment with clear aligners, bite ramps, and MS (miniscrews), especially in this case of a patient with unilateral right scissor bite, with high dental compensation in the three planes of space, asymmetrical sagittal dental position, overeruption on the scissor bite condition, and a high mandibular arch constriction and maxillary expansion. A comprehensive literature research was performed from 2002 until March 2023. PubMed and BVS databases were used, with the following keywords: “scissor bite OR brodie bite” AND “malocclusion” AND “treatment OR correction OR therapeutics”. Since correcting skeletal asymmetries after the growth completion is challenging, adult patient cases often involve a combined orthodontic‐surgical approach. In the present clinical case, the severe limitations to decompensating tooth positions for a surgical treatment, with the necessity to perform lower asymmetric extraction and a must longer orthodontic treatment, were the major reasons to avoid the surgical approach, after the scissor bite correction. In spite of this, the efficiency of the clear aligners and auxiliaries like bite ramps, MS, and elastics in successfully correcting a complex scissor bite in an adult patient was demonstrated, with significant esthetic and functional commitment, demonstrated by the case reliability PAR (peer assessment rating) index.

Background/Objectives: This study aimed to explore the functional implications of occlusal changes during clear aligner treatment (CAT) to (a) analyze occlusal changes throughout CAT and the extent of post-treatment occlusal recovery; (b) assess the relationship between post-treatment occlusion and masticatory performance; (c) investigate whether case complexity, facial biotype, and type of malocclusion influence occlusal adaptation and functional outcomes; and (d) evaluate the presence and progression of signs or symptoms of TMDs in patients undergoing CAT. Methods: This longitudinal cohort pilot study included 42 individuals who underwent CAT. Occlusion was evaluated at three timepoints: before treatment (T0), at treatment completion (T1), and three months after with night-only aligner use (T2). Masticatory performance was assessed using a two-colored chewing gum test analyzed through colorimetric software. TMD signs/symptoms were assessed using the Diagnostic Criteria for TMD [DC/TMD]. Statistical analysis used non-parametric tests. Results: A significant decrease in occlusal contact area was observed during active CAT [p = 0.016], which partially recovered at follow-up. Individuals with normal facial proportions (normodivergent) showed more anterior contacts at T1 compared to hyperdivergent individuals [p = 0.013]. Masticatory performance remained stable between T1 and T2 [p = 0.528]. A weak negative correlation was found between posterior contact number and performance score at T1 [r = −0.378, p < 0.05], suggesting that more contacts may be linked to better chewing. No TMD signs or symptoms were detected at any timepoint. Conclusions: Although CAT temporarily reduces occlusal contact area, it does not negatively impact chewing efficiency or trigger TMD symptoms. These findings support the functional safety of CAT when treatment is properly planned and monitored.