Clear Aligner Treatment Research Articles

Does Clear Aligner Treatment Result in Different Patient Perceptions of Treatment Process and Outcomes Compared to Conventional/Traditional Fixed Appliance Treatment: A Literature Review

This study sought to systematically review the literature to determine whether clear aligner treatment results in different patient perceptions of treatment process and outcomes compared with conventional fixed appliance treatment. A systematic review was conducted to identify studies that examined differences in patient perceptions between clear aligners and conventional fixed appliance treatment. Studies were identified through searching relevant terms using PubMed and Embase. Following review of identified articles, key information about the studies including study design, setting, comparison groups, sample size/response rate, study location, primary outcomes, and statistical tests used were extracted. A total of 13 articles were identified that met the inclusion criteria for this study. These studies described a variety of outcomes which were divided into two broad categories: treatment process (pain, chewing, speech, daily routine, etc.) and treatment outcomes (satisfaction level, smile outcome perceptions, etc.). There was the strongest evidence that clear aligners had a positive impact with respect to treatment process compared with fixed orthodontic appliances. This study highlights that clear aligners may be effective for improving treatment-process-related outcomes among orthodontic patients. More studies need to be conducted to determine whether clear aligners have a beneficial impact with respect to treatment outcomes.

A method of fabricating computer aided design-computer aided manufacturing implant-supported provisional restorations with clear aligner attachments: A technical report.

To provide a method of fabricating implant-supported provisional restorations with orthodontic attachments by digital technique. Polymethylmethacrylate (PMMA) provisional restorations are usually necessary when dental implants are serving as anchors for orthodontic treatments. For clear aligner treatment, it is possible to setup the teeth virtually and determine the final position of the implants, indicating that the provisional restorations can be also predetermined. However, attachments on PMMA restorations have a higher risk of debonding due to low bond strength. To fabricate provisional restorations with predetermined shape and position and no risk of attachment debonding immediately after implant placement, a digital workflow is introduced in this article. By combining "pick-up" technique and prefabricated monolithic PMMA provisional restorations, this technique is recommended for making implant-supported provisional restorations with integrated orthodontic attachments based on the digitally designed positions of the teeth. The present protocol describes a digital workflow of designing and manufacturing implant-supported PMMA provisional restorations with orthodontic attachments in the predetermined position of implants, which should lead to more reliable and predictable orthodontic treatment outcomes.

Efficacy of mandibular molar distalization by clear aligner treatment.

At present, the research on clear aligner of molar distalization mainly focuses on the upper jaw, while the research on mandibular molars is few.This study aims to evaluate the therapeutic effect of mandibular molars distalization with clear aligner via cone beam CT (CBCT) and Dolphin software. Twenty cases of mandibular molars with clear aligner were included according to the inclusion and exclusion criteria. CBCT was taken before treatment (T0) and when the first molar was moved in place (T1). Dolphin software was used to measure the effectiveness of molar distalization. Three-dimensional changes in direction and the impact on the incisors and facial soft and hard tissues were evaluated. The effective rates of crown and root distalization of the second and first mandibular molars were 74%, 49%, and 71%, 47%, respectively. The second and first molars were both the distal buccal cusp with the largest distalization [(2.15 ± 0.91) mm and (1.85±1.09) mm], respectively, with significant difference between the T0 and T1 (P<0.05). The second and first molars were accompanied by depression, distal tilt, and buccal tilt with 1.06 mm, 2.10°, 2.27°, and 0.91 mm, 1.62°, and 1.91°, respectively, with significant differences between the T0 and T1 (all P<0.05). There was no obvious difference between men and women. The mandibular central incisor showed a lip-side movement of 1.02 mm, a depression of 0.82 mm, a mesial incline of 0.66°, and a crown-lip torque of 1.51° after molar distalization, with significant differences between the T0 and T1 (all P<0.001). Only the lower lip thickness increased by 0.1 cm, the length of the lower lip increased by 0.1 cm, and the ANS-ME (distance from anterior nasal spine to submental point) decreased by 0.13 cm, with significant differences between the T0 and T1 (all P<0.05). Clear aligner can effectively move mandibular molars farther, the crown is more effective than the root, and it is tilted. The second mandibular molar is more effective than the first mandibular molar in its distant displacement and three-dimensional changes. Molar distalization causes minor changes in mandibular incisors and facial soft and hard tissues.

Taxonomic Analysis of Oral Microbiome during Orthodontic Treatment.

Background Orthodontic appliances induce significant changes in the oral microbiome, but this shift in microbial composition has not been well established by the available evidence yet. Objectives To perform a systematic review of existing literature in order to assess the taxonomic microbial changes in orthodontic patients during Fixed Appliance Treatment (FAT) and Clear Aligner Treatment (CAT), using next-generation sequencing (NGS) technique of the bacterial 16S rRNA gene. Search Methods and Selection Criteria. The search for articles was carried out in PubMed, including articles published in English until May 2021. They included every human study report potentially relevant to the review. Data Collection and Analysis. After duplicate study selection and data extraction procedures according to the PICOS scheme, the methodological quality of the included papers was assessed by the Swedish Council on Technology Assessment in Health Care Criteria for Grading Assessed Studies (SBU) method. Results The initial search identified 393 articles, 74 of which were selected by title and abstract. After full-text reading, six articles were selected according to inclusion criteria. The evidence quality for all the studies was moderate. Conclusions Orthodontic treatment seems to transiently affect the composition of subgingival microbiome, although not salivary, maintaining a stable microbial diversity. Different results were found in the shift of microbiome between plaque and saliva, depending on the type of orthodontic treatment. This review should be interpreted with some caution because of the number, quality, and heterogeneity of the included studies.

English

BACKGROUND Clear aligners are orthodontic devices that are transparent, a plastic used to correct malaligned teeth. Here patient wears a series of customized clear, removable aligners that gradually move the teeth to the desired position. The clear aligner system is a modern adaptation of the systems described since the middle of the 20th century, therefore there were different devices and philosophies that have led to its creation and the system has evolved a lot over the decades. Clear aligner therapy has been a part of the orthodontic practice for years, but, popularity was increased since the introduction of Invisalign appliances (Align Technology) in 1998. There are almost 27 different clear aligner products currently on offer for orthodontic treatment. Nowadays, more people prefer clear aligner treatment because it is aesthetically superior to brackets and lingual orthodontics. The superiority of clear aligners lies in their aesthetics. The optical properties of the clear aligner material play a major role in aesthetics. The rising demand among adult patients for “invisible” orthodontic treatment has led to an exponential growth in the clear aligner market. Indeed, these aligners have a low aesthetic impact, as well as being able to effectively and progressively guide the teeth into their programmed positions. They are also removable and therefore do not hamper oral hygiene maintenance, in turn reducing the risk of white spots, caries, gingivitis and periodontal disease. All the materials do not possess the same chemical composition. The properties change before and after wear. In this article, we bring out the different materials used for the manufacture of clear aligners and their various properties. KEY WORDS Clear Aligners, Optical Properties, Thermoplastic Material, Mechanical Properties

Microbiological Changes during Orthodontic Aligner Therapy: A Prospective Clinical Trial

The purpose of this study is to assess the variations induced by Clear Aligner Treatment (CAT) on the periodontal status and microbiological composition of oral microbiota. A total of 20 orthodontic patients were submitted to professional oral hygiene and, subsequently, underwent CAT (Group one, trials). A total of 20 non orthodontic patients (Group two, controls) remained untreated after oral hygiene. At T0 (baseline) and T1 (after 2 months), the participants were clinically examined for Probing Pocket Depth (PPD), Bleeding on Probing (BOP) and Plaque Index (PI), and microbiological tests were performed to detect bacteria of the red and orange complexes as well as the presence of Aggregatibacter actinomycetemcomitans. No significant inter- or intra-group differences were shown neither for PPD, PI and BOP (p &gt; 0.05), nor for bacteria expressed in copies/microlitre or in percentages (p &gt; 0.05). The only significant difference was assessed from T0 (baseline) to T1 (2 months) in both groups and is related to the total bacteria count increase. However, this parameter encompasses all the bacteria of the common oral microbiota, thus, not representing a significant result from a clinical point of view. Despite the limitations of this study, CAT does not significantly affect periodontal and microbiological parameters with respect to untreated patients for the first two months of therapy.

Orthodontic treatment with clear aligners and enamel remineralization in adolescents

Relevance. The effectiveness of the new remineralizing agent PRESIDENT®PROFI REM "MINERALS GEL" was assessed at different stages of clear aligner orthodontic treatment in adolescents with reduced enamel resistance.Materials and methods. PRESIDENT®PROFI REM "MINERALS GEL" was evaluated in a one-month open, single center, non-comparative study where 20 adolescents took part (mean age 14.9 ± 1.1 years).Results. OHI-S decreased by 24.75%, PMA and ERT reduced by 44.33% and 17.11% respectively, after one month of the orthodontic treatment with clear aligners and simultaneous use of the remineralizing gel. The pH in the mixed saliva increased from 6.97 ± 0.16 to 7.69 ± 0.11, calcium went up by 48.5%, and the total antioxidant activity decreased by 29.36% (according to the mixed saliva biochemical parameters). The OHIP-14 questionnaire revealed that the quality of life decreased in 75% of adolescent patients during the orthodontic treatment with aligners due to "communication problems". The quality of life was significantly higher during the aligner treatment with simultaneous remineralizing therapy than during the conventional treatment with fixed appliances (4.25 ± 0.86 points in the aligner group versus 7.05 ± 1.16 points – the brackets group).Conclusions. The remineralizing gel PRESIDENT®PROFI REM "MINERALS GEL" has an anti-plaque and mineralizing effect. The quality of life is significantly higher during the clear aligner treatment with simultaneous remineralizing therapy than during the conventional treatment with fixed appliances.

Information on the Internet about clear aligner treatment-an assessment of content, quality, and readability.

PurposeThe goal was to evaluate the content, quality, and readability of the information available about clear aligner treatment on the Internet.Materials and methodsThe search terms “aligner,” “clear aligner,” and “Invisalign” (Align Technology, Tempe, AZ, USA) were analyzed in three search engines (Google [Google LLC, Mountain View, CA, USA], Bing [Microsoft, Redmond, WA, USA], and Yahoo [Yahoo, Sunnyvale, CA, USA]). The first 50 websites for each keyword in each search engine were screened. Duplicate websites, advertisements, links to scientific articles, videos, and other irrelevant websites were excluded. The quality of the remaining websites was analyzed using the DISCERN and Journal of American Medical Association (JAMA) benchmark instruments together with the Health on the Net code (HONcode, Health On the Net Foundation, Geneva, Switzerland). The readability of the websites was evaluated by the Flesch Reading Ease Score (FRES) and Flesch–Kincaid Grade Level (FKGL). Statistical analyses were performed by one-way analysis of variance, Kruskal–Wallis and Fischer’s exact tests, with p < 0.05 accepted to be statistically significant.ResultsAmong 111 evaluated websites, most belonged to multidisciplinary dental clinics (n = 49; 44.2%), followed by aligner companies (n = 26; 23.4%), orthodontists (n = 26; 23.4%), and professional organizations (n = 10; 9%). The mean DISCERN score (sections 1 and 2) for all websites was 29.95/75. The average FRES and FKGL were 55.77 and 9.74, respectively. Professional organization websites had significantly higher DISCERN scores than others (p < 0.001), and together with multidisciplinary dental clinic websites, they showed better compliance with JAMA benchmark criteria. Professional organization websites’ FRES and FKGL were also higher than other websites (p > 0.05).ConclusionsOverall, the quality of web-based information about clear aligners was poor and the readability of the data was insufficient. Websites presenting high-quality data with better readability are needed for potential aligner patients.

Treatment of mild Class II malocclusion in growing patients with clear aligners versus fixed multibracket therapy: A retrospective study

ObjectiveTo compare the dental and skeletal effects of intermaxillary elastics on the correction of mild Angle's Class II division 1 malocclusion with clear aligner treatment (CA) versus fixed multibracket (FMB) in growing patients.Settings and sample populationThe study sample consisted of 49 consecutively patients (mean age ± SD 12.9 ± 1.7 years), 32 females and 17 males referred from the School of Orthodontics of the University of Bratislava Comenius (Slovakia). All patients were treated with a non‐extraction orthodontic treatment, 25 with FMB and 24 with CA.MethodsThe cephalometric analysis was performed at the beginning (T0) and the end of the treatment (T1). The t test for unpaired data was carried out to compare cephalometric values at T0 and changes at T1‐T0 between the two groups. The level of significance was set as P < .0035.ResultsThe two groups showed no statistically significant differences (ANPg = −0.1°; P = .762) in the correction of the sagittal intermaxillary relation. The analysis of vertical skeletal changes showed no statistically significant effects on mandibular inclination (SN/MP = 0.1°; P = .840). The two treatments had a statistically significant and clinically relevant difference in controlling the inclination of the lower incisors (L1/GoGn = 4.8°, CAG = −0.5°± 3.9°; FMB = 4.3°± 5.8°; P < .001).ConclusionsClass II elastics combined with CA and FMB produce a similar correction on sagittal discrepancies in growing patients. CA presented a better control in the proclination of the lower incisors. CA and elastics might be a good alternative in the correction of mild Class II malocclusion in cases where a proclination of lower incisors is unwanted.

Maxillary sagittal expansion in an adult patient

Relevance. Skeletal Class III malocclusion is known to be one of the most difficult malocclusions to correct. Nonsurgical treatment of Class III in adults is a challenge; however, this patient refused surgery. A treatment method with Fixed Anterior Growth Guidance Appliance (FAGGA) was investigated in the study.Materials and methods. This case report presents a 37-year-old woman with skeletal Class III malocclusion for maxillary deficiency. As the patient didn’t agree to surgery, she was treated by Fixed Anterior Growth Guidance Appliance, followed by 3D SMILE® clear aligners. Fixed Anterior Growth Guidance Appliance was used initially. After 4 months, the appliance was removed and clear aligner treatment was initiated. Post-treatment radiographs showed improvement.Results. Intraorally, in the upper arch, a total of 4.00 mm of space were gained (about 2.00mm distal to each canine). The post-treatment cephalometric analysis showed a skeletal A-P Class I, the Upper incisor inclination to the optic plane was not significantly altered, ANS — antArc was improved by 1.5mm, the Effective Length of the Premaxilla increased by 2.6mm, U1 — ANS’ decreased by 1.7mm, Incisor mandibular plane angle (IMPA) autonomously improved by 11 degrees.Conclusions. Maxillary deficiency was corrected successfully with the Fixed Anterior Growth Guidance Appliance. The treatment is being continued by 3D SMILE® clear aligners. The goal was achieved despite the patient’s age and nonsurgical treatment.

Behavior of Primary Human Oral Keratinocytes Grown on Invisalign® SmartTrack® Material

Orthodontic clear aligner treatment is gaining tremendous popularity. The world market leader is Align Technology® and its product Invisalign®. Although numerous patients are treated with Invisalign® aligners, only little is known about the cellular effects of aligner material on oral epithelial cells. In the present study, we aimed to investigate the effects of SmartTrack® clear aligner material on directly cultured primary human oral keratinocytes (HOKs). Cell morphology and behavior were investigated by scanning electron microscopy and bright field microscopy. Aligner effects on viability were detected by cell-counting-kit (CCK)-8 and live/dead staining. Gene expression of several inflammatory and barrier proteins was assessed by qPCR. Cells cultured on tissue culture plastic served as control. Cell proliferation/viability was significantly lower in cells cultured on aligner material (p &lt; 0.05) in comparison to control. Live/dead staining did not reveal an increase in the number of dead cells on aligner surfaces. After two and seven days of incubation, interleukin (IL)-6 expression decreased, and IL-8 expression increased in HOKs cultured on aligner surfaces. The expression of intercellular adhesion molecule 1 (ICAM-1) significantly decreased after seven days. Gene expression of epithelial barrier markers showed that integrin (ITG)-α6 significantly decreased after two and seven days. A significant decrease in ITG-β4 and E-cadherin expression levels compared to control could only be seen after seven days. We did not find any cytotoxic effect, but alterations in the cell’s barrier functions and inflammatory reaction were obvious. Clinical studies are required to give further insights into clinical reactions on the underlying aligner material of this quickly expanding orthodontic appliance.

The 50 most-cited articles on clear aligner treatment: A bibliometric and visualized analysis

Research on clear aligner treatment (CAT) has increased in recent years. In this study, we aimed to perform a bibliometric and visualized analysis to identify and critically assess the 50 most highly cited articles on CAT. Web of Science was selected as a data source and consulted until March 2020 to identify all articles potentially relevant to the analysis. All the eligible articles were collected until 50 manuscripts were listed. Article-based parameters, journal-based parameters, and author-based parameters were registered to perform the bibliometric analysis. Keywords were automatically harvested from the selected articles to implement the visualized analysis. The search identified a total of 378 articles; the total number of citations of the selected articles varied from 15 to 112. The average number of citations per year varied from 1.15 to 13.83. The predominant study design was clinical (31.7%). Over the 15 journals in which the most cited articles were published, the American Journal of Orthodontics and Dentofacial Orthopedics published the majority of those included in the list (14) and also received the greatest number of citations (671). A total of 195 authors contributed to the 50 most cited articles; a significant portion of them (26) were unaffiliated with academic institutions. A total of 184 keywords were gathered from the article list. The number of citations on CAT is expected to grow steadily in parallel with the rising number of research projects. The present work identifies the most influential articles on CAT and their characteristics, placing emphasis on the journals, the authors, and the topics addressed.

Maxillary arch development with Invisalign system.

To evaluate tooth movements during maxillary arch expansion with clear aligner treatment. The study group included 28 subjects (16 females, 12 males, mean age 31.9 ± 5.4 years) collected prospectively from January 2018 to May 2019. Inclusion criteria were European ancestry, posterior transverse discrepancy of 3-6 mm, permanent dentition stage, presence of second permanent molars, mild or moderate crowding, and good compliance with aligners. Treatment protocol included nonextraction strategies, application of Invisalign clear aligner system, and no auxiliaries other than Invisalign attachments. Linear and angular measurements were performed before treatment (T1), at the end of treatment (T2), and on final virtual models (T2 ClinCheck). A paired t-test was used to compare T2-T1 and T2-T2 ClinCheck changes. The level of significance was set at 5%. Statistically significant differences were found for all measurements, except for ones at the upper second molars. The greatest increase in maxillary width was detected at the upper first and second premolars: +3.5 mm for the first premolar and +3.8 mm for the second premolar at T2. Comparison of T2-T1 angular outcomes showed statistically significant changes in the inclinations of all teeth except for the second permanent molars. T2-T2 ClinCheck showed significant differences for both linear and angular measurements for maxillary canines, resulting in poor predictability. Maxillary arch development revealed a progressive reduction of the expansion rate and buccal tipping in the anterior, lateral, and posterior regions, with the greatest net increase at the first and second premolars. Clinical attention should be paid to maxillary canine movements, and overcorrection should be planned for them during dentoalveolar expansion.

Outcomes of clear aligner treatment with and without Dental Monitoring: A retrospective cohort study

Theeffects of Invisalign clear aligner treatment with and without Dental Monitoring (DM) were compared for treatment duration, number of appointments, refinements and refinement aligners, and accuracy of Invisalign in achieving predicted tooth positions (aligner tracking). The null hypothesis was that there are no differences between Invisalign with and without DM in these parameters. A sample of 90 consecutively treated Invisalign patients (45 control, 45 DM) fitted the inclusion and exclusion criteria. Treatment duration, number of refinements, number of refinement aligners, time to first refinement, number of appointments, number of emergency visits, and accuracy of predicted tooth movement were observed for differences. The 2 groups were homogeneous (P>0.05) for sample size, age, gender, Angle classification, maxillary and mandibular irregularity index, and the number of initial aligners. There was a significant (P=0.001) reduction in the number of appointments by 3.5 visits (33.1%) in the DM group. There was also a significant (P=0.001) reduction in the time to the first refinement (1.7months) in the DM group. Compared with Invisalign predicted tooth positions, actual tooth positions were statistically (P<0.05) more accurate for the DM group for the maxillary anterior dentition in rotational movements and mandibular anterior dentition for buccal-lingual linear movement. Invisalign therapy without DM was closer to predicted tooth positions for the maxillary posterior dentition for the tip. None of these differences surpassed the clinically significant thresholds (>0.5mm or>2°); however, the DM group achieved this in 1.7 fewer months. DM with Invisalign therapy resulted in a reduced number of appointments by 3.5 visits (33.1%). The DM group also achieved a clinically similar accuracy in obtaining predicted tooth movements compared with the control group in 1.7 fewer months, indicating improved aligner tracking in the DM group.

How well do integrated 3D models predict alveolar defects after treatment with clear aligners?

To evaluate the accuracy of integrated models (IMs) constructed by pretreatment cone-beam computed tomography (pre-CBCT) in diagnosing alveolar defects after treatment with clear aligners. Pre-CBCT and posttreatment cone-beam computed tomography (CBCT) scans from 69 patients who completed nonextraction treatment with clear aligners were collected. The IMs comprised anterior teeth in predicted positions and alveolar bone from pre-CBCT scans. The accuracy of the IMs for identifying dehiscences or fenestrations was evaluated by comparing the means of the defect volumes, absolute mean differences, and Pearson correlation coefficients with those measured from post-CBCT scans. Defect prediction accuracy was assessed by sensitivity, specificity, positive predictive values, and negative predictive values. Factors possibly affecting changes in mandibular alveolar defects were analyzed using a mixed linear model. The IM measurements showed mean deviations of 2.82 ± 9.99 mm3 for fenestrations and 3.67 ± 9.93 mm3 for dehiscences. The absolute mean differences were 4.50 ± 9.35 mm3 for fenestrations and 5.17 ± 9.24 mm3 for dehiscences. The specificities of the IMs were higher than 0.8, whereas the sensitivities were both lower (fenestration = 0.41; dehiscence = 0.53). The positive predictive values were unacceptable (fenestration = 0.52; dehiscence = 0.62), and the overall reliability was low (<0.80). Molar distalization and proclination were positively correlated with significant increases in alveolar defects at the mandibular incisors after treatment. Alveolar defects after clear aligner treatment cannot be simulated accurately by IMs constructed from pre-CBCT. Caution should be taken in the treatment of crowding with proclination and molar distalization for the safety of alveolar bone at the mandibular incisors.

Frequency of white spot lesion with clear aligner: a systematic review

The aim of this systematic review was to evaluate the incidence of white spot lesion with clear aligners. Decalcification or whit spot lesion (WSL) is a white opacity seen on smooth surfaces because of retention of bacterial plaque. Recently, there has been an increase in the number of adults seeking orthodontic treatment that is both more esthetic and more comfortable. However, there are few studies reporting the prevalence of WSL with clear aligners. Clear aligner treatment provides various advantages in maintaining oral hygiene; therefore, this systematic review was conducted of all studies that reported the frequency of white spot lesion with clear aligner therapy. Literature research was conducted on different databases electronically by using specific inclusion and exclusion criteria, two independent investigators performed data extraction and analysis. Total 9,949 records were identified. However, only three articles met the criteria that were included in this systematic review. The quality assessment for included studies showed that all three studies had low quality. It was concluded that there is an increase in WSL after clear aligner therapy according to the available evidences, however, this increase is less than that reported for conventional orthodontic fixed appliances.

An objective system for appraising clear aligner treatment difficulty: clear aligner treatment complexity assessment tool (CAT\u2013CAT)

BackgroundRecent years have witnessed a remarkable evolution of clear aligner technology and clear aligners are becoming more and more versatile in treating orthodontic patients. The aim of this study was to develop an objective evaluation system for assessing clear aligner treatment difficulty.MethodsA total of 120 eligible patients (100 patients for developing and testing the evaluation system and 20 patients for validating this system) were recruited in this retrospective cross-sectional study. Based on clinical data (dental models, radiographs and photographs), complexity levels of cases were evaluated by two experts and regarded as the gold standard. Difficulty scores were determined through an evaluation system encompassing three domains (dental model analysis, radiographic examinations and clinical examinations). The reliability of the evaluation system was examined through analyzing the agreement between complexity levels and difficulty scores. Moreover, multivariable linear regression test was used to examine the independent association of each variable (e.g. overbite and crowding) with the complexity level.ResultsThe results revealed that the assessment of treatment difficulty by this objective evaluation system substantially matched the gold standard (R2 = 0.80). The multivariable regression test revealed that complexity level was significantly associated with difficulty score (p < 0.001), age (p = 0.015), tooth extraction (p < 0.001), treatment stage (p < 0.01) and the number of difficult tooth movement (p = 0.005). This objective evaluation system elaborated in this study was viable and reliable in appraising clear-aligner treatment difficulty in clinical practice.ConclusionsWe suggest orthodontists and general practitioners use this objective evaluation system (CAT-CAT) to appraise clear aligner treatment difficulty and to select appropriate clear aligner patients.

Periodontal disease treated with clear aligner

Clear aligner is a kind of removable orthodontic appliance, which designed and manufactured using digital technology. It is more and more widely used in adults and patients with periodontal disease. Clear aligner treatment in patients with moderate and mild periodontal diseases can achieve good result. Meanwhile, there are still risks in the clear aligner treatment in patients with severe periodontal diseases, so it is necessary to strictly control the indications. Multidisciplinary treatment of complex periodontal disease is important before the start of orthodontics. The objective of orthodontic treatment in patients with periodontal disease should be made clear and the range of tooth movement must be strictly controlled. In the application of the clear aligner, the feasible target position of clear aligner should be designed. According to patient's periodontal condition, staging should be designed and the reasonable attachment should be set. The shape of the aligner should be designed to reduce the gingival stimulation. Clear aligner treatment could play an important role in multidisciplinary treatment, and improve the overall effect in patients with periodontal disease. The application of clear aligner in the treatment of periodontal diseases was discussed in various aspects, providing a reference for rational clinical use.

Vertical control in clear aligner treatment

Clear aligners are the fastest-growing appliances in this century, which are not only favored by patients, but also concerned by doctors. This article explains the significance of vertical control in orthodontic treatment, the advantages and disadvantages of vertical control with clear aligner. It also analyzes the causes of the shortcomings and how to use existing technologies and methods to make up for these shortcomings.

Extraction and non-extraction cases treated with clear aligners

Clear aligner (CA) treatment achieves therapeutic goals through digital dental models and tooth movement planning. In recent years, with the increasingly wider clinical application of CA, orthodontists are frequently faced with the important choice of tooth extraction or non-extraction in treatment planning. This article addresses the approaches of providing spaces, the importance and criteria of choosing extraction or non-extraction plans, and the strategy of using digital treatment simulation.