Clear aligner therapy informed consent forms: A quality and readability evaluation.

OBJECTIVE: The aim of the present study was to evaluate the quality and readability of content contained within clear aligner therapy (CAT) informed consent forms. METHODS: CAT informed consent forms were identified via an online search. The presence of details related to CAT-related processes, risks, benefits and alternatives in each form was recorded. A 4-point Likert type scale was used to determine the quality of content (QOC). The readability of content was evaluated with the Simple Measure of Gobbledegook (SMOG) and Flesch Reading Ease Score (FRES). RESULTS: A total of 42 forms satisfied selection criteria. Nineteen (45.2%) were authored by companies who provided aligners to patients via clinicians. The QOC regarding CAT-related treatment processes [median 2.0; IQR 0, 2] and benefits [median 2.0; IQR 1, 2] was adequate. The QOC scores regarding treatment alternatives, consequences of no treatment and relapse were poor. There was no difference (P=0.59) in the median (IQR) QOC of the informed consent forms provided by direct-to-consumer (DTC) aligner providers [10 (8.25, 16.25)] and non-DTC aligner providers [12 (10, 14)]. The median (IQR) SMOG score was 12.1 (10.9, 12.7) and FRES was 39.0 (36.0, 44.25). CONCLUSIONS: The QOC of the evaluated forms was incomplete and poor. The content was difficult to read and failed to reach recommended readability standards. Consent is unlikely to be valid if it is based solely on the content of the forms. Clinicians need to be aware of the limitations of informed consent forms for CAT particularly in relation to alternatives, prognosis, risks, and the need for long-term maintenance of results.

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

OBJECTIVE: 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. METHODS: 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. RESULTS: 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. CONCLUSIONS: 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.

Invisalign Lite: a cross-sectional investigation of orthodontist treatment-planning practices.

OBJECTIVES: To survey treatment-planning practices of orthodontists related to the Invisalign Lite clear aligner appliance (Align Technology, San Jose, Calif). MATERIALS AND METHODS: Patients satisfying inclusion and exclusion criteria and treated with Invisalign Lite were selected from a database containing more than 17,000 patients. Relevant data regarding treatment-planning practices were obtained from Align Technology's treatment-planning facility, ClinCheck, and evaluated. RESULTS: Most (n = 135; 79.9%) patients were female and had a median (interquartile range [IQR]) age of 30.5 (23.8, 43.1) years. The median (IQR) number of aligners for the sample was 23.0 (14, 28) for the maxilla and 24 (14, 28) for the mandible. Most (n = 122; 72.2%) patients required at least one additional series of aligners. More locations for interproximal reduction (IPR) were prescribed in the mandible (mean 1.91 [1.78]) than in the maxilla (1.03 [1.78]; P < .024) in the initial accepted plan of all patients. More teeth were prescribed composite resin (CR) attachments in the maxilla (P < .0001) in the initial accepted plan of all patients. Issues regarding tooth position protocols (n = 50; 53.3%) and requirement for additional IPR (n = 68; 45.3%) were reasons for treatment plan changes before acceptance of the initial treatment plan by orthodontists. CONCLUSIONS: More than 7 of 10 patients required at least one additional series of aligners after the initial series of Invisalign Lite aligners was completed. Prescription of IPR was more common in the mandible, and prescription of CR attachments was more common in the maxilla.

Assessment of the quality and accuracy of information contained within the websites of marketed orthodontic products: a cross-sectional investigation.

OBJECTIVES: To assess the quality and accuracy of information contained within the websites of providers of marketed orthodontic products. MATERIALS AND METHODS: Twenty-one websites of orthodontic appliance and adjunct (product) providers were identified. The website content was assessed via two validated quality-of-information instruments (DISCERN and the Journal of the American Medical Association [JAMA] benchmarks) and an accuracy-of-information instrument. Website content was qualitatively analyzed for themes and subthemes. RESULTS: More than half (n = 11; 52.3%) of the assessed websites contained clinician testimonials. The mean (SD) DISCERN score was 33.14 (5.44). No website recorded the minimum of three JAMA benchmarks required to indicate reliability. The most common content themes related to quality-of-life impact and treatment duration. Just 8% of the statements within the websites were objectively true. The Pearson correlation coefficient indicated that the DISCERN scores were correlated with the accuracy-of-information scores (r = .83; P < .001). CONCLUSIONS: The quality and accuracy of information contained within the websites of the providers of marketed orthodontic products was poor. The combined use of DISCERN and the accuracy-of-information instrument may help overcome the shortcomings of each. Clinicians should check the accuracy of information on orthodontic product provider websites before adding links to those websites on their own sites.

The orthodontic extraction of second premolars: The influence on airway volume.

INTRODUCTION: The extraction of second premolars and associated changes in the volume of the airway have not been previously explored. This retrospective study aimed to compare the volumetric changes of the airway preorthodontic and postorthodontic treatment in relevant extraction and control samples and to identify variables that may influence the outcome. METHODS: Cone-beam computed radiography scans of 54 patients with second premolar extraction and 59 nonextraction patients treated in a private orthodontic practice were matched for crowding. The average age for both samples was 15 years. The images were individually landmarked and measured by applying volumetric, linear, and angular parameters. The results were analyzed using repeated measures, such as variance analysis, correlation testing, and regression statistical analyses. RESULTS: There was a statistically significant increase in the airway volume for both groups (P <0.05). The difference in increase between the groups was not statistically significant. Seven variables demonstrated a collectively significant effect on changes to airway volume (F[7,112] = 38.48; P <0.001; r2 = 0.701), with 70% of the variation predicted by the variables. Multiple regression analyses indicated that changes to the area of minimum constriction (B = 32.45; t = 11.95; P <0.001) and changes to airway length (B = 94.75; t = 7.79; P <0.001) had a statistically significant effect on airway volume. CONCLUSIONS: The volume of the airway increased in both the extraction and nonextraction samples. The biggest contributors to the increase were an increase in airway length and an increase in the area of minimum constriction, which likely occurred as a result of natural growth.

Interproximal reduction in the refinement phase of Invisalign treatment: A quantitative analysis.

INTRODUCTION: Interproximal reduction (IPR) is a common adjunct to contemporary orthodontic treatment. This study aimed to carry out a quantitative analysis of IPR prescribed in the refinement phases of clear aligner therapy with the Invisalign appliance (Align Technology, San Jose, Calif). METHODS: The digital treatment plans (DTPs) of a total of 330 patients treated by 11 orthodontists were evaluated. Relevant data regarding patient age, gender, and prescription of IPR in the initial and refined DTPs were obtained from Align Technology's digital interface, ClinCheck. Computational analyses included descriptive statistics, Mann-Whitney U, and Kruskal-Wallis tests. RESULTS: Most (n = 182; 75.2%) of the 242 patients who satisfied inclusion criteria were females. The median (interquartile range [IQR]) age was 29.2 (22.1-40.2) years. More than 60% of the contact sites prescribed IPR related to the initial DTP (n = 1312; 60.4%), with 39.6% (n = 859) recorded in the refinement DTPs. A median (IQR) of 1.1 (0.6-2.1) mm of IPR was prescribed per patient in the initial DTP compared with a median (IQR) of 0.6 (0.3-1.3) mm in the refinement DTPs. The most common site for prescribed IPR in all DTPs was the mandibular anterior region. Almost half (n = 108; 44.6%) of the patients were prescribed IPR at the same contact point site more than once during treatment. CONCLUSIONS: Almost 40% of the contact points that were prescribed IPR were in the patients' refinement DTPs. Most IPR was prescribed for the anterior region of the mandible. Almost half of the patients had IPR repeatedly prescribed at the same sites during treatment.

Usage of temporary anchorage devices: A cross-cultural and cross-sectional survey of orthodontists in Australia and the UK.

INTRODUCTION: Detailed insight regarding the use of temporary anchorage devices (TAD) in Australia and the United Kingdom (UK) is lacking. The primary aim of the present cross-sectional survey was to investigate TAD usage among UK-based and Australian-based orthodontists. The secondary objectives were to compare TAD-related preferences and protocols between orthodontists in the two countries. METHODS: A pilot-tested electronic questionnaire was distributed to members of the British Orthodontic Society and the Australian Society of Orthodontists. Questions pertained to their demographic details, and current use of TADs including protocols, treatment objectives and factors influencing their use. RESULTS: A total of 192 responses were recorded (Australia: 122; UK: 70). One hundred and forty-two respondents (74.0%) reported using TADs as part of their orthodontic treatment, 77.0% in Australia (n=94) and 68.6% in the UK (n=48). Molar protraction was the most common procedure for which TADs were reportedly used (Australia: n=118; 87.2%, UK: n=36; 75.0%). "Loosening" was the most prevalent reported complication overall (n=124; 90.1%). "Confidence", "insufficient postgraduate education" and "availability of equipment" were the factors that most influenced the decision not to provide TADs. CONCLUSIONS: Most orthodontists in both countries provided TADs. TAD protocols of orthodontists in both countries were reported. Similarities and differences regarding TAD-related clinical practices and procedures, complications and factors influencing the use of TADs and reasons for not using TADs were explored. Information from the present study can provide baseline data for future related studies in each country and for comparison of TAD usage in other countries.

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

INTRODUCTION: 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). METHODS: 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. RESULTS: 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. CONCLUSIONS: 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.

Predicted overbite and overjet changes with the Invisalign appliance: a validation study.

OBJECTIVES: To investigate whether the predicted changes in overbite (OB) and overjet (OJ) in Align Technology's (Santa Jose, Calif) digital treatment plan for the prescribed course of treatment with the Invisalign appliance were consistent with those same changes in OB and OJ measured with the Geomagic Control X (Geomagic US, Research, Triangle Park, NC) metrology software system. MATERIALS AND METHODS: Geomagic Control X software was used to determine OB and OJ differences between the pretreatment and predicted outcome. STL files for patients satisfying inclusion criteria and undergoing nonextraction orthodontic treatment with the Invisalign appliance. The differences were compared, using the Bland-Altman analysis, to the corresponding data provided by Align Technology's digital treatment-planning interface, ClinCheck. RESULTS: Data regarding 76 adult patients who satisfied strict inclusion criteria were assessed. The Shapiro-Wilks test indicated normality (P > .05). The Bland-Altman analysis showed high levels of agreement between the two measurements, with a bias range of -0.131 to 0.111 for OB and -0.393 to 0.03 for OJ recorded. CONCLUSIONS: Clinicians and researchers can be confident that measurement data provided by Invisalign's ClinCheck digital treatment-planning facility concerning OB and OJ changes from the initial to the predicted treatment outcome are valid.

Predicted and achieved overjet and overbite measurements with the Invisalign appliance: a retrospective study.

OBJECTIVES: To determine whether achieved outcome regarding overjet and overbite matched the predicted outcome following treatment with Invisalign (Align Technology, San Jose, Calif) aligner appliances. MATERIALS AND METHODS: Data including pretreatment, predicted and achieved overjet, and overbite measurements provided by Align's digital treatment facility, ClinCheck Pro, were evaluated. Descriptive statistics, Mann-Whitney U-test, and Wilcoxon rank-sum intraclass correlation (ICC) test results were calculated. RESULTS: From an initial sample of 600, 355 adult patients satisfied the inclusion and exclusion criteria. ICC scores for data input were excellent. Median (interquartile range [IQR]) age was 30.14 (23.33, 39.92) years and most (n = 259; 72.95%) were women. Almost one-third (n = 101; 28.45%) had undergone extraction as part of their treatment. More aligners were prescribed in the initial digital treatment plan for patients (median, 44; IQR: 35, 51.5; minimum, 17; maximum, 92) undergoing extractions as part of their orthodontic treatment than those who were not (median, 24; IQR: 18.25, 32; minimum, 13; maximum, 85) (P < .0001). Planned changes in overjet differed significantly from achieved outcomes (P < .001). Planned increases in overbite resulted in up to more than twice (222.72%) as much increase than predicted. Planned reduction of overbite achieved 8.69% of its predicted reduction in extraction cases. CONCLUSIONS: Achieved overjet and overbite measurements differed significantly from the predicted outcomes at the end of an initial sequence of aligners. Planned increases in overbite resulted in greater overbite correction than predicted, particularly in extraction cases. Planned overbite reduction was challenging, especially in patients with extractions.

Influence of second premolar extractions on the volume of the oral cavity proper: a control comparative cone-beam computed tomography volumetric analysis study.

OBJECTIVES: To compare the pre- and postorthodontic treatment volumetric changes of the oral cavity proper (OCP) in extraction and nonextraction patients and to identify influencing variables. MATERIALS AND METHODS: Pre- and posttreatment cone-beam computed tomography (CBCT) scans of patients undergoing orthodontic treatment with fixed labial appliances and who satisfied the inclusion criteria were individually landmarked. Linear, angular, and volumetric measurements were determined. Descriptive statistics, repeated measure analyses of variance, correlations, and stepwise regression statistical analyses were applied. RESULTS: The CBCT scans of 54 patients who underwent the extraction of second premolars and/or extraction of second primary molars associated with agenic second premolars, and 59 nonextraction patients matched for crowding, were assessed. The mean age for both groups was 15 years. There was a statistically significant increase in the volume of the OCP for both the extraction and nonextraction groups, with the nonextraction group demonstrating a larger increase in the volume of the OCP. Gender, age, changes in mandibular and maxillary arch length, and changes in mandibular and maxillary intermolar width all influenced the change in the OCP volume. CONCLUSIONS: The volume of the OCP increased in growing patients with and without the extraction of the second premolars and/or extraction of second primary molars associated with agenic second premolars. Patients who did not have extractions as part of their orthodontic treatment demonstrated a greater overall increase in OCP volume.

Clear aligner therapy practice among orthodontists in the United Kingdom and the Republic of Ireland: A cross-sectional survey of the British Orthodontic Society membership.

OBJECTIVE: To investigate clear aligner therapy (CAT) practice among orthodontists in the British Orthodontic Society (BOS). DESIGN: A cross-sectional online survey. METHODS: An electronic survey was distributed to members of the BOS in 2022. The survey comprised questions regarding respondent demographics, general use of CAT, the choice of proprietary CAT appliances, CAT planning, case selection, treatment protocols and orthodontist-reported CAT problems. RESULTS: Overall, 233 (19.5%) responses were received with the majority (n = 121, 53.1%) being female. Most respondents reported practising in England (n = 171, 74.7%). The majority (n = 177, 77.3%) indicated that they used CAT in their practice, with 48.1% (n = 81) treating 1-20 patients with CAT annually. The most frequently prescribed CAT system was Invisalign (n = 138, 81.2%). One to three changes to the initial digital treatment plan were made by 72.9% (n = 121) with final tooth positions being the most common reason for adjustment (64.4%). Most (n = 97, 60.3%) rarely or never performed premolar extractions with CAT. Of the respondents, 23 12.7%) reported that they always or mostly used a remote monitoring system in conjunction with CAT, with a wide range of aligner change protocols reported. The median number of months required to complete non-extraction CAT reported by the respondents was 12. Most respondents (n = 77, 51.7%) did not feel that CAT provides superior outcomes compared with fixed appliance therapy. CONCLUSION: CAT practice varied widely among the surveyed orthodontists. A predilection for the use of Invisalign and utility in less severe cases was noted.

The genetic and environmental contributions to variation in the permanent dental arch form: a twin study.

OBJECTIVE: The objective of this study was to examine the relative contributions of genetic and environmental influences on variation in dental arch form in individuals who have largely completed their craniofacial growth. MATERIAL AND METHODS: The subjects of this study comprised dental casts of 50 monozygotic twins and 24 dizygotic twins from the collection of records of twins housed at the Adelaide Dental School, Australia. The subjects were of Western European descent, with an average age of 20.93 ±â€…5.58 years. Dental casts were scanned using a 3D scanner to analyse the dental arch form. Landmark-based inter-arch and intra-arch measurements were performed. Structural equation modelling was employed to analyse the quantitative data using the normal assumptions of the twin model. RESULTS: Genetic modelling revealed that additive genetic and unique environmental factors best explained the observed variation for all occlusal traits measured, except for mandibular intercanine width. High heritability was observed for most intra-arch occlusal variables (0.61-0.85) including the maxillary and mandibular intercanine and intermolar widths, arch depth and perimeter. In contrast, moderate heritability was found for inter-arch occlusal variables (0.52-0.59) such as overjet and overbite. Sexual dimorphism was evident, with males displaying larger posterior arch width than females (P < 0.05). LIMITATIONS: Our sample was limited to individuals of Western European ancestry. CONCLUSION: The predominant source of occlusal variation within this group of Australian twins of Western European descent was controlled by genetic effects, and most were highly heritable. Generally, intra-arch occlusal variables showed greater heritability compared with inter-arch occlusal variables.

Tooth agenesis: An overview of diagnosis, aetiology and management.

Patients with one or more developmentally absent teeth are routinely encountered in dental practice. Tooth agenesis can be associated with significant functional, aesthetic and psycho-social problems. The present article provides an overview of the prevalence and aetiology of tooth agenesis, as well as the condition's clinical characteristics and management options with reference to the evidence base. A timely diagnosis can facilitate the appropriate planning and management which might not be straightforward, and patient care will likely require multi- and inter-disciplinary input. It is critical that dental care practitioners are aware of the clinical characteristics and management options for tooth agenesis.

Evaluation of orthodontic retention and retainer content on the Reddit social media website.

BACKGROUND: Social media can provide insight into patient experiences with health care. The aim of this study was to evaluate the content regarding orthodontic retention and retainers on the social media website, Reddit. METHODS: A systematic search for relevant content submitted over a 12-month period on the Reddit forum, r/braces, was conducted. Qualitative analysis of the initial posts for themes and subthemes was conducted by two investigators. Responding comments to the initial posts were assessed for supportiveness for each initial poster and alignment with the evidence-base. Quantitative assessment was via descriptive statistics. RESULTS: A total of 271 initial posts and 984 comments satisfied the inclusion/exclusion criteria. All initial posts were by patients. Just 1.12% (n = 11) of the comments appeared to be provided by oral health professionals. Most initial posts were negative (50.18%; n = 136), and most comments were positive (70.42%; n = 693). Alignment with the evidence-base was high among the comments (67.89%; n = 668). Eight main themes were identified with concerns regarding the negative impact of retention and retainers on quality of life, compliance with retention protocols and relapse commonly expressed. Concern regarding fear of relapse when waiting for the initial or renewal of retainers was a novel finding. More negative sentiments about orthodontists were expressed than positive. CONCLUSIONS: Reddit is a supportive and reliable environment for patients regarding orthodontic retention and retainers. The content evaluation suggested deficiencies in communication processes between clinicians and patients. Greater engagement of the orthodontic profession in the provision of supportive and evidence-based information on an individual patient basis and through appropriate information channels is required.

The predictability of maxillary curve of Spee leveling with the Invisalign appliance.

OBJECTIVES: To evaluate the predictability of the Invisalign appliance (Align Technology, Santa Clara, Calif) in leveling the maxillary curve of Spee (COS). MATERIALS AND METHODS: A retrospective sample of adult subjects treated with the Invisalign appliance between 2013 and 2019 were selected. Patients were treated nonextraction in the maxillary arch and had either Angle Class I or II malocclusions with a minimum of 14 aligners with no bite ramps. Initial, predicted, and actual outcomes were analyzed with Geomagic Control X software (version 2017.0.3; 3D Systems, Cary, NC). RESULTS: A sample of 53 cases satisfied inclusion/exclusion criteria. Paired t-tests demonstrated a significant difference between mean predicted and actual maxillary COS leveling with a shortfall of 0.11 mm (SD = 0.37; P = .033). Planned intrusion tended to be more accurate posteriorly with an overexpression of 117% for the first molars. Planned extrusion was the least accurate, with the mid-arch demonstrating expressions of -14% to -48%. These teeth intruded despite a prescribed extrusive movement. CONCLUSIONS: The Invisalign appliance did not accurately predict maxillary COS leveling. Planned intrusive movements were overcorrected, and planned extrusive movements were either undercorrected or resulted in intrusion. This effect was most apparent for the upper first molar, which expressed 117% and -48% of planned intrusion and extrusion, respectively.

The predictability of maxillary curve of Wilson leveling with the Invisalign appliance.

BACKGROUND: This retrospective study aims to evaluate the predictability of the Invisalign appliance (Align Technology, Santa Clara, CA) in leveling the maxillary curve of Wilson (COW). METHODS: 53 adult subjects treated by orthodontists who are experienced Invisalign providers, between 2013 and 2019 were selected. All patients had either Angle Class I or II malocclusions and were treated by non-extraction in the maxillary arch with a minimum of 14 Invisalign aligners with no bite ramps or auxiliaries. Initial, predicted, and actual outcomes were analyzed with Geomagic Control X software (3D systems, Rock Hill, SC; Version 2017.0.3). RESULTS: Despite planning mean (SD) COW leveling of 0.25 mm (1.91), the curve became significantly more pronounced by 1.15 mm (0.85) (P < .001). There was a significant overexpression of buccal inclinations between mean prescribed versus actual values from 0.10 mm (0.39) (P = .007) to 0.29 mm (0.47) (P < .001) from the first premolars to the second molars, respectively. These differences were more pronounced posteriorly. The differences between the predicted and actual arch width values were underexpressed for all teeth except the second molars; a mean underexpression between 0.28 mm (0.92) and 0.60 mm (1.14). The second molars were the only teeth to overexpress with a mean of 0.42 mm (1.02). CONCLUSIONS: Overall mean maxillary COW was not predictably controlled with Invisalign. The appliance tends to overexpress the buccal crown tip regardless of prescribed direction, especially posteriorly. Arch expansion was underexpressed at all levels of the arch except for second molars which overexpressed by almost four times.

Treatment planning protocols with the Invisalign appliance: an exploratory survey.

OBJECTIVES: To investigate the changes made by orthodontists to the initial digital treatment plan (DTP) regarding the Invisalign appliance provided by Align Technology until acceptance of the plan by the orthodontist. MATERIALS AND METHODS: The DTPs of subjects who underwent treatment with the Invisalign appliance and satisfied inclusion criteria were assessed to determine the number of DTPs and changes regarding prescription of aligners, composite resin (CR) attachments, and interproximal reduction (IPR) between the initial DTP and the accepted plan. Statistical analyses were calculated via GraphPad Prism 9.0 (GraphPad Software Inc., La Jolla, Calif). RESULTS: Most of the 431 subjects who satisfied inclusion/exclusion criteria were female (72.85%). More DTPs were required for subjects who had orthodontic extractions (median [interquartile range; IQR]: 4 [3, 5]) compared with those who did not (median [IQR]: 3 [2, 4], P < .0001). The median (IQR) overall number of aligners prescribed in the accepted DTP (30 [20, 39]) was greater than the initial DTP (30 [22,41], P < .001). The number of teeth used for CR attachments increased from the initial to the accepted DTP (P < .001). More CR attachments were observed in extraction treatment DTPs with a prescribed 2-week aligner change protocol compared with nonextraction treatment (P < .0001). The number of contact points with prescribed IPR increased between initial and accepted DTPs (P < .0001). CONCLUSIONS: Significant changes regarding DTP protocols were observed between the initial and accepted DTPs and between nonextraction and extraction-based CAT.

Digital treatment planning and clear aligner therapy: A retrospective cohort study.

OBJECTIVE: To investigate the total number of digital treatment plan (DTPs) and aligners manufactured for clear aligner therapy (CAT) by Invisalign® from initial treatment planning to the completion of CAT. DESIGN: A retrospective cohort study. MATERIAL AND METHODS: A total of 30 patients, from each of 11 experienced orthodontists, who commenced treatment over a 12-month period, were assessed regarding the number of DTPs and aligners prescribed from initial planning to completion of CAT. Patients were categorised according to the number of aligners prescribed by the initial DTP into mild (<15), moderate (15-29) or severe (>29). RESULTS: After the application of inclusion/exclusion criteria, 324 patients (71.9% women; median age = 28.5 years) undergoing non-extraction treatment with the Invisalign® appliance were assessed. The median number of initial DTPs was 3 (interquartile range [IQR] = 2, 1-9) per patient before acceptance by the orthodontist. Most (99.4%) patients required a refinement phase with a median of 2 (IQR = 2, 2-7) refinement plans recorded. A total of 9135 aligners per dental arch, was prescribed in the initial DTP of the 324 patients assessed and 8452 in the refinement phase. The median number of aligners per dental arch prescribed from the initial DTP was 26 (IQR = 12, 6-78) and from the refinement plans was 20.5 (IQR = 17, 0-132). CONCLUSION: A median of three initial DTPs and two refinement plans were required for patients undergoing non-extraction treatment with the Invisalign® appliance. Patients were prescribed almost double the number of aligners initially predicted to manage their malocclusion.

Evaluation of the predicted vs. achieved occlusal outcomes with the Invisalign® appliance: A retrospective investigation of adult patients.

INTRODUCTION: The aim of this study was to investigate the relationship between occlusal contacts, overbite, transverse expansion, and the buccolingual inclination of the teeth with reference to the predicted treatment outcomes and achieved outcomes related to the use of the Invisalign® appliance in mild-to-moderate Class I malocclusions. MATERIAL AND METHODS: The occlusal contacts, overbite, the buccolingual inclination and transverse expansion of the maxillary arch of adult patients satisfying inclusion and exclusion criteria were measured at the initial (pre-treatment), predicted, and achieved treatment stages using metrology software. Pearson correlation coefficients and regression equations were calculated to determine the association between the initial, predicted and achieved changes in occlusal contact against the other variables. RESULTS: Thirty-three patients, who commenced treatment between 2013 and 2018 and satisfied inclusion/exclusion criteria were evaluated. An overall loss of posterior contact was recorded and highlighted by a significantly greater loss of contact from the maxillary buccal occlusal surfaces compared to the palatal occlusal surfaces. The mean [SD] achieved overbite outcome (2.94mm [1.17]) was greater than the predicted (1.74mm [0.87), P<0.001). The buccolingual inclination was significantly increased for the lateral incisors and first and second molars despite a predicted decrease (P≤0.007). Achieved transverse expansion showed significant variation from the predicted. The loss of posterior occlusal contact was correlated with the buccolingual inclination (r=0.70) and transverse expansion (r=0.74) of the posterior teeth. CONCLUSIONS: In mild-to-moderate Class I malocclusions, treatment using the Invisalign® appliance resulted in an overall loss of posterior contact. The loss of occlusal contact was correlated with deficiencies in achieved buccolingual inclination and transverse expansion of the posterior teeth. Planned bodily expansion was ineffective as most expansion occurred due to unplanned buccal tipping.