AIM: This in vitro study investigates the limit of expansion forces and torque wrench forces developed by five skeletal bone expander designs (MICRO 2/4 expanders™) for clinical application. MATERIAL AND METHODS: A total...AIM: This in vitro study investigates the limit of expansion forces and torque wrench forces developed by five skeletal bone expander designs (MICRO 2/4 expanders™) for clinical application. MATERIAL AND METHODS: A total of 30 skeletal expanders were placed in artificial bone blocks and mechanically tested, simulating maxillary expansion. Differences in jackscrew (Dentaurum™ [D], Superscrew™ [S] and Powerscrew™ [P]), number of orthodontic mini-implants (OMIs; two or four) and their placement inclinations (parallel 0° or 10° inclination) form five designs (D4/10°, S4/0°, S4/10°, P4/10° and P2/10°). Expansion forces and torque wrench values were registered, and radiographs were made initially and after 4 mm of expansion. Stress-strain curves were obtained after successive activations and the statistical analysis was performed as appropriate. RESULTS: Plastic deformations in the OMIs and jackscrew occurred around the activation numbers 11-13, with torque wrench values in the range of 500-700 cN. The maximum expansion forces in expanders with four OMIs varied from 93.0 (D4/10°) to 166.6 N (P4/10°) whereas two OMI expanders (P2/10°) registered forces of 79.4 N. Radiographs revealed during loads bending forces (S4/00°, S4/10°) with jackscrew and OMIs deformation in a convex shape, and shear forces (P4/10°, P2/10°) demonstrated only OMIs deformation in a concave shape, providing 15% more expansive force. The jackscrew D4/10° did not have any deformation, but its wire key did not allow reliable activations from activation number 10 and compared to S4/10° and P4/10°, these expanders provided greater expansion forces ( = 0.000 and = 0.032, respectively). CONCLUSION: The different results obtained in stability and expansion forces indicate that if the activations are carried out under extreme conditions, they may have clinical importance with deformations and non-working expansion mechanics. Jackscrew designs play an important role in expansive forces and expander stability. Torque wrench values can be used clinically as a tool to asses the expansion forces and to avoid deformations.
An increasing number of clinicians have been utilising orthodontic mini-screws as temporary anchorage devices (TAD) in their practices, but variable successful rates have been reported. Here, we introduce a practical app...An increasing number of clinicians have been utilising orthodontic mini-screws as temporary anchorage devices (TAD) in their practices, but variable successful rates have been reported. Here, we introduce a practical approach to inserting mini-screws successfully. Using computer-aided design (CAD) and computer-aided manufacturing (CAM) technology, the surgical guide for pre-drilling was designed and fabricated and mini-screws were placed following pre-drilling holes in two cases. Two Ø2.0 × 10.0-mm mini-screws were inserted into the prepared holes in the mandibular buccal shelf (MBS) on both sides with a hand driver to distalise the lower molars for Class III correction. The treatment was done successfully, after 12 months of treatment in one case. Two Ø1.6 × 8.0-mm mini-screws were inserted into the prepared holes in the mandibular alveolar process in another case with congenital absence of lower right second premolar. One mini-screw was in the buccal alveolar process between the mandibular right canine and first premolar and the other in the lingual alveolar process between the mandibular right first premolar and second primary molar. The lower right molars would be protracted to close the space left after the extraction of the primary molar using the two mini-screws. The case was still in treatment.
OBJECTIVES: The aim of this study was to determine the quality, reliability and usability of information on the Internet regarding hypodontia. METHOD: A survey of patients with hypodontia revealed seven key search terms...OBJECTIVES: The aim of this study was to determine the quality, reliability and usability of information on the Internet regarding hypodontia. METHOD: A survey of patients with hypodontia revealed seven key search terms favoured by patients: Hypodontia; Congenitally missing teeth; Missing teeth; Gaps in teeth; Cure of missing teeth; Information on missing teeth; and Treatment of missing teeth. These were entered into four search engines: Google; Ask; Wikipedia; and NHS Choices. Relevant websites were assessed for their overall demographics, author type, country of origin and rank within the search engine. They were then analysed using five validated assessment tools. Intra-examiner reliability was assessed, and statistical analysis of the data was undertaken. RESULTS: Good intra-examiner reliability was observed. A total of 48 websites were included for analysis from an initial 1718. There was no relationship between the ranking of a website on a search engine and the quality of information it contained. When medical search terminology was used, it resulted in websites of better quality than layperson search terms. Most websites were produced by general dental or specialist dental practices but the quality of these was poorer than those developed by private companies and medical organisations. The country of origin was primarily the USA and UK; however, this had no relationship to website quality. Overall, the majority of websites scored poorly for the validated tools and none scored well across multiple tools. A statistical analysis showed a positive relationship between the LIDA and DISCERN instruments but no other correlation between other validated tools was found. CONCLUSION: The quality and reliability of information on the Internet regarding hypodontia is generally poor. There is a need for a reliable online hypodontia resource that can be recommended for patient use.
OBJECTIVE: To assess the surface roughness of in-house 3D-printed orthodontic aligners compared with Invisalign appliances, both retrieved as well as in the 'as-received' control status. DESIGN: An in vitro study followi...OBJECTIVE: To assess the surface roughness of in-house 3D-printed orthodontic aligners compared with Invisalign appliances, both retrieved as well as in the 'as-received' control status. DESIGN: An in vitro study following intra-oral material aging. SETTING AND PARTICIPANTS: Twelve clinically used Invisalign appliances and the same number of 3D-printed aligners, without involvement of attachments, were obtained from a respective number of patients. A similar number of 'as-received' aligners, of each material, were used as control (CON) groups. METHOD: Four groups of materials were examined: A = Invisalign CON; B = Invisalign used; C = 3D-printed CON; and D = 3D-printed used. Optical profilometry was employed to examine the following surface roughness parameters: amplitude parameters Sa, Sq and Sz and functional parameters Sc and Sv. Descriptive statistics and quantile regression modeling were conducted, and the level of statistical significance was set at α = 0.05. RESULTS: Intra-oral exposure of 3D-printed aligners was significantly associated with increase in all tested parameters ( < 0.001 at all occasions). Significant differences were detected in the retrieved 3D-printed aligners compared with Invisalign retrieved, with the exception of Sz. The respective effect sizes (median differences) were as follows: Sa: 169 nm, 95% confidence interval [CI] = 89-248, < 0.001; Sq: 315 nm, 95% CI = 152-477, < 0.001; Sc: 233 nm/nm, 95% CI = 131-335, < 0.001; and Sv: 43 nm/nm, 95% CI = 17-68, = 0.002. CONCLUSION: Within the limitations of this study, we concluded that surface roughness differences existed between 3D-printed aligners and Invisalign in the retrieved status, as well as between the control and retrieved 3D-printed groups.
OBJECTIVE: To compare the effect of chewing sugar-free gum towards alleviating self-reported orthodontic treatment (OT) pain compared with conventional analgesic drugs (CADs). SEARCH SOURCES: An unrestricted search of in...OBJECTIVE: To compare the effect of chewing sugar-free gum towards alleviating self-reported orthodontic treatment (OT) pain compared with conventional analgesic drugs (CADs). SEARCH SOURCES: An unrestricted search of indexed databases and manual searching was performed up to September 2021. DATA SELECTION: Randomised controlled trials (RCTs) comparing the impact of chewing gum and CADs on relieving self-reported orthodontic pain were included. DATA EXTRACTION: Data screening, extraction and risk of bias (RoB) assessment were performed by two authors. Meta-analyses were performed using a random-effects model. The quality of available evidence was assessed using the Grades of Recommendation, Assessment, Development and Evaluation approach. RESULTS: Nine RCTs were included. Eight RCTs used the Visual Analogue Scale for self-reported pain assessment, while one RCT used the Numeric Rating Scale. Five RCTs had a high RoB and four RCTs had a moderate RoB. Power analysis for sample size estimation was performed in six RCTs. Separate meta-analyses were performed by pooling quantitative data from five RCTs that compared self-reported orthodontic pain between chewing gum and ibuprofen groups for the following timepoints: baseline; immediately; 2 hours; 6 hours; bedtime; 24 hours; 2 days; 3 days; 5 days; and 7 days after the placement of orthodontic appliances. None of the timepoints individually indicated a difference in self-reported pain scores between chewing sugar-free gum and ibuprofen groups. The overall level of evidence was very low. CONCLUSION: Chewing sugar-free gum is a potentially useful alternative to CADs towards pain alleviation during fixed OT.
This case report describes the camouflage treatment of an adult patient with hyperdivergent facial pattern presenting with severe Class II skeletal malocclusion, through the use of a hybrid clear aligner approach, that r...This case report describes the camouflage treatment of an adult patient with hyperdivergent facial pattern presenting with severe Class II skeletal malocclusion, through the use of a hybrid clear aligner approach, that relies on both a partial lingual fixed appliance and the continuous use of Class II elastics throughout therapy. After 11 months of treatment, the goals had been achieved, highlighting that the correct diagnostic framework, proper patient selection and careful digital planning of a compromise treatment can provide satisfactory aesthetic and functional outcomes.
Adults presenting with transverse maxillomandibular discrepancies in Class III skeletal patterns, asymmetries and anterior open bite can be challenging to treatment plan and manage. Therefore, they often necessitate a mu...Adults presenting with transverse maxillomandibular discrepancies in Class III skeletal patterns, asymmetries and anterior open bite can be challenging to treatment plan and manage. Therefore, they often necessitate a multidisciplinary approach, with surgical input from the oral and maxillofacial team. It can be difficult to assess how much the maxilla needs to be expanded after surgery in these patients, as the upper and lower teeth cannot be brought into occlusion. We aim to discuss the use of a device we have come to call the 'Powerbite', which is used intra-orally to assess the expansion of the maxilla after surgically assisted rapid palatal expansion (SARPE) and establish when expansion is sufficient to accommodate the mandibular arch. This device is not novel, last described in 1986 in the .
INTRODUCTION: Interproximal enamel reduction is a part of the orthodontic treatment as a method of space generation in addition to other vast indications. Some studies found that different techniques might impose changes...INTRODUCTION: Interproximal enamel reduction is a part of the orthodontic treatment as a method of space generation in addition to other vast indications. Some studies found that different techniques might impose changes to the enamel surface that alter its topography, which in turn might influence its integrity and susceptibility to caries. Polishing, however, after this procedure is thought to be helpful to reduce these adverse effects. AIM: To evaluate the nano-topography of the enamel surfaces after interproximal reduction (IPR) and determine its influence on enamel surface roughness and examine the need for polishing to minimise these influences, when combined with topical fluoride application. METHODS: A total of 60 proximal surfaces of 40 extracted maxillary premolars (10 premolars left unprepared as the control group) were reduced with different stripping instruments (discs, burs and manual strip system). The surface roughness of enamel was analysed with an atomic force microscope to determine the results quantitatively as well as qualitatively on the nanoscopic scale. One of each proximal surface was followed by polishing and fluoride varnish after the reduction. RESULTS: The results showed that surface roughness was increased in all groups without polishing. The greatest mean roughness was recorded for the disc group (212 ±125.7), followed by the bur group (172 ±93.1) and manual strips (153.8±106.7). The difference between the groups, however, was not significant for both mean roughness ( = 0.656) and height ( = 0.737). The parameters were decreased after polishing in all groups but the difference between methods was not significant for both parameters ( = 0.946 and = 0.849); however, the mean height was reduced to nearly half the reading in the bur and manual strip method. The disc group only showed a statistically significant decrease in surface roughness with polishing ( < 0.05). All other results were not significant. CONCLUSION: All methods of interproximal reduction do not influence enamel surface nanotopography significantly with and without polishing. Polishing resulted in significant reduction of surface roughness only in the disc group.
The Twin Block appliance (TBA) has evolved over the decades to remain a very effective treatment for growing Class II patients. This article introduces how two new versions of the TBA may be produced through an entirely...The Twin Block appliance (TBA) has evolved over the decades to remain a very effective treatment for growing Class II patients. This article introduces how two new versions of the TBA may be produced through an entirely digital workflow, from intra-oral scanning to thermoplastic appliance fabrication, using a novel computer-aided design process.
OBJECTIVE: To explore university students' experience of retention and identify potential barriers and facilitators to long-term adherence. DESIGN: Cross-sectional qualitative study using virtual focus groups. SETTING: U...OBJECTIVE: To explore university students' experience of retention and identify potential barriers and facilitators to long-term adherence. DESIGN: Cross-sectional qualitative study using virtual focus groups. SETTING: University of Leeds. PARTICIPANTS: Dental and non-dental students from the University of Leeds, who had previously undergone orthodontic treatment and had received removable retainers. METHODS: Students were invited to participate via email. Virtual focus groups were undertaken using Microsoft Teams. A topic guide was used to explore the experience of orthodontic retention including factors that influence long-term retainer wear. Focus groups were recorded and analysed using an inductive thematic approach. RESULTS: In total, 23 students participated in four focus groups, including 13 dental students. The period since the end of orthodontic treatment varied from 9 months to 10 years. Of the 23 participants, 8 (35%) were no longer wearing their retainers. Four themes were identified: (1) experience of orthodontic treatment including knowledge of relapse; (2) experience of retainer wear, including motivators and barriers; (3) role of others; and (4) increasing adherence. Key factors influencing use of retainers were the importance placed on maintaining treatment outcomes, awareness of unwanted tooth movement and understanding of the role of the retainer, access to replacement retainers, and ongoing support to encourage retainer wear. Greater knowledge and dental awareness reported by dental students did not necessarily increase adherence. CONCLUSION: Adherence to removable retainer wear is an important aspect of orthodontic treatment but it is recognised that long-term retainer wear is highly variable. The understanding of relapse and retention is variable. Challenges in gaining access to replacement retainers are a common cause of cessation of retainer wear. Dental professionals are perceived to be important in encouraging and supporting retainer wear and individuals reported they would like more follow-up.
OBJECTIVE: To investigate long-term changes and possible seasonal variations in Google search volumes related to Invisalign in developed and developing countries. DESIGN: Cross-sectional, Google search-based study. METHO...OBJECTIVE: To investigate long-term changes and possible seasonal variations in Google search volumes related to Invisalign in developed and developing countries. DESIGN: Cross-sectional, Google search-based study. METHODS: Google Trends (GT) was accessed to retrieve the Relative Search Volume (RSV) of Google queries related to the search term 'Invisalign' in 10 countries selected on the basis of population size, Internet usage and socioeconomic criteria between 1 January 2004 and 30 June 2021. The countries examined were the following: Australia, Brazil, Italy, Mexico, Philippines, Saudi Arabia, Spain, Thailand, UK and USA. By applying the time series decomposition method, the trend component and the seasonal variation were identified. RESULTS: Overall, RSVs regarding Invisalign have increased significantly in all countries with the developed countries outperforming developing countries throughout most of the observation period. There was no meaningful pattern when the trends were compared either on a monthly or quarterly basis. Similar peaks and valleys were found in Australia - Brazil, UK - USA, Italy - Spain and Saudi Arabia - Philippines - Thailand. CONCLUSIONS: Public interest in online information for Invisalign has grown significantly over the years across countries of diverse socioeconomic and cultural backgrounds while seasonal patterns were observed in the related Google searches. Seasonal fluctuations seemed to follow the academic calendar. The study results may have direct implications on practice management and professional development.
OBJECTIVE: To assess the content accuracy of orthodontic treatment information in patient-focused apps. DESIGN: A cross-sectional review study. SETTING: Orthodontic apps available on the UK Android and Apple App Stores....OBJECTIVE: To assess the content accuracy of orthodontic treatment information in patient-focused apps. DESIGN: A cross-sectional review study. SETTING: Orthodontic apps available on the UK Android and Apple App Stores. METHODS: Apps identified in a previous research study and those identified via a questionnaire of specialist orthodontists were assessed for accuracy of content utilising an evidence-based checklist. The checklist covered five main orthodontically relevant themes and 32 codes with respective items. RESULTS: The accuracy of information content for 16 patient-focused apps was assessed. Eight apps provided information related to orthodontic treatment and handling emergencies. Five apps were reminder apps and a small number (n = 3) contained games and timers for toothbrushing and aligners. With regard to the accuracy of information content, only two apps contained information across all five themes of the evidence-based checklist. Only one app received a score of 'fair - excellent' under the oral hygiene theme; interestingly, this app was the most commonly used patient-focused app. Eight apps containing orthodontic treatment information scored poorly as they had inaccurate information on handling emergency situations. None of the apps were deemed excellent with regard to accuracy of information content. CONCLUSION: The orthodontic mobile apps assessed in this study mostly contained information of poor accuracy. Therefore, there is a need for high-quality apps with credible information supported by evidence to be developed.
Among non-gender conforming populations, there is a subgroup of individuals who experience significant distress associated with their gender incongruity, commonly referred to as gender dysphoria (GD). In the UK, there is...Among non-gender conforming populations, there is a subgroup of individuals who experience significant distress associated with their gender incongruity, commonly referred to as gender dysphoria (GD). In the UK, there is a recognised pathway for individuals experiencing GD. This has traditionally been initiated by a referral to the Gender Identity Development Service (GIDS) for children and adolescents or to a Gender Identity Clinic (GIC) for adults. This pathway can potentially involve several specialties and treatment modalities, including the prescription of various hormones. It is important for orthodontists to have an understanding of this field, as well as the potential treatment modalities, so that they can support this often marginalised patient group. Inherent differences between male and female facial features may also lead patients with GD to present to orthodontists, wishing to change their facial appearance. This article highlights the current national pathway for GD and the orthodontic considerations for these individuals.
OBJECTIVES: To assess technical factors and audience preferences before attending orthodontic online learning activity, the demand for which increased dramatically in the era of the COVID-19 pandemic. DESIGN: Cross-secti...OBJECTIVES: To assess technical factors and audience preferences before attending orthodontic online learning activity, the demand for which increased dramatically in the era of the COVID-19 pandemic. DESIGN: Cross-sectional study. SETTING: Online survey. PARTICIPANTS: Global orthodontic residents and specialists. METHODS: A validated and anonymous survey comprising 17 online questions was sent to 3000 individuals. The data were collected three months later. Descriptive statistics and non-parametric tests were applied. RESULTS: The participants' response rate was 19.9%, with almost equal gender participation. Most of the responders were based in Asia (51.4%). Almost half of the participants were aged 25-35 years with less than 5 years of clinical experience. Regardless of the age, gender or global distribution, of respondents opted to share limited personal information with the host. One-third of the respondents preferred receiving webinar reminders via email, ideally a day and/or one hour before the webinar, especially being exportable to their calendars. Age played a major role in shaping this trend, as young participants favoured the one hour (1-h) pre-webinar reminder more than other age groups (=0.02). Receiving information about the speaker, learning outcomes and pre-webinar reading material (WRM) were preferable, particularly among young participants in comparison with the older age groups (<0.05). Male participants from Asia and Africa preferred to attend online lectures during the mid-evening on weekends compared with women who were in favour of early evening sessions (<0.05). CONCLUSION: It must be borne in mind during the interpretation of the results that the data were collected during the COVID-19 pandemic. It is important to take into consideration the gender, age, cultural background and level of experience while setting up virtual orthodontic learning sessions. Organisers need to tailor their events to meet the needs of the attendees.
OBJECTIVE: To develop a tool to facilitate simple, easy and rapid assessment of the level of difficulty in disimpaction of an impacted canine using cone-beam computed tomography (CBCT). DESIGN: A cross-sectional study. M...OBJECTIVE: To develop a tool to facilitate simple, easy and rapid assessment of the level of difficulty in disimpaction of an impacted canine using cone-beam computed tomography (CBCT). DESIGN: A cross-sectional study. METHODS: A panel of four experienced orthodontists formulated a questionnaire capable of portraying the limits of a three-dimensional (3D) area around impacted maxillary canines on CBCT images, which would determine the disimpaction difficulty level. In total, 14 experienced orthodontists graded each item in the questionnaire and assigned scores in the range of 0-5. Average scores obtained outlined the limits of a 3D area, within which an impaction was deemed favourable. This area was termed 'Easy box'. The disimpaction difficulty level of 170 impacted maxillary canines was then assessed using 'Easy box' and the existing tool KPG index for convergent validation. RESULTS: Perfect inter-examiner agreement was obtained as evidenced by Fleiss kappa value of 0.984 for the tool 'Easy box' and 0.948 for the KPG index. There was also perfect agreement between the two methods of assessment (Cohen weighted kappa, k>0.86). The average time taken for assessment using 'Easy box' was 3.3 min compared to 8.8 min for the KPG index. CONCLUSION: 'Easy box' proves to be a simple, accurate and rapid assessment tool for the prognostic evaluation of impacted canines, using CBCT images. Impacted maxillary canines with cusp tips that lie beyond the limits of the 3D 'Easy box' area with a beta angle greater than 45°, were rated to be more difficult to align.
INTRODUCTION: The aim of these two case-reports is to illustrate and compare the therapeutic effects of Class II elastics in combination with F22 aligners in an adult and an adolescent patient, respectively. CASE PRESENT...INTRODUCTION: The aim of these two case-reports is to illustrate and compare the therapeutic effects of Class II elastics in combination with F22 aligners in an adult and an adolescent patient, respectively. CASE PRESENTATION: Two patients with a mild skeletal Class II malocclusion, associated with mild-to-moderate crowding, presented for orthodontic treatment. The first patient was 12 years old, while the second was 40 years old. In both cases, the goal was to obtain bilateral molar and canine Class I with ideal overjet and overbite, and Class II skeletal relationship improvement in the young patient as well. Both treatments were approached without extractions and using clear aligners (CAs) in combination with Class II elastics, giving the patient the opportunity to take advantage of a therapy that is both comfortable and aesthetic. DISCUSSION: Final records of both cases demonstrate how appropriate analysis and diagnosis enable CAs in conjunction with Class II elastics to be used with considerable efficiency and efficacy for Class II treatment. In the first case, the key to success was exploiting residual jaw growth, while in the second case it was careful orthodontic digital planning. CONCLUSION: In the presence of good patient compliance, CAs associated with Class II elastics provide satisfactory occlusal outcomes if biomechanics and digital set-up are carefully evaluated and executed and if diagnosis is appropriate.