Volumen 37 (2021): Edición 2 (July 2021)

To systematically review the effectiveness of 5% sodium fluoride varnish (FV) in the treatment of orthodontically-induced white spot lesions (WSLs).

A literature search of three independent databases (Medline, Cochrane Library and Web of Science) was performed from inception to November 2020. This systematic review included randomised/quasi-randomised clinical trials (RCTs) that used FV for patients who had at least one WSL as a result of fixed orthodontic treatment. Exclusion criteria were split-mouth study designs or studies that failed to report WSLs as the outcome variable or studies with less than 3 months follow-up. An Inverse-Variance fixed-effect method was performed for continuous variables. Changes in the mean difference (MD) for the DIAGNOdent (DD) scores following FV application were calculated at the 95% confidence interval (CI).

Three of the four included studies showed significant improvement in the remineralisation of WSL after treatment with FV in comparison to control subjects. Three studies were conducted on patients after fixed orthodontic treatment and one study was conducted during treatment. The studies included a total of 284 participants with the majority in the age range of 10 to 25 years. The distribution of the participants was approximately equal in the FV and control group. When compared with the control group, there was a statistically significant reduction in the mean DD readings for the FV group at the 3-month (MD = -3.43; 95% CI: -4.72 to -2.15; p < 0.001) and at the 6-month (MD = -4.47; 95% CI: -4.72 to -2.15; p < 0.001) follow-up visit.

Although few studies have shown the effectiveness of FV application in the treatment of orthodontically-induced WSLs, the limited number of robust clinical trials, makes it difficult to draw a definitive conclusion.

Using a thermal camera, the aim of the study was to determine pulp chamber temperature changes during orthodontic bonding produced as a result of variations in curing light sources, different curing distances and bracket types.

One hundred sixty maxillary premolar teeth were sectioned into two halves and embedded into acrylic moulds. Four curing light sources were used which further divided the overall sample into Halogen, light emitting diode (LED), powered LED, and high-power LED groups. Additional subgroups were created according to the applied curing distances (5 mm, 10 mm) and different bracket types (metallic or ceramic). A standardised bonding procedure was performed and pulp chamber temperature changes were evaluated using a thermal camera. Statistical analysis was performed using a three-way ANOVA.

The Halogen light curing group revealed a significantly higher temperature rise in the pulp chamber compared to the other groups. A shorter curing distance produced increases in pulpal temperature. There was no significant effect as a result of the bracket type.

None of the curing light sources exceeded the critical value for pulp chamber temperature rise. The primary desirable outcome was the lowest temperature increase noted with the high-power LED unit. The secondary outcome related to the different brackets revealed no difference relative to pulp chamber temperature change. From a clinical perspective, high-power LED units could be safely used.

Interproximal reduction (IPR) is a treatment option for orthodontic space gain. The attainment of prescribed objectives in aligner treatment may require IPR that is accurately performed both qualitatively and quantitatively.

This study assesses the in vivo accuracy of IPR carried out in 10 orthodontic practices as a method of orthodontic space creation.

A comparison of proposed and achieved amounts of IPR completed (accuracy), the accuracy of IPR within and between upper and lower dental arches, and the accuracy of IPR within and between posterior and anterior arch segments were performed using 3-dimensional digital study models gained via Align’s^® ClinCheck.

The findings indicated that IPR was routinely underperformed by all practices studied. On average, the amount of IPR achieved represented only 44.0% of the total prescribed per tooth in the sample assessed, with a mean discrepancy of 0.16 mm per tooth. There were statistically significant differences only between the overall anterior and posterior groups (p < 0.01) and between maxillary anterior and maxillary posterior groups (p < 0.01); however, these were not clinically significant. Significant differences in IPR performance were noted between different orthodontic practices.

This study demonstrates that the clinical performance of IPR in 10 orthodontic practices consistently fails to achieve the prescribed amount often by large variations. The effect of this under-performance on clinical outcomes remains to be quantified.

To evaluate the perception of smile aesthetics and midline deviation considered by orthodontists (ORT), dentists (DT), patient’s-relatives (PR), and laypersons (LP) using an eye-tracking device and survey.

The study invited the participation of 42 orthodontists, 51 dentists, 50 patient-relatives, and 52 laypersons. A posed smile photograph of a female was chosen as a base image. The dental midline (DML) was digitally moved 1 mm (DML1R, DML1L), 2 mm (DML2R, DML2L), 3 mm (DML3R, DML3L), and 4 mm (DML4R, DML4L) on the base image’s right (DMLR) and left (DMLL) segments. Eight modified images were subsequently obtained. The base, modified, and repeated images were randomly arranged and uploaded into the Tobii Pro Lab software program for assessment by the participants. An eye-tracking dataset included first fixation duration (FFD), total fixation duration (TFD), and visit counts (VC). The participants also evaluated the photographs on the survey forms via a Visual Analogue Scale (VAS) and a Likert scale. The intra-group relations and inter-group correlations were evaluated statistically.

The TFD for the DML2R photograph was found to be statistically significant between the assessment groups (p = 0.026). While the longest fixation time (0.93 sec) belonged to the orthodontists, it was observed that the patient relatives had the shortest fixation time (0.51 sec). The VAS score for the DML2R image was found to be highest in laypersons (p < 0.001). In general, the survey scores of the patient relatives and laypersons were higher.

The fixation time between the participant groups increased when there was a 2 mm deviation. A 2 mm shift in the DML was noticed by all participant groups and was considered unaesthetic.

The aim of this study was to evaluate the use of functional appliances by the currently practising orthodontists in Malaysia. The objectives were to identify the different types of functional appliances used by Malaysian orthodontists and to investigate the variation in treatment protocols when attempting growth modification.

An online questionnaire consisting of 24 open-ended and multiple-choice questions was emailed to members of the Malaysian Association of Orthodontists (MAO) (n = 183). The survey was based on a previous study conducted by members of the British Orthodontic Society and was modified to suit the Malaysian population. The data were analysed using SPSS to generate frequency tables and descriptive statistics.

Seventy-two responses were received from current Malaysian orthodontists. Of the respondents, 71% practised in a government setting and 29% were in private practice. The Clark Twin Block was the most frequently used functional appliance by 90% of Malaysian orthodontists. Many of the respondents (57%) prescribed full-time wear of removable functional appliances for 6–9 months (except during mealtimes) (51%). Following active removable functional appliance therapy, 91% prescribed a period of retention which involved a reduction in the duration of wear. The retention phase extended for 2 to 3 months (41%) or for 4 to 6 months (39%) for the majority of the respondents.

The Clark Twin Block is the most frequently-used functional appliance for the management of a Class II malocclusion by orthodontists currently practising in Malaysia.

This article presents the nonsurgical orthodontic treatment of a skeletal Class III malocclusion of an adult patient.

Because the patient refused an orthognathic surgical procedure, the mandibular first premolars were extracted and orthodontic camouflage using miniscrew anchorage was used to correct dental asymmetries and the occlusal relationship.

The treatment strategy was successful and provided an acceptable aesthetic functional occlusion.

When appropriately indicated, the orthodontic camouflage of a class III malocclusion can avoid orthognathic surgery and, through the use of mini-implants as skeletal anchorage, enhance the results.

The importance of assessing patients for paediatric obstructive sleep apnoea (OSA) cannot be more highly stressed and orthodontists may play an essential role in risk screening. The Paediatric Sleep Questionnaire (PSQ) is a validated tool to identify whether a child is at risk for paediatric OSA.

The likelihood of paediatric OSA in school-aged children residing in Far North Queensland (FNQ) will be assessed using the PSQ.

Parents of children aged between 4 and 18 years were invited to participate through schools and social media messaging to complete an online PSQ questionnaire to assess their OSA risk and demographics.

The final sample consisted of 404 school-aged children of whom 62.5% were found to be at a high-risk for paediatric OSA. The high risk was significantly associated with males and those of overweight/obese BMI status (p < 0.001). Race and age were not significant associations (p > 0.05).

Within the contributing sample of school-aged children in FNQ, a significant number were found to be at high-risk of paediatric OSA. Males and overweight/obese children were measured risk factors.

The aim of the study was to evaluate the cephalometric effects of the elastodontic appliance (EA) in the management of patients presenting with a skeletal Class II/1 malocclusion.

Twenty Class II patients treated using the EA (Group EA) were compared with 20 Class II untreated children (Group C). Cephalograms were compared at the start (T0) and after 24 months (T1) after which time, skeletal, dental, and aesthetic variables were evaluated. A statistical evaluation was conducted by applying an unpaired t-test for normally distributed variables.

From T0 to T1, the EA group showed a significant increase in lower facial height (LFH), in mandibular length (Co-Gn), in the upper incisor and cranial plane angle (1 + SN) and in the distance between a true vertical line (TVL)-soft tissue B (B’) and TVL-soft tissue Pogonion (Pog’) points. From T0 to T1, group C showed a significant decrease in SN-occlusal plane (PO) (p < 0.01), of SN-mandibular plane (Go-Me) (p < 0.01) and of total gonial (N-Go-Me) angles (p < 0.05); a significant reduction of the distance between TVL-upper incisor (1+), TVL-lower lip (Li), and TVL-Pog’ was shown. No statistical differences were observed between the groups in dental and aesthetic outcomes, except for a skeletal increase in LFH (p < 0.05) and in Co-Gn length (p < 0.05), which was statistically significant in the EA group.

In Class II growing patients, the EA induces minor skeletal effects, compared to untreated control patients.

The aim of this prospective study was to assess the amount of interlabial gap (ILG) and freeway space (FWS) at rest position (RP) according to gender, age, and skeletal pattern, and to evaluate the cephalometric measurements at maximum intercuspal position (MIP) and at RP to define the cephalometric changes from MIP to RP related to the amount of ILG and FWS.

Lateral cephalograms and photographs of selected subjects (47 females, 57 males) were obtained at MIP and RP. Cephalometric measurements at MIP and RP and their differences were measured and compared.

ILG (P > 0.05) and FWS (P < 0.01) were greater in males than in females. ILG (P < 0.05) and FWS (P > 0.05) were greater in adolescents than in adults. ILG and FWS were not significantly related with the vertical skeletal pattern (FHR, facial height ratio). ILG was the greatest in Class II cases but without significance. FWS was significantly greater in Class III than in Class I and Class II cases (P < 0.05). At MIP, the ILG at RP increased as overjet (P < 0.05) and upper lip to the aesthetic line (P < 0.01) increased. At RP, the ILG increased as upper incisor exposure and the lips to the aesthetic line increased (P < 0.001), and FWS decreased as overbite decreased (P < 0.001). From MIP to RP, lip length showed the greatest decrease (P < 0.001) in the large ILG group. Additionally, Bjork sum (the sum of the saddle, articular, and gonial angles), mandibular plane angle, anterior facial height, and ANB (P < 0.001) showed the greatest increase, while OB (P < 0.001) showed the greatest decrease in the large FWS group. The lip competent group showed the largest frequency distribution in the small ILG and FWS groups, while smile line frequency distribution showed no relationship with the level of ILG and FWS.

Taking cephalometric measurements at RP would be helpful to evaluate the ILG and FWS more accurately, and to provide a more accurate diagnosis and treatment plan.

Space maintainers are used to preserve created space caused by the premature loss of primary teeth but they may also upset the oral environment and play a role in caries formation. The current research aimed to assess the impact of removable and fixed space maintainers on salivary pH, flow rate, and the oral microflora.

Thirty-eight patients aged between 4 and 10 years, each of whom required a fixed (n = 19) or removable space maintainer (n = 19), were enrolled in this research. The salivary pH, saliva flow rate, salivary Streptococcus mutans, and Lactobacillus counts were measured immediately prior to the placement of the space maintainers (baseline-T0) and during the follow-up period, at the 1st (T1), 3rd (T3), and 6th (T6) month. The Wilcoxon, Mann–Whitney U test and Friedman tests were applied for statistical analyses.

Streptococcus mutans and Lactobacillus counts were significantly higher at the 6th month time period in comparison with the baseline scores for both groups (P < 0.001). The salivary pH and flow rates did not change significantly at any measurement period (P > 0.05).

Space maintainers can favour caries formation by changing the oral microflora. It is advisable to warn patients and their parents of the risks and provide motivation to perform meticulous oral hygiene.

The aim of the present study was to evaluate the quality of information uploaded onto the Internet regarding accelerated orthodontics.

The selected search terms ‘accelerated orthodontics’, ‘rapid orthodontics’, ‘speed orthodontics’, ‘rapid braces’, and ‘speed braces’ were searched by three commonly used search engines (Google, Yahoo, and Bing), and the URLs of the top 50 websites were recorded. The websites were evaluated using DISCERN, HONcode, and the Journal of the American Medical Association (JAMA) benchmark instruments. The readability of the websites was evaluated by the Flesch Reading Ease Score (FRES) and the Flesch-Kincaid Grade Level (FKGL).

The total mean DISCERN score (section 1 + section 2) for all websites was 29.50/75 (range: 15–68). The average FRES of all websites was 52.99 ± 31.91. Also, the average FKGL score of all websites was 10.73 ± 2.03. Professional health organisation websites had significantly higher DISCERN scores than other websites (p < 0.001). Only three websites had the HONcode seal. Professional organisation and private dental practice websites showed better compliance with JAMA benchmarks. There was no statistically significant difference related to FRES and FKGL scores between groups (p > 0.05).

Information regarding accelerated orthodontics found on the Internet is insufficient. It is recommended that orthodontic societies and orthodontists increase the quality of the websites which describe accelerated orthodontics.

The purpose of this study was to assess the current literature on the effectiveness of rapid palatal expansion (RPE) in assisting the spontaneous eruption of impacted maxillary canines.

Four electronic databases were searched (Pubmed, Scopus, Web of Science, Embase) by applying appropriate Medical Subject Headings (MeSH). Two authors independently and systematically reviewed the literature. Randomised controlled trials (RCTs) and prospective controlled clinical trials (pCCTs) were identified and selected. The Cochrane Collaboration’s risk of bias tool and the risk of bias in non-randomised studies of interventions (ROBINS-I) were used to assess the quality of the obtained articles. Spontaneous canine eruption was used as a primary outcome.

Three RCTs and two pCCTs met the inclusion criteria. One study was assessed at a high risk of bias in the RCT group, while the remainder were at an unclear risk of bias. Both pCCTs were classified as a moderate risk of bias based on the ROBINS-I tool. The success rate of canine eruption following RPE, with or without additional treatment, ranged from 65.7 to 85.7%, which was statistically significantly different from the control group.

RPE appears to improve the position of displaced maxillary canines and increase the likelihood of spontaneous eruption. However, there is a shortage of high-quality evidence to conclude that RPE can be an effective treatment option for impacted maxillary canines.

Proposed skeletal changes achieved by functional appliances (FA) with reference to stable structures (structural method) have received relatively little attention compared to conventional cephalometric measurements (conventional method). Using the two methods, the aims of this study were to (1) determine the skeletal changes as a result of FA treatment; and (2) identify the skeletal changes associated with upper-airway volume and minimum cross-sectional area (MCA).

Pre- and post-treatment CBCT scans were selected from 73 FA treated children (37 girls and 36 boys; mean age 12.0 years) and 73 children as a control group (matched for chronological age, skeletal age, gender, and mandibular inclination) who received orthodontic treatment using only fixed appliances (no FA). Skeletal, upper-airway volume, and MCA changes were analysed by applying both structural and conventional methods.

The FA group had significant skeletal effects compared with the control group (both methods; p = 0.04 – p < 0.001). The horizontal displacement of pogonion (both methods) and the hyoid bone, together with a forward mandibular rotation (structural method), had positive effects on upper-airway volume and MCA (p < 0.05).

The horizontal changes in pogonion (both methods) and the hyoid bone, as well as a forward mandibular rotation (structural method), have a strong association with changes in the upper airway. The conventional method underestimates FA treatment effects. These results may influence the management of growing class II patients with compromised upper airways.

To investigate the cephalometric outcome and post-treatment changes following the orthodontic treatment involving the extraction of maxillary first molars in patients presenting with a Class II division 1 malocclusion.

A retrospective longitudinal study was conducted involving 83 patients treated by fixed appliances and the extraction of 16 and 26. The mean age at commencement was 13.2 ± 1.5 years. Lateral cephalograms were available pre-treatment (T1), immediately post-treatment (T2), and at 2.6 years post-treatment (T3). The sample was divided into hypodivergent (n = 18), normodivergent (n = 17), and hyperdivergent (n = 48) facial types. Mean increments, standard deviations, and 95% confidence intervals were calculated for T2–T1 and T3–T2. Increments were tested using paired-samples t-tests, and variables between groups by applying ANOVA followed by Tukey’s post hoc test. Linear regression was used to examine the effect of facial type, age, and gender.

Significant changes occurred during treatment for most cephalometric variables. Post-treatment, the growth pattern showed a tendency to return to the original form. Facial type had only a minor influence on cephalometric increments during and after treatment.

Post-treatment skeletal, soft tissue, and dentoalveolar changes were limited. Facial type had only a minor influence during and after treatment and care must be taken to control lower incisor inclination.

To investigate the prevalence of posterior tongue tie in orthodontic patients using numerical and clinical assessment methods in order to identify an association between posterior tongue tie and transverse maxillary deficiency.

Seventy-nine participants from an orthodontic clinic were divided into two groups. The first group of 44 patients exhibited a skeletally narrow maxilla and required maxillary skeletal expansion (MSE group) and 35 patients without a transverse discrepancy comprised a control group. Posterior tongue tie was examined by the Kotlow tongue tie classification, tongue range of motion ratio (TRMR) and via a clinical assessment. The prevalence of posterior tongue tie was compared between the two groups.

There was no significant difference in the level of the Kotlow classification grade between the two groups (p > 0.05) and the overall majority was diagnosed as normal. However, a higher proportion of posterior tongue tie was found in the MSE group than in the control group by clinical assessment (MSE group, 72.7%; control group, 42.9%; p = 0.005). The proportion of TRMR grade 2 was also higher in the MSE group than in the control group (p = 0.001). Of the subjects diagnosed with posterior tongue tie by clinical findings, approximately 94% showed TRMR grades 2 or 3.

A clinical assessment of posterior tongue tie was found to be simple and accurate, whereas a numerical assessment alone provided diagnostic difficulty. Considering the high prevalence of observed posterior tongue tie in the MSE group, there was a significant association between posterior tongue tie and transverse maxillary deficiency.

The alternative use of Orthodontic Miniscrew Implants (OMIs), traditionally used for skeletal anchorage, to facilitate micro-osteoperforations (MOPs) for accelerating orthodontic tooth movement has been reported in previous studies. The objective of the present in vitro study was to compare the microdamage generated by OMIs and MOP-purposed screws of similar dimensions in porcine cortical bone.

Forty rectangular porcine cortical bone specimens of 1.5 mm thickness were produced and divided into two equal groups. According to group allocation, either a single MOP screw or OMI was inserted and later removed. A sequential staining protocol was carried out to distinguish true microdamage created upon screw insertion and removal from iatrogenic damage. The bone specimens were imaged by a confocal laser scanning microscope, and five histomorphometric measurements described and quantified the generated microdamage.

On the entry (outer) bone surface, the OMI screws produced greater microdamage which reached statistical significance across all of the histomorphometric parameters. In contrast, a statistically significant increase in microdamage was created following MOP screw insertion on the exit (inner) bone surface, but only in three assessment parameters, recorded as total damage area, as well as diffuse damage area and radius.

Overall, the present study showed that 1.5 mm OMIs produced slightly greater microcrack-type and diffuse damage-type microdamage than the 1.6 mm diameter MOP screws. However, these differences were small and considered clinically insignificant.

The aim of this study was to determine the incidence of lateral incisor root resorption associated with impacted maxillary canines and determine predisposing factors that may be used to predict its occurrence.

Cone beam computerised tomographic images of 133 patients presenting with 186 impacted canines were examined for lateral incisor root resorption. A control sample consisted of 30 lateral incisors on the side of the non-impacted canine. The studied canine-associated variables were gender, type of impaction, location of the canine both meso-distally and vertically and the long axis angulation to the midline. Axial images were primarily used to diagnose resorption.

The estimated percentage of lateral root resorption in the sample was 17% (range 11.8– 23.9%) confirmed at a 95% confidence interval. A significant association was observed between the level of overlap of the canine across the lateral incisor, measured in sectors, and the probability of lateral incisor root resorption. The probability approximately doubled for each additional sector of canine overlap. No other significant association was noted related to all the other variables examined.

The incidence of lateral incisor root resorption associated with impacted maxillary canines was lower in the present study compared with many previous reports. However, resorption remains a common clinical finding. In order to screen for lateral incisor resorption, it is recommended that a cone beam image be prescribed when there is a mesial overlap of an impacted canine across the lateral incisor midline.