Orthodontic treatment in children and adolescent patients with X-linked hypophosphatemia: A case-control study.

OBJECTIVES: X-linked hypophosphatemia (XLH) is a rare genetic disease that disturbs bone and teeth mineralization. It also affects craniofacial growth and patients with XLH often require orthodontic treatment. The aim of this study was to describe changes in the dental health of XLH children during orthodontic treatment compared with those in matched controls undergoing similar orthodontic procedures. MATERIALS AND METHODS: For this retrospective case-control study, we included all individuals less than 16 years old diagnosed with XLH, orthodontically treated in our centre from 2016 to 2022 and pair-matched them to patients with no chronic or genetic conditions. Clinical and radiological parameters concerning their malocclusion, craniofacial discrepancy and the characteristics and iatrogenic effects of their orthodontic treatment were analysed. RESULTS: Fifteen XLH patients (mean age: 11.3 ± 2.1), pair-matched to 15 control patients were included. Orthodontic treatment was successfully conducted in XLH patients with slightly shorter duration and similar iatrogenic effects as in the control group, except for the occurrence of dental abscess during and after orthodontic tooth movement. XLH patients did not show more relapse than the controls. CONCLUSION: Despite the presence of oral manifestations of XLH such as spontaneous abscesses, XLH patients can undergo orthodontic treatment with no obvious additional iatrogenic effects.

Three-dimensional microanalysis of tooth movement during the first 6 months of orthodontic double retention.

INTRODUCTION: This study performed a 3-dimensional analysis of tooth movement during orthodontic retention to assess the effectiveness of double retention (fixed and removable) in preventing undesired tooth movement. METHODS: One hundred randomly selected patients were included at the initiation of double orthodontic retention with fixed retainers and vacuum-formed splints (recommended to be worn 22 h/d) in both arches. Intraoral scans were performed directly (T0), 1 month (n = 88), 3 months (T2) (n = 78), and 6 months (T3) (n = 66) after retainer bonding. Nine reference points were marked on each tooth in every patient. Subsequent scans were superimposed, and point displacement was calculated. Statistical analysis was performed using the R statistical software (version 4.2.2; R Core Team, Vienna, Austria). RESULTS: Sample size calculation determined at least 55 patients were needed. The total dropout between T0 and T3 was 34 patients (did not show up for appointment). The median absolute displacement value of a single point between T0 and T3 was 0.015 mm. The most stable teeth were mandibular central incisors, whereas the least stable were mandibular molars. Most tooth displacements occurred between T0 and T2, then slowed down significantly. CONCLUSIONS: Double orthodontic retention prevents major tooth displacements in most patients during the first 6 months of retention; however, larger, unpredictable single-tooth displacement may occur in individual patients.

A longitudinal study of the probability of developing malocclusion in children using a Bayesian analysis.

INTRODUCTION: This study evaluated the probability of developing malocclusions in mixed dentition. METHODS: A longitudinal study was conducted with 598 children (aged 5 years) in deciduous dentition. The children were followed for 3 years until mixed dentition (aged 8 years). Overjet, overbite, and transversal relations were evaluated. Bayesian models were used to analyze the data and estimate the parameters. RESULTS: The parameter θ was used for the distributions, indicating the probability of presenting a given condition with a credibility index (ICr) of 95%. After 3 years of follow-up, 121 children were reevaluated. The results showed that children have a high probability of malocclusion in mixed dentition. There was a higher probability of developing an increased overjet in the mixed dentition of 20.5% (ICr 95%, 13.6-28.4) to 48.3% (ICr 95%, 39.1-57.7) and a higher probability of having a normal overbite in the deciduous dentition and a lower probability in the mixed dentition (ICr 95%, 9.2-21.3). CONCLUSIONS: Considering the probabilistic model of Bayesian analysis, children with normal overjet in the deciduous dentition may show an increased overjet in the mixed dentition. Concerning overbite, children may present an anterior open bite during the transition between deciduous and mixed dentition, as well as self-correction of deep overbite in mixed dentition. Furthermore, they may present a posterior crossbite during the mixed dentition when there is a normal transverse relationship in the deciduous dentition.

Exploring etiologic contributions to the occurrence of external apical root resorption.

INTRODUCTION: External apical root resorption (EARR) is often an undesirable sequela of orthodontic treatment. Prior studies have suggested a substantial link between EARR and certain genetic components. Single nucleotide polymorphisms (SNPs) may play a role as predisposing factors. This study aimed to investigate the potential association between EARR and various SNPs. METHODS: The study included 218 orthodontic participants of all malocclusions who had available pretreatment and posttreatment panoramic radiographs. The most severely affected maxillary incisor on the radiograph was assessed for EARR using a 0-4 categorical scale. DNA was taken from the saliva samples of the participants, and the SNPs were analyzed using polymerase chain reaction and TaqMan chemistry. Statistical testing was performed to verify any associations with EARR (P <0.05). RESULTS: From all genes tested, the rs678397 SNP of ACT3N (P = 0.003) and the rs1051771 SNP of TSC2 (P = 0.03) were significantly associated with EARR. No association could be established between other polymorphisms and EARR. In addition, patients with Class III malocclusion and extended treatment times were at increased risk of developing EARR. CONCLUSIONS: Our results support the concept of gene polymorphisms as risk factors in EARR. In particular, a significant association was found between ACT3N and TSC2 and EARR. Clinically, predisposing risk factors for EARR should be assessed for each patient.

Advancing the assessment of pacifier effects with a novel computational method.

BACKGROUND: Numerous studies have demonstrated a high likelihood of malocclusions resulting from non-nutritive sucking. Consequently, quantifying the impact of pacifiers can potentially aid in preventing the development or exacerbation of malocclusions and guide the design of improved performance pacifiers. METHODS: This work proposes and assesses a computational methodology that can effectively gather crucial information and provide more precise data regarding the consequences of non-nutritive pacifier sucking. The computational framework utilized is based on solids4Foam [1, 2], a collection of numerical solvers developed within the OpenFOAM® computational library [3]. The computational model focuses on the palate of a six-month-old baby and incorporates various components such as palate tissues, pacifier and tongue, and considers the negative intraoral pressure generated and the tongue displacement. Different models were tested, each offering varying levels of detail in representing the palate structure. These models range from a simplified approach, with one tissue, to a more intricate representation, involving up to five different tissues, offering a more comprehensive palate model compared to existing literature. RESULTS: The analysis of results involved examining the distribution of stress on the palate surface, as well as the displacement and forces exerted on the dental crowns. By comparing the obtained results, it was possible to evaluate the precision of the approaches previously described in the literature. The findings revealed that the predictions were less accurate when using the simplified model with a single tissue for the palate, which is the most common approach proposed in the literature. In contrast, the results demonstrated that the palate model with the most intricate structure, incorporating five different tissues, yielded distinct outcomes compared to all other combinations. CONCLUSIONS: The computational methodology proposed, employing the most detailed palate model, has demonstrated its effectiveness and necessity in obtaining accurate data on the impact of non-nutritive sucking habits, which are recognized as a primary contributor to the development of dental malocclusions. In the future, this approach could be extended to conduct similar studies encompassing diverse pacifier designs, sizes, and age groups. This would foster the design of innovative pacifiers that mitigate the adverse effects of non-nutritive sucking on orofacial structures.

Effect of maxillary anterior supernumerary tooth extraction on the underlying malocclusion.

INTRODUCTION: Orthodontic discrepancies are a common finding in patients with supernumerary teeth (ST). The presence of a ST can cause a number of orthodontic discrepancies, including delayed eruption or retention of adjacent teeth, crowding, spacing, and abnormal root formation. The aim of the present study was to assess the effect of extraction of an anterior supernumerary tooth on the underlying orthodontic discrepancies without additional treatment for a 6-month period. METHODS: This was a prospective, longitudinal, observational, study. It included 40 participants with orthodontic malocclusions due to maxillary anterior supernumeraries. We examined the changes in the crowding and excessive space in the anterior and posterior segments on cast models. RESULTS: In the group that presented with crowding, a statistically significant decrease of 0.95 ± 0.17 mm (P < 0.001) was found between T0 and T1. Of the participants, three exhibited full self-correction. The excessive space at T0 (3.06 mm) decreased by 1.78 ± 0.19 mm to T1 (1.28 mm) in the anterior segment. Seven participants showed full self-correction of the diastemas after the 6-month observation period. CONCLUSION: The results imply that orthodontic treatment can be postponed for at least 6 months after the extraction of the supernumerary tooth as potential self-correction can be expected. This natural alleviation of the malocclusions may make the orthodontic treatment simpler, shorten the treatment time and decrease overall appliance wear time.

Infraocclusion in the Primary and Permanent Dentition-A Narrative Review.

The gradual movement of a tooth away from the occlusal plane is called infraocclusion or reinclusion. Reincluded teeth are most often deciduous molars, and permanent teeth are less frequently affected. Depending on the level of the infraocclusion, the severity of the disorder is classified as mild, moderate, or severe. The etiology of the phenomenon is not fully known. Tooth submerging can lead to serious complications, such as abnormal position of adjacent teeth, displacement of the bud of the permanent successor, shortening of the dental arch, or developmental disturbances of alveolar process. Early diagnosis of the tooth infraocclusion and regular monitoring of its progression help to avoid serious permanent sequelae. The treatment of reinclusion often involves only observation. However, in some cases, the therapeutic procedure requires interdisciplinary treatment by specialists from various fields of dentistry. This study presents current methods of diagnosis and treatment of patients with submerged teeth.

Effects of non-nutritive sucking habits on malocclusions: a systematic review.

The development of the craniomandibular system is guided by genetic interactions and environmental factors, including specific habits such as breastfeeding, bottle feeding, thumb sucking and the use of pacifiers. These habits can have a considerable impact on the growth of the developing jaws and can lead to malocclusion in children. This review aims to investigate potential associations between non-nutritive sucking habits (NNSHs) and malocclusions compared to the presence of nutritive sucking habits (NSHs). To carry out this systematic review, we followed the PRISMA protocol and performed a bibliographic search of the existing literature until April 2023 in the following electronic databases: Medline, PubMed, The Cochrane Library and Embase. Out of a total of 153 records, we included 21 studies. We found that the chances of diagnosing a malocclusion were higher for children with bottle nutrition when compared to breast-fed children. Breastfeeding provides protection against malocclusions. In the same manner, persistent NNSH habits appeared to be associated with increased chances of having malocclusions. The longer the child was breastfed, the shorter the duration of the pacifier habit and the lower the risk of developing moderate/severe malocclusions. The duration of the habits has a positive influence on the appearance of occlusion defects.

[Fractures of the mandibular condyle]. / Fracturen van het collum mandibulae.

A fracture of the mandibular condyle is a common fracture of the mandible. After the diagnosis has been made, there are various treatment options: wait and see, conservative or surgical. Which of these treatment options is best depends on several different factors and is often the subject of debate. A common complication of a fracture of the mandibular condyle is malocclusion. Malocclusion can cause problems - even in the long term - for which the patient often requires secondary treatment.

Non-surgical adjunctive interventions for accelerating tooth movement in patients undergoing orthodontic treatment.

BACKGROUND: Deviation from a normal bite can be defined as malocclusion. Orthodontic treatment takes 20 months on average to correct malocclusion. Accelerating the rate of tooth movement may help to reduce the duration of orthodontic treatment and associated unwanted effects including orthodontically induced inflammatory root resorption (OIIRR), demineralisation and reduced patient motivation and compliance. Several non-surgical adjuncts have been advocated with the aim of accelerating the rate of orthodontic tooth movement (OTM).         OBJECTIVES: To assess the effect of non-surgical adjunctive interventions on the rate of orthodontic tooth movement and the overall duration of treatment. SEARCH METHODS: An information specialist searched five bibliographic databases up to 6 September 2022 and used additional search methods to identify published, unpublished and ongoing studies. SELECTION CRITERIA: We included randomised controlled trials (RCTs) of people receiving orthodontic treatment using fixed or removable appliances along with non-surgical adjunctive interventions to accelerate tooth movement. We excluded split-mouth studies and studies that involved people who were treated with orthognathic surgery, or who had cleft lip or palate, or other craniofacial syndromes or deformities. DATA COLLECTION AND ANALYSIS: Two review authors were responsible for study selection, risk of bias assessment and data extraction; they carried out these tasks independently. Disagreements were resolved by discussion amongst the review team to reach consensus.  MAIN RESULTS: We included 23 studies, none of which were rated as low risk of bias overall. We categorised the included studies as testing light vibrational forces or photobiomodulation, the latter including low level laser therapy and light emitting diode. The studies assessed non-surgical interventions added to fixed or removable orthodontic appliances compared to treatment without the adjunct. A total of 1027 participants (children and adults) were recruited with loss to follow-up ranging from 0% to 27% of the original samples.  Certainty of the evidence For all comparisons and outcomes presented below, the certainty of the evidence is low to very low. Light vibrational forces  Eleven studies assessed how applying light vibrational forces (LVF) affected orthodontic tooth movement (OTM). There was no evidence of a difference between the intervention and control groups for duration of orthodontic treatment (MD -0.61 months, 95% confidence interval (CI) -2.44 to 1.22; 2 studies, 77 participants); total number of orthodontic appliance adjustment visits (MD -0.32 visits, 95% CI -1.69 to 1.05; 2 studies, 77 participants); orthodontic tooth movement during the early alignment stage (reduction of lower incisor irregularity (LII)) at 4-6 weeks (MD 0.12 mm, 95% CI -1.77 to 2.01; 3 studies, 144 participants), or 10-16 weeks (MD -0.18 mm, 95% CI -1.20 to 0.83; 4 studies, 175 participants); rate of canine distalisation (MD -0.01 mm/month, 95% CI -0.20 to 0.18; 2 studies, 40 participants); or rate of OTM during en masse space closure (MD 0.10 mm per month, 95% CI -0.08 to 0.29; 2 studies, 81 participants). No evidence of a difference was found between LVF and control groups in rate of OTM when using removable orthodontic aligners. Nor did the studies show evidence of a difference between groups for our secondary outcomes, including patient perception of pain, patient-reported need for analgesics at different stages of treatment and harms or side effects.  Photobiomodulation Ten studies assessed the effect of applying low level laser therapy (LLLT) on rate of OTM. We found that participants in the LLLT group had a statistically significantly shorter length of time for the teeth to align in the early stages of treatment (MD -50 days, 95% CI -58 to -42; 2 studies, 62 participants) and required fewer appointments (-2.3, 95% CI -2.5 to -2.0; 2 studies, 125 participants). There was no evidence of a difference between the LLLT and control groups in OTM when assessed as percentage reduction in LII in the first month of alignment (1.63%, 95% CI -2.60 to 5.86; 2 studies, 56 participants) or in the second month (percentage reduction MD 3.75%, 95% CI -1.74 to 9.24; 2 studies, 56 participants). However, LLLT resulted in an increase in OTM during the space closure stage in the maxillary arch (MD 0.18 mm/month, 95% CI 0.05 to 0.33; 1 study; 65 participants; very low level of certainty) and the mandibular arch (right side MD 0.16 mm/month, 95% CI 0.12 to 0.19; 1 study; 65 participants). In addition, LLLT resulted in an increased  rate of OTM during maxillary canine retraction (MD 0.01 mm/month, 95% CI 0 to 0.02; 1 study, 37 participants). These  findings were not clinically significant. The studies showed no evidence of a difference between groups for our secondary outcomes, including OIIRR, periodontal health and patient perception of pain at early stages of treatment. Two studies assessed the influence of applying light-emitting diode (LED) on OTM. Participants in the LED group required a significantly shorter time to align the mandibular arch compared to the control group (MD -24.50 days, 95% CI -42.45 to -6.55, 1 study, 34 participants). There is no evidence that LED application increased the rate of OTM during maxillary canine retraction (MD 0.01 mm/month, 95% CI 0 to 0.02; P = 0.28; 1 study, 39 participants ). In terms of secondary outcomes, one study assessed patient perception of pain and found no evidence of a difference between groups.   AUTHORS' CONCLUSIONS: The evidence from randomised controlled trials concerning the effectiveness of non-surgical interventions to accelerate orthodontic treatment is of low to very low certainty. It suggests that there is no additional benefit of light vibrational forces or photobiomodulation for reducing the duration of orthodontic treatment. Although there may be a limited benefit from photobiomodulation application for accelerating discrete treatment phases, these results have to be interpreted with caution due to their questionable clinical significance. Further well-designed, rigorous RCTs with longer follow-up periods spanning from start to completion of orthodontic treatment are required to determine whether non-surgical interventions may reduce the duration of orthodontic treatment by a clinically significant amount, with minimal adverse effects.

Incompetent lip seal and nail biting as risk factors for malocclusion in Japanese preschool children aged 3-6 years.

BACKGROUND: Malocclusion is a multifactorial condition associated with genetic and environmental factors. The purpose of this study was to investigate the prevalence of occlusal traits, oral habits, and nose and throat conditions by age and to assess the association between malocclusion and its environmental factors in Japanese preschool children. METHODS: A total of 503 Japanese children (258 boys and 245 girls aged 3-6 years) were recruited. Occlusal traits were assessed visually to record sagittal, vertical, and transverse malocclusion, and space discrepancies. Lip seal was recorded by an examiner, and oral habits (finger sucking, lip sucking or lip biting, nail biting, chin resting on a hand) and nose and throat conditions (tendency for nasal obstruction, allergic rhinitis, palatine tonsil hypertrophy) were assessed by a questionnaire completed by the parents. The prevalence of each item was calculated, and binary logistic regression was used to examine the factors related to malocclusion. RESULTS: 62.0% of preschool children in the present study exhibited malocclusion, and 27.8% exhibited incompetent lip seal. Nail biting was the most frequent oral habit with a prevalence of 18.9%. Nasal obstruction was recorded in 30.4% of children. The results of binary logistic regression showed that incompetent lip seal was significantly related to malocclusion, and that nail biting was significantly negatively related. CONCLUSIONS: Incompetent lip seal is significantly associated with malocclusion, but nail biting may not necessarily be a deleterious habit for the occlusion in Japanese preschool children.

Treatment for Adult Mandibular Condylar Process Fractures: A Network Meta-Analysis of Randomized Clinical Trials.

PURPOSE: Using network meta-analyses (NMA) has become increasingly valuable as it enables the comparison of interventions that have not been directly compared in a clinical trial. To date, there has not been a NMA of randomized clinical trials (RCT) that compares all types of treatments for mandibular condylar process fractures (MCPFs). The aim of this NMA was to compare and rank all the available methods used in the treatment of MCPFs. METHODS: Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, a systematic search was conducted in 3 major databases up to January 2023 to retrieve RCTs that compared various closed and open treatment methods for MCPFs. The predictor variable is treatment techniques: arch bars (ABs) + wire maxillomandibular fixation (MMF), rigid MMF with intermaxillary fixation screws, AB + functional therapy with elastic guidance (AB functional treatment), AB rigid MMF/functional treatment, single miniplate, double miniplate, lambda miniplate, rhomboid plate, and trapezoidal miniplate. Postoperative complications were the outcome variables and included occlusion, mobility, and pain, among other things. Risk ratio (RR) and standardized mean difference were calculated. Version 2 of the Cochrane risk-of-bias tool and Grading of Recommendations, Assessment, Development, and Evaluations system were used to determine the certainty of the results. RESULTS: The NMA included a total of 10,259 patients from 29 RCTs. At ≤6 months, the NMA revealed that the use of 2-miniplates significantly reduced malocclusion compared to rigid MMF (RR = 2.93; confidence interval [CI]: 1.79 to 4.81; very low quality) and functional treatment (RR = 2.36; CI: 1.07 to 5.23; low quality).Further, at ≥6 months, 2-miniplates resulted in significantly lower malocclusion compared to rigid MMF with functional treatment (RR = 3.67; CI: 1.93 to 6.99; very low quality).Trapezoidal plate and AB functional treatment were ranked as the best options in 3-dimensional (3D) plates and closed groups, respectively.3D-miniplates (very low-quality evidence) were ranked as the most effective treatment for reducing postoperative malocclusion and improving mandibular functions after MCPFs, followed closely by double miniplates (moderate quality evidence). CONCLUSIONS: This NMA found no substantial difference in functional outcomes between using 2-miniplates versus 3D-miniplates to treat MCPFs (low evidence).However, 2-miniplates led to better outcomes than closed treatment (moderate evidence).Additionally, 3D-miniplates produced better outcomes for lateral excursions, protrusive movements, and occlusion than closed treatment at ≤6 months (very low evidence).

Mandibular condylar hyperplasia and its correlation with vascular endothelial growth factor.

BACKGROUND: Condylar hyperplasia (CH) is a rare condition characterised by excessive unilateral growth of the mandibular condyle after cessation of growth on the contralateral side causing facial asymmetry, being more prevalent in the second and third decades. OBJECTIVE: The aim of this study was to determine the utility of vascular endothelial growth factor (VEGF-A) as a diagnostic and prognostic factor in condylar hyperplasia, and to determine its potential viability as a therapeutic target. METHODS: This is a case-control study, where 17 mandibular condyles specimens were collected from 17 patients treated for active mandibular condyle hyperplasia and three unaffected human mandibular condyles from cadavers will serve as the control group. The samples were immunostained with VEGF-A antibody and evaluated on both quantity and intensity of staining. RESULTS: VEGF-A was qualitatively found to be greatly upregulated in patients with condylar hyperplasia. CONCLUSION: VEGF-A was qualitatively found to be upregulated in patients affected by CH, validating VEGF-A as a potential diagnostic, prognostic and therapeutic target.

Effectiveness of platelet-rich concentrates on the rate of orthodontic tooth movement: a systematic review and meta-analysis.

BACKGROUND: Autologous platelet-rich concentrates (PRCs) are recently used as a local biological substance in orthodontics to accelerate the rate of tooth movement. OBJECTIVES: This systematic review aimed to evaluate the effects of PRCs on the rate of orthodontic tooth movement (OTM). SEARCH METHODS: Unrestricted search of five electronic databases supplemented by the manual and gray literature search were undertaken in March 2022. SELECTION CRITERIA: Randomized controlled trials (RCTs) evaluating the effect of PRCs on the rate of OTM with their side effect were included in this systematic review. DATA COLLECTION AND ANALYSIS: Data items were extracted by two authors using a pre-piloted extraction form. Similar outcomes within a comparable time frame were synthesized in a meta-analysis. RESULTS: Fourteen studies were deemed eligible for inclusion and seven RCTs were pooled in a meta-analysis. Canine retraction rate was higher in the side of PRCs injection than the control side by 0.28 mm/month (95% CI: 0.16-0.40, I2 = 95.6 per cent, P < 0.001, 345 patients) in the first 4 months after PRCs injection. There was no statistically significant difference between the PRCs side and the control side regarding molar anchorage loss (MAL) (MD = 0.03 mm, 95% CI: -0.18 to 0.24, I2 = 46.3 per cent, P = 0.78, 44 patients), canine rotation (MD = -0.19o, 95% CI: -1.95 to 1.57, I2 = 45.4 per cent, P = 0.96, 48 patients), or en-masse retraction. Likewise, there was no difference between both groups in terms of the duration of de-crowding. The mandibular canine retraction was statistically higher on the PRCs side than on the control side by 0.17 mm/month (P < 0.001, one trial). Regarding root resorption, there was no statistically significant difference between the experimental and control sides within the follow-up time. Mild pain scores were reported by the patients in the first 24 hours after injections. CONCLUSIONS: Low-level evidence indicates that the effect of PRCs on OTM is minor and clinically insignificant. The findings should be interpreted with caution due to the inherent limitations in the included RCTs. REGISTRATION: PROSPERO (CRD42022300026).

Anterior open bite self-correction after cessation of non-nutritive sucking habits: a systematic review.

BACKGROUND: Non-nutritive sucking habits likely may cause occlusal changes such as anterior open bite (AOB) if they persist over extended time. OBJECTIVES: To assess if there is self-correction of AOB after cessation of non-nutritive sucking habits in children older than 4 years old, through a systematic review. SEARCH METHODS: Data sources included PubMed, Scopus, Web of Science and Latin American and Caribbean Health Sciences (LILACS) databases, gray literature as Google Scholar, the database System for Information on Gray Literature in Europe (OpenGrey) and ProQuest Dissertations and Theses Database, also hand searches of the included studies references. SELECTION CRITERIA: Studies assessing occlusal changes in children aged 4-12 years with AOB traits and non-nutritive sucking habits after the discontinuation of the habit were included. DATA COLLECTION AND ANALYSIS: Two authors independently assessed eligibility and extracted data. The risk of bias was assessed using the Newcastle-Ottawa Quality Assessment Scale and the Joanna Briggs Critical Appraisal Checklist for quasi-experimental studies. The confidence in cumulative evidence was assessed using the GRADE criteria. RESULTS: Over 3100 studies, only 5 met the inclusion criteria. There is often self-correction of AOB after discontinuing the non-nutritive sucking habit, even in cases older than 4 years old. The improvement ranged between 50 and 100%. The overall quality of evidence was very low. CONCLUSIONS: AOB self-correction after discontinuing a non-nutritive sucking habit is possible, even after 4 years old, although with very low certainty in the body of evidence. It is not clear after what age the removal from the habit is unlikely to facilitate AOB self-correction. REGISTRATION AND CONFLICT OF INTEREST: International Prospective Register of Systematic Reviews code: CRD42016052171. There was no conflicting interest from the review authors.

Under pressure-mechanisms and risk factors for orthodontically induced inflammatory root resorption: a systematic review.

BACKGROUND: The application of orthodontic forces causes root resorption of variable severity with potentially severe clinical ramifications. OBJECTIVE: To systematically review reports on the pathophysiological mechanisms of orthodontically induced inflammatory root resorption (OIIRR) and the associated risk factors based on in vitro, experimental, and in vivo studies. SEARCH METHODS: We undertook an electronic search of four databases and a separate hand-search. SELECTION CRITERIA: Studies reporting on the effect of orthodontic forces with/without the addition of potential risk factors on OIIRR, including (1) gene expression in in-vitro studies, the incidence root resorption in (2) animal studies, and (3) human studies. DATA COLLECTION AND ANALYSIS: Potential hits underwent a two-step selection, data extraction, quality assessment, and systematic appraisal performed by duplicate examiners. RESULTS: One hundred and eighteen articles met the eligibility criteria. Studies varied considerably in methodology, reporting of results, and variable risk of bias judgements.In summary, the variable evidence identified supports the notion that the application of orthodontic forces leads to (1) characteristic alterations of molecular expression profiles in vitro, (2) an increased rate of OIIRR in animal models, as well as (3) in human studies. Importantly, the additional presence of risk factors such as malocclusion, previous trauma, and medications like corticosteroids increased the severity of OIIRR, whilst other factors decreased its severity, including oral contraceptives, baicalin, and high caffeine. CONCLUSIONS: Based on the systematically reviewed evidence, OIIRR seems to be an inevitable consequence of the application of orthodontic forces-with different risk factors modifying its severity. Our review has identified several molecular mechanisms that can help explain this link between orthodontic forces and OIIRR. Nevertheless, it must be noted that the available eligible literature was in part significantly confounded by bias and was characterized by substantial methodological heterogeneity, suggesting that the results of this systematic review should be interpreted with caution. REGISTRATION: PROSPERO (CRD42021243431).

The effect of micro-osteoperforation on the rate of tooth movement during the alignment stage in patients with mandibular crowding: a randomised controlled trial.

BACKGROUND: Orthodontic treatment is a long process that requires patient cooperation. Risks of side effects such as caries formation, periodontal problems, and root resorption increases as well as problems in patient cooperation arises with longer treatments. Several different techniques were developed that may shorten the treatment time. OBJECTIVE: The aim of this study was to evaluate the effectiveness of micro-osteoperforations (MOPs) performed during the alignment stage. TRIAL DESIGN: Randomized controlled trial. METHODS: Twenty-eight subjects who had crowding in the mandibular arch were included in the study. The first group (4 boys and 10 girls, mean age = 17.21 ± 3.76 years) was treated with MOP (MOP) and the second group (8 boys and 6 girls, mean age = 15.29 ± 1.77 years) was treated without MOP (control). Cephalometric variables, periodontal parameters, Little irregularity index, alignment duration, patient satisfaction, and ease of operation were evaluated. The level of statistical significance was P ≤ 0.05. RESULTS: Alignment duration was shorter (P = 0.000) in the MOP group (105.57 ± 18.34 days) compared to control group (135.86 ± 15.12 days). Alleviating of the crowding was more in the MOP group, compared to the control group in all time points. The pain level in the MOP group in the first appointment was higher compared to control group (P = 0.002). There was no significant difference between the groups in cephalometric parameters. Higher increases were found for gingival index (P = 0.008) and bleeding index (P = 0.039) in the control group compared to MOP group at the end of treatment. LIMITATIONS: The study was a single-centre study. CONCLUSION: Alignment stage was shortened with MOP application. There was no difference between groups for patient satisfaction and pain level except for the first appointment. No difference was observed between the groups regarding cephalometric values. Clinically insignificant inflammation was observed in periodontal tissues for both groups. REGISTRATION: This study was registered at the Clinical Trials Registry (ClinicalTrials.gov NCT03652454).

Influence of bad oral habits upon the development of posterior crossbite in a preschool population.

BACKGROUND: A study is made of posterior crossbite in deciduous dentition and its possible association to extrinsic factors (bad oral habits). METHODS: A total of 1168 Spanish children between 3 and 6 years of age were included in the study. Exploration of the oral cavity was performed to assess the presence of crossbite (uni- or bilateral and/or functional), and a questionnaire was administered to the parents or caregivers to determine the presence of bad oral habits and their duration. RESULTS: In occlusion, 19.7% of the cases (n = 230) presented uni- or bilateral posterior crossbite. On adopting centric relation confronting the midlines, crossbite persisted in 165 children, indicating that 65 cases were due to premature contacts (functional crossbite). The identified favoring factors were pacifier use, thumb sucking, oral breathing and tongue thrusting or immature swallowing. DISCUSSION: Most studies in the literature report a relationship between posterior crossbite and bad oral habits. The proportion of posterior crossbites identified in our study (16.6%) is consistent with the data published by authors such as Kobayashi, Limeira or Paolantonio, among others, but differs from the results of Zhifei Zhou, Peres or Germa. In coincidence with most studies, we recorded a statistically significant association between posterior crossbite and bad oral habits. CONCLUSIONS: Bad oral habits favor the appearance of posterior crossbite, and the duration of the habit, its intensity (in the case of thumb sucking) and type (in the case of pacifier use) act as influencing factors. Functional study characterized the types of posterior crossbites and identified those attributable to premature contacts. This aspect has not been addressed by previous studies, and we consider the findings to be very interesting for analyzing and identifying the features of true crossbites.

Orthodontic treatment of traumatically avulsed maxillary central incisors with bimaxillary dentoalveolar protrusion in an adult female: a case report.

BACKGROUND: Clinicians agree that obtaining and retaining good treatment results for missing maxillary central incisors owing to trauma is not easy. Management of adult patients with permanent maxillary central incisor loss who visit the clinic with high expectations for aesthetics and function pose a significant diagnostic dilemma. Therefore, esthetic and functional outcomes should be taken into consideration when deciding the proper treatment method. The treatment described in this study aimed to reestablish smile esthetics by proposing an effective multidisciplinary clinical approach that includes orthodontic-prosthetic-periodontal procedures, optimally reduced lip protrusion, center dental midlines, and establishment of stable occlusion. CASE PRESENTATION: The patient was a 19-year-old adult female with bimaxillary arch protrusion who had been wearing removable dentures for several years since the loss of her maxillary central permanent incisors. A multidisciplinary treatment including the extraction of two mandibular primary premolars was adopted. The treatment plan consisted of orthodontic space closure by shifting the adjacent teeth towards the central incisor spaces combined with appropriate morphologic remodeling and gingival reshaping to obtain good aesthetic and functional results. The duration to complete the orthodontic treatment was 35 months. Clinical and radiographic results after treatment suggested smile harmony with an improvement in the facial profile, good function of the occlusion, and a positive effect on bone remodeling in the area of the missing incisors during orthodontic tooth movement. CONCLUSIONS: This clinical case illustrated the necessity for using multidisciplinary methods involving orthodontic, prosthodontic, and periodontic procedures to treat an adult female patient with bimaxillary arch protrusion and long-term absence of anterior teeth due to severe trauma.

Reflection on patients' experience with orthodontic appliances wear and its impact on oral health related quality of life: observational comparative study.

BACKGROUND: The objective of this study was to explore and compare patient's experience with the use of a removable functional appliance or fixed orthodontic appliance and its influence on oral health-related quality of life. MATERIAL AND METHODS: This clinical trial included 81 participants having Class II Division 1 and age ranging between 10 and 16 years. The participants were included in any of a three equal groups according to the set inclusion and exclusion criteria; Group 1: patients treated with a Twin-Block functional appliance; Group 2: patients treated with a fixed orthodontic appliance only; and Group 3 (control group): patients not in orthodontic treatment yet. The COHIP SF-19 was used. Patients were given the questionnaire as follows: Group 1: (1) after at least 8 months from starting treatment; (2) after completing phase 1 by 2-3 months without wearing the appliance; Group 2: (1) just before debonding; (2) after finishing the treatment by 2-3 months without any appliances; and Group 3: (1) at the patient's first visit to the orthodontic clinic; (2) after 2-3 months from the first visit to the orthodontic clinic and before starting any treatment. RESULTS: The 81 participants were 31 males and 50 females with median age of 13 years. The total COHIP SF-19 scores at baseline were 57 (49-64), 67 (63-72), and 47 (42-53) for the Twin-Block, the fixed appliance, and the malocclusion groups, respectively. Two-month mean scores adjusted to the baseline scores were 64.82 ± 1.15, 65.65 ± 1.47, and 54.45 ± 1.44 for the Twin-Block, the fixed appliance, and the malocclusion groups, respectively. CONCLUSIONS: Both at baseline and two-months (adjusted to the baseline scores), participants in the malocclusion group showed compromised socio-emotional quality of life and reported the poorest total OHRQoL. At the baseline, better socio-emotional and total OHRQoL was reported by the fixed appliance group compared to the Twin-Block group but, after two months both groups gave similar sores. Therefore; patients' perceptions about their experience with the orthodontic appliance might change.