Effectiveness of orthopaedic treatments on the enlargement of the upper airways: Overview of systematic reviews.

OBJECTIVE: The aims of this overview are to evaluate the three-dimensional effects of orthopaedic treatment (OT) and myofunctional therapy (MT) on the enlargement of the upper airways (UA). METHODS: A search of the MEDLINE/PubMed and EMBASE databases was conducted up to July 2022 and completed by hand search. After selection of the title and abstract, systematic reviews (SR) dealing with the impact of OT and/or MT on UA containing only controlled studies were included. The methodological quality of the SR was assessed by the AMSTAR-2, Glenny and ROBIS tools. A quantitative analysis was done with Review Manager 5.4.1. RESULTS: Ten SR were included. The risk of bias was judged low for one SR according to ROBIS. Two SR presented a high level of evidence according to AMSTAR-2. In the quantitative analysis and about the orthopaedic mandibular advancement therapies (OMA), while a significant increase in superior (SPS) [(Mean difference (MD): 1.19; CI 95% [0.59; 1.78]; P<0.0001)] and middle (MPS) pharyngeal space [(MD: 1.10; CI 95% [0.22; 1.98]; P=0.01)] existed in the short-term for both OMA, it was greater for removable. On the other hand, there was no significant change in the inferior pharyngeal space (IPS). Four other SR targeted the short-term efficacy of class III OT. Only treatments with face mask (FM) or face mask+rapid maxillary expansion (FM+RME) allowed a significant increase in SPS [(MD FM: 0.97; CI 95% [0.14; 1.81]; P=0.02/MD FM+RME: 1.54; CI 95% [0.43; 2.66]; P=0.006)]. This was neither the case for chin cup nor in all cases in IPS. The last two SR explored the effectiveness of RME, whether or not associated with bone anchorage, on the dimensions of the UA or on the reduction of the apnoea/hypopnea index (AHI). A significant superiority of the effects of the devices with mixed or only bone anchorages existed concerning the width of the nasal cavity, the nasal airflow and the reduction of the nasal resistance. But, the qualitative analysis showed no significant reduction in AHI after RME. CONCLUSIONS: Despite the heterogeneity of the included systematic reviews and their unfortunately not always low risk of bias, this synthesis showed that orthopaedics could provide some short-term improvement in AU dimensions, mainly in the upper and middle areas. Indeed, no devices improved the IPS. Class II orthopaedics improved SPS and MPS; class III orthopaedics, except for the chin cup, improved only SPS. RME, optimised with bone or mixed anchors, mostly improved the nasal floor.

Ortho- perio- prosthetic interdisciplinary approach of an adult class II division 2 with multiple premolar agenesis: A case report.

The aim of this case report is to illustrate the fixed orthodontic, surgical and periodontal implant management of a young adult with multiple agenesis associated with a class II division 2 malocclusion. The challenge here was the multidisciplinary synchronisation in order to achieve a coordinated treatment with the best possible aesthetic, prosthetic and functional prognosis. The patient suffered from a total of 10 agenesis including third molars and underwent implant replacement with bone grafting and periodontal planning of the 6 missing premolars. The orthodontic treatment lasted 22months and was followed by a period of just under a year for periodontal and implant prosthetic completion. The 3-year follow-up after the orthodontic phase showed an excellent prognosis in terms of aesthetics, function and stability.

Lingual treatment of an adult patient with an iatrogenic class II anterior open bite: Report of a case with a non-surgical orthodontic approach.

INTRODUCTION: The treatment of adult patients presenting an open bite is a real challenge for orthodontists due to the complexity of the malocclusion. The diagnosis is essential to identify aetiological factors and establish the best aesthetic and functional therapeutic prognosis. Among the aetiological factors, iatrogenic treatment history has to be considered. It is the case here where a regrettable unsuitable splint for bruxism treatment forced an open bite to appear. MATERIAL AND METHOD: This case report presents an adult women with a large open bite due to an occlusal splint not covering the last mandibular molars. It was not really a vertical skeletal excess but more a mandibular clockwise rotation linked to the molar extrusions, which created a dento-alveolar open bite and labio-mental contractions during lip closure. Treatment objectives were the intrusion of the third and second molars, the extrusion of incisors to obtain a counter clockwise mandibular rotation. The patient was treated with an aesthetic and customized lingual appliance with no orthognathic surgery. A physiotherapy was followed by the patient when the open bite was closed in order to facilitate and stabilize the intercuspation. RESULTS: A complete closing of the open bite was reached after two years of treatment. The superimposition showed the anticlockwise mandibular rotation. The levelling with posterior intrusion and the incisors extrusion reduced the vertical dimension with success. After 3years of retention, the occlusal stability was obtained. CONCLUSION: The intrusion of the molars associated with a counter clockwise mandibular rotation made it possible the incisor extrusion. The occlusal balance with physiotherapy and patient compliance maintained the closure. In this way, the iatrogenic effects of the poorly designed bite splint were repaired.

Is the Quad Helix more efficient to correct mandibular asymmetry before age 7? A retrospective comparative study.

INTRODUCTION: Unilateral posterior crossbite (UPCB), often from dysfunctional and para-functional causes, leads to positional mandibular asymmetries that can develop at a very young age into skeletal mandibular deviation; hence the interest of early maxillary expansion. The purpose of this retrospective study was to compare the impact of maxillary expansion by Quad Helix (QH) on mandibular skeletal asymmetry correction before and after 7 years of age. MATERIALS AND METHODS: All children with UPCB and skeletal mandibular asymmetry, who were treated by QH in the orthodontic department of Montpellier between February 2017 and August 2018 and had a radiography file at baseline (T0) and 12 months later (T1) were retrospectively included. The patients were divided into two groups according to age: under 7 years of age with QH adjusted on second primary molars (early group G1) and over up to 13 years old with QH adjusted on first permanent molars (late group G2). The differences between the right and left sides of the mandible in corpus length ΔL (main eligibility criterion) and ramus height ΔH (secondary criterion) were compared between groups. X2 test, Fisher's exact test and Wilcoxon rank-sum tests were used for baseline comparisons. A multifactorial analysis allowing adjustment on possible confounding factors was used with R software. RESULTS: Out of 67 patients files only 40 were completed and analysed: 13 in G1 and 27 in G2. These groups were comparable at baseline except for the age parameter. Taking into account the initial severity of asymmetry, the analysis of covariance showed a significant intergroup difference with higher correction in the early group of the corpus asymmetry (+1.0; P=0.008). On the contrary, no significant differences were observed between the groups in the ramus asymmetry correction. CONCLUSIONS: Within the limits of this retrospective study, the early unilateral posterior occlusion correction by QH can better reduce both positional and contour mandibular asymmetries in patients under 7 years of age.

Incorrect measurements and misleading conclusions in the article "Comparison of the efficacy of tooth alignment among lingual and labial brackets: an in vitro study".

BACKGROUND/OBJECTIVE: To reproduce the methods and results of the study by Alobeid et al. (2018) in which the efficacy of tooth alignment using conventional labial and lingual orthodontic bracket systems was assessed. MATERIALS/METHODS: We used the identical experimental protocol and tested (i) regular twin bracket (GAC-Twin [Dentsply]) and lingual twin bracket systems (Incognito [3M]), (ii) together with NiTi 0.014" wires (RMO), and (iii) a simulated malocclusion with a displaced maxillary central incisor in the x-axis (2 mm gingivally) and in the z-axis (2 mm labially). RESULTS: The method described by Alobeid et al. (2018) is not reproducible, and cannot be used to assess the efficacy of tooth alignment in labial or lingual orthodontic treatment. Major flaws concern the anteroposterior return of the Thermaloy-NiTi wire ligated with stainless steel ligatures. The reproduced experimental setting showed that a deflected Thermaloy-NiTi wire DOES NOT move back at all to its initial stage (= 0 per cent correction) because of friction and binding (see supplemented video), neither with the tested labial nor with the lingual brackets. Furthermore, an overcorrection of up to 138 per cent, which the authors indicate for some labial bracket-wire combinations and which deserves the characterization "irreal", stresses the inappropriateness of the method of measurement.Further flaws include: a) incorrect interpretation of the measurement results, where a tooth tripping around (overcorrection) is interpreted as a better outcome than a perfect 100 per cent correction; b) using a statistical test in an inappropriate and misleading way; c) uncritical copying of text passages from older publications to describe the method, which do not correspond to this experimental protocol and lead to calculation errors; d) wrong citations; e)differences in table and bar graph values of the same variable; f) using a lingual mushroom shaped 0.013" Thermaloy-NiTi wire which does not exist; g) drawing uncritical conclusions of so called "clinical relevance" from a very limited in vitro testing. CONCLUSIONS: Clinical recommendations based on in vitro measurements using the Orthodontic Measurement and Simulation System (OMSS) should be read with caution.

A genetic heritage; the same yet different: A comparative study in twins.

Since the 19th century, and in every field of medicine, monozygotic twins have been studied to assess the involvement of genetic and environmental factors in phenotypic expression. The phenotype/genotype relationship remains the leading problem in contemporary biology. In dentofacial orthopedics, this relationship is of relevance in the three-dimensional approach to the face, in both diagnosis and treatment. The present study of two monozygotic twins presenting skeletal class III malocclusions which were genetic yet different is a clear illustration of the interaction of genotype and epigenetic factors with environmental influences. We will demonstrate that treatment can reduce phenotypic differences.

Interaction between unilateral transverse disorders and the sagittal dimension: What measures are needed?

Dysfunctional deviations such as dysfunctional swallowing and chewing manifest as transverse arch discrepancies giving rise to positional asymmetry of the condyles and glenoid fossae with a more or less significant skeletal impact. This results almost inevitably in asymmetric occlusion in the sagittal dimension. Drawing on clinical cases, we will show which treatment strategies to adopt and which occlusal criteria to observe for finishing and stability.

Predictive factors for resorption of teeth adjacent to impacted maxillary canines.

PURPOSE: The aim of this study was to assess the link between the degree of resorption of teeth adjacent to an impacted maxillary canine and the situation of the latter so as to identify factors predictive of resorption. MATERIAL AND METHODS: This was a retrospective study concerning all patients with impacted maxillary canines who consulted the orthodontics department at the Center for dental care, teaching and research (CSERD) in Montpellier between 2010 and 2015, with a full radiological file including panorex, periapical long-cone and cone-beam images. In all, 25 patients with 31 impacted maxillary canines were analyzed. Measurements were made by a single operator using 2D images and 3D analysis; they concerned the quantitative and qualitative aspects of resorption of teeth adjacent to the impacted canines and also evaluation of the position of the maxillary canine and its follicular sac. The X2 test was used to compare percentage resorption in men and women. Analysis of variance (ANOVA) was applied to compare the average degree of resorption of the adjacent teeth depending on the sagittal or vertical position of the impacted maxillary canine. Covariance analysis (ANCOVA) was used to study the average degree of resorption taking jointly into account the sagittal, vertical and transverse positions and adjusting for age and sex. Calculations were performed with a significance threshold of 5% using MyStat® software. RESULTS: Women made up 60.6% of the study population, with no significant age differences between the two sexes (21±5 years). The risk of adjacent resorption was not linked to age but was significantly greater (P-value=0.03) for women (60%) than for men (23%). The average degree of resorption is explained jointly by sagittal position (P-value=0.0001) and transverse position (P-value=0.01), after adjustment for age and sex. On the other hand, the average degree of resorption was not linked to vertical position, nor to the shape or size of the follicular sac. CONCLUSION: This study leads to the conclusion that the risk of resorption of the lateral incisor is not linked to the buccal or palatal situation of the canine. The risk is greater when the canine is vertically above the lateral incisor root and close to the median palatine suture, suggesting a mechanical blockage by the apex of the lateral incisor.

Impact of genioplasty during puberty on the upper airways.

AIM: Mouth breathing is a functional disorder that affects craniofacial and dento-alveolar growth and also upper airway (UA) anatomy. This is apparent mainly in dimensional abnormalities of the UA caused by hypertrophy of Waldeyer's ring and excessive vertical development of the lower part, giving rise to labial incompetence that perpetuates the functional disorder. The main aim of this study was to evaluate the development of the oropharyngeal structures in young hyperdivergent patients who had undergone functional genioplasty in the context of orthodontic treatment. METHODS: This is a comparative retrospective study performed on 47 adolescents who were hyperdivergent, non-obese and exclusive or diurnal mouth breathers, treated at the Centre de soins, d'enseignement et de recherche dentaires (CSERD) in Montpellier, France. All were candidates for early genioplasty for vertical reduction, and were undergoing or at the end of treatment: 23 had been treated surgically (functional genioplasty), and 24 controls had received orthodontic treatment alone. Inter-group comparison of the changes in cephalometric measurements of the oro- and nasopharyngeal zones and maxillomandibular measurements was performed using covariance analysis (ANCOVA) to adjust for confounding factors. RESULTS: Concerning the skeletal structures: in the sagittal dimension, genioplasty led to significantly greater projection of the symphysis in the surgical group than in the control group (P<0.001). However, the sagittal position of the hyoid bone was unchanged. Similarly, in the vertical dimension, the reduction in divergence of the bony base was significantly greater in the surgical group (P<0.001), but with no change in the vertical position of the hyoid bone. Concerning the upper airways: at the level of the nasopharynx, there was a significantly greater increase in the velopharyngeal space in the surgical group (P<0.033). The same observation can be made on the level of the oropharynx, where there was a significant increase in the linguopharyngeal space in the surgical group (P<0.05), which was not the case in the control group. The change in the depth of the pharynx did not differ significantly between the two groups. CONCLUSION: Early genioplasty performed on adolescents during the growth phase helps to recalibrate the UA by encouraging spontaneous lip closure.

Successful orthodontic-surgical treatment: aiming for esthetics and function. Analysis of some clinical cases.

Adult patients who consult an orthodontist are looking for dental rehabilitation underpinned by an implicit esthetic demand, which needs to be analyzed. When the discrepancy involves more than the teeth and cannot be corrected by dentoalveolar compensation alone, there is a need, on account of the lack of growth, the periodontal setting and underlying dysfunctions, for an orthodontic-surgical solution. A clear understanding of the required future functional balance will help achieve a satisfactory esthetic target and give stable, lasting results.

Ventilatory disorders and facial growth: benefits of early genioplasty.

AIM: The purpose of this prospective study was to determine whether combined functional genioplasty and orthodontic treatment in patients with vertical mandibular growth can be beneficial not only in achieving an esthetic outcome and orthodontic stability but also for the multi-disciplinary management of oral ventilation. METHODS: Twenty-five non-obese adolescents (mean age: 14.6 ± 1.4 years) with vertical excess of the lower third requiring genioplasty received surgery following orthodontic treatment. All were predominantly mouth-breathers despite ENT treatment and rehabilitation. The functional before-after impact of genioplasty was examined in a clinical setting using polysomnography. RESULTS: Before genioplasty, 52% of the adolescents presented an upper airways resistance syndrome (UARS) with obstructive hypopnea and poor sleep quality. Three to 6 months after genioplasty, the mode of ventilation shifted from oral to nasal (p < 0.001). Lip seal was significantly restored with no contraction of the labio-mental muscles. All nighttime symptoms improved. The proportion of patients suffering from ronchopathy (pathological snoring), dry mouth and disturbed sleep dropped significantly (p = 0.08, p = 0.001, p = 0.0009, respectively). Respiratory events and sleep pattern became normal. Below, we present two clinical reports involving obstructive sleep apnea syndrome (OSAS). CONCLUSIONS: Genioplasty performed during puberty promotes spontaneous lip closure and helps restore nasal ventilation. It improves the obstructive disorder and its manifestations during sleep.

Impact of genioplasty on mandibular growth during puberty.

AIM: Genioplasty has been validated for the correction of mandibular vertical excess and is generally performed at the end of the growth period, either alone or in association with other forms of osteotomy. Our aim was to assess whether genioplasty performed at an earlier age can impact mandibular growth. METHODS: This comparative prospective study included 25 high-angle, mouth-breathing adolescents following orthodontic and ENT treatment. Subjects were divided into two groups according to their stage of puberty, either early (group 1: Tanner's stage 3, n=12) or late stage (group 2: Tanner stage 4-5, n=13). Genioplasty was performed in both groups. Cephalometric comparison was made on the overall population and for each group, before and after genioplasty (at 1, 6, 12 and 18months). RESULTS: In the immediate postoperative period, significant variation of all the cephalometric measures was observed within each group showing reduction of the vertical dimension and sagittal augmentation. Eighteen months post-surgery, only group 1 exhibited a significant increase in SNPog. Augmentation of the SNB and anterior mandibular rotation were also significantly greater in group 1. The difference in the direction of growth of the mandible before genioplasty (18months of orthodontics) and postgenioplasty (18months of postoperative monitoring) was also significant. CONCLUSION: Early genioplasty permits redirection of mandibular growth conducive to orthopedic correction of high angle Class II.

[Insertion of min-screws: with or without pre-drilling?]. / Mise en place des mini-vis: avec ou sans avant-trou?

UNLABELLED: The recent introduction of the new systems of intraosseous anchorages called mini-screw, allowing an immediate loading, has revolutioned the clinical and biomechanical approach of anchorage in orthodontics. Trans-gingival insertion by a manual screwdriver is done easily and most frequently without before-hole. The goal of this experimental study is to show that the realization of a before-hole limits the intraosseous constraints during screwing. This having short-term effects on the primary stability of the mini-screws and long-term effects on their maintenance. MATERIALS AND METHODS: two self-drilling and self-tapping mini-screws Aarhus Medicon of 1.6 and 1.3 mm diameters are screwed with a manual screwdriver, without then with a before-hole, in a plate of cortical bone fixed on a sensor measuring the forces and the couple. RESULTS: the realization of a before-hole in the cortical bone significantly decreases the maximum vertical force (FVM) at the beginning of screwing (p < 0.0001) and the maximum screwing couple (CVM) at the end of the screwing (p < 0.0001), this independently the diameter of the screw. CONCLUSION: screwing without before-hole led to the alteration of the osseous surface layer caused by micro fractures which limit the possibilities of blocking of the mini-screws.