Orthognathic surgery: a significant tool for reassessment / La chirurgie orthognathique : un outil à ne pas oublier dans la réévaluation

Introduction: More than 15 years of experience in orthodontic-surgical collaboration has allowed the authors to identify some situations in which a new perspective is needed. Although it may seem easy to refer a patient to a maxillo-facial surgeon in cases of major dysmorphoses, this can lead to yet other dilemmas: a loss of results at the end of a developmental growth stage, an adult requesting a return to treatment after a camouflage orthodontic treatment or a non-cooperative child in an interceptive and preventive treatment phase. Then, a comprehensive process of reassessment becomes compulsory. Material and Method: In the form of an editorial, this article describes various cases encountered in the authors' practice. Discussion: The aim is not to point out the imperfections of our humanity, but simply to open our eyes to diagnostic elements that are missed, whether in the initial phase or during reassessment. Conclusion: As it is far from ideal to keep offering similar therapies that lead to the same pitfalls, it is time for a shift in the paradigm.

Introduction: Plus de 15 ans de recul en collaboration orthodontico-chirurgicale ont permis aux auteurs d'identifier un certain nombre de situations dans lesquelles un regard différent est devenu opportun. S'il est aisé d'orienter un patient vers un(e) chirurgien(ne) maxillo-facial(e) en cas de dysmorphoses majeures, les orthodontistes sont régulièrement confrontés à d'autres dilemmes : une perte de résultat en fin de croissance, un adulte demandeur d'une reprise après un traitement en compensation ou encore un enfant non-coopérant en phase interceptive. Une phase de réévaluation exhaustive devient alors nécessaire. Matériel et méthode: Sous la forme d'un éditorial, cet article expose différentes situations cliniques auxquelles les auteurs ont été confrontés lors de leur pratique. Discussion: Le propos n'est pas de pointer les imperfections de notre humanité mais seulement d'ouvrir les yeux sur des éléments diagnostiques qui échappent, que ce soit en phase initiale ou en réévaluation. Conclusion: Offrir une thérapeutique identique conduisant aux mêmes écueils n'est pas acceptable : il est temps de changer de paradigme.

Effect of clear aligner type on maxillary full-arch intrusion: 3D analysis using finite element method.

BACKGROUND: Vertical maxillary excess (VME) is one of the most common reasons for seeking orthodontic treatment. Total intrusion with aligners is a promising alternative to surgery in some cases. Considering the elastic deformation of aligners, this study aimed to evaluate the possible desirable and undesirable teeth displacements during full maxillary arch intrusion using clear aligners and temporary anchorage devices (TADs). METHODS: The maxillary arch and clear aligners were modeled in SolidWorks. Four aligner brands including Leon, Duran, Duran Plus, and Essix Plus were selected based on their material properties. Anterior and posterior intrusion forces of 80 and 300 g were applied from attachments between the canines and first premolars and between the first and second molars, respectively. Vertical and anteroposterior tooth displacements were determined. RESULTS: The greatest intrusion was recorded at the buccal of the second molar, followed by the first molar. The lowest value was measured at the palatal of the molars with all aligners except Duran, which indicated minimal intrusion in the central incisor. All teeth were mesially displaced at the incisal/occlusal except incisors that moved distally. All apices showed distal movement. CONCLUSIONS: Total intrusion using clear aligners may be accompanied by other tooth movements, including buccal tipping and mesial-in rotation of the molars, retrusion of incisors, and mesial movement of other teeth.

[Application of PAR index and cephalometrics for camouflage therapy and orthodontic-orthognathic surgery in adults with skeletal Class â ¢ malocclusion].

PURPOSE: To investigate the value of PAR index combined with cephalometry in evaluating the efficacy of mild to moderate skeletal Class Ⅲ malocclusion. METHODS: Sixty-five adult patients with skeletal Class Ⅲ malocclusion were selected and divided into group C (camouflage therapy) and group S (orthodontic-orthognathic surgery)according to different treatment methods. PAR index and cephalometric values before and after treatment in each group were compared, and then the differences of PAR index and cephalometric values before and after treatment between the two groups were compared. The clinical effect was evaluated by these indexes. SPSS 25.0 software package was used for data analysis. RESULTS: In PAR index, the tooth alignment, occlusion, overjet, overbite, midline, total score and weighted total score after treatment of both groups were all significantly lower than those before treatment(P＜0.001). The differences of left and right buccal bite and total posterior bite of group S before and after treatment was significantly larger than those of group C(P＜0.001). In cephalometric measurement, the differences of SNA, NA-PA, L1-NB, U1-L1, U1-SN and L1-MP in group C before and after treatment were significantly different(P＜0.05), while those in group S before and after treatment were SNA, SNB, ANB, NP-FH, NA-PA, L1-NB, U1-L1U1-SN and L1-MP(P＜0.001). The differences of SNB, ANB and NP-FH before and after treatment in group S were significantly greater than those in group C(P＜0.001). CONCLUSIONS: Both treatments are effective for adult patients with mild to moderate skeletal Class Ⅲ malocclusion. The effect of orthodontic-orthognathic treatment is better than camouflage therapy in occlusal relationship of posterior teeth, the position of mandible relative to cranium, the mutual position of upper jaw and lower jaw relative to cranium, and the degree of mandibular convexity. PAR index combined with cephalometric measurement can effectively judge the clinical effect of adult patients with mild to moderate skeletal Class Ⅲ malocclusion, which is a good evaluation method.

Factors influencing treatment outcomes assessed by the American Board of Orthodontics Objective Grading System (ABO-OGS).

BACKGROUND: Treatment outcomes can be influenced by various factors. This study aimed to determine the association between predisposing patient- and treatment-related factors (demographic, cephalometric parameters, skeletal relationships, Discrepancy Index (DI), extractions, treatment type and duration) and treatment outcomes measures according to the American Board of Orthodontics Objective Grading System index (ABO-OGS). METHODS: Completed cases (N = 100) were included in this cross-sectional study. One calibrated examiner assessed DI, pretreatment lateral cephalometric parameters and ABO-OGS. Patient data, including sex, age, types of malocclusion, extractions, treatment type, and duration, were also collected. Intraexaminer reliability for each measurement was evaluated using the intraclass correlation coefficients. Multiple linear regression analysis, using the backward elimination method with a significance level (α) of 0.05, was used to determine which factors significantly influenced the ABO-OGS score. RESULTS: From the study, the overall mean ABO-OGS score was 11.36 points. Factors influencing the ABO-OGS score were pretreatment Wits values (p value = .000), L1-NB (°) (p value = .023) and treatment duration (p value = .019). Subjects with lower negative values of Wits and L1-NB (°) tended to have higher ABO-OGS scores. Additionally, the ABO-OGS score tended to be higher for subjects with longer treatment times. CONCLUSIONS: The majority of treated subjects had satisfactory orthodontic treatment outcomes assessed by the ABO-OGS. The pretreatment severity of skeletal discrepancies determined by the Wits parameter, the degree of retroclined lower incisors and longer treatment duration negatively impacted the treatment outcomes.

Evaluation of occlusal bite force distribution by T-Scan in orthodontic patients with different occlusal characteristics: a cross sectional-observational study.

BACKGROUND: The aim of orthodontic treatment, apart from esthetic and functional corrections, is uniform force distribution. Hence Occlusal analysis using a T scan gives scope for a precisely targeted treatment plan. The T-scan evaluation of occlusal force, time, and location of contacts from initial occlusal contact to maximum intercuspation enables the orthodontist to sequentially balance the occlusal forces on the right and left sides through specific treatment plan options. OBJECTIVE: The current study aimed to determine the force distribution in the different individuals by using a T-Scan as well as the net discrepancies of forces generated at a maximum intercuspation position in the first molar region between the left and right sides of the mouth. METHODS: This is a descriptive-correlational study that was carried out in Ras Al Khaimah College of Dental Sciences clinics and Ajman University clinics from January 2020 to September 2022 by using the convenience sampling technique. The T-scan III Novus was employed in this investigation to record multi-bite scans for several patients. T-scan was utilised to examine various malocclusions. RESULTS: The present study consisted of 158 participants. Analysis of Variance (ANOVA) showed that there is a statistically significant difference in the percentage of force between the three types of malocclusions (I, II, and III) on the right molar side (B-16 and B-46) (p < 0.05). Moreover, the overall discrepancy showed a statistically significant difference in the three types of malocclusion classifications (p < 0.05). On the other hand, there was no statistically significant difference in the percentage of force between B-26 and B-36 (p > 0.05). Post hoc analysis showed a statistically significant difference in the percentage of force between malocclusion classes I and III on the right molar, with a mean difference of 4.11190 (p < 0.05). Similarly, there was a statistically significant difference in B-46 between Malocclusion Classes I and II, 4.01806 (p < 0.05). Additionally, post hoc analysis showed a statistically significant difference between malocclusion classes I and III, with a mean difference of -4.79841 (p < 0.05) on the right molar. CONCLUSION: The T-Scan is a useful tool for assessing occlusal discrepancies and can be helpful during treatment planning and follow-up, especially for orthognathic surgery patients. A T-scan could be used in orthodontic therapy in a simple and efficient way. Also, it turned out to be a useful tool for diagnosing problems and gave us new information about how therapies work. In this study, T-Scan showed that it can measure occlusal forces in timing in an objective, accurate, and repeated manner. The current study found that T-Scan was better able to report the difference in the percentage of force on the right molar side than on the left side.

Efficacy of an innovative Herbst appliance with TADs for patients with hyperdivergent class II malocclusion: study protocol for a randomised controlled trial.

INTRODUCTION: Class II treatment with mandibular retrusion often involves the Herbst appliance due to its efficiency and low requirement of cooperation. Despite its advantages, it causes side effects concerning the occlusal plane and pogonion in terms of clockwise rotation that hinder the desired mandibular advancement for hyperdivergent patients. In this study, we will use a newly designed Herbst appliance, and a protocol that is accompanied by TADs for vertical control to avoid maxillary clockwise rotation. We hypothesise that the effect of the Herbst appliance with the vertical control approach will be beneficial for maintaining or even decreasing the skeletal divergence in hyperdivergent class II patients compared with conventional Herbst treatment. METHODS AND ANALYSIS: This study is a randomised, parallel, prospective controlled trial that will study the efficacy of Herbst with or without vertical control in children with hyperdivergent skeletal class II malocclusion. A total of 44 patients will be enrolled and randomised in a ratio of 1:1 to either Herbst treatment or Herbst treatment with vertical control. Participants will be recruited at the Shanghai Stomatological Hospital, Shanghai, China. The primary endpoint is the change in the angle indicating the occlusal plane and Sella-Nasion plane from baseline (T0) to the primary endpoint (T2) on cephalometric measurements by lateral X-ray examination. Important secondary outcomes include the root length of the anterior teeth, and the assessment score of the Visual Analogue Scale Questionnaire, etc. Safety endpoints will also be evaluated. ETHICS AND DISSEMINATION: This study has been approved by the ethics committee of the Shanghai Stomatological Hospital (Approval No. (2021) 012). Before enrolment, a qualified clinical research assistant will obtain written informed consent from both the participants and their guardians after full explanation of this study. The results will be presented at national or international conferences and published in peer-reviewed journals. TRIAL REGISTRATION NUMBER: ChiCTR2100049860, Chinese Clinical Trial Registry.

[Effect of maxillary expansion combined with orofacial myofunctional therapy on the position of the tongue of children with mouth breathing].

Objective:This study aimed to investigate the change of the position of the tongue before and after combined treatment of maxillary expansion and orofacial myofunctional therapy in children with mouth-breathing and skeletal class Ⅱmalocclusion. Methods:A total of 30 children with skeletal class Ⅱ malocclusion and unobstructed upper airway were selected. The 30 children were divided into mouth-breathing group（n=15） and nasal-breathing group（n=15） and CBCT was taken. The images were measured by Invivo5 software. The measurement results of the tongue position of the two groups were analyzed by independent samples t-test. 15 mouth-breathing children with skeletal class Ⅱ malocclusion were selected for maxillary expansion and orofacial myofunctional therapy. CBCT was taken before and after treatment, the measurements were analyzed by paired sample t test with SPSS 27.0 software package. Results:The measurement of the tongue position of the mouth-breathing and nasal-breathing groups were compared, the differences were statistically significant（P<0.05）. The measurement of the tongue position showed significant difference after the combined treatment of maxillary expansion and orofacial myofunctional therapy in children with mouth-breathing and skeletal class Ⅱmalocclusion（P<0.05）. Conclusion:Skeletal class Ⅱ malocclusion children with mouth-breathing have low tongue posture. The combined treatment of maxillary expansion and orofacial myofunctional therapy can change the position of the tongue.

Comparison of masticatory myofunctional rehabilitation combined with conventional functional appliances for the treatment of class â ¡, division 1 malocclusion. A retrospective cohort study.

OBJECTIVE: To estimate the clinical efficacy of early masticatory myofunction rehabilitation combined with conventional functional appliances for the treatment of class Ⅱ, division 1 malocclusion in orthodontic children during the growing phase. MATERIALS AND METHOD: A comparative retrospective cohort study, enrolled patients diagnosed with class Ⅱ/1 in the stage of late mixed or early permanent dentition. Patients were divided into a TBA group (Cohort 1): receiving Twin-block appliance treatment; and a MMR group (Cohort 2): receiving either early masticatory myofunction rehabilitation as adjunctive therapy combined with the same conventional functional appliances. The study variables were active (Phase 1) treatment duration, oral esthetic subjective impact score (OASIS), several cephalometric indices calculated from X-ray photographs, the maximum voltage (mV) and asymmetry index (AsI) of anterior temporalis (TA) and masseter muscles (MM) before and after treatment. Complications were also recorded. RESULTS: A total of 424 cases were enrolled. The mean treatment duration in the MMR group was 168.33 days (SD: 25.43) and 215.00 days (SD: 28.81) in the TBA group; mean difference: -46.67 days (95% CI: [-81.62, -11.71]), P<0.001. For the OASIS outcome measure, there was no statistically significant difference between the mean total scores for the MMR group (18.83±7.73) or TBA group (17.67±6.47) groups adjusted to include pre-treatment OASIS scores (P = 0.783). After treatment, sella-nasion-B point (SNB), mandibular incisor angle, maxillary base and mandibular base in both two groups were significantly increased, while AB plane angle (ANB), maxillary incisor angle, overjet and overbite were significantly decreased. The mV and AsI of TA and MM were also improved following treatment. However, no significant differences were observed between two groups. CONCLUSION: Our results confirmed that early masticatory myofunction rehabilitation in combination with conventional TBA for patients in the growing phase was significantly effective in the management of class Ⅱ/1 in orthodontic treatment, which could significantly shorten the treatment duration and had the similar improvement in the cephalometry data, OASIS scores and masticatory muscles function when comparing to conventional TBA alone.

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).

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.

The application of a fully digital approach in the treatment of skeletal class III malocclusion: a preliminary study.

BACKGROUND: Skeletal malocclusion patients have facial malformations and occlusal dysfunctions that require orthodontic-orthognathic joint treatment, while the combination treatment takes time and requires close communication between surgeons and orthodontists. Thus, improving the efficiency and effectiveness of the combination treatment is necessary, and it is still a challenge. Now, digital technology provides us with an excellent alternative. Despite the widespread use of digital technology in orthognathic surgery simulation and clear aligner orthodontic therapy, it has not been fully integrated into the combined orthognathic and orthodontic treatment process, and the components remain independent. METHODS: A fully digital approach to seamlessly integrating various parts of the combined treatment through digital technology was investigated in this study in order to achieve an efficient transition. Five patients with skeletal Class III malocclusion were enrolled, and all made fully digital treatment plans at the beginning of actual implementation, which included the design of pre-surgical orthodontic, orthognathic surgery, and post-surgical orthodontic. Then, every aspect of the clinical operation was carried out in accordance with the fully digital routine. After the entire treatment process was completed, the skeleton and dentition discrepancy between virtual planning and the actual result was evaluated. RESULTS: All participants completed the fully digital treatment process, and no complication was observed. The linear deviation of the skeletal anatomy was less than 1 mm, and the angular deviation was less than 1 degree. Except in one case in the lower dentition, the deviation of the virtual dental design from the real alignment was less than 2 mm. Furthermore, with one exception of maxillary anterior-posterior dimension, the linear deviations of the skeleton were not statistically significant. Therefore, the simulation accuracy of the fully digital approach was clinically acceptable. CONCLUSIONS: The digital treatment approach is clinically feasible and has achieved satisfactory results. The discrepancy between virtual design of the entire digital process and actual post-treatment situation was acceptable in clinic. A fully digital approach was proved effective in the treatment of skeletal Class III malocclusion, with which the efficient transition of treatment procedures was realized.

Rehabilitation of severe dentofacial deformity after early radiotherapy of retinoblastoma: a case report.

BACKGROUND: Retinoblastoma is an intraocular cancer of infancy and childhood, which has been treated with radiation therapy and chemotherapy. Radiation on growing patients can cause deterioration in maxillofacial growth and development that leads to severe skeletal discrepancies between the maxilla and mandible, and dental problems such as crossbite, openbite, and hypodontia. CASE PRESENTATION: We present the case of a 19-year-old Korean man with chewing disability and dentofacial deformities. He had undergone enucleation of the right eye and radiation therapy of the left eye due to retinoblastoma 100 days after birth. Subsequently, he received cancer therapy for the secondary nasopharyngeal cancer at the age of 11 years. He was diagnosed with severe skeletal deformity including sagittal, transverse, and vertical growth deficiency of the maxilla and midface, and with class III malocclusion, severe anterior and posterior crossbite, posterior openbite, multiple missing upper incisors, right premolars, and second molars, and impaction of the lower right second molars. To restore impaired functions and esthetics of the jaw and dentition, the orthodontic treatment combined with two jaw surgery was performed. At the end of surgical orthodontics, dental implants were placed for prosthetic treatment of missing teeth. Additional plastic surgery for zygoma elevation was done with calvarial bone graft followed by fat graft. Facial esthetics and occlusal functions of patient were favorably enhanced with the improvement of skeletal discrepancy and the rehabilitation of maxillary dentition by prosthetic work. At the 2-year follow-up, the skeletal and dental relationships and implant prosthetics were well maintained. CONCLUSION: In an adult patient with dentofacial deformities caused by early cancer therapy in the head and neck area, interdisciplinary interventions including additional plastic surgery of zygoma depression and prosthetic work of missing teeth as well as surgical-orthodontic treatment could establish favorable facial esthetics and oral rehabilitation.

An adult case of unilateral posterior crossbite caused by maxillary transverse deficiency treated with miniscrew-assisted rapid palatal expansion.

This report describes the successful treatment of an adult case of unilateral posterior crossbite caused by maxillary transverse deficiency with miniscrew-assisted rapid palatal expansion (MARPE). A female patient aged 35.5 years presented with masticatory disturbance, facial asymmetry, and unilateral posterior crossbite. She was diagnosed with unilateral posterior crossbite with a skeletal Class III jaw-base relationship and high mandibular plane angle. Her maxillary right and mandibular bilateral second premolars were congenitally absent, and the maxillary left second premolar was impacted. After the improvement of the posterior crossbite with MARPE, 0.018″ slot lingual brackets were placed on the maxillary and mandibular dentition. The total active treatment period was 22 months, and acceptable occlusion with a functional Class I relationship was achieved. Pretreatment and posttreatment cone-beam computed tomography images showed the disarticulation of the midpalatal suture after MARPE, and changes in the dental and nasomaxillary structures, nasal cavity, and pharyngeal airway. The case results demonstrate that MARPE produces greater skeletal expansion with minimal buccal tipping of the molars. MARPE may be effective for the treatment of maxillary transverse deficiency in adult patients.

Evaluation of occlusal function during orthognathic therapy : A prospective clinical trial using a digital registration method.

OBJECTIVES: Reduced occlusal function is a main characteristic of orthognathic patients. The present study aimed to investigate the extent of therapy-induced functional improvements in occlusal function using a digital diagnostic method. METHODS: This prospective clinical study included 41 orthognathic patients (24 women and 17 men, median age 27.26 ± 8.2 years) and 10 control patients (5 women and 5 men, median age 29.8 ± 13.5 years) with neutral skeletal and dental configurations. The patients were divided into classes I, II and III based on their cephalometry. Digital occlusal registrations in habitual occlusion in an upright sitting position were taken before (T1) and after (T2) therapy using the T­Scan Novus (Tekscan, South Boston, MA, USA) application. RESULTS: Class II and III patients showed a significantly less efficient occlusal pattern than the untreated controls regarding total antagonism (p < 0.001), time of occlusion (p = 0.004), occlusal asymmetry (p = 0.001), anterior antagonism (p < 0.001) and posterior antagonism (p < 0.001). After therapy, the occlusal pattern increased in both therapy groups, where class III patients became indistinguishable from the controls, and class II patients differed only in posterior antagonism (p = 0.035). CONCLUSIONS: The digital occlusal registration method proved to be a useful diagnostic tool and provided new insights into therapeutic effects in orthognathic patients. By precisely adjusting the occlusal function, masticatory performance improved significantly. CLINICAL RELEVANCE: Severe malocclusion leads to a significantly lower masticatory performance for patients, which can be improved by orthognathic therapy and captured by digital occlusal registration.

The effect of orthodontic treatment on facial attractiveness: a systematic review and meta-analysis.

BACKGROUND: Facial and smile attractiveness are significant motivating factor for patients to seek orthodontic treatment. Although there is a general belief that orthodontic treatment improves facial appearance, this has yet not been systematically evaluated. OBJECTIVE: The objective of this study was to assess the current evidence on the effect of orthodontic treatment on facial attractiveness. SEARCH METHODS: Systematic and unrestricted search of nine databases were performed up to January 2022. SELECTION CRITERIA: Studies evaluating facial attractiveness before and after orthodontic treatment. DATA COLLECTION AND ANALYSIS: Extracted data included study design and setting, sample size and demographics, malocclusion type, treatment modality, and method for outcome assessment. Risk of bias was assessed with the ROBINS-I tool for non-randomized studies and with RoB-2 for randomized controlled trials (RCTs). Random-effects meta-analyses of mean differences and their 95% confidence intervals (CIs) were performed. RESULTS: Twenty studies were included in data synthesis; three randomized controlled clinical trials and 17 non-randomized clinical studies of retrospective or prospective design. One of the RCTs was found to have low risk of bias, one presented some concerns and the third showed a high risk of bias. All non-randomized studies showed either unclear or high risk of bias. Data syntheses showed that orthodontic treatment improved facial attractiveness ratings by 9% when compared with untreated controls (MD: 9.05/95% CI: 4.71; 13.39). A combination of orthodontics and orthognathic surgery also showed a positive effect of 5.5% (MD: 5.51/95% CI: 1.55; 9.47) when compared with orthodontic treatment alone. There was no difference in effect between extraction and non-extraction treatments (MD: -0.89/ 95% CI: -8.72; 6.94) or between different types of Class II correctors (MD: 2.21/95% CI: -16.51; 20.93). LIMITATIONS: With the exception of two RCTs, included studies were of unclear or low quality. CONCLUSIONS: Orthodontic treatment has a clinically weak effect on facial attractiveness when compared to no treatment. The same is true when a combined orthodontic/surgical treatment is compared to orthodontics alone. REGISTRATION: PROSPERO #: CRD42020169904.

Do we get better outcomes from early treatment of Class III discrepancies?

Early orthodontic treatment in the mixed dentition aims to simplify definitive treatment in the permanent dentition. In Class III cases, this can be an effective strategy for the management of a local anterior crossbite, using either a removable or simple fixed appliance. For more significant Class III malocclusions, the decision to intervene early is a more difficult one. Traditionally, orthodontists in the UK have been reluctant to embark on early treatment in the presence of a skeletal Class III relationship but there is now some evidence that in selected cases, the use of protraction headgear can be a successful method of avoiding the need for later surgery. Although growth prediction in Class III cases is notoriously difficult, in the presence of maxillary retrognathia, the general dental practitioner should consider early referral of Class III cases to a specialist orthodontist.

Exploring the mylohyoid area as a reference for three-dimensional digital mandibular superimposition.

INTRODUCTION: the quantification of tooth movements should be obtained at different specific times and compared at different stages for every orthodontic treatment. These movements are generally measured on teleradiographs or casts. The use of Cone Beam Computed tomography (CBCT) for maxillary superimposition is clearly established in the literature, but not well defined for mandibular superimposition. This study aims to explore and evaluate the accuracy of the mylo-hyoid area as a reference for mandibular Digital Dental Cast (DDC) three-dimensional (3D) superimposition. MATERIALS AND METHODS: the study compared mandibular 3D overlays with profile teleradiographs in 30 patients followed at Nice Saint Roch University Hospital. The molar and incisor coordinates on the 3D superimposition based on the mylo-hyoid area were compared to the ones on the 2D lateral cephalogram. Differences between the two methods of superimposition were assessed using paired t-tests. RESULTS: No statistically significant difference was observed between the lateral cephalogram-based and mandibular DDC superimposition methods in 3D sagittal and vertical displacements of the lower first molars and central incisors. CONCLUSION: The study showed the mylo-hyoid area to be an accurate superimposition landmark for the 3D evaluation of mandibular orthodontic tooth displacement. This method is also applicable for patients with conventional orthodontic treatment records. Other studies should be conducted on larger populations, subgroups (malocclusions, therapeutics) and on the use of an intra-oral camera.

Craniofacial treatment protocol for a pediatric patient with obstructive sleep apnea and skeletal Class III malocclusion: A 13-year follow-up.

This report aimed to describe the long-term effects of craniofacial growth modification treatment on sleep and breathing functions in a 7-year-old girl diagnosed with skeletal Class III malocclusion and sleep-disordered breathing. Based on the flowchart of orthodontic intervention protocol that we proposed for phenotype-based patient selection and skeletal target-based treatment selection for pediatric patients with sleep-disordered breathing, a 2-phase treatment targeting the nasomaxillary complex was performed. Posttreatment 3-dimensional changes in the skeletal structure and upper airway were evaluated in association with functional assessment using a validated pediatric sleep questionnaire and home sleep test. Esthetic improvement and obstructive sleep apnea cure were achieved without skeletal surgery. The 2-year retention records showed stable occlusion and improved facial profile with normal breathing and sleep.

Ideal treatment timing of orthodontic anomalies-a German clinical S3 practice guideline.

PURPOSE: Ideal treatment timing in orthodontics is controversially discussed depending on the type and extent of the dysgnathia and malocclusion present, especially with regard to efficiency, patient burden and treatment efforts of early compared to regular or late treatment. This German clinical practice guideline aims to clarify, at which time points an orthodontic anomaly can be effectively treated and how treatment efficiency differs depending on treatment timing. METHODS: A systematic literature search was performed in various guideline databases and databases PROSPERO, MEDLINE (PubMed), Cochrane Library, Web of Science, ClinicalTrials.gov and the International Clinical Trials Registry Platform according to a predefined PICO (Population, Intervention, Comparison and Outcomes with added qualitative search terms) search algorithm and strategy. Appraisal of scientific evidence of the individual studies checked for eligibility was carried out according to SIGN (Scottish Intercollegiate Guidelines Network), AMSTAR II (Assessing the Methodological Quality of Systemic Reviews), and AXIS (Appraisal Tool to Assess the Quality of Cross-sectional Studies) tools. Only controlled studies with a high, acceptable or moderate quality (and thus an acceptable risk of bias) were considered. RESULTS: A total of 309 studies of over 11,000 sources screened were identified to be eligible for inclusion and critically appraised for study quality and risk-of-bias. No relevant guidelines relating to the aims of the present guideline were found. Elected delegates of in total 21 German scientific societies and organizations agreed upon a total of 19 evidence-based statements and recommendations based on a nominal consensus process. CONCLUSIONS: Although most malocclusions can be effectively treated both in the early, late mixed, and permanent dentition, evidence suggests that therapy of a pronounced skeletal or dental class II anomaly can be started early to reduce the risk of dental anterior tooth trauma, whereas in a moderate class II anomaly, therapy can preferably be carried out before or during the pubertal growth peak. Therapy of a skeletal or dental class III anomaly should be started early, as this also reduces the need for later surgery to correct the anomaly. The treatment of a pronounced skeletal or dental transverse anomaly should be started early in the upper jaw in order to utilize the high adaptivity of the maxillary structures in young patients.

Evaluation of the effectiveness of modified aligner appliance with nickel-titanium springs in treatment of mild crowding of lower incisors: A randomized controlled clinical trial.

BACKGROUND: This study aimed to evaluate the effectiveness of modified aligner appliances with nickel-titanium springs (MAAs) in treating mild mandibular crowding and assess the overall alignment treatment duration, alignment improvement percentage, and mandibular incisor proclination. METHODS: This two-armed, parallel-group randomized controlled trial included 36 patients (7 men, 29 women) with mild mandibular incisor crowding according to Little's Irregularity Index. Patients were randomly assigned to two groups: the MAA group (mean age = 22.56 ± 3.50 years) and the conventional fixed bracket group (control group; mean age = 20.89 ± 2.90 years). The duration of alignment treatment of the lower anterior teeth was calculated. The progress of alignment was evaluated every 2 weeks on the study casts, which were taken at fixed intervals: pretreatment (T0) and 2 (T1), 4 (T2), 6 (T3), and 8 (T4) weeks after beginning the treatment. Change of mandibular incisor proclination was evaluated by measuring and comparing pretreatment and postalignment lateral cephalograms. RESULTS: No statistically significant difference was detected between the two groups in terms of alignment treatment duration (P = 0.097), whereas a significant difference was observed in the alignment improvement percentage at T1 (P = 0.000), T2 (P = 0.001), and T3 (P = 0.022). In addition, the MAA group had a lower change of mandibular incisor proclination than the control group (P = 0.000). CONCLUSIONS: The clinical application of MAAs may be effective in lower incisor decrowding, with a reduction in lower incisor inclination compared with conventional fixed brackets. This trial was registered at ClinicalTrials.gov (identifier: NCT04988373).