The goniomaxillar length/goniomandibular length ratio in normal newborn infants: A clinical tool for defining chin position abnormalities.

Retrognathia (recessed chin) and prognathism (prominent chin) often present as signs of an underlying condition. Accurate clinical definitions are important. Yet their definitions were according to "clinical impression", or to seldom used X-ray criteria. We propose a statistical and anthropometric definition of retrognathia and prognathism based upon the ratio between the goniomaxillar length (distance between the gonion at the mandible angle and the subnasale and the goniomandibular length (distance between the mandible angle and the most anterior point of the bony chin). We assumed that an increase in the ratio indicates retrognathia and a decrease reflects prognathism. We conducted a prospective, observational, anthropometric study in 204 consecutive healthy term infants. Measurements took place on the second day of life, using sliding calipers. Mean ± SD of goniomandibular length (5.1 ± 0.3 cm), goniomaxillar length (5.4 ± 0.3 cm), were calculated. All measurements correlated significantly with gestational age, and with infant birthweight. The mean ± SD goniomaxillar length/goniomandibular length ratio was 1.06 ± 0.05. We defined a normal ratio as being within 2 SD of the mean, that is, between 0.96 and and 1.16. This ratio correlated with neither gestational age nor with birthweight. We conclude that the goniomaxillar length/goniomandibular length ratio can be calculated whenever retro - or prognathism is suspected. A ratio outside of the 95% confidence interval should help in making this diagnosis. An increase in this ratio beyond 2 SD above the mean (1.16) could be interpreted as retrognathia and a decrease beyond 2 SD below the mean (0.96) as prognathism.

A Morphological Classification Scheme for the Mandibular Hypoplasia in Treacher Collins Syndrome.

BACKGROUND: Mandibular hypoplasia is a hallmark of Treacher Collins syndrome (TCS), and its severity accounts for significant functional morbidity. The purpose of this study is to develop a mandibular classification scheme. METHODS: A classification scheme was designed based on three-dimensional computed tomography (3D-CT) scans to assess 3 characteristic features: degree of condylar hypoplasia, mandibular plane angle (condylion-gonion-menton), and degree of retrognathia (sella-nasion-B point angle). Each category was graded from I to IV and a composite mandible classification was determined by the median value among the 3 component grades. RESULTS: Twenty patients with TCS, aged 1 month to 20 years, with at least one 3D-CT prior to mandibular surgery were studied. Overall, 33 3D-CTs were evaluated and ordered from least to most severe phenotype with 10 (30%) Grade 1 (least severe), 14 (42%) Grade 2, 7 (21%) Grade 3, and 2 (7%) Grade 4 (most severe). Seven patients had at least 2 longitudinal scans encompassing an average 5.7 (range 5-11) years of growth. Despite increasing age, mandibular classification (both components and composite) remained stable in those patients over time (P = 0.2182). CONCLUSION: The authors present a classification scheme for the TCS mandible based on degree of condylar hypoplasia, mandibular plane angle (Co-Go-Me angle), and retrognathia (SNB angle). While there is a natural progression of the mandibular morphology with age, patients followed longitudinally demonstrate consistency in their classification. Further work is needed to determine the classification scheme's validity, generalizability, and overall utility.

Split-Overlapping Genioplasty: Surgical Technique, Morphological and Radiological Long-Term Outcomes.

BACKGROUND: The overlapping bone flap genioplasty, described by Tessier, was developed to treat major retrognathia or long and retruded chins. For 15 years, we have used a modified version of this technique to avoid its drawbacks. The aim of this article is to describe our modification and evaluate the long-term morphologic and radiologic outcomes. PATIENTS AND METHOD: The authors included every split-overlapping genioplasty performed in our department between 2004 and 2014. Demographics, surgical data, and complications were recorded. Radiologic bone resorption was evaluated comparing preoperative, day-1 postoperative, and year-1 postoperative cephalometric x-rays. Morphologic outcomes were evaluated on standardized pre- and postoperative views using an analogic Likert scale. SURGICAL TECHNIQUE: The main modification of the procedure consists in separating the posterior cortex of the transplant using a reciprocating saw. After overlapping the reduced transplant onto the mandible, the posterior cortex is used as an apposition graft to soften the labiomental crease. RESULTS: Forty-seven patients were analyzed during this period. In 44 patients, the procedure was combined with mandibular and/or maxillary osteotomy. The average reduction of symphysis height was 5 mm, and the average pogonion advancement was 4.3 mm. After 1 year, we recorded 7% average bone resorption. No major complications (nerve injury, hematoma, among others) were reported. Morphologic outcomes were deemed satisfactory or very satisfactory in the vast majority of cases. CONCLUSION: Split-overlapping genioplasty is a safe and reliable procedure with stable, long-lasting outcomes. This versatile technique is particularly useful for the correction of a massive symphysis or high and retruded chins.

Craniofacial characteristics of children with mild hypodontia.

INTRODUCTION: The aim of our study was to evaluate the craniofacial characteristics of children with mild hypodontia using conventional and principal component (PC) analysis. METHODS: We used radiographic images of 124 children (8-12 years old) with up to 4 missing teeth (55 boys, 69 girls) and of 676 reference children (365 boys, 311 girls) from the Rotterdam Generation R Study and the Nijmegen Growth Study in The Netherlands. Fifteen cephalometric measurements of children with hypodontia were compared with those of the reference children. Moreover, cephalometric parameters were combined into standardized PC scores using PC analysis, and the components were compared between the 2 groups. RESULTS: PC analysis showed common dental characteristics for all types of hypodontia: a significant increase of the interincisal angle, and decreases of the maxillary and mandibular incisor angles. Other findings were consistent when both methods were applied: (1) anterior hypodontia was significantly associated with the high-angle (hyperdivergent) craniofacial pattern, (2) the tendency toward a Class III malocclusion was identified in maxillary hypodontia, and (3) we observed a significant reduction of lower posterior facial height in children with posterior and mandibular hypodontia. CONCLUSIONS: Our findings suggest that children with mild hypodontia have distinctive skeletal and dental features.

[Relationship between the obstructive character of the tonsils and the sagittal cephalometric measurements]. / Relations entre le caractère obstructif des amygdales palatines et les mensurations céphalométriques du sens sagittal.

INTRODUCTION: The role of obstructive tonsils in the sagittal dimension of the skeleton-dental abnormalities is widely discussed in the literature but remains controversial. Data on the probable relationship between obstructive tonsils and the presence of these abnormalities were subjective. The objective of this study was to quantify the relationship between the obstructive character of the tonsils and the sagittal cephalometric measurements. MATERIALS AND METHODS: A cross-sectional study was performed in children aged between 6 to 12 years divided into 2 groups (A and B) according to the obstructive character of the tonsils. Cephalometric measurements were recorded on each child. Data were analyzed using SPSS 20.0 for Windows. At Student test was used to compare quantitative variables according to the obstructive character of the tonsils. Significance was set at p = 0.05. RESULTS: Subjects with obstructive tonsils (group B) are significantly more trend to have a convex facial profile and a skeletal class II with more mandibular retrusion and retroclined incisor compared with subjects without obstructive tonsils (group A). CONCLUSION: Early evaluation of children with obstructive tonsils can prevent sagittal dimension of the squeleto-dental abnormalities caused by upper airway obstruction. Thus late and more aggressive treatments which are not always as efficient as when they were performed during childhood will be avoided.

Premolar transplantation in a patient with solitary median maxillary central incisor syndrome.

This case report describes the orthodontic treatment of an 11-year-old girl with solitary median maxillary central incisor syndrome, a presumed microform of holoprosencephaly. Because both second premolars were missing in the maxilla, deciduous molar extraction and orthodontic space opening were performed, moving the solitary median maxillary central incisor electively off-center. A mandibular second premolar was transplanted to replace the missing incisor. The resulting spaces could be orthodontically closed in both arches. Prosthodontic reshaping of the transplanted tooth after debonding completed the dental treatment.

Soft-tissue profile growth in patients with repaired complete unilateral cleft lip and palate: A cephalometric comparison with normal controls at ages 7, 11, and 18 years.

INTRODUCTION: In this retrospective longitudinal study, we aimed to study differences in the soft-tissue profiles in growing children with clefts in comparison with controls through the period of facial growth from 7 to 18 years. METHODS: Lateral cephalometric measurements made at 7 years (T1), 11.1 years (T2), and 17.9 years (T3) of age of 70 white children (35 boys, 35 girls) with complete unilateral cleft lip and palate (UCLP) who received primary lip and palate repair surgeries at The Hospital for Sick Children, Toronto, were compared with those of a control group of similar ages, sexes, and racial backgrounds, and having skeletal Class I facial growth, selected from the Burlington Growth Study. None of the included subjects had received any surgeries other than the primary lip and palate repairs, and none had undergone nasal septum surgery or nasal molding during infancy. Between-group comparisons were made at each time point using generalized linear models adjusted for age and sex effects. Longitudinal comparisons across all time points were conducted using the mixed model approach, adjusting for these effects and their interactions with time. RESULTS: Bimaxillary retrognathism, progressive maxillary retrognathism, and increasing lower anterior face height with downward and backward growth rotation of the mandible in the UCLP group were seen. Unlike the hard-tissue face height ratio, their soft-tissue face height ratio was not affected. The upper lips in the UCLP group were shorter by 1.81 mm at T2 (P <0.001) and by 1.16 mm at T3 (P = 0.018), whereas their lower lips were 2.21 mm longer at T3 (P = 0.003). A reduced upper lip to lower lip length ratio at T2 and T3 (P <0.001) resulted. Their upper lips were relatively retruded by 1.44 mm at T1, 1.66 mm at T2, and 1.86 mm at T3 (all, P <0.001), and their lower lips were relatively protruded by 1.07 mm at T1 (P = 0.003), 1.40 mm at T2 (P <0.001), and 1.62 mm at T3 (P <0.001). Nose depths in the UCLP group were shallower by at least 1 mm from T1 to T3, and columellar length was shorter by almost 2 mm (all, P <0.001). Their columellae and nose tips rotated downward with growth, with the most significant rotations experienced from T2 to T3, and progressive reductions in their soft-tissue profile convexity were seen from T1 to T3 (P <0.001). CONCLUSIONS: Key attributes of the imbalance in the soft-tissue profile in children with repaired UCLP were identified in the lip and nose regions. Although many profile differences were visible as early as 7 years of age, they became more apparent by 11 years of age and increased in severity thereafter. The short upper lip combined with a long lower lip resulted in the characteristic lip length imbalance, whereas the progressively retruding upper lip and protruding lower lip led to developing a step relationship in the sagittal lip profile during the adolescent growth period. Their columellae and nose tips rotated downward during this time.

Functional therapy and adenotonsillectomy clinical trial for class II malocclusion (FACT-II): protocol for a randomised controlled trial.

INTRODUCTION: Class II malocclusion with mandibular retrognathia is a common complication of paediatric obstructive sleep apnoea (OSA), often accompanied by transverse maxillary deficiency. In early orthodontic treatment, a twin block (TB) is a regular functional appliance for correcting this malocclusion. For paediatric OSA, the most common risk factor is adenotonsillar hypertrophy (AHT). Untreated AHT may lead to the persistence and worsening of obstructive sleep-disordered breathing traits, including habitual mouth breathing. Additionally, the clockwise mandibular rotation associated with AHT-induced pharyngeal crowding can undermine the effectiveness and stability of TB treatment. Adenotonsillectomy (T&A) is currently the first-line treatment for paediatric OSA. This proposed trial will investigate the impact of T&A surgery timing on the efficacy and stability of TB functional treatment in children with class II mandibular retrognathia and ATH. METHODS AND ANALYSIS: This will be a single-centre, parallel-group, superiority randomised controlled trial with participants randomised to intervention (T&A followed by TB treatment) or control arms (TB treatment followed by T&A) in a 1:1 ratio. A total of 40 patients aged 8-14 years, diagnosed with class II mandibular retrognathia and co-existing ATH-induced OSA, and indicated for both T&A surgery and TB treatment, will be recruited at the School and Hospital of Stomatology, Wuhan University. The primary outcomes will be the changes in the apnoea-hypopnoea index and the point A-nasion-point B angle from baseline to postorthodontic treatment between the two groups. Secondary outcomes will include other dental, skeletal, upper airway and soft tissue changes, as well as subjective sleep-related and oral-related quality of life. Outcome changes within each group and between groups will be analysed. ETHICS AND DISSEMINATION: This study is approved by the Ethics Committee of the School and Hospital of Stomatology, Wuhan University (no. 2022-D07). The research findings will be faithfully disseminated through scientific conferences or published articles. TRIAL REGISTRATION NUMBER: ChiCTR2200061703 (https://www.chictr.org.cn).

Effects of twin block appliance on obstructive sleep apnea in children: a preliminary study.

BACKGROUND: Oral appliances are increasingly advocated as a treatment option for obstructive sleep apnea (OSA). However, it is not clear how the different designs influence treatment efficacy in children. The aim of this study was to investigate the effects of twin block (TB) appliance on children with OSA and mandibular retrognathia. METHODS: A total of 46 children (31 males, 15 females, aged 9.7 ± 1.5 years, BMI: 18.1 ± 1.04 kg/m(2)) diagnosed with mandibular retrognathia and OSA by polysomnography (PSG) and with no obesity or adenotonsillar hypertrophy were recruited for the study. Patients in the treatment group were instructed to wear the twin block oral appliance full time for an average of 10.8 months. The efficacy of treatment was determined by monitoring the PSG and cephalometric changes before and after appliance removal. Data were analyzed using paired t test. RESULTS: Results showed an improvement in patient's facial profile after treatment with the TB appliance. The average AHI index decreased from 14.08 ± 4.25 to 3.39 ± 1.86 (p < 0.01), and the lowest SaO2 increased from 77.78 ± 3.38 to 93.63 ± 2.66 (p < 0.01). Cephalometric measurements showed a significant increase in the superior posterior airway space, middle airway space, SNB angle and facial convexity which indicate an enhancement in mandibular growth, and reduction in the soft palate length. CONCLUSIONS: This preliminary study suggests that twin block appliance may improve the patient's facial profile and OSA symptoms in a group of carefully selected children presented with both OSA and mandibular retrognathia symptoms.

Sleep-disordered breathing: choosing the right cephalometric analysis.

PURPOSE: Cephalometry can be helpful for choosing the optimal treatment of sleep apnea. The presence or absence of maxillomandibular retrusion can contribute to the choice of treatment with an oral appliance or a skeleton-based or soft tissue surgery. To measure the position of the maxillomandibular complex, the analysis of Tweed has been cited most often. It uses dental landmarks. The analysis of Delaire relies on deeper skeletal points. The present study compared these 2 analyses for the diagnosis of maxillomandibular retrusion in a context of sleep-disordered breathing by determining the correlation between retrusion and the apnea-hypopnea index (AHI) for both methods. MATERIALS AND METHODS: A retrospective cohort study was conducted in a tertiary care university hospital. The population consisted of patients diagnosed with sleep-disordered breathing for whom polysomnographic and cephalometric data were available. Tweed and Delaire cephalometric analyses were performed for each case. The main outcome was the correlation between the degree of maxillomandibular retrusion and the AHI, as determined by Pearson coefficients. RESULTS: A total of 243 patients (42 females and 201 males) were included. For maxillary retrusion, the correlation coefficient with the AHI was -0.109 (P = .089) for Tweed and -0.160 (P = .012) for Delaire. For mandibular retrusion, the coefficient was -0.090 (P = .16) for Tweed and -0.201 (P = .002) for Delaire. Statistical significance was found only for the analysis of Delaire. CONCLUSION: The correlation between maxillomandibular retrusion and the AHI was better using the analysis of Delaire. If cephalometry is to be included in the workup of sleep-disordered breathing, the analysis of Delaire might be preferable.

The efficacy of oral appliances in the treatment of severe obstructive sleep apnea.

OBJECTIVES: The purpose of this study is to evaluate the efficacy of oral appliance (OA) treatment for subjects with severe obstructive sleep apnea (OSA) and to determine the dental parameters associated with treatment outcomes. STUDY DESIGN: This study uses a prospective longitudinal design. METHODS: Consecutive Chinese subjects with severe OSA who refused continuous positive airway pressure treatment were recruited. Their dental measurements were taken from lateral cephalometric radiographs. Polysomnograms with OA were repeated at 3 months and 1 year. Blood pressure was taken in the morning after sleep studies. RESULTS: Thirty-four subjects were evaluated at 3 months and 1 year according to the principle of intention-to-treat analysis. OA reduced AHI significantly in subjects with favorable responses, from 49.3 (37.4-67) to 12.5 (6.1-15.7), p < 0.001 at 3 months and from 47.5 (41.1-72.9) to 13.1 (6.0-14.0), p < 0.001 at 1 year. These OSA subjects had an increased overjet at baseline compared to those with unfavorable responses (p ≤ 0.05). Systolic blood pressure was significantly reduced in those hypertensive OSA subjects after 3 months and 1 year of treatment. CONCLUSIONS: OA reduces the severity of sleep apnea, and the effect is maintained at 1 year in subjects with retrognathism. OA appears to reduce systolic blood pressure in hypertensive OSA subjects at 3 months and 1 year.

Freeman-Sheldon (whistling face) syndrome with hyperpyrexia in the newborn: case report.

Freeman Sheldon syndrome (FSS) is a rare, multiple congenital contracture syndrome that is relatively well-known, since affected children have a striking appearance. This entity was historically referred to as the "whistling-face syndrome". Malignant hyperthermia and hyperpyrexia have been documented in FSS after general anesthesia related to the neuropathy. We report a male neonate with FSS and hyperpyrexia without anesthesia. To our knowledge, our patient is the first in the literature with hyperpyrexia in the newborn period without anesthesia.

Robin sequence: clearing nosologic confusion.

OBJECTIVE: To gather evidence surrounding the confusion in the classification of Robin sequence and inform those who have the power to make the changes in defining this symptom complex. METHOD: A questionnaire was sent to all participating cleft palate teams (N=204) of the American Cleft Palate-Craniofacial Association. The questionnaire identified the precise, different characteristics for diagnosing Robin sequence and evaluated whether the difference between a retrognathia and micrognathia influenced the diagnosis process. We subsequently also investigated whether the cleft type (i.e., U-shaped versus V-shaped) had any influence in the decision-making process. A PubMed literature review of the 50 most recent manuscripts about Robin sequence was evaluated also. RESULTS: Seventy-three questionnaires were received. This 35% response rate revealed 14 different definitions of Robin sequence. A PubMed literature review of 50 consecutive manuscripts revealed 15 different descriptions. CONCLUSION: This study confirms that nosologic confusion is widespread with regard to defining Robin sequence. This has implications for evaluating Robin sequence, giving advice about the prognosis and genetic counseling, and refining treatment options.

European Board of Orthodontics case report: severe skeletal discrepancy.

The 10.3 year-old patient presented a sagittal skeletal and dental Class II division I malocclusion with a severe overjet in the mixed dentition. The convex profile aesthetically improved with the mandibular advancement (positive Frankel manoeuvre). No signs or symptoms of TMJ disorders were present. Oral mucosa and gingiva conditions were good notwithstanding a scanty oral hygiene. The treatment plan included: a) Bass appliance to improve the retruded profile and, partially, OVJ; b) upper and lower arch fixed appliance for alignment, levelling and correction of the malocclusion c) posttreatment retention.

A Triad of Temporomandibular Joint Ankylosis, Mandibular Retrognathia and Severe Obstructive Sleep Apnoea: Case report.

The surgical management of paediatric patients with temporomandibular joint (TMJ) ankylosis, mandibular retrognathia and obstructive sleep apnoea (OSA) is challenging. We report a nine-year-old boy who presented to the Department of Oral Health, Sultan Qaboos University Hospital, Muscat, Oman, in 2016 with complaints of limited mouth opening, loud snoring and excessive daytime sleepiness. He was diagnosed with TMJ ankylosis, mandibular retrognathia and severe OSA. The patient initially underwent mandibular distraction and, subsequently, release of the TMJ ankylosis and rib graft reconstruction. The overall patient outcome was successful, with improvement in OSA-related symptoms, good facial symmetry and adequate mouth opening.

Evaluation and management of upper airway disorders in children.

Upper airway disorders in children may be divided into those that are congenital in origin and those that are acquired. The presentation and management of these disorders is significantly influenced both by the anatomic location of the pathology, which is usually obstructive in nature, and by the severity of the obstruction. This discussion provides an overview of the presentation, diagnosis, management, and potential complications of the most commonly seen upper airway disorders. These disorders are presented within an anatomic framework, progressing from proximal at the nares to distal at the carina.

Can anatomical and functional features in the upper airways predict sleep apnea? A population-based study in females.

CONCLUSION: The importance of clinical findings in the nose and throat, including fiberoptic endoscopy during the Muller maneuver, in predicting sleep apnea is greater in normal-weight than in overweight women. OBJECTIVES: The aim of this study was to identify clinical features that could predict sleep apnea in women. METHOD: From 6817 women who previously answered a questionnaire concerning snoring habits, 230 women who reported habitual snoring and 170 women from the whole cohort went through a full-night polysomnography. A nose and throat examination including fiber endoscopic evaluation of the upper airways during the Muller maneuver was performed in a random selection of 132 women aged 20-70 years. RESULTS: Sleep apnea was defined as an apnea-hypopnea index of > or = 10. The influence of clinical features on the prevalence of sleep apnea varied between normal-weight and overweight women. A low soft palate, retrognathia, the uvula touching the posterior pharyngeal wall in the supine position, and a 75% or more collapse at the soft palate during the Muller maneuver were all significant predictors of sleep apnea in women with a body mass index (BMI) < 25 kg/m2 but not in overweight women.

Assessment of skeletal and dental pattern of Class II division 1 malocclusion with relevance to clinical practice.

Class II division 1 malocclusion represents the most common skeletal discrepancy which orthodontists see in daily practice. The understanding of the morphology is a key element in planning dentofacial orthopedic treatment for this type of malocclusion. The purpose of the present study was to examine prepubertal children with Class II division 1 malocclusion and to evaluate maxillary and mandibular skeletal positions in comparison with normal growth standards by means of cephalometric measurements used by clinical practitioners. For the study casts and cephalograms of 86 consecutive patients with Class II division 1 malocclusion were used. The Class II division 1 malocclusion demonstrates broad variation in its skeletal and dental morphology. The retrognathic mandible (60%), maxillary prognathism (55.8%) and reduce vertical skeletal jaw relationship is the most common characteristic of Class II division 1 malocclusion. The optimal correction of the anteroposterior and vertical dental and skeletal discrepancies could be designed on the base of individual diagnosis for every Class II division 1 patient.

Occlusal stability after Herbst treatment of patients with retrognathic and prognathic facial types : A pilot study.

OBJECTIVES: The purpose of this study was to assess and compare occlusal changes induced by Herbst treatment and the stability of these changes in patients with retrognathic and prognathic facial types. PATIENTS AND METHODS: The sample comprised 11 retrognathic (SNA ≤76°, SNB ≤72°, ML/NSL ≥36°) and 10 prognathic (SNA ≥83°, SNB ≥80°, ML/NSL ≤32°) patients with Class II molar relationships of ≥0.5 cusp widths bilaterally or ≥1.0 cusp width unilaterally. Both groups involved similar distributions of skeletal maturity before treatment. Study parameters were assessed on casts reflecting the situations before treatment (T0), after Herbst treatment (T1), after multibracket treatment immediately following Herbst treatment (T2), and after a mean of 31.1 months of retention (T3). RESULTS: Sagittal molar relationships improved by 0.8 cusp widths in the retrognathic and by 0.7 cusp widths in the prognathic group during active treatment (T0-T2). Insignificant changes of ≤0,2 cusp widths were seen in both groups during retention (T2-T3). Overjet decreased by 8.6 mm in the retrognathic and by 5.5 mm in the prognathic group during T0-T2, and both groups showed clinically irrelevant amounts of relapse by 0.7 mm during T2-T3. Overbite improved by 1.2 mm in the retrognathic and by 2.5 mm in the prognathic group during T0-T2, reaching mean values of 1.0 mm or 1.4 mm by T2, which was followed by 0.2 mm or 1.1 mm of relapse during T2-T3. CONCLUSION: Treatment with a Herbst appliance seems to offer stable correction of the sagittal occlusal relationships in Class II patients with retrognathic or prognathic facial types, with the vertical changes being more pronounced in the prognathic cases.