Usefulness of a Titratable Mandibular Positioner During Sleep Endoscopy as a Prediction Tool for Treatment Outcome with Mandibular Advancement Devices: DISE-SAM Protocol

Mandibular advancement devices (MAD) are an effective alternative treatment to CPAP. However, different maneuvers have been performed during the performance of drug sleep-induced endoscopy (DISE) to mimic the effect of MAD. Using the Selector Avance Mandibular (SAM) device, we aimed to identify MAD candidates during DISE using a titratable, reproducible, and measurable maneuver. This DISE-SAM protocol may help to find the relationship between the severity of the respiratory disorder and the degree of response, and to determine the advancement required to improve the collapsibility of the upper airway. Explorations were performed in 161 patients (132 males; 29 females) with a mean age of 46.81 (SD = 11.42) years, a BMI of 27.90 (SD = 4.19) kg/m2 and a mean AHI of 26.51 (SD = 21.23). Results showed no relationship between severity and MAD recommendation. Also, there was a weak positive relationship between the advancement required to obtain a response and the disease severity. Using the DISE-SAM protocol, the response and the range of mandibular protrusion were assessed, avoiding the inter-examiner bias of the jaw thrust maneuver. We suggest prescribing MAD as a single, alternative, or multiple treatment approaches following the SAM recommendations in a personalized design.

Rare case of skeletal third class in a subject suffering from Solitary Median Maxillary Central Incisor syndrome (SMMCI) associated to panhypopituitarism

Background The median solitary maxillary central incisor syndrome (SMMCI) is a rare malformative syndrome consisting of multiple defects, mainly found on the body midline. It can be correlated to the etiopathological and phenotypic pattern of panhypopituitarism. This case-report describes the rare case of a patient suffering from SMMCI and panhypopituitarism, showing an unusual craniofacial morphology. Case presentation From the cephalometric analysis, a skeletal class III was identified (despite the other cases described in literature described as skeletal class II), derived from hypomaxillia and mandibular protrusion. A convex lip profile, with tendency to mandibular hyper-divergency, airway patency, anterior and posterior cross-bite were observed. At the clinical examination, a maxillary cant was evident on the frontal plane that appeared asymmetric, with the prevalence of the third lower part of the face. There were some dysmorphic signs such as: small nose, rectilinear eyelid line and reduced interocular distance. Conclusions The present clinical case shows how, despite the literature, SMMCI can be associated with a III skeletal class, with maxillary hypoplasia and mandibular protrusion. The interdisciplinary collaboration between dentist and pediatrician is therefore important for the early interception of the malocclusions associated with these syndromes.

Incidence and Effects of Posterior Cranial Vault Deformation in Adult Females With Skeletal Class III Malocclusion

BackgroundThe precise characteristics of posterior cranial vault deformation are difficult to identify using a two-dimensional analysis. Recently, three-dimensional analysis using computed tomography (CT) data and software analysis has enabled us to examine the craniofacial structure precisely. To identify the deformation in the cranial vaults by a three-dimensional analysis and examine its effects on other structures, CT data of skeletal mandibular protrusion cases without lateral deviation of pogonion (Pog) were examined.MethodsThirty-two adult female patients with skeletal mandibular protrusion who visited Meikai University Hospital were included in this study. CT images were taken before orthognathic surgeries, and the craniofacial structures were examined threedimensionally.The lateral deviation of Pog was less than 3 mm in all cases.Genetic/congenital anomaly cases, endocrine disorders, or cases with severe trauma or temporomandibular disorder were excluded.ResultsMany cases had three-dimensional deformations in the cranial vaults. The cranial vaults with unilateral posterior deformation had posteriorly positioned mandibular fossae on the same sides. Mandibular body lengths were related to the position of the mandibular fossae, and the posterior mandibular fossae tended to have longer mandibular body lengths on the same sides. Masseter muscles with larger volumes were related to longer mandibular body lengths.ConclusionsMandibular body lengths can compensate for the bilateral difference in the position of the mandibular fossae to avoid lateral deviation of the Pog. The masseter muscles are likely one of the factors related to the bilateral differences in the mandibular body length.

Intervention Proposal for Infant Prognathism: A Case Report in a Non-Syndromic Pediatric Patient

Treating Class III malocclusions has been presently considered one of the most challenging and complex interventions of orthodontic daily practice. In this study, we report a case of a 17-month-old female patient, initially diagnosed with Angle Class III malocclusion, mandibular protrusion, and without genetic syndromes. Upon initial admission at the dental office, patient’s parents reported an inadequate bite pattern while the patient tried to eat solid food. Upon dental examination, a negative overjet of 8 millimeters was noticed and a two-phased treatment plan was established: 1. Performance of functional exercises; 2. Implementation of protractor device associated with masticatory guidance exercises. Radiographic examination and cephalometric analyses were performed throughout the case follow-up. Overall, the digital compression protocol carried out reverted the primary mandibular protrusion of -8 millimeters to +1 millimeters overbite, during the 6 months of treatment. In addition, the use of premaxillary protractor appliance increased the overbite to + 2 millimeters. The patient responded satisfactory to the treatment plan performed, and after 2 years, a proper primary occlusion, oral functionality, and facial aesthetics were improved.

Fixed Functional Appliances

Considering the large number of fixed functional appliances, choosing the best device for your patient is not an easy task. To describe the development of fixed functional appliances as well as our 20-year experience working with them. Fixed functional appliances are grouped into flexible, rigid and hybrid. They are different appliances, whose action is described here. Four clinical cases will be reported with a view in illustrating the different appliances. Rigid fixed functional appliances provide better skeletal results than flexible and hybrid ones. Flexible and hybrid appliances have similar effects to those produced by class II elastics. They ultimately correct class II with dentoalveolar changes. From a biomechanical standpoint, fixed functional appliances are more recommended to treat class II in dolichofacial patients, in comparison to class II elastics. The electromyographic (EMG) activity of masticatory muscles was monitored longitudinally with chronically implanted EMG electrodes to determine whether functional appliances produce a change in postural EMG activity of the muscles. Pre-appliance and post-appliance EMG levels in four experiments that had been fitted with functional appliances were compared against the background of EMG levels in controls without appliances. The insertion of two types of functional appliance to induce mandibular protrusion was associated with a decrease in postural EMG activity of the superior and inferior heads of the lateral pterygoid, superficial masseter, and anterior digastric muscles; the decrease in the first three muscles was statistically significant. This decreased postural EMG activity persisted for approximately 6 weeks, with a gradual return towards pre-appliance levels during a subsequent 6-week period of observation. Progressive mandibular advancement of 1.5 to 2 mm every 10 to 15 days did not prevent the decrease in postural EMG activity. KEY WORDS Orthodontics, Class II Malocclusion, Fixed Functional Appliance.

Comparative Evaluation of Adenoids, Upper Airway, and Tongue Using “Predictors of Difficult Airways” in Class II Division 1 and Division 2 Cases with Class I Cases: Prospective In Vivo Observational Study

Introduction: Altered nasorespiratory function leads to altered craniofacial growth. Thus, airway evaluation is important for preventive, interceptive, and corrective orthodontic treatment. The aim of this study was to evaluate and compare adenoids, the upper airway, the tongue, and mandibular dimensions using “predictors of difficult airways” in class II division 1 and class II division 2 cases with class I cases. Method: Sixty subjects of age 15 to 18 years were divided into 3 groups (group 1: class I cases; group 2: class II division 1 cases; and group 3: class II division 2 cases) based on cephalometric parameters, with 20 cases in each group. Cephalometric evaluation of adenoids and the nasopharyngeal airway was done using the Handelman–Osborne area method. Upper and lower airway evaluation was done using McNamara’s linear method. “Predictors of difficult airways” were used for evaluation of the airway, which included nasal competency, the Mallampati scale, mandibular length, mandibular protrusion, and the thyromental distance. Results: The present study found a significant positive correlation between the grades of nasal competency and percentage adenoid wall area, and a significant negative correlation between the grades of nasal competency and the upper airway. There was a significant positive correlation between the grades of nasal competency and mandibular length, and a significant positive correlation between the grades of mandibular protrusion and mandibular length. There was a significant positive correlation between the grades of the thyromental distance and mandibular length. Conclusion: It was concluded that the “predictors of difficult airways” would be helpful in early diagnosis and identification of potential risk factors that may cause “breathing disorders”–related malocclusions and later on increase the risk of developing OSA.