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Background: The following study aimed to evaluate the dimensions (anteroposterior, transverse and vertical) of the sphenoid sinuses in the adult population. Materials and methods: The study was conducted as a retrospective analysis of the computed tomography (CT) scans of the paranasal sinuses of 296 patients (147 females and 149 males), who did not present any pathology in the sphenoid sinuses. The CT scans of the paranasal sinuses were done with the spiral CT scanner, without using any contrast medium. After obtaining transverse planes, frontal and sagittal planes were created using secondary reconstruction tool. Results: The anteroposterior dimension was found to be 2.65 cm on average, in the range of 0.5–4.3 cm. The transverse dimension was on average 1.98 cm, ranging from 0.5 cm to 4.9 cm. The average vertical dimension was found to be 2.1 cm, in the range of 0.7–3.7 cm. Conclusions: Due to the high incidence of the anatomical variants of the paranasal sinuses, a CT scan is recommended in all patients before a planned surgery in order to avoid the potential iatrogenic complications. Dimensions of the sphenoid sinuses might point towards more at risk variants, but there is still a substantial amount of research that needs to be done in that aspect.

Összefoglaló. Bevezetés: A hiatus hernia egy anatómiai betegség; gyakoribb előfordulása idősebbeknél jelezheti, hogy a betegség idővel előrehalad, súlyosbodik. Elhanyagolt esetben szövődmények alakulhatnak ki, melyek növelhetik a perioperatív mortalitást. Célkitűzés: A laparoszkópos hiatusrekonstrukciók sebészetében szerzett műtéti tapasztalataink ismertetése mellett igyekeztünk statisztikailag alátámasztható korrelációt találni a rekeszizom-defektus anatómiai paraméterei, valamint a betegek életkora között. Módszer: Retrospektív tanulmányunk keretében elemeztük azon betegeinket, akik laparoszkópos hiatus hernia műtéten estek át egy 58 hónapos (2016. január–2020. október) vizsgálati periódus során. A rekeszi defektus méreteit endoszkópos vonalzóval a műtét közben megmértük, a hiatus oesophagei felszínét standard matematikai formula segítségével számoltuk ki. A sürgősséggel műtétre kerülő betegeink adatait külön elemeztük. Statisztikai analízis: A defektus mérete és a betegek életkora és magassága közötti korrelációt a Spearman-féle ró (ρ)-korreláció segítségével állapítottuk meg. A szignifikanciaszint p≤0,05 volt. Eredmények: Az elektív csoportban 142 operált páciensből 47 beteg mérési adatai feleltek meg a kritériumoknak. Az átlagéletkor 64,7 ± 12,7 év volt, 33 páciens volt nő (70,2%), az átlagos testtömegindex 28,8 ± 5,5 kg/m2 volt. A defektus haránt átmérője és felszíne szignifikáns pozitív korrelációt mutatott a betegek életkorával (p≤0,05). Akut indikációval 5 beteg került műtétre; a defektus méretét illetően hasonló eredményeket tapasztaltunk, mint az elektív csoportnál, 2 esetben azonban súlyos szövődmények alakultak ki. Következtetés: A betegség mögött húzódó anatómiai okok jobb megértése és a megfigyeléseink alapján módosított sebésztechnika reményeink szerint csökkentheti a hosszú távú kiújulások számát a jövőben. Az időben elvégzett elektív beavatkozás alacsonyabb mortalitással, kevesebb szövődménnyel és rövidebb hospitalizációval jár együtt. Orv Hetil. 2021; 162(19): 754–759. Summary. Introduction: Hiatal hernia is an anatomical disease, and the higher incidence for elderly patients suggests that it is progressing over time. Neglected cases can cause serious complications, raising perioperative mortality. Objective: We are presenting our experience in laparoscopic hiatal reconstructions. Our main goal is to find a statistical correlation between the anatomical parameters of the hiatal defect and the patients age. Method: Surgical data were reviewed retrospectively for patients who underwent laparoscopic hiatal hernia repair between January 2016 and October 2020. Dimensions of the hiatal defect were measured intraoperatively with an endoscopic ruler. The defect size was calculated using a standard formula. The acute surgeries were analyzed as a separate arm of the study. Statistical analysis: The correlation between the patients age and the size of the defect were calculated using Spearman’s rho (ρ) correlation. The level of significance was p≤0.05. Result: In the elective group, out of 142 patients 47 met the inclusion criteria. The mean age was 64.7 ± 12.7 years, 33 patients were women, and the mean BMI was 28.8 ± 5.5 kg/m2. Patient age showed significant positive correlation with the transverse dimension and the size of the hiatal defect. 5 patients underwent surgery due to acute indications. We found similarities in the size of the defects; at 2 patients we documented severe complications. Conclusions: A better understanding of the underlying anatomical disorders and the consecutively modified surgical technique will hopefully reduce the long-term recurrencies in the future. The elective surgery performed in the right time results in lower mortality, less complications and shorter hospitalization time. Orv Hetil. 2021; 162(19): 754–759.

Previously, in the case of malocclusion owing to skeletal discrepancy in adults, the amount of tooth movement was limited since there was no reliable skeletal anchorage device. The only way to treat this case was by repositioning the maxilla and mandible via orthognathic surgery, but most patients are reluctant to undergo surgery owing to the risk and expenses incurred. However, with the current introduction and use of miniscrews as temporary anchorage devices, the entire dental arch can be relocated to a target position without surgery, thus broadening the scope of non-surgical orthodontic treatment compared to the past. For a non-surgical approach to improve skeletal discrepancy, anteroposterior, vertical and transverse displacements of the dental arch are necessary. In this case, the localization of the centre of resistance of the whole arch must precede the appliance design with an appropriate biomechanical design. Especially, in the transverse dimension, the envelope of discrepancy is reportedly narrow, and the tooth movement must accompany the orthopaedic correction involving the midpalatal suture expansion. Recently, in adults with transverse maxillomandibular discrepancy, miniscrew-assisted rapid palatal expansion (MARPE) can be performed. Moreover, compared to surgically assisted rapid palatal expansion, MARPE reduces the cost to the patient and achieves clinically acceptable stable maxillary expansion. In this article, we will discuss the role of total arch movement and MARPE in widening the scope of non-surgical orthodontic treatment, despite the inherent limitations of miniscrews' mechanical aspects.

Crowding, protrusion, and class II or end-on occlusion are malocclusions frequently associated with a narrow transverse dimension. The goal of expansion is to reduce the need for extractions in permanent dentition through elimination of arch length discrepancies as well as correction of bony base imbalances. Gaining arch length makes the subsequent fixed appliance treatment easier and shorter. Palatal expansion is usually achieved by using fixed rapid maxillary expansion, but because of the complexity, cost, and increased laboratory steps, this step is sometimes omitted. We have modified the design and screw activation protocol of the removable Schwarz plate in such a way that it gives efficient and stable expansion as well as arch perimeter gain with simpler mechanics. We present the long-term results of 10 such cases treated with this modified expander followed by fixed appliances.

WOS:000543953700001 PubMed: 32596805 In this retrospective study, we aimed to present important anatomical structures and distances for posterior fossa surgery by temporal multidetector computed tomography (MDCT). The temporal MDCT images of 317 adult patients (158 males and 159 females) were retrieved from the hospital's picture archiving and communication system (PACS). In the coronal temporal MDCT views, the cochlea-carotid canal and jugular bulb-mastoid bone outer surface were measured. In the axial MDCT views, the carotid canal-jugular bulb and carotid canal-posterior fossa distances were measured; the carotid canal and jugular bulb anterior-posterior (AP) and transverse dimensions were also measured. The bilateral cochlea-carotid canal, jugular bulb-mastoid bone outer surface, and right carotid canal-jugular bulb distances were significantly greater in the males than those in the females (p < 0.05). The carotid canal-posterior fossa distance was not different in both genders (p > 0.05). The carotid canal-jugular bulb and the carotid canal-posterior fossa distances were greater on the left side than those on the right side in both genders (p < 0.05). In males, the outer surface distance was greater on the left jugular bulb-mastoid bone than that on the right side of that bone (p < 0.05). The difference between the carotid canal AP dimensions was not significant between males and females (p > 0.05). However, the carotid canal transverse dimension, jugular bulb AP, and transverse dimensions were significantly greater in the males than those in the females, bilaterally (p < 0.05). In each gender separately, the carotid canal AP and transverse dimensions were greater on the left side and the jugular bulb AP and transverse dimensions were greater on the right side than those on the left side (p < 0.05). Positive correlations were found between the cochlea-carotid canal, the jugular bulb-mastoid bone outer surface, and the carotid canal-jugular bulb distances as well as between the jugular bulb-mastoid bone outer surface and the carotid canal-posterior fossa distances (p < 0.05). In older patients, the carotid canal-posterior fossa distances were shorter on the left side (p < 0.05). Vascular and neural localizations should be well understood in the operative area before applying the surgical approach in the posterior fossa. Computed tomography (CT) has a greater role in the evaluation of bone structures and vascular canals in this area.

Objectives To determine the three-dimensional changes of the nasal septum (NS), alveolar width, alveolar cleft volume, and maxillary basal bone following rapid maxillary expansion (RME) in consecutive patients with unilateral cleft lip and palate (UCLP). Materials and Methods A retrospective investigation was conducted based on the analysis of cone-beam computed tomography (CBCT) data of 40 consecutive patients with UCLP (mean age 11.1 ± 2.2 years). Scans were acquired prior to RME (T0) and after removal of the expander (T1) before graft surgery. A three-dimensional analysis of the effects of RME on the nasal septum, alveolar width, alveolar cleft volume, and maxillary basal bone was performed. Results No changes in the NS deviation were observed following RME (P > .05). Significant increases of the alveolar transverse dimension were found in the anterior (14.2%; P < .001) and posterior (7.7%; P < .001) regions as well as in the volume of the alveolar cleft (19.6%; P < .001). No changes in the basal bone dimensions and morphology were observed (P > .05). Conclusions Following RME, no changes were observed in the NS and maxillary basal bones of patients with UCLP despite the significant gain in the anterior and posterior alveolar width and the increase of the alveolar cleft defect. Clinicians should be aware that maxillary changes following RME in patients with UCLP are restricted to the dentoalveolar region.

The purpose of this study was to determine whether the measured size of active gastrointestinal hemorrhage was useful in predicting subsequent positive findings at catheter angiography. This was a single-institution retrospective study consisting of 32 patients with computed tomography angiography (CTA) positive for gastrointestinal bleeding who went on to receive catheter angiography. Each CTA was reviewed, with axial measurements of the anterior–posterior and transverse dimensions of the largest foci of hemorrhage recorded. Volumetric analysis was used to measure the volume of hemorrhage. These measurements were performed for both the arterial and portal venous phases. Additionally, the interval growth between the arterial and portal venous phase was also calculated. There was a statistically significant difference in the absolute size of the maximum transverse dimension on portal venous phase imaging (mean = 19.8 mm, p

Introduction Incisional hernias can complicate up to one in four laparotomy procedures, and successful repair remains a significant clinical challenge for surgeons. Recently, the surgical technique of ventral hernia repair (eTEP-RS) has been introduced. Aim To present early results in treating patients with ventral hernia using the eTEP-RS technique and to discuss key technical aspects affecting the safety and efficiency of repair. Material and methods A prospective study of early outcomes was conducted for all ventral hernia patients (hernia orifice between 4 and 8 cm) who underwent eTEP-RS between March 2019 and July 2020. Results As of July 2020, we performed a total of 11 eTEP-RS procedures. The mean duration of the surgery was 204 min (158 to 295). The average size of the treated defect in the transverse dimension was 5.8 cm, and the defect area was 38.5 cm2. The average size of the mesh used was 486 cm2 (280 to 590). After an average follow-up of 7 months (1-17) there was no recurrence or major complication. Based on our initial experiences we present a detailed description of the main aspects of the surgical technique itself, as well as the essential nuances, to enable evaluation of the technique and future popularization. Conclusions The eTEP-RS technique is a safe alternative to open ventral hernia repair and allows for the placement of a large piece of mesh in accordance with current recommendations. Excellent knowledge of the detailed anatomy of the abdominal wall is essential for safe and effective hernia repair.

This case report describes the use of temporary anchorage device (TAD)-supported molar intrusion to correct anterior open bite and achieve overjet correction. A 13-year-old female presented with a Class II skeletal profile, with increased overjet and anterior open bite. She was treated with a combination of intrusion of the posterior teeth and extrusion of anterior teeth. The intrusion of maxillary posterior teeth was done with a palatal TAD and a transpalatal arch on the upper first molars to control the transverse dimension. The patient’s mandibular plane angle was maintained with this treatment approach.

Summary Objective To compare the skeletal and dentoalveolar changes produced by the Damon system's treatment philosophy to traditional orthodontic treatment techniques. Materials and Methods An electronic search in four major databases was completed: Cochrane, PubMed, EMBASE, and Google Beta Scholar on October 5th, 2018. Randomized controlled trials, prospective and retrospective controlled clinical trials were included in this systematic review. The quality assessment of individual studies was done using two different tools: The Cochrane Risk of Bias Assessment Tool (RTCs) and The Methodological Index for Non-Randomized Studies (MINORS) (non-RCTs). Results Seven studies were included for this qualitative analysis. Six studies compared the Damon system to various types of conventional (non self-ligating bracket) system as a comparison group. One study used a quad helix as a comparison for a few months before a full bonding appointment with conventional brackets. The majority of studies found an increase in maxillary inter-canine, inter-premolar, and intermolar distance after the treatment in both the Damon and comparison groups. Yet, all studies concluded that there is no significant difference in the final transverse dimension between the two groups. One study also found that the transverse expansion was achieved mainly by tipping movement of posterior dentition, and a decrease in the posterior buccal bone area was evident in both groups after treatment. Conclusion There is not enough evidence to support the claim that the Damon system allows additional arch expansion with better tipping control than with traditional techniques.

Background The purpose of this study was to evaluate the palatal morphological changes in Anterior Open Bite (AOB) pre-pubertal subjects treated with Rapid Maxillary Expansion and Bite-Block (RME/BB) or Quad Helix with crib (QH/C) when compared with a Control Group (CG) by using Geometric Morphometric Analysis (GMM). Methods AOB group (AOBG) included 30 subjects (20 females, 10 males, mean age 8.1 ± 0.8ys) with dentoskeletal AOB. AOBG was divided in two subgroups according to the treatment strategy: RME/BB group (RME/BBg) included 15 subjects (10 females, 5 males, QH/C group (QH/Cg) comprised 15 subjects (10 females, 5 males). The two subgroups were compared with a CG of 15 subjects (10 females, 5 males) matched for sex, age, vertical pattern, and observation period. Digital upper dental casts were collected before treatment (T1) and at the end of the active treatment (T2). Landmarks and semilandmarks were digitized on dental casts and GMM was applied. Procrustes analysis and principal component analysis (PCA) were performed. Results At T2, RME/BBg when compared with QH/Cg evidenced no statistically significant differences. Instead, RME/BBg showed an increased maxillary transverse dimension and a decreased palatal depth when compared with CG. The comparison QH/Cg vs. CG demonstrated a slight transversal maxillary expansion. Conclusions RME/BBg showed significant changes in the transversal and vertical dimensions with a clear maxillary expansion and a decrease of the palatal depth when compared with QH/Cg and CG. QH/Cg showed a significant slight maxillary expansion and no variation in vertical and sagittal planes when compared with CG.

STUDY OBJECTIVES: Acquiring a better comprehension of obstructive sleep apnea physiopathology can contribute to improving patient selection for surgical treatments. We hypothesize that maxillary transverse deficiency restricts the space available for the tongue, leading to upper airway obstruction during sleep. Our primary hypothesis was that maxillary transverse deficiency increases the prevalence of tongue collapse during drug-induced sleep endoscopy (DISE). The secondary hypothesis was that maxillary transverse deficiency will also increase the prevalence of circumferential collapse at the velopharynx. The exploratory hypothesis was that maxillary transverse deficiency is associated with increased obstructive sleep apnea severity. The objectives of this study were to correlate maxillary morphometric measurements with (1) the anatomic level of obstruction during DISE and (2) the apnea-hypopnea index on polysomnography. METHODS: We made a cross-sectional analysis of patients with obstructive sleep apnea undergoing DISE in search of positive airway pressure alternative treatment. Maxillary measurements were collected from a computed tomography scan (interpremolar distance, intermolar distance [IMD] and sella-nasion A point angle), findings from DISE, and sleep study variables from polysomnography. Correlation between computed tomography, DISE, and polysomnography data was assessed using Pearson’s correlation, and receiver operating characteristic curves were determined for each facial measurement. RESULTS: Sixty-nine patients were included in the study. The group with velopharyngeal circumferential collapse had mean IMD = 26.30 mm (25.5–31.45), and the group with anteroposterior collapse had mean IMD = 29.20 mm (26.8–33.10; P = .040). The group with complete tongue-base obstruction had mean interpremolar distance = 26.40 mm (25.1–28) and IMD = 26.30 mm (25.6–28.4), and the group without obstruction had mean interpremolar distance = 28.7 mm (27.2–30; P = .003) and IMD = 34.06 mm (32.1–37; P < .001). The receiver operating characteristic curve determined an IMD cutoff of 29.8 mm for predicting tongue-base obstruction. CONCLUSIONS: The maxillary transverse deficiency, identified by reduction in interpremolar distance and IMD, predicted the occurrence of complete tongue-base obstruction, complete concentric collapse at the velopharynx, and multilevel obstruction during DISE. We did not find an association between the maxillary measurements and obstructive sleep apnea severity. These associations hold some promise in ultimately supplanting insights previously available only through DISE. CITATION: Thuler E, Rabelo FAW, Yui M, Tominaga Q, dos Santos V Jr, Arap SS. Correlation between the transverse dimension of the maxilla, upper airway obstructive site, and OSA severity. J Clin Sleep Med. 2021;17(7):1465–1473.

The effective reggeon field theory in zero transverse dimension ("the toy model") is studied. The transcendental equation for eigenvalues of the Hamiltonian of this theory is derived and solved numerically. The found eigenvalues are used for the calculation of the pomeron propagator., 18 pages, 6 figures, ancillary data files attached; to be published in Eur.Phys.Jour. C

espanolLas compresiones maxilares son una de las anomalias mas frecuentes, independiente del tipo de denticion que se este estudiando. Su tratamiento se puede realizar con un aparato expansor ya sea dentosoportado o esqueletalmente soportado, dependiendo de las consideraciones de maduracion biologica del paciente. Se ha demostrado exito en el tratamiento en etapas prepuberales, sin embargo, existe evidencia de una sutura abierta aun en etapas post adolescencia. El objetivo de este estudio es comparar, mediante Cone Beam CT, los efectos de un dispositivo de expansion rapida maxilar esqueletamente soportado, en relacion a los dentosoportados, en adultos jovenes con compresion maxilar. Material y metodo: Se realizo un estudio de tipo observacional retrospectivo, donde se evaluaron nueve pacientes (tres hombres y seis mujeres) con un promedio de edad de 18±5,5 anos,que asistieron al Servicio de Ortodoncia de la Universidad de Chile, durante los anos 2014-2015. Seis pacientes fueron tratados con aparatos dentalmente soportados (tipo Hyrax) y tres pacientes con apartos esqueletalmente soportados (MARPE). A traves de CBCT se tomaron medidas lineares de la dimension transversal anterior y posterior, y medidas angulares de la inclinacion de molares e incisivos para cada grupo en T1 y T2. Resultados: Hubo un aumento significativo en la dimension transversal posterior de ambos grupos. Se presento radiolucidez de la sutura en un 100% de los pacientes tratados con microtornillos y 50% de los pacientes tratados con hyrax. Hubo mayor angulacion de molares en el grupo dentosoportado en comparacion al grupo esqueletalmente soportado. Conclusiones: Ambos aparatos lograron un aumento de la dimension transversal posterior, sin embargo, los de anclaje esqueletal lograron una expansion mas paralela y esqueletal. Hacen falta ensayos clinicos aleatorizados con mayor muestra y seguimiento. EnglishMaxillary constrictions are one of the most frequent abnormalities, regardless of the type of dentition studied. They can be treated either with tooth-borne or bone-borne expander appliances, depending on the biological maturation of the patient. Treatment during prepubertal stages has been shown to be successful, but there is evidence of an open suture even in late adolescence stages. The aim of this study is to compare the effects of a rapid expansion bone-borne device to a tooth-borne device in young adults suffering from maxillary constriction, by means of Cone-Beam Computed Tomography. Materials and methods: A retrospective observational study was conducted in nine patients (three males, six females) with a mean age of 18±5.5 years, who attended the Dentistry Service of Universidad de Chile during 2014-2015. Six patients were treated with tooth-borne appliances (Hyrax type) and three patients with bone-borne appliances (MARPE). Linear measurements of the anterior and posterior transverse dimension and angular measurements of the inclination of molars and incisors were obtained through CBCT for each group in T1 and T2. Results: A significant increase in the posterior transverse dimensions in both groups was observed. Radiolucency of the suture was observed in all patients treated with miniscrews and in half of the patients treated with Hyrax. Greater angulation of molars was shown in the tooth-borne group in comparison with the bone-borne group. Conclusion: Both appliances caused an increase in the posterior transverse dimension, but bone anchored appliances achieved a more parallel and skeletal expansion. Randomized clinical trials with a larger sample and follow-up are needed.

This paper describes four decades of research carried out at the University of Michigan that has investigated the clinical alteration of the transverse dimension of the face, with specific attention given to orthodontic and orthopedic treatment of patients in the early mixed dentition. The results of a series of clinical studies beginning in the late 1970s are described that consider the etiology of dental crowding as well as treatment effects produced by expansion in the late mixed/early permanent dentition and the early mixed dentition. A treatment protocol for early treatment is described that includes the lower Schwarz appliance, a bonded acrylic splint expander and the placement of anterior brackets. A series of retrospective and prospective studies are presented, including a study investigating the spontaneous improvement of Class II malocclusion following increases in the transverse dimension. The effect of maintaining or increasing anterior arch length on subsequent mandibular second molar eruption is evaluated. The ideal timing for rapid maxillary expansion is before puberty. An individual assessment of the midpalatal suture using cone-beam computed tomography (CBCT) images can be useful when making a clinical decision between conventional and surgically assisted RME, especially for adolescent and young adult patients.

Problems in the transverse dimension can be challenging to manage, especially in adult patients. The purpose of this article is to provide a review of normal transverse jaw development, the etiology and diagnosis of transverse discrepancies, goals of adult transverse treatment, and treatment options for adult transverse discrepancies. Mirroring a seminar from your orthodontic residency, this article is written in question and answer format. We ask that you think through answers to the questions we present very carefully and make the best decisions you can, before you refer to the answers we provide. Like your orthodontic residency, you will find that certain principles are emphasized and applied time and time again to a spectrum of patients in this case-based article. These are the principles which have served us well over many years of teaching and treating adults in the transverse dimension.

Aim The study tests the correlation between the enlargement of the nasal cavity width, interglenoid fossa distance, and intercondylar distance after rapid maxillary expansion (RME) in growing patients. Materials and methods Cone beam computed tomography (CBCT) was performed for 25 patients presenting a bilateral crossbite (11 males, 14 females, and mean age 11.6 ± 1.6 years) at baseline (T0) and at 6 months after RME (T2), T1 being the end of expander activation. Images were digitized for linear measurements using specific software. Values were compared at the nasal width, interglenoid fossa distance, and intercondylar distance to test the correlation in the transverse dimension. Results At T0, a correlation already existing between the interglenoid fossa distance and the intercondylar distance persisted at T2. The correlation between the nasal cavity width and interglenoid fossa distance nonexistent at T0 ended toward statistically significant at T2. Additionally, the lateral position of the condyles was not correlated with the nasal cavity width neither at T0 or T2. Conclusion A correlation between the interglenoid fossa distance and intercondylar distance was exhibited 6 months after RME. The correlation between the nasal cavity width and interglenoid fossa distance was close to significant at T2.

Objective The potential significance of relationship of atlantoaxial instability with retro-odontoid pseudotumor, pannus, and/or cyst (RPC) is analyzed. Methods We searched the database of patients with craniovertebral junction–related instability treated by atlantoaxial fixation from January 2000 to March 2020. We identified 63 patients in whom there was an RPC in the region posterior to the odontoid process or posterior to the posterior aspect of the C2 body. Results The RPC was solid in 10 patients, predominantly cystic in 39 patients, and had both solid and cystic components in 14 patients. The vertical dimension of the RPC varied from 4.5 to 10.5 mm (average, 7.9 mm) and the transverse dimension ranged from 2 to 5.2 mm (average, 3.4 mm). In 51 patients, the RPC was in the midline and in 9 patients, it was eccentric in location. In 38 patients, there was erosion of the C2 body adjoining the RPC. Analysis of investigations showed that in 100% of patients, the dome of the RPC was in line with the most susceptible point of potential bone compression of neural structures. The RPC was eccentric in location in 9 patients presenting with torticollis. RPC indicated the presence of atlantoaxial instability even when there were no other positive and validated radiologic indicators. After atlantoaxial stabilization, the RPC spontaneously regressed or disappeared. Direct resection of the RPC was neither performed nor was necessary in any case. Conclusions RPCs are secondary consequences of atlantoaxial instability and need not be primarily addressed by surgical resection. Their location suggests that they might have a neural protective function.

Introduction: Cleft Lip and Palate (CLAP) is one of the most frequent craniofacial anomalies. The management of patients with CLAP requires several repair procedures for the soft palate, the primary and secondary bony palate, the alveolar ridge, the lips and the nose. These patients often present with a maxillary transverse deficit responsible for maxillary endognathy which must be corrected for a harmonious development of the maxillomandibular complex. The objective of our work was to evaluate the efficacy of slow, rapid and surgical maxillary expansion in patients with sequelae of CLAP following a systematic review protocol. Materials and methods: Four databases were searched: PubMed / MEDLINE, ScienceDirect, Cochrane Library and EBSCOhost, using the keywords present in the MeSH according to the equation [Maxillary expansion] AND [Cleft lip and palate]. The selection of articles included all studies published since January 2010 and for which the full text is available, such as meta-analyzes, randomized and non-randomized controlled clinical trials, case-control studies and prospective and retrospective studies. Results: Among 1107 references only 8 studies met our inclusion criteria. Following analysis of these, we concluded that there is no significant difference between rapid maxillary expansion and slow maxillary expansion in patients with unilateral CLAP, the expansion observed on the side of the cleft is larger than that seen on the healthy side. Surgically assisted expansion is much more reserved for subjects at the end of growth, having unilateral or bilateral CLAP and presenting anterior or posterior lateral crossbones. The results of our systematic review also showed that maxillary expansion in patients with CLAP results in substantial dentoalveolar compensation. Conclusion: The efficacy of maxillary expansion in patients with sequelae of CLAP is real and alone in some cases allows the restoration of a normal transverse dimension; sometimes in combination with maxillary protraction to correct the anteroposterior deficit.

Biocreative Orthodontic Strategy (BOS) is designed to establish a physiologically stable occlusion in harmony with masticatory and TMJ function and healthy supporting tissues with strategic use of temporary skeletal anchorage devices (TSADs). This narrative review surveys current research that demonstrates how BOS with TSADs uses a target approach to overcome the limitations experienced with conventional orthodontic treatment. A narrative review article including research on TSADs orthodontics in the permanent dentition. This review is a brief survey of five BOS principles for contemporary TSAD orthodontics: elegant selection of TSADs, bracket prescription to enhance TSAD orthodontics, antero-posterior dimension control, transverse dimension control and airway control issues. Severe malocclusion and craniofacial dysmorphology can be treated with Biocreative Orthodontic Strategy with a minimum number of TSADs. In order to achieve successful treatment outcome using TSADs, it is critical to understand the key diagnosis and treatment principles of BOS and how to develop a target approach for the tooth and bone movement.

Variations in craniofacial morphology may arise as a result of adaptation to different environmental factors such as soft diet (SD), which lessens functional masticatory load. Prior studies have shown that changes in the masticatory muscle function associated with a switch to short-term SD led to changes in craniofacial morphology and alveolar bone architecture. However, the long-term effects of SD and the associated adaptive changes in craniofacial shape are unclear. Our novel study set out to profile prospective skull changes in mice fed with SDs over multiple generations using three-dimensional (3D) geometric morphometric analysis (GMA). Our results revealed that short-term SD consumption led to a significant decrease in craniofacial size, along with numerous shape changes. Long-term SD consumption over 15 continuous generations was not associated with changes in craniofacial size; however, shape analysis revealed mice with shortened crania and mandibles in the anteroposterior dimension, as well as relative widening in the transverse dimension compared to the average shape of all mice analyzed in our study. Moreover, changes in shape and size associated with different functional loads appeared to be independent - shape changes persisted after diets were switched for one generation, whereas size decreased after one generation and then returned to baseline size. Our study is the first to study the role of prolonged, multi-generational SD consumption in the determination of craniofacial size and shape.

The purpose of this prospective study was to investigate medium-term indirect effects of Maxillary Expansion (RME) therapy on mandibular arch dimensions using two different clinical protocol activation. Sixty patients in mixed dentition (mean age 7.8 y) showing maxillary deficiency and/or unilateral or bilateral cross-bite were treated with RPE (Haas type) on second deciduous molars. For patient in RME group (rapid maxillary expansion), treatment protocol consisted of 2 turns per day: For patient in SME (slow maxillary expansion) group treatment protocol consisted of 2 turns per week. Study models were taken before (T1) and after expansion (T2) with 12 ± 4 months interval. Dental cast were digitized with a 3D scanner (3Shape, DK) and a set of landmarks was digitized on each digital model. Mandibular intermolar distance (MID), mandibular molar torque (MMT), mandibular intercanine distance (MIcD) and mandibular canine torque (MCT) were assessed. At T1, no differences at baseline were found between groups. At T2, in RME group, mandibular intermolar distance (MID) increased 1.2 mm and MMT increased 6.5°. In SME group MID increased 1.3 mm and mandibular molar torque (MMT) increased 6.2°. There was a significant effect on mandibular intercanine distance (MIcD) (RME +0.8 mm, SME +0.9 mm) and on and mandibular canine torque (MCT) (RME +3.4°, SME +3.8°). The improvement in transversal and torque measurement did not differ between groups. In conclusion, both rapid and slow maxillary expansion protocols have a significant medium-term widening effect on the mandibular first molars and canines.

An understanding of fundamental orthodontic principles involving diagnosis, treatment planning, and clinical strategies is essential for achieving successful outcomes in the treatment of craniofacial patients, particularly cleft lip/palate. This article focuses on: customizing a mandibular dental arch form using the WALA ridge; accurately diagnosing the maxillary skeletal transverse dimension (cusp to cusp/fossa to fossa); coordinating the upper dental arch with the lower; using a smiling profile and glabella vertical to assess anteroposterior jaw position; and leveling the mandibular curve of Spee while considering the lower one-third of the face. These concepts influence treatment outcomes to the extent they are used.

The objective of this work was to perform image-based classification of abdominal aortic aneurysms (AAA) based on their demographic, geometric, and biomechanical attributes. We retrospectively reviewed existing demographics and abdominal computed tomography angiography images of 100 asymptomatic and 50 symptomatic AAA patients who received an elective or emergent repair, respectively, within 1–6 months of their last follow up. An in-house script developed within the MATLAB computational platform was used to segment the clinical images, calculate 53 descriptors of AAA geometry, and generate volume meshes suitable for finite element analysis (FEA). Using a third party FEA solver, four biomechanical markers were calculated from the wall stress distributions. Eight machine learning algorithms (MLA) were used to develop classification models based on the discriminatory potential of the demographic, geometric, and biomechanical variables. The overall classification performance of the algorithms was assessed by the accuracy, area under the receiver operating characteristic curve (AUC), sensitivity, specificity, and precision of their predictions. The generalized additive model (GAM) was found to have the highest accuracy (87%), AUC (89%), and sensitivity (78%), and the third highest specificity (92%), in classifying the individual AAA as either asymptomatic or symptomatic. The k-nearest neighbor classifier yielded the highest specificity (96%). GAM used seven markers (six geometric and one biomechanical) to develop the classifier. The maximum transverse dimension, the average wall thickness at the maximum diameter, and the spatially averaged wall stress were found to be the most influential markers in the classification analysis. A second classification analysis revealed that using maximum diameter alone results in a lower accuracy (79%) than using GAM with seven geometric and biomechanical markers. We infer from these results that biomechanical and geometric measures by themselves are not sufficient to discriminate adequately between population samples of asymptomatic and symptomatic AAA, whereas MLA offer a statistical approach to stratification of rupture risk by combining demographic, geometric, and biomechanical attributes of patient-specific AAA.

Made available in DSpace on 2020-12-12T02:45:19Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-01-01 Objectives: The purpose of this study was to evaluate the influence of a palatal splint on stability in multi-segment maxillary osteotomies. Setting and Sample Population: Retrospective series of fifty-one adult patients, consecutively operated with bilateral sagittal split osteotomy (BSSO) and three-piece maxillary osteotomies, divided according to the use of a palatal splint (Group 1, n = 30) or no palatal splint (Group 2, n = 21). Materials and Methods: Maxillary surgical casts (T1) and post-retention casts (T2), taken at least six months after discontinuation of orthodontic retention, were digitized (MicroScribe-3DX), measured and compared. Fifty-one landmarks were identified on the maxillary, transverse dimension changes and arch length were calculated. Longitudinal changes in all measurements were assessed by t test. Results: Post-surgical transverse instability in group 1 ranged from 0.3 ± 0.4 to −1.3 ± 0.2 mm and was statistically significantly smaller than in group 2 that ranged from −1.0 ± 0.3 to −2.5 ± 0.5 mm. Conclusions: The use of a palatal splint after segmental Le Fort I maxillary osteotomy improved transverse stability in the posterior region. The post-surgical transverse instability occurred only between canine gingival points and thus suggesting no clinical relevance. School of Dentistry São Paulo State University (UNESP) Hospital for Rehabilitation of Craniofacial Anomalies University of São Paulo (USP) Private Practice School of Dentistry São Paulo State University (UNESP)

Purpose Stable orthodontic treatment results require the preservation of the pretreatment mandibular dental arch form. Therefore, this study aimed to evaluate the amount of transverse adjustment of preformed stainless steel archwires require to fit the dental arch form. Materials and methods A fourth-order polynomial curve was applied to the 30 normal mandibular dental arches, and interpolated widths at the mean depths at the canine, first and second premolars, and first molar were measured. Widths of 42 types of 0.016-in. stainless steel preformed archwires were measured at the same mean depths. The widths of the dental arch and archwires were compared by the Mann–Whitney U test. Transverse adjustment values as the difference between dental and archwire widths for each tooth from the canine to first molar were calculated for each archwire and compared between tooth types. Correlation coefficients between tooth types were also analyzed. Results Preformed archwire width was significantly narrower than the dental arch. Significant difference between transverse adjustment values between each tooth type were found except between canine and first premolar. Significant correlations between each tooth types were also observed. Conclusion To reduce these adjustments, preformed stainless steel archwires that are designed to be approximately 1–2 mm at the canine, 1–3 mm at first premolar, 2–4 mm at second premolar, and 3–6 mm at first molar wider in the transverse dimension could be clinically recommended.

Objectives: To evaluate the changes in position of the maxillary dentition and the airway space after distalization using a modified C-palatal plate (MCPP) in adult patients through CBCT images and to analyze the relationship between the amount of distalization and the changes in the airway space. Materials and Methods: CBCT images of 33 adult Class II patients (22.2 ± 4.0 years old; 27 women and 6 men) treated by total maxillary arch distalization using the MCPP were evaluated before and after distalization. The patients were divided into nonextraction and extraction groups. The changes in the airway space as well as the changes in the positions of the maxillary dentition were evaluated. The distalization effects were calculated and assessed using paired t-tests. Results: After distalization, the first molar showed significant distalization and intrusion (P < .001) with no significant rotation of the crown and no significant buccal displacement of its root in the transverse dimension. There were no significant changes in the airway volume or the minimum cross-sectional area of the oropharynx. Conclusions: The application of the MCPP resulted in significant total arch distalization without a significant effect on the transverse dimensions or changes in the oropharynx airway space. The MCPP can be considered a viable treatment option for patients with Class II malocclusion.

An experimental study of the formation of thermocapillary structures at low Reynolds numbers and temperature gradients at the surface of the film in a wide range of the liquid viscosity is performed. The data on the distance between the jets are generalized. It is demonstrated that the transverse dimension of the structures is determined by the capillary constant and does not depend on either the liquid viscosity or the flow rate (Reynolds number of the film).

The aim of this study is to evaluate the longitudinal transverse growth of the maxillo-mandibular complex in untreated children using the Cone Beam Computed Tomography (CBCT). Two sets of scans on 12 males (mean 8.75 years at T1 and 11.52 years at T2) and 18 females (mean 9.09 years at T1 and 10.80 years at T2) were analyzed using Dolphin 3D imaging. The transverse widths of various maxillary and mandibular skeletal landmarks and the dentoalveolar and dental landmarks at the level of first molars were measured. Overall, there were greater increases in the transverse dimension in the posterior than anterior portions of the maxilla and mandible. The increase in intergonial width of the mandible seems to be primarily due to the lengthening of the mandibular body. The dentoalveolar process at the first molar level increases at an equal rate corono-apically and is independent to the changes in molar inclination. When comparing maxillary dentoalveolar changes with that of the mandible, greater increases were noticed in the maxilla, which might be explained by the presence of sutural growth in the maxilla. Moreover, the first molars maintain their coordination with each other despite the differential increase in the maxillary and mandibular dentoalveolar processes.

The calculation results of extended elements of structures according to the theory of beam will be correct if the condition for their length is met, which, as is known, should be much more transverse dimensions. The absence of an exact relationship between the transverse dimensions and the length of the beam is caused by the characteristics of the behavior under a load of various types and shapes of cross-sections: open, closed, thin-walled, etc. In this paper, the ratio of the length of the beam to its transverse dimensions is considered, which provides correct results during its static and dynamic loading, as well as during the loss of stability. To do this, two forms of thin-walled cross-sections are selected: circular and rectangular. The problem solution was carried out both analytically and by the finite element method. The results showed that the most stringent requirements are introduced by the theory of stability, according to which the length should be 15 or more times the largest transverse dimension.