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Larsen Syndrome is a rare inherited severe disease that described for the first time in the medical field as a distinct disease by Dr. Loren Larsen in 1950. It is characterized by congenital dislocation of multiple joints along with other anomalies, including heart, face, hands, and bones. We present a two years five months male who presented with facial dysmorphic features like low set of ears, depressed nasal bridge, micro-retrognathia, and broad forehead. [ABSTRACT FROM AUTHOR]

Skeletally mature patients with cleft lip and palate commonly present with skeletofacial deformities characterized by varying degrees of intrinsic and acquired dentoskeletal and soft tissue abnormalities. These abnormalities are associated with scarring from previous surgeries and the asymmetric midline and facial contour that impose challenges for adequate reconstruction. These patients frequently require 2-jaw orthognathic surgery to improve occlusal function and for correction of facial deformities. In this article, we have detailed a 3-dimensional computer-assisted single-splint 2-jaw orthognathic surgery technique as a surgical approach for cleft skeletofacial reconstruction, allowing for the surgery to be tailored according to the specific needs and requests of the patients. Further, we have addressed the multidimensionality and specificities of cleft treatment, the wide versatility, adaptability, and applicability of this technique, and the patient-centered rationale for the adoption of this method. [ABSTRACT FROM AUTHOR]

Objective: To analyse oral health related quality of life (OHRQoL) several years after orthognathic treatment in patients who had Class II malocclusion with retrognathic mandible.Material and methods: The initial study cohort comprised 151 patients with orthognathic treatment in 2007-2011. Of them, 77 patients (Group 1, mean age 41 years, range 19-71 years, 71% women) were clinically examined 6 years (range 4-8 years) after bilateral sagittal split osteotomy (BSSO). Group 2 included 24 former patients (mean 48 years, range 25-79 years, 50% women) who were willing to participate in a structured telephone interview. Group 3 consisted of 22 prospective patients (mean 35 years, range 18-56 years, 86% women) with a recent orthognathic treatment plan and awaiting treatment. QoL was assessed using two questionnaires, OHIP-14 and OQLQ.Results: Based on responses, patients who had received orthognathic treatment (Groups 1 and 2) had better QoL than those awaiting treatment (Group 3).Conclusion: Conventional orthognathic treatment, including mandibular advancement with BSSO, seems to have a positive long-term effect on patients' QoL. More long-term follow-up studies are needed to assess the real impact of treatment on patients' lives in the long run. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the prevalence of skeletal factor (maxillary excess and /or mandibular deficiency) for the skeletal class II and class III malocclusion in South Indian population. Lateral cephalograms of 100 individuals of either gender in the age group of 18-30 years were selected by using random sampling method during the period of October 2019 to March 2020 having malocclusions were included in the study. The parameters such as ANB of steiner's analysis was used to discrete the skeletal malocclusion into 3 groups such as skeletal class I malocclusion (ANB angle between 0-4 degrees), skeletal class II malocclusion (ANB angle >4 degrees), skeletal class III malocclusion (below -1 degrees). SNA angle used for maxillary skeletal assessment and SNB angle used for prediction of mandibular assessment. The data was collected and subjected to descriptive statistics and inferential (Chi-square) statistics. The results of the study showed that 80% of the studied sample size had Skeletal class II pattern among other skeletal class I (15 %) and skeletal class III (5%) malocclusion. A statistically non-significant association was found between gender and malocclusion using Chi square test (P<0.05). Among total skeletal class II malocclusions, Prognathic maxilla was 54% and retrognathic mandible was 43% and combination of above two was 4%. Among total skeletal class III malocclusions, mandibular prognathism was (60%) and retrognathic maxilla was 40%. The present study concluded that Skeletal class II is the most prevalent malocclusion among other skeletal malocclusions. Prognathic maxilla is the contributing factor for skeletal class II malocclusion and mandibular prognathism for skeletal class III malocclusion. [ABSTRACT FROM AUTHOR]

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Background: Pediatric obstructive sleep apnea/hypopnea syndrome (OSAHS) is a multifactorial syndrome caused by many risk factors, such as craniofacial anomalies, adenotonsillar hypertrophy, obesity, and airway inflammation. Although new treatment patterns have recently been proposed, treatment methods for children remain particularly challenging and controversial. This randomized controlled trial was designed to investigate the efficacy of adenotonsillectomy and/or orthodontic treatment for children who have mild OSAHS with mandibular retrognathia.Methods: A sample of 352 children with mild OSAHS and mandibular retrognathia, who are aged between 7 and 10 years, will be enrolled in the study. They will be randomized into four groups: the drug treatment group, the surgical treatment group, the orthodontic treatment group, or the surgery and postoperative orthodontic group. After randomization the children will receive treatments within 4 weeks. Outcome assessment will take place at the following points: (1) baseline, (2) 7 months after the treatment starting point, (3) 12 months after the treatment starting point, and (4) 24 months after the treatment starting point. The primary endpoint of the trial is the mean change in obstructive apnea/hypopnea index. Other endpoints will consist of the lowest oxygen saturation, apnea index, and hypopnea index assessed by polysomnography, subjective symptoms (assessed by the OSA-20 questionnaire), cephalometric measurements, and morphologic analysis of the upper airway.Discussion: The results of this study will provide valuable evidence for the merits and long-term efficacy of different treatment approaches and contribute to facilitating the multidisciplinary treatment of pediatric OSAHS.Trial Registration: ClinicalTrials.gov : NCT03451318. Registered on 2 March 2018 (last update posted 19 April 2018). [ABSTRACT FROM AUTHOR]

Purpose: To report a rare case series of 14 patients of the Marcus-Gunn jaw-winking phenomenon (MGJWP) without ptosis.Methods: This was a retrospective noninterventional case series. The medical records of all patients diagnosed with MGJWP over the past 10 years were retrieved. Patients with documented evidence of absence of ptosis were segregated and analyzed for visual acuity, the severity of Marcus-Gunn, the presence of squint and amblyopia, and the presence of other aberrant regenerations.Results: A total of 207 patients were diagnosed with MGJWP, out of which 14 (6.76%) patients had isolated MGJWP without blepharoptosis. The mean age of presentation was 9.5 years and males and females were equally affected. The left eye was involved more commonly (57.2%) than the right eye. Twelve patients were congenital and two were presumed to be of traumatic origin. The most common refractive error in this cohort was astigmatism (10, 71.42%), followed by hyperopia (5, 35.71%). One patient had anisometropic amblyopia. Marcus-Gunn was found to be mild (≤2 mm of lid excursion) in all cases. None of the patients had strabismus or any other aberrant innervations. None of the patients underwent surgery and did not develop ptosis or worsening or improvement of Marcus-Gunn after a mean follow-up period of 2.3 years.Conclusion: Isolated MGJWP in the absence of ptosis is a very rare entity and this is the largest series to date to report such an occurrence. All patients had a mild form of MGJWP with no intervention required in any of the cases. [ABSTRACT FROM AUTHOR]

Bone is a dense, semi rigid, porous, calcified connective tissue forming the major portion of the skeleton of most vertebrates. It consists of a dense organic matrix and an inorganic mineral component. Bone remodelling is a complex process by which old bone is continuously replaced by new tissue, which requires interaction between different cell phenotypes and is regulated by a variety of biochemical and mechanical factors. In a homeostatic equilibrium, the process of resorption and formation are balanced so that old bone is continuously replaced by new tissue and it adapts to mechanical load and strain. Several local and systematic factors which cause disturbances in bone resorption and deposition leads to abnormal or defective development of bone commonly termed as osteodystrophy - A defective ossification of bone usually is associated with disturbed calcium and phosphorus metabolism. The better understanding of molecular cellular biology and pathogenic mechanism aids to define the abnormalities in osteoblastic and osteoclastic lineages and to develop new therapeutic approaches. [ABSTRACT FROM AUTHOR]

Class II malocclusion may present with skeletal features of mandibular retrognathism, midface protrusion, and dental features of distal step molar relation, an unusually large overjet and variable combination of these features. With a variety of craniofacial morphology associated with Class II malocclusion, the type of functional appliance (FA) to choose and the timings of treatment are fundamental to treatment outcome and prognosis. Mandibular retrognathism has befallen to be the most universal rationale for availing orthodontic treatment. FAs have come a long way since the introduction of "bite-jumping" appliance by Norman Kingsley with gradual evolution of these appliances through monobloc, activator, Frankel, bionator, twin block appliance and fixed functional appliances which can now be attached to facial skeleton with implant anchorage. Although timing of treatment, mode of their action, treatment benefits and mechanism of craniofacial adaptation have been researched extensively, the subject of FA has always been a matter of discussion with conflicting views. Functional appliance is an effective way of treating skeletal Class II malocclusion in children and adolescents. A 12-month stepwise mandibular advancement protocol has been proved to enhance the condylar growth and improve the mandibular retrognathism. The aim of this review is to discuss the role of functional appliance in the treatment and management of mandibular retrognathism. [ABSTRACT FROM AUTHOR]

Purpose: Gaucher disease (GD) is a lysosomal storage disease caused by an autosomal recessive inherited deficiency of the lysosomal enzyme glucocerebrosidase. The aim of this study is to describe jaw bones' involvement and dental radiographic features in paediatric Gaucher disease patients (type I and type III). Methods: The study population of this case–control study included: 42 Gaucher patients (study group) and 84 medically free children (control group). The radiographic images of both groups were analysed for the following findings: generalised bone rarefaction, localised rarefaction and enlarged bone marrow spaces, thinning of cortex, pseudocystic radiolucent lesions, anodontia and dental anomalies. Dental age assessment of Gaucher patients using the Demirjian's method was also performed. Results: Generalised rarefaction showed almost similar percentages in both types of Gaucher disease cases. Localised rarefaction was noted in 30.77% and 18.75% of Gaucher disease type III and type I, respectively. Pseudocystic radiolucent lesions, thinning of cortex, anodontia and dental anomalies were more prevalent in type III Gaucher patients. The mean chronological and mean dental ages in both sexes of Gaucher patients were not statistically significant. Conclusion: Thinning of cortex, localised rarefaction and generalised rarefaction are the most common jaw bone findings in Gaucher patients. [ABSTRACT FROM AUTHOR]

Vertical malocclusion is a developmental condition, resulting from complex interactions among multiple etiological factors during the growth period. As a tricky dentofacial deformity clinically, long-face (LF) morphology is characterized by excessive vertical facial growth with severe disarrangement of jaws and teeth. Since the improvement of LF patients on facial profile and occlusion is often difficult and lacks long-term stability, it becomes important to unravel the etiology of LF pattern formation for early prevention and treatment. In the current studies, we identified a transgenic mouse model that exhibited a dysplastic coronoid process and LF morphology. Although the mutant mice exhibited jaw structures and occlusion comparable to controls at birth, they all acquired typical LF morphology with anterior open bite during postnatal growth, resembling clinical features of the selected skeletal class III patients. Since the coronoid process provides an insertion site for the temporalis attachment, we examined the initial development and differentiation of the temporalis and found identical results in both control and mutant mice before E17.5 when the temporal muscle makes attachment to the coronoid process. However, thereafter, we observed altered orientation and reduced size of the cross-sectional area of the temporalis in mutant mice, which persisted to the weaning stage. Biomechanical analysis and simulation modeling further support the idea that altered morphology of the coronoid process may impair the efficiency of the vertical temporalis contraction and appears to correlate with LF formation. Consistently, we present evidence that a dysplastic mandibular coronoid process was also seen in some human patients with skeletal III LF morphology. Taken together, the results presented in this study establish an association of the craniofacial bony structures with vertical patterning, which will have implications in earlier prediction for clinical precaution and intervention. [ABSTRACT FROM AUTHOR]

In clinical dentistry practice, supplemental bone surgery or jawbone defect after tooth extraction must be assisted by a bone-filling material. Cobalt-substituted hydroxyapatite (COHA) effectively promotes bone cell growth, reduces the inflammatory response, and is an antibacterial agent. COHA can therefore be used as an alveolar bone-filling material or guided bone regeneration membrane. Meanwhile, COHA can be used in magnetic resonance imaging (MRI) with negative contrast agents and targeting materials without causing metal interference with the image. Hence, COHA has received increasing amounts of attention in recent years. However, the influence of different cobalt precursors on the synthesized COHA is still unknown. Therefore, COHA synthesized from 3 cobalt precursors (cobalt chloride, cobalt nitrate, and cobalt sulfate) was compared in this study. The results show that COHA synthesized by the precursor with the smallest anion radius, cobalt chloride, has a larger particle size (239 nm) and a higher cobalt ion substitution rate (15.6%). When the cobalt ion substitution rate increases, the MRI has a stronger contrast. Bioactivity data indicate that COHAC is more susceptible to degradation and therefore releases more cobalt ions to contribute to the differentiation of bone cells. Based on these studies, COHAC prepared with the cobalt chloride precursor has a higher cobalt ion substitution rate, faster degradation rate, better image contrast, and better bioactivity. It is therefore the preferred choice of bone-filling material for alveolar bone regeneration. [ABSTRACT FROM AUTHOR]

Objective: To assess the lower pharyngeal airway sagittal width on lateral cephalograms before and after the use of a mandibular advancement device (MAD) on Class II patients and to compare the results to a control group of non-treated Class II individuals.Methods: All patients were Class II, ranging in age from 9 to 12 years. They were all treated with a MAD, referred to as a ligated anterior repositioning splint, which was fixed in the mouth for full-time wear. Measurements of the lower pharyngeal airway were made on before- and after-treatment cephalograms. A control group of Class II patients of similar age were selected from several growth studies, and comparisons were made.Results: A significant increase (p < .01) resulted from the treatment group; there was no change from the controls.Conclusion: These findings support the effectiveness of a MAD to increase the lower pharyngeal airway in growing Class II patients. [ABSTRACT FROM AUTHOR]

Purpose. To investigate the association of ptosis, levator, and jaw winking in Marcus Gunn jaw-winking synkinesis (MGJWS), and the risk factor of preservation and outcomes of the unilateral levator excision and frontalis suspension. Methods. Clinical features of MGJWS case series from 2011 to 2018 were retrospectively reviewed. Association between jaw winking and ptosis/levator function was statistically analyzed. The patients underwent unilateral levator excision and frontalis suspension using silicone rod or autogenous fascia lata. Clinical outcomes were evaluated in operated patients and the independent risk factors of residual jaw winking were investigated after a long follow-up. Results. There were 42 MGJWS patients in 2011 to 2018, accounting for 2.87% of all congenital blepharoptosis. 80% of mild jaw winking was accompanied with mild ptosis and fair levator function, and moderate-to-severe jaw winking was often accompanied with moderate-to-severe ptosis and poor levator function (P<0.05). Ptosis showed a strong association with excursion of jaw winking (R = 0.785, P<0.01). Jaw winking was resolved in all 34 operated patients with good correction of ptosis. Severity of jaw winking is an independent risk factor for the residual synkinesis after surgery. Severe preoperative jaw winking had an 18.05 times increased risk of postoperative residual synkinesis compared with moderate jaw winking (P<0.05). Conclusions. In MGJWS eyelid excursion of jaw winking has a direct correlation with ptosis and dysfunction of levator muscle. Unilateral levator aponeurosis excision and frontalis suspension is an efficient approach for MGJWS. Severe jaw winking is a risk factor of residual eyelid synkinesis after surgery. [ABSTRACT FROM AUTHOR]

Aims: To test if the disappearance of clicking associated with anterior disc displacement with reduction (ADDR) is related to a gradual loss of reducing capacity of the disc in the temporomandibular joint. Materials: Twenty-five ADDR subjects without and 30 ADDR subjects with intermittent locking participated in this 2-year follow-up study. Clinical examinations and mandibular movement recordings were performed at baseline and after 1 and 2 years. If mandibular movement recordings no longer showed signs of an ADDR, magnetic resonance imaging (MRI) of the disc was carried out. Results: Mandibular movement recordings showed the moment of disc reduction (MDR) to be stable over the observation period in the subjects without intermittent locking (P = .95). In the subjects with intermittent locking, MDR had shifted to a later mouth opening (P = .000). In seven of these subjects, clicking had totally disappeared, usually without symptoms of permanent locking. On the MRI scans of these subjects, the disc displacement was still present, but with no, or only a partial, reduction. Conclusion: Intermittent locking may be indicative of the development of a disc displacement without reduction. This loss is only rarely accompanied by symptoms of permanent locking. [ABSTRACT FROM AUTHOR]

The size and shape of the jaws are related to occlusion and masticatory muscle function. Consequently, teeth and muscles are considered the functional matrix for the two jaws. Existing studies did not focus on the relationship between maxillary and mandibular base but on just their absolute dimensions. As the relationship between the two is of interest to orthodontists, the aim of this study was to calculate the maxillary-mandibular ratio (m-m ratio) in individuals from Central Italy and to compare it to that of ancient skulls from the same geographic area. Methods: Forty individuals from Opi, a small, isolated mountain village in Central Italy, and 40 ancient skulls from the same region were the sample of this study. The lengths of the maxillary and mandibular base were assessed on lateral cephalograms, the m-m ratio was calculated, and the measurements between the groups were compared. Results: Due to a significantly shorter maxillary base in the modern human sample, the m-m ratio was significantly lower in these subjects. Conclusion: This finding supports the hypothesis that growth of the skull is strongly modulated by the functional matrix, within which a morphologic unit develops. [ABSTRACT FROM AUTHOR]

Regional odontodysplasia is a rare developmental anomaly of the teeth that affects enamel and dentin. Its etiology is unknown, but the most accepted theory refers to circulatory disorders associated with vascular nevi. An uncommon case of regional odontodysplasia involving three quadrants of the jaws is reported. An 8-year-old boy was referred to the authors' institution with lack of teeth as a major symptom. There was no hereditary anomaly in the family. Extraoral examination revealed a brown discoloration on the skin on the right side of the face, neck, and chest. Detailed intraoral examination showed hypoplastic and carious teeth. Fistulae and gingival overgrowth were also observed. Radiographically, the affected teeth presented the pathognomonic image of "ghost teeth." Conservative treatment was instituted. [ABSTRACT FROM AUTHOR]

Aim: To evaluate the long-term result of chin-cap treatment in patients with a skeletal Angle Class III relationship due to mandibular prognathism. Material and Methods: Records of nine patients (five girls and four boys) with a mean age of 10.8 ± 1.6 years at the start of treatment were retrieved from the archives. The records comprised lateral cephalograms, intra- and extraoral photographs, and dental casts. The subjects were recalled at 6.1 ± 1.5 years after the completion of active orthodontic treatment. Cephalometric measurements from the treatment's beginning (T1), end (T2), and follow-up (T3) were calculated by using PorDios software. Subjects with a positive overjet at T3 were grouped as stable, and those with a negative overjet were grouped as relapse. Differences between the two groups were analyzed by repeated measures analysis of variance (ANOVA) and the Duncan test. Results: Five individuals maintained a positive overjet at T3, while four relapsed as indicated by a negative overjet. SNA increased in the stable group between T2 and T3 but not in the relapse group. Conclusion: About half of the young individuals with a mandibular prognathism treated with a chin cap relapsed over time. The relapse seemed to originate from skeletal rather than dentoalveolar changes. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate continuous and simultaneous variations of thread height and width for an experimental screw-type implant. Materials and Methods: A finite element model of an implant with a Vshaped thread was created. The range of thread height was set at 0.20 to 0.60 mm, and the range of thread width was set at 0.10 to 0.40 mm. Forces of 100 N and 50 N were applied along the implant axis (AX) and an angle of 45 degrees in a buccolingual direction (45-degree BL), respectively. The maximum von Mises stresses in jawbone were evaluated, and the sensitivity of the stress in jawbone to the variables was also evaluated. Results: Under AX load, the maximum von Mises stresses in cortical and cancellous bones increased by 4.3% and 63.0%, respectively, as thread parameters changed. Under 45-degree BL load, maximum von Mises stresses in cortical and cancellous bones increased by 19.3% and 118.0%, respectively. When thread height was from 0.34 to 0.50 mm and thread width was 0.18 to 0.30 mm, the tangent slope of the maximum von Mises stress response curve ranged from -1 to 1. The variation of the maximum von Mises stresses in jawbone was more sensitive to thread height than to thread width. Conclusions: Stress in cancellous bone is more likely to be influenced by thread parameters than stress in cortical bone. A 45-degree BL force is more likely to be influenced by thread parameters than an axial force. A thread height of 0.34 to 0.50 mm and a thread width of 0.18 to 0.30 mm is optimal from a biomechanical point of view. In the design of a screw-type implant, thread height is more important than thread width for the reduction of stress within the bone. [ABSTRACT FROM AUTHOR]

Aims: To determine the association between temporomandibular disorders (TMD) and experiences of jaw injury, third molar removal, and orthodontic treatment, controlling for confounding factors such as age, sex, emotional stress, and oral parafunction. Methods: First-year university students (n = 2,374) were instructed to answer a questionnaire regarding symptoms of TMD, jaw injury, third molar removal, orthodontic treatment, stress, and parafunctional habits. All subjects were classified according to the level of TMD symptoms. Logistic regression was applied to assess the associations of experiences of jaw injury, third molar removal, and orthodontic treatment with presence of TMD symptoms after controlling for age, sex, stress, and parafunctional habits. Results: Of the 2,374 students, 715 students were TMD symptom-positive. They were classified into 7 groups consisting of those with only clicking (group 1), only pain in the temporomandibular joint (group 2), only difficulty in mouth opening (group 3), clicking and pain (group 4), clicking and difficulty in mouth opening (group 5), difficulty in mouth opening and pain (group 6), and all 3 symptoms (group 7). TMD symptoms were significantly associated with jaw injury. Odds ratios were 2.25, 2.47, 3.38, and 2.01 for groups 2, 3, 6, and 7, respectively. Experience of third molar removal was significantly associated with TMD (odds ratio = 1.81 for group 1). No association was found between orthodontic experience and TMD. Conclusion: Experiences of jaw injury and third molar removal might be cumulative and precipitating events in TMD. [ABSTRACT FROM AUTHOR]

Aim: To present the dentofacial changes produced by mandibular body ostectomy in a female patient, 19 years of age, and the patient's 2-year follow-up records. Subject and Treatment: An increased lower facial height and a prominent chin, Angle Class III molar relationship, edentulous gaps in the first premolar regions of the mandible, with overjet and overbite values of -1 mm were observed. Radiographic evaluations revealed impaction of the maxillary right canine. The treatment plan included leveling and coordination of the arches, extraction of the maxillary left first premolar and the impacted canine, and a "rectangular" body ostectomy of 5 mm. Results: Treatment lasted for 24 months. An increase of ANB was observed. Normal overjet and overbite were established. The posterior movement of the lower lip and soft and hard tissue points B and Pg were observed. No major changes were observed for the dentofacial structures at the 2-year follow-up visit. However, slight spacing at the ostectomy sites was present. Conclusion: The rectangular mandibular body ostectomy might be considered an alternative effective method for the correction of mandibular prognathism, particularly when the posterior occlusion is to remain unchanged and when edentulous gaps in the anterior region of the mandible are present. [ABSTRACT FROM AUTHOR]

Arteriovenous malformations (AVMs) are an abnormal collection of blood vessels. They are extremely rare congenital or acquired abnormalities in the structure of blood vessels. These malformations have been associated with severe hemorrhage resulting in significant morbidity and mortality. Gingival bleeding seems to be a common symptom of most documented cases of AVM, and radiographs most often appear normal. A 12-year-old girl who was first examined by a general dentist for occasional bleeding associated with the right mandibular teeth was referred to the University of Istanbul, Faculty of Dentistry. During the suturing process to stop the leakage around the mandibular right first molar, uncontrollable hemorrhage began. Magnetic resonance imaging and angiogram revealed the AVM of the right mandibular body. After embolization with an injection of a mixture of cyanoacrylate and lipiodol, the tooth was extracted and initial periodontal therapy performed. The patient has maintained a satisfactory gingival and oral condition since the completion of dental treatment and establishment of oral hygiene. Clinicians should be aware of these lesions and the impact they can have on routine procedures. Proper recognition and therapeutic intervention can help to avoid serious complications and potentially tragic outcomes. [ABSTRACT FROM AUTHOR]

The removable implant-supported prosthesis is the treatment of choice in some clinical situations. Despite its technically demanding fabrication and the resultant high cost, the bar-latch overdenture provides stability and is easy for patients to manage. A case report illustrating the surgical and prosthetic procedures of this treatment option, including laboratory fabrication, is presented. [ABSTRACT FROM AUTHOR]