1,720,966 research outputs found
Orthodontic Correction of Traumatic Luxations, Disadvantages of Continuous Arch Techniques: A Clinical Protocol
No full textThe orthodontic management of traumatic vertical tooth dislocations requires to correct apply biomechanical principles. In fact, the choice between continuous or segmented arch technique is of great importance to avoid side effects on the dental elements adjacent to the traumatized ones. The purpose of the present work is to analyse the biomechanical advantages related to the correct application of mechanical classes according to Burstone. In the management of these situations, a fixed orthodontic appliance is usually used, with a continuous or segmented technique. Two types of techniques were compared: the continuous arch technique and the segmented arch technique, evaluating for each the vectors of single forces and the moments generated by pairs of forces acting on the bracket of the affected element and the anchorage unit. In Author’s opinion, the best choice is segmented mechanic because it allows to avoid a Burstone Class I interaction between the adjacent teeth. A class I mechanic may cause disadvantages: 1) opposite vertical movement of the unaffected tooth 2) less intrusion of the affected tooth 3) uprighting of both affected and unaffected tooth 4) the amount of the force may be inaccurate. These side effects do not exist in a segmented arch technique, because a single precise force passing through the center of resistance of the affected tooth is created, while the anchorage unit is only located on molars
Obstructive Sleep Apnea Syndrome Analysis Using Stereophotogrammetry: A Sistematic Review
No full textAim:
Obstructive sleep apnea syndrome (OSAS) is a disorder characterized by nocturnal breathing interruptions due to upper airway obstruction.
The aim of the review is to verify the existence of any current literature concerning the craniofacial stereophotogrammetric evaluation in order to predict the presence and severity of OSAS. This technology uses a three-dimensional model obtained from multiple frames of the face taken from different angles.
Methods:
The research was performed on MEDLINE-PUBMED without applying temporal or linguistic restrictions. From 19 studies, 4 were selected.
Results:
The study of Banabilh et al. 2009 shows how the severity of OSAS depends on the deposition of submandibular fat, neck circumference and body mass index. According to the study of Lin et al. 2018 numerous measurements concerning areas, volumes and anthropometric lines of the head and neck district indicate the presence and severity of the pathology. In the study of Ohmura et al. 2022 it has been demonstrated that mandibular width, length, depth and width-lenght angle are correlated with OSAS severity. In the study of Tyler et al. 2022 emerged that an increasing obtuse angle of facial convexity is found in severe OSAS subject.
Conclusions:
In this review emerged a correlation between OSAS severity and submandibular fat deposition, neck circumference, body mass index, facial convexity as well as numerous anthropometric parameters from the literature. It should be note the limited amount of scientific material currently available in this regard
Gingival Recessions following Invisible Aligners Treatment. A Retrospective Evaluation.
No full textA correlation between the use of fixed orthodontic appliances (FOA) and the onset of gingival recessions is now widely demonstrated. In 1999, a new type of treatment was introduced, designed, and created with invisible thermo-printed appliances.
It had great success, especially amongst adults, since it gives greater comfort, as the appliances are removed before meals and home oral hygiene practice; it also turns out to be less impactful from an aesthetic point of view, compared to FOA.
AIM of this study is to evaluate the number of gingival recession (REC) before the orthodontic treatment with aligners and compare it with the REC at the end of the treatment and after 5/10 years of a retention phase.
METHODS: 49 patients were involved, for each of whom 3 intraoral photographs were taken at 3 different time points: before treatment (T0), at the end of orthodontic therapy (T1) and after following up from a minimum of 5 to a maximum of 10 years.
Teeth from 15 to 25 showing gingival recessions in the photos between T0, T1 and T2 were recorded.
RESULTS: The data analysis showed that the gingival recessions recorded at time T2, almost doubled compared to those recorded at time T0, i.e., before treatment. In particular, the maximum possible increase in the incidence of recessions occurred between T0 and T1.
CONCLUSION: Orthodontic therapy with aligners may increase the onset of gingival recessions during the treatment or in the retention phase. In future, it will be interesting to compare the occurrence of recessions, in the same time frame, between the treated and an untreated sample
The Paediatric Obstructive Sleep Apnea (OSA): A Study on Knowledge and Attitude among Italian Dentists
No full textAIM
This study aimed to investigate knowledge and attitude about obstructive sleep apnoea (OSA) in children among Italian dentists.
METHODS
An anonymous questionnaire was prepared using Google Forms and sent to dentists in Italy via private social platforms. The first part of the questionnaire contained basic demographic data questions, and the second part included items about paediatric OSA. A total of 125 responses were recorded over one month. For this study, we excluded questionnaires compiled by orthodontists using the answer “no” to the question “have you achieved your orthodontic residency?”.
RESULTS
The general dentists who compiled the questionnaire were in total 85, 35 female e 50 male, with an average age of 46,8 years, from regions of North, Centre and South Italy. About 50% of them reports having never received training about paediatric OSA and about 60% consider their knowledge in that field low. Most of the dentists who participated in this study acknowledge the importance of the multidisciplinary team in the management of OSA in children; despite that, they can’t correctly identify the figures mandatorily involved and the referral to other specialists is infrequent. Moreover, some of the most common risk factors of the disorder remain underestimated and some severe consequence of OSA are not recognized by at least 30% of the interviewed.
CONCLUSION
This study shows lack of knowledge about paediatric OSA and its management among Italian dentists, revealing the need to update the dentistry curriculum and to organize educational interventions
A narrative review on obstructive sleep apnoea syndrome in paediatric population
Full text linkObstructive sleep apnoea syndrome is a respiratory sleep disorder that affects 1–5% of children. It occurs equally in males and females, with higher incidence in school age and adolescence. OSAS may be caused by several factors, but in children, adenotonsillar hypertrophy, obesity, and maxillo-mandibular deficits are the most common. In general, there is a reduction in the diameter of the airway with reduced airflow. This condition worsens during sleep due to the muscular hypotonia, resulting in apnoeas or hypoventilation. While snoring is the primary symptom, OSAS-related manifestations have a wide spectrum. Some of these symptoms relate to the nocturnal phase, including disturbed sleep, frequent changes of position, apnoeas and oral respiration. Other symptoms concern the daytime hours, such as drowsiness, irritability, inattention, difficulties with learning and memorisation, and poor school performance, especially in patient suffering from overlapping syndromes (e.g., Down syndrome). In some cases, the child’s general growth may also be affected. Early diagnosis of this condition is crucial in limiting associated symptoms that can significantly impact a paediatric patient’s quality of life, with the potential for the condition to persist into adulthood. Diagnosis involves evaluating several aspects, beginning with a comprehensive anamnesis that includes specific questionnaires, followed by an objective examination. This is followed by instrumental diagnosis, for which polysomnography is considered the gold standard, assessing several parameters, including the apnoea-hypopnoea index (AHI) and oxygen saturation. However, it is not the sole tool for assessing the characteristics of this condition. Other possibilities, such as night-time video recording, nocturnal oximetry, can be chosen when polysomnography is not available and even tested at home, even though with a lower diagnostic accuracy. The treatment of OSAS varies depending on the cause. In children, the most frequent therapies are adenotonsillectomy or orthodontic therapies, specifically maxillary expansion
Redefine the Anterior Limit of the Dentition in Case of Functional Genioplasty: A Clinical Protocol
No full textObjectives: The purpose of this paper is to discuss the indications for “functional” genioplasty, as described by J. Delaire, and to analyze the implications of this surgical procedure on the choices the orthodontist must make regarding orthodontic treatment (extractions, anchorage, mechanics, etc.). In fact, this surgery modifies the position of the pogonion, the inferior reference point of the Apogonion line, which is fundamental for a correct calculation of spaces. Introduction: “Functional” genioplasty was first described by J. Delaire in 1983. This surgical procedure is indicated for individuals with Class II highangle malocclusion. The purpose of this procedure is not only to improve the aesthetics of patients with long, retruded chins, but also to promote labial competence by reducing the lower facial height. “Functional” genioplasty modifies both the labio-lingual neuromuscular balance and skeletal structure and, with it, some important cephalometric points and planes: Menton, Gnathion and pogonion, mandibular plane, facial axis, facial plane and A-Pogonion line. The orthodontist should carefully analyze these changes when evaluating treatment planning, especially when extractions are indicated and a new A-Pogonion line is to be drawn in the V.T.O (Visual Treatment Objectives). Materials and methods: The possibility of correcting a long, retruded chin by functional genioplasty and the reliability of cephalometric reevaluation with the described method are presented on a typical clinical case treated. The authors suggest specific timing for the orthodontic and surgical approach to high-angle Class II patients to achieve the best results. Results: The patient should undergo genioplasty as soon as the lower canines are erupted. Then it is important to wait 12–18 months to allow the improved labial competence to have an effect on the front dentition. Only at this point will it be possible to calculate orthodontic movements according to the new A-Pogonion line. Conclusions: “Functional” genioplasty is a low-impact, low-risk, and welltolerated surgical procedure. It corrects both neuromuscular and skeletal abnor- malities. However, the orthodontist must carefully consider these changes be- cause of the new orientation of the A-pogonion line
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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