69 research outputs found
Glenoid fossa position in Class II malocclusion associated with mandibular retrusion
Abstract
Objective: To assess the position of the glenoid fossa in subjects with Class II malocclusion associated with mandibular retrusion and normal mandibular size in the mixed dentition.
Materials and Methods: A sample of 30 subjects (16 male, 14 female), age 9 years ± 6 months, with skeletal and dental Class II malocclusion associated with mandibular retrusion, normal skeletal vertical relationships, and normal mandibular dimensions, was compared with a matched group of 37 subjects (18 male, 19 female) with skeletal and dental Class I relationships. The comparisons between the Class II group and the control group on the cephalometric measures for the assessment of glenoid fossa position were performed by means of a nonparametric test for independent samples (Mann-Whitney U-test, P < .05).
Results: Subjects with Class II malocclusion presented with a significantly more distal position of the glenoid fossa, when compared with the control group as measured by means of three parameters (GF-S on FH, GF-Ptm on FH, and GF-FMN).
Conclusions: A posteriorly displaced glenoid fossa is a possible diagnostic feature of Class II malocclusion associated with mandibular retrusion. An effective cephalometric measurement to evaluate glenoid fossa position is the distance from the glenoid fossa to the frontomaxillonasal suture (GF-FMN)
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Pharmacotherapy in patients with epilepsy and psychosis.
The recognition and treatment of psychosis in persons with epilepsy (PWE) is recommended with the apparent dilemma between treating psychosis and opening the possibility of exacerbating seizures. The pooled prevalence estimate of psychosis in PWE is 5.6%. It has been proposed that a 'two hit' model, requiring both aberrant limbic activity and impaired frontal control, may account for the wide range of clinical phenotypes. The role of antiepileptic drugs in psychosis in PWE remains unclear. Alternating psychosis, the clinical phenomenon of a reciprocal relationship between psychosis and seizures, is unlikely to be an exclusively antiepileptic drug-specific phenomenon but rather, linked to the neurobiological mechanisms underlying seizure control. Reevaluation of antiepileptic treatment, including the agent/s being used and degree of epileptic seizure control is recommended. The authors found very few controlled studies to inform evidence-based treatment of psychosis in PWE. However, antipsychotics and benzodiazepines are recommended as the symptomatic clinical treatments of choice for postictal and brief interictal psychoses. The general principle of early symptomatic treatment of psychotic symptoms applies in epilepsy-related psychoses, as for primary psychotic disorders. In the authors' experience, low doses of antipsychotic medications do not significantly increase clinical risk of seizures in PWE being concurrently treated with an efficacious antiepileptic regimen
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The polygenic nature of telomere length and the anti-ageing properties of lithium
Telomere length is a promising biomarker for age-related disease and a potential anti-ageing drug target. Here, we study the genetic architecture of telomere length and the repositioning potential of lithium as an anti-ageing medication. LD score regression applied to the largest telomere length genome-wide association study to-date, revealed SNP-chip heritability estimates of 7.29%, with polygenic risk scoring capturing 4.4% of the variance in telomere length in an independent cohort (p = 6.17 × 10-5). Gene-enrichment analysis identified 13 genes associated with telomere length, with the most significant being the leucine rich repeat gene, LRRC34 (p = 3.69 × 10-18). In the context of lithium, we confirm that chronic use in a sample of 384 bipolar disorder patients is associated with longer telomeres (p = 0.03). As complementary evidence, we studied three orthologs of telomere length regulators in a Caenorhabditis elegans model of lithium-induced extended longevity and found all transcripts to be affected post-treatment (p  0.05). Consequently, this suggests that lithium may be catalysing the activity of endogenous mechanisms that promote telomere lengthening, whereby its efficacy eventually becomes limited by each individual's inherent telomere maintenance capabilities. Our work indicates a potential use of polygenic risk scoring for the prediction of adult telomere length and consequently lithium's anti-ageing efficacy
History of functional therapy: From monobloc to twin-blocks appliances [Evoluzione storica e clinica della terapia funzionale: Dal monoblocco al bi-placca]
The aim of this study is to follow the historical development of functional appliances for the correction of skeletal Class II malocclusions, starting from different types of monobloc to the contemporary twin-blocks appliances. The Authors analysed theories and appliances proposed by many Authors who contributed to enrich functional "philosophy". The idea to split Andresen's monobloc into two removable plates, maintaining the advancement construction bite, has led to the development of the most used contemporary appliances: the Bite-jumping by Sander and the Twin-blocks by Clark. In these appliances any potential benefit of functional therapy is maintained, particularly as far as mandibular advancement and growth are concerned. The advantages of using a double-blocks appliance with respect to a monobloc consist of greater comfort for the patient, with a consequent greater compliance, of the possibility to add auxiliary elements and finally of a better control of the dentoalveolar effects during a functional treatment, with a reduced lower teeth mesial migration
An analysis of the corrective contribution in activator treatment
This retrospective study (1) cephalometrically investigates the effectiveness of activator therapy, (2) evaluates the contribution of skeletal growth in the self-correction of the Class II malocclusion, and (3) analyzes separately the dental and skeletal responses to activator treatment and the differences between the incisor and molar areas. The subjects, all in the mixed dentition, were selected from a single center and were divided into a group of 40 Class II patients treated with an activator and an untreated group of 30 Class II patients. Dentoskeletal changes that occurred were compared on lateral cephalograms taken before the treatment/observation period and after 21 months (standard deviation, three months). When the activator patients were compared with the untreated control subjects, therapy promoted a combination of skeletal and dental changes that led to an improvement of the sagittal discrepancy. Other changes observed in the untreated Class II subjects did not bring about a correction of the malocclusion. An analysis of the corrective contributions in activator therapy in the posterior area showed that the orthopedic effects were greater than the dental effects in correcting the posterior occlusal relationship. In the anterior area of the arch, although both the skeletal and dental changes were favorable toward the sagittal correction, the skeletal contribution was greater than the dental contribution. In general, the skeletal contribution (140%) exceeded the dental correction (60%), and the mandibular changes (73%) exceeded the maxillary contribution (27%) both in the anterior and posterior regions
An analysis of the corrective contribution in activator treatment
This retrospective study (1) cephalometrically investigates the effectiveness of activator therapy, (2) evaluates the contribution of skeletal growth in the self-correction of the Class II malocclusion, and (3) analyzes separately the dental and skeletal responses to activator treatment and the differences between the incisor and molar areas. The subjects, all in the mixed dentition, were selected from a single center and were divided into a group of 40 Class II patients treated with an activator and an untreated group of 30 Class II patients. Dentoskeletal changes that occurred were compared on lateral cephalograms taken before the treatment/observation period and after 21 months (standard deviation, three months). When the activator patients were compared with the untreated control subjects, therapy promoted a combination of skeletal and dental changes that led to an improvement of the sagittal discrepancy. Other changes observed in the untreated Class II subjects did not bring about a correction of the malocclusion. An analysis of the corrective contributions in activator therapy in the posterior area showed that the orthopedic effects were greater than the dental effects in correcting the posterior occlusal relationship. In the anterior area of the arch, although both the skeletal and dental changes were favorable toward the sagittal correction, the skeletal contribution was greater than the dental contribution. In general, the skeletal contribution (140%) exceeded the dental correction (60%), and the mandibular changes (73%) exceeded the maxillary contribution (27%) both in the anterior and posterior regions
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