Search results for "Significance"
showing 10 items of 532 documents
Esthetic Assessment of the Effect of Gingival Exposure in the Smile of Patients with Unilateral and Bilateral Maxillary Incisor Agenesis
2014
Purpose: The aim of this study was to determine the dental esthetic perception of the smile of patients with maxillary lateral incisor agenesis (MLIA); the perceptions were examined pre- and post-treatment. Esthetic determinations were made with regard to the gingival exposure in the patients’ smile by orthodontists, general dentists, and laypersons. Materials and Methods: Three hundred eighty one people (80 orthodontists, 181 general dentists, 120 laypersons) rated the attractiveness of the smile in four cases before and after treatment, comprising two cases with unilateral MLIA and contralateral microdontia and two with bilateral MLIA. For each case, the buccal photograph was adjusted usi…
Prevalence and characterization of maxillary sinus septa in a brazilian population
2019
Background The aim of this study was to assess the anatomic aspects of the maxillary sinus septa, by means of computed tomography images, in a Brazilian population. The results might be of clinical significance in sinus lift surgery planning. Material and methods In the study, 123 computed tomographs obtained from a private radiology clinic were used. They were analyzed by a single, trained and calibrated observer in order to evaluate the presence, quantity, localizations, dimensions, orientations and different characteristics in dentate, partially edentulous and completely edentulous individuals of the sinus septa. Results Of the individuals analyzed, 26% had a septum in the maxillary sinu…
The effect of orthodontic bracket pad shape on shear bond strength, an in vitro study on human enamel
2018
Background To evaluate the effect of bracket pad shape on shear bond strength (SBS) of orthodontic brackets bonded to human enamel. Material and Methods One hundred and five extracted human maxillary permanent molars were divided into 7 groups of 15 specimens per group (n=15). Each group of teeth was bonded with 6 different shaped WildSmiles® brackets (Star, Heart, Soccer ball, Football, Flower, and Diamond) and GAC® rectangle shaped brackets. Shear debonding force was measured with an Instron universal testing machine using a knife-edged chisel 24 hours after initial bonding. Descriptive statistics (mean, standard deviation, and range) for each bracket pad shape was calculated. Analysis of…
The effect of dental chair light exposure duration on shear bond strength of orthodontic brackets : an in vitro study
2018
Background The purpose of this study is to determine if the duration of exposure to the halogen overhead dental chair light has an effect on shear bond strength (SBS) of metal orthodontic brackets. Material and Methods One hundred twenty extracted human lower incisor teeth were divided into six groups (n=20/group). Each group was assigned a predetermined duration of exposure to the halogen dental chair light, set at a fixed distance, before being cured. Light exposure times of 0 minutes (Group 1-Control), 1 minute (Group 2), 2.5 minutes (Group 3), 5 minutes (Group 4), 10 minutes (Group 5), and 15 minutes (Group 6) were tested. Each tooth was subjected to an exclusion criteria examination, s…
Influence of Vertical Dimension of Occlusion on Peak Force During Handgrip Tests in Athletes
2018
Background: In contact sports, such as martial arts, protection from oral injuries is generally recommended. Several authors have focused on the effects of wearing such oral protective gear on sports performances and, in particular, occlusal devices. Although many studies have shown improvements in athletic performance, especially in maximal isometric strength, to date there is still no consensus on the issue. Objectives: The aim of our study was to evaluate differences in isometric handgrip before and after the application of an occlusal splint (OS) in martial arts athletes. Methods: A repeated measures within-subjects design was adopted for the study. Twenty-five young martial arts athlet…
Altered passive eruption (APE) : a little-known clinical situation
2010
Gummy smile constitutes a relatively frequent aesthetic alteration characterized by excessive exhibition of the gums during smiling movements of the upper lip. It is the result of an inadequate relation between the lower edge of the upper lip, the positioning of the anterosuperior teeth, the location of the upper jaw, and the gingival margin position with respect to the dental crown. Altered Passive Eruption (APE) is a clinical situation produced by excessive gum overlapping over the enamel limits, resulting in a short clinical crown appearance, that gives the sensation of hidden teeth. The term itself suggests the causal mechanism, i.e., failure in the passive phase of dental eruption, tho…
Distraction osteogenesis in dog with a tooth-borne device: Histological and histomorphometric analysis.
2019
Background The distraction osteogenesis (DO) is the biological process of new bone formation between the surfaces of bone segments gradually separated by incremental traction. However, the lack of solid experimental studies using the tooth-borne distractor does not allow comparing this technique with the classical procedures. This study aimed to establish the effect of two different activation protocols in new bone formation, with a new intraoral tooth-borne device for dog mandibular distraction osteogenesis. Material and methods Nine beagle dogs were split into 3 similar groups, Group A the control, Group B subjected to two daily activations of 0.5 mm and Group C subjected to a single dail…
Manipulating the alpha level cannot cure significance testing
2018
We argue that making accept/reject decisions on scientific hypotheses, including a recent call for changing the canonical alpha level from p = 0.05 to p = 0.005, is deleterious for the finding of new discoveries and the progress of science. Given that blanket and variable alpha levels both are problematic, it is sensible to dispense with significance testing altogether. There are alternatives that address study design and sample size much more directly than significance testing does; but none of the statistical tools should be taken as the new magic method giving clear-cut mechanical answers. Inference should not be based on single studies at all, but on cumulative evidence from multiple in…
Role of tumor-infiltrating lymphocytes in patients with solid tumors: Can a drop dig a stone?
2019
International audience; In recent years, multiple strategies for eliciting anti-tumor immunity have been developed in different clinical studies. Currently, immunotherapy was clinically validated as effective treatment option for many tumors such as melanoma, non-small cell lung cancer (NSCLC) and renal cell carcinoma (RCC). Some surface receptors of immune cells, called immune checkpoint receptors, may inhibit activity of proinflammatory lymphocytes, following binding with specific ligands. Cancer cells exploit these mechanisms to inactivate tumor-infiltrating lymphocytes (TILs) to escape from immunosurveillance. Among the different tumor-infiltrating immune cell populations, including leu…