A 3-year follow-up study of all-ceramic single and multiple crowns performed in a private practice: a prospective case series

OBJECTIVES: Zirconia-based prostheses are commonly used for aesthetic crown and fixed restorations, although follow-up data are limited, especially for implant-supported crowns. The aim of this study was to evaluate the threeyear clinical results of the installation of 463 zirconia core crowns by a general dental private practice. METHODS: This study followed 142 patients (69 men and 73 women; aged 28-82 years) who had received 248 single crowns (202 tooth-supported, 36 implant-supported) and 225 multiple units of up to six elements (81 toothsupported, 144 implant-supported). Clinical events, including fracture and loss of retention, secondary caries, and marginal integrity, were recorded. The overall failure rate was computed for the fractured and lost prostheses. Aesthetic, functional, and biological properties were rated, and patient satisfaction was investigated. RESULTS: During the three-year follow-up period, four patients were lost from the study (18 crowns, 4% of the total crowns). Three of the zirconia prostheses suffered fractures in more than three units (11 crowns; one- vs. three-year follow-up, p,0.05, Wilcoxon signed-rank test), and the cumulative prosthesis survival rate was 98.2%. Twelve units lost retention and were re-cemented, and no secondary caries of the abutment teeth were reported. The aesthetic, functional, and biological properties were generally well-rated, and there were no differences between tooth- and implant-supported crowns. The lowest scores were given regarding the anatomical form of the crowns, as some minor chipping was reported. Relatively low scores were also given for the periodontal response and the adjacent mucosa. Overall, patient satisfaction was high. CONCLUSIONS: At the three-year follow-up, the zirconia-core crowns appeared to be an effective clinical solution as they had favorable aesthetic and functional properties. Only the marginal fit of the prostheses should be improved upon

PRINCIPAL COMPONENTS OF THE 180°-TURN WITH THE BALL KINEMATICS IN YOUTH SOCCER PLAYERS

The interpretation of parameters extracted from sophisticated sport-specific techniques is not always straightforward. This is the case of the 180° change of direction with the ball in soccer. The 180°-turn performance of ten Under-13, sub-elite soccer players was recorded by means of a motion capture system. Principal Component Analysis (PCA) was applied to a set of 21 anthropometrics and kinematic variables including center of mass related quantities and joints range of motion. The first three principal components, explaining 61% of the overall variance, were retained and discussed. PCA unveiled the relevant structure of the dataset, describing both movement speed and amplitude issues, and the relationship between body size and the change of direction ability

A photographic system for the three-dimensional study of facial morphology.

Abstract Objectives: To test whether digital photographs supported by three-dimensional (3D) software are suitable for measuring the facial soft tissues of healthy subjects as compared with data obtained by a certified 3D computerized electromagnetic digitizer. Materials and Methods: Three-dimensional soft tissue facial landmarks were obtained from the faces of 15 healthy young adults, using a 3D computerized electromagnetic digitizer and a new low-cost photogrammetry system. Twelve linear and 18 angular measurements were computed. Errors between methods and repeatability of the new method were calculated. Results: Systematic errors between methods were found for only two distances and three angles (paired t-test, P < .05). The mean absolute differences between methods were always lower than 3 mm and 3 degrees. Repeated digitization of photographs showed that the method was repeatable (no systematic differences; random errors lower than 1.6 mm and 3 degrees). Repeated sets of photographs showed random errors of up to 5.3 mm and 5.6 degrees, without systematic biases. Conclusion: The 3D photogrammetry system can provide reliable facial measurements. The method is relatively fast and requires only inexpensive equipment. It is simple to use for private practice, research, or other practice

FATIGUE ALTERS THE BIOMECHANICS OF TURNS WHILE RUNNING

This study identified the effects of fatigue on lower limb kinematics while running with repeated 180°-turns. An increased stiffness of the pivoting limb was observed in terms of a reduction of hip and knee flexion angles, and an increase of hip abduction and internal rotation. We concluded that muscle fatigue can trigger a sequence of adaptations that were previously found to expose the athlete to an increasing risk of ligament injury. These results expand the base of evidence for the development of field-based prevention programs

Longitudinal effects of rapid maxillary expansion on masticatory muscles activity

To investigate the modifications induced by rapid maxillary expansion (RME) on the electromyographic (EMG) activities of the anterior temporal and superficial masseter muscles, in patients without pre-treatment EMG alterations. Twenty-one patients with unilateral posterior cross-bite selected from the orthodontic department of the University of L?Aquila (Italy), were enrolled. There was no control group in this study since each subject acted as a control of her/himself. Two surface EMG recordings were taken: T0 (before RME) and at T1 (3 month after the end of expansion). To verify the neuromuscular equilibrium, the EMG activities of both right and left masseter and anterior temporal muscles were recorded during a test of maximum clench. EMG indexes were compared by paired Student?s t-test. In both occasions, all indices showed a good symmetry between the right and left side masticatory muscles. No statistically significant differences were found between the two recordings. In children without pre-treatment EMG alterations, no variations in standardized muscular activity after RME were found. The treatment did not alter the equilibrium of the masseter and temporal muscles

Cephalometric measurements performed on CBCT and reconstructed lateral cephalograms: a cross-sectional study providing a quantitative approach of differences and bias

Background: Cephalometric analysis is traditionally performed on skull lateral teleradiographs for orthodontic diagnosis and treatment planning. However, the skull flattened over a 2D film presents projection distortions and superimpositions to various extents depending on landmarks relative position. When a CBCT scan is indicated for mixed reasons, cephalometric assessments can be performed directly on CBCT scans with a distortion free procedure. The aim of the present study is to compare these two methods for orthodontic cephalometry. Methods: 114 CBCTs were selected, reconstructed lateral cephalometries were obtained by lateral radiographic projection of the entire volume from the right and left sides. 2D and 3D cephalometric tracings were performed. Since paired t-tests between left and right-side measurements found no statistically significant differences, mean values between sides were considered for both 2D and 3D values. The following measurements were evaluated: PNS-A; S-N; N-Me; N-ANS; ANS-Me; Go-Me; Go-S; Go-Co; SNA, SNB, ANB; BaŜN; S-N^PNS-ANS; PNS-ANS^Go-Me; S-N^Go-Me. Intraclass correlation coefficients, paired t-test, correlation coefficient and Bland-Altman analysis were performed to compare these techniques. Results: The values of intra- and inter-rater ICC showed excellent repeatability and reliability: the average (± SD) intraobserver ICCs were 0.98 (± 0.01) and 0.97(± 0.01) for CBCT and RLCs, respectively; Inter-rater reliability resulted in an average ICC (± SD) of 0.98 (± 0.01) for CBCT and 0.94 (± 0.03) for RLC. The paired t-tests between CBCT and reconstructed lateral cephalograms revealed that Go-Me, Go-S, PNS-ANS^Go-Me and S-N^Go-Me measurements were statistically different between the two modalities. All the evaluated sets of measurements showed strong positive correlation; the bias and ranges for the 95% Limits of Agreement showed higher levels of agreement between the two modalities for unpaired measurements with respect to bilateral ones. Conclusion: The cephalometric measurements laying on the mid-sagittal plane can be evaluated on CBCT and used for orthodontic diagnosis as they do not show statistically significant differences with those measured on 2D lateral cephalograms. For measurements that are not in the mid-sagittal plane, the future development of specific algorithms for distortion correction could help clinicians deduct all the information needed for orthodontic diagnosis from the CBCT scan

Effects of the functional orthopaedic therapy on masticatory muscles activity

The purpose of this study was to examine surface electromyographic (sEMG) activity of masticatory muscles before and after functional orthopaedic therapy with Sander appliance. Ten adolescents (5 girls, 5 boys) with an Angle Class II, division I malocclusion, 9-13 years old, were submitted to sEMG before and after functional orthopaedic therapy. To verify the neuromuscular equilibrium, the standardized EMG activities of right and left masseter and anterior temporal muscles were recorded during maximum voluntary clench, and analysed calculating: POC (index of the symmetric distribution of the muscular activity determined by the occlusion); TC (index of presence of mandibular torque) and Ac (index suggesting the position of occlusal barycentre). The total muscular activity was also calculated. Pre- and post- functional therapy data were compared with Wilcoxon Signed-Rank Test. Before treatment, all subjects had a good neuromuscular equilibrium, which was not altered by treatment. sEMG evaluations allow to quantify the impact of occlusion on masticatory muscle activity and to control that the functional orthopaedic therapy maintain a good muscular coordination

DECELERATION COUNTS: ESTIMATING THE ENERGY COST OF SHUlTLE RUNNING FROM MECHANICAL WORK

To estimate the energetic requirements of 5-m shuttle running based on kinematic data, we devised a modified version of existing models for the estimation of the energy cost of gait. In our approach, negative/eccentric work during deceleration phases was added to positive/concentric work in propulsive phases. Ten subjects performed two 5-rnin trials at 50% and 75% of their maximal aerobic speed. The metabolic cost estimated from 30 kinematics was compared to that measured by a portable metabolimeter. The estimation error was 1.2 J/kg/s (7.3%): results encourage to apply this method for the estimation of the workload in sports involving frequent turns and changes of direction

A KINEMATICALLY BASED ALGORITHM TO ESTIMATE THE ENERGY COST OF VARIABLE-SPEED SHUTTLE RUNNING

Changes of direction (CoDs) have a high metabolic and mechanical impact in field and court team sports, but the estimation of the associated workload is still inaccurate. The aim of this study is to establish a kinematic-based algorithm to determine the energy cost of running at variable speed with frequent 180° CoDs. Kinematic and metabolic data were simultaneously collected during 5-minutes 5+5 m shuttle run tests. Mechanical work computation was split into positive (eccentric) and negative (concentric) contributions. When compared to the actual energy cost, the estimation algorithm returned an error of 5%. This model constitutes the theoretical basis to extend the model from the laboratory to the field, obtaining an accurate measure of the workload of training and matches

Is Orthodontic Treatment with Microperforations Worth It? A Scoping Review

Malformations of teeth and dental arches can produce functional modifications intermingled with esthetic alterations. Children’s rehabilitation may be long, requiring multiple interventions. One of the main challenges of contemporary orthodontics is to reduce treatment time by accelerating orthodontic tooth movements. Among the currently used methods, micro-osteoperforations (MOPs) are flapless, minimally invasive perforations that induce a local trauma to the bone, increase healing capacity, and accelerate dental movements. The use of MOPs in orthodontics is spreading but there are no definite and recognized protocols for their application. This scoping review collected the available evidence in the effect of MOPs during orthodontic therapy as compared to current treatments, to summarize the evidence. The guidelines proposed by PRISMA-ScR were followed: original clinical studies carried out from 2010 to 2021 were retrieved by medical databases combining the terms “micro-osteoperforations” and “accelerated orthodontic tooth movement”. From a total of 965 articles, nine were finally selected. The studies' aims, designs, methods, measurements, outcomes, and main findings were very heterogenous, with a duration ranging from 4 weeks to 7 months. This included only Class I malocclusion to any malocclusion. It assessed the effects of MOPs coupled with a variety of orthodontic mechanics on either the retraction of maxillary canines, the distalization of maxillary molars, or the modifications on premolar roots. Mostly, variations in the number, location, and timing of MOPs impeded a global assessment. Overall, most of the studies (six out of nine) reported moderately useful effects of MOPs, one was negative, and only two found significant advantages of MOPs over conventional treatment. The review synthesized the available evidence about MOP applications in orthodontics and identified some important gaps in knowledge that could be starting points for a systematic review of the literature. In conclusion, even if MOPs can accelerate tooth movements, the variety of aims and methods of the published research prevents suggestion of their widespread use