Andrea Mapelli

Mandibular kinematics and masticatory muscles EMG in patients with short lasting TMD of mild-moderate severity

Mandibular kinematic and standardized surface electromyography (sEMG) characteristics of masticatory muscles of subjects with short lasting TMD of mild-moderate severity were examined. Volunteers were submitted to clinical examination and questionnaire of severity. Ten subjects with TMD (age 27.3years, SD 7.8) and 10 control subjects without TMD, matched by age, were selected. Mandibular movements were recorded during free maximum mouth opening and closing (O-C) and unilateral, left and right, gum chewing. sEMG of the masseter and temporal muscles was performed during maximum teeth clenching either on cotton rolls or in intercuspal position, and during gum chewing. sEMG indices were obtained. Subjects with TMD, relative to control subjects, had lower relative mandibular rotation at the end of mouth opening, larger mean number of intersection between interincisal O-C paths during mastication and smaller asymmetry between working and balancing side, with participation beyond the expected of the contralateral muscles (P<0.05, t-test). Overall, TMD subjects showed similarities with the control subjects in several kinematic parameters and the EMG indices of the static test, although some changes in the mastication were observed.

Translation and rotation movements of the mandible during mouth opening and closing

To assess the relative contribution of rotation and translation of the temporomandibular condyle‐disc assembly during opening and closing movements, free movements of maximum mouth opening and closing were recorded in healthy subjects (12 men, 14 women) using an optoelectronic three‐dimensional motion analyzer. For each subject, the displacement of the lower interincisal point, the path of the condylar reference point, the degree of rotation around the three orthogonal rotational axes, and the relative contribution of translation and rotation were calculated during all movement of mouth opening and closing. The distance covered by the interincisor point and the rotational angle about the transverse axis at maximum mouth opening were larger in men than in women, but the difference cancelled after correcting for mandibular radius in the sagittal plane; mandibular rotation was always larger than translation, but never approaching 100%; opening and closing translations were similar within sex, but their paths were longer in men than in women (P < 0.05); rotational angles around vertical and sagittal axes were negligible; the linear correlation between maximum mandibular opening and condylar translation was minor and not significant. In normal subjects, mouth opening and closing as modeled at the interincisor point was determined more by mandibular rotation than by translation, but in no occasion a pure rotation was found. The percentage rotation was not identical during mouth opening and closing; female and male paths were not totally coincident; no correlation between maximum mandibular opening and condylar translation was found. Clin. Anat. 22:311–318, 2009.

Validation of a protocol for the estimation of three-dimensional body center of mass kinematics in sport

Since strictly related to balance and stability control, body center of mass (CoM) kinematics is a relevant quantity in sport surveys. Many methods have been proposed to estimate CoM displacement. Among them, segmental method appears to be suitable to investigate CoM kinematics in sport: human body is assumed as a system of rigid bodies, hence the whole-body CoM is calculated as the weighted average of the CoM of each segment. The number of landmarks represents a crucial choice in the protocol design process: one have to find the proper compromise between accuracy and invasivity. In this study, using a motion analysis system, a protocol based upon the segmental method is validated, adopting an anatomical model comprising 14 landmarks. Two sets of experiments were conducted. Firstly, our protocol was compared to the ground reaction force method (GRF), accounted as a standard in CoM estimation. In the second experiment, we investigated the aerial phase typical of many disciplines, comparing our protocol with: (1) an absolute reference, the parabolic regression of the vertical CoM trajectory during the time of flight; (2) two common approaches to estimate CoM kinematics in gait, known as sacrum and reconstructed pelvis methods. Recognized accuracy indexes proved that the results obtained were comparable to the GRF; what is more, during the aerial phases our protocol showed to be significantly more accurate than the two other methods. The protocol assessed can therefore be adopted as a reliable tool for CoM kinematics estimation in further sport researches.

Facial movement before and after masseteric-facial nerves anastomosis: A three-dimensional optoelectronic pilot study ☆

To quantify the effects of facial palsy reanimation, 14 patients aged 17-66 years were analysed. All patients had unilateral facial paralysis, and were candidates for surgical masseteric to facial nerve anastomosis. Two patient groups were measured: seven patients were waiting for surgery, the other seven patients had already been submitted to surgery, and had regained facial mimicry. Each patient performed three facial animations: brow raise; free smile; lip purse. These were recorded using an optoelectronic motion analyser. The three-dimensional coordinates of facial landmarks were obtained, their movements were computed, and asymmetry indices calculated (differential movements between the two hemi-faces: healthy and paretic/rehabilitated). Before surgery, mobility was larger in the healthy than in the paretic side; after surgery, the differences were reduced (brow raise and lip purse), or even reversed (smile). Before surgery, lip purse was performed with significant labial asymmetry (p=0.042; larger healthy side movement). After surgery, asymmetry indices reduced. Total labial asymmetry during smiling was significantly different from 0 before surgery (p=0.018, larger healthy side movement). After surgery, all asymmetry indices became non-significant. Before surgery the lateral displacements of all labial landmarks were towards the healthy side, while they normalized after surgery.

Three-dimensional mandibular motion after closed and open reduction of unilateral mandibular condylar process fractures.

OBJECTIVE To detect the changes in 3D mandibular motion after two types of condylar fracture therapies. MATERIALS AND METHODS Using a 3D motion analyzer, free mandibular border movements were recorded in 21 patients successfully treated for unilateral fractures of the mandibular condylar process (nine patients: open reduction, rigid internal fixation, and functional treatment; 12 patients: closed reduction and functional treatment; follow-up: 6-66 months), and in 25 control subjects. RESULTS No differences were found among the groups at maximum mouth opening (MO), protrusion and in lateral excursions. During opening, the patients had a larger maximal deviation to the fractured side than the controls (controls 2.3 mm, open treatment 3.9 mm, closed treatment 4.2 mm; Kruskal-Wallis test, p=0.014; closed treatment vs. controls, p=0.004), with a larger coronal plane angle (controls 2.4°, open treatment 3.6°, closed treatment 4.4°; p=0.016; closed treatment vs. controls, p=0.013). In the closed treatment patients, a longer follow-up was related to increased maximum MO (p=0.04), sagittal plane angle (p=0.03), and reduced lateral mandibular deviation during MO (p=0.03). CONCLUSION Mandibular condylar fractures can recover good function; some kinematic variables of mandibular motion were more similar to the norm in the open treatment patients than in closed treatment patients.

EMG spectral characteristics of masticatory muscles and upper trapezius during maximum voluntary teeth clenching.

To assess the surface electromyographic spectral characteristics of masticatory and neck muscles during the performance of maximum voluntary clench (MVC) tasks, 29 healthy young adults (15 men, 14 women, mean age 22years) were examined. Electromyography of masseter, temporalis and upper trapezius muscles was performed during 5-s MVCs either on cotton rolls or in intercuspal position. Using a fast Fourier transform, the median power frequency (MPF) was obtained for the first and last seconds of clench, and compared between sexes, muscles, sides, tests and time intervals using ANOVAs. On average, the MPFs did not differ between sexes or sides (p>0.05), but significant effects of muscle (MPF temporalis larger than masseter, larger than trapezius muscles), test (larger MPFs when clenching in intercuspal position than when clenching on cotton rolls) and time (larger MPFs in the first than in the fifth second of clench) were found. In conclusion, a set of data to characterize the sEMG spectral characteristics of jaw and neck muscles in young adult subjects performing MVC tasks currently in use within the dental field was obtained. Reference values may assist in the assessment of patients with alterations in the cranio-cervical-mandibular system.

Mandibular kinematics after orthognathic surgical treatment. A pilot study

We recorded three-dimensional mandibular movements, while the mouth was being opened and closed, using an optoelectronic motion analyser in 14 patients (5 skeletal Class II, 9 skeletal Class III) who were being assessed 7-49 months after orthognathic operations, and in 44 healthy subjects. All 14 patients had satisfactory healing on clinical examination, and function had been restored. Mandibular movement was divided into its rotational and translational components. On maximum mouth opening, the patients had significantly less total displacement of the mandibular interincisor point (p=0.05), and more mandibular movement that was explained by pure condylar rotation (p=0.006), than control subjects. There was no significant relation between maximum mouth opening and percentage rotation. While mandibular motion was well restored clinically by orthognathic surgery, the kinematics of the joint were modified. Larger studies and longitudinal investigations are necessary to appreciate the clinical relevance of the variations in condylar rotational and translational components.

Effect of Leg Dominance on The Center-of-Mass Kinematics During an Inside-of-the-Foot Kick in Amateur Soccer Players

Abstract Soccer kicking kinematics has received wide interest in literature. However, while the instep-kick has been broadly studied, only few researchers investigated the inside-of-the-foot kick, which is one of the most frequently performed techniques during games. In particular, little knowledge is available about differences in kinematics when kicking with the preferred and non-preferred leg. A motion analysis system recorded the three-dimensional coordinates of reflective markers placed upon the body of nine amateur soccer players (23.0 ± 2.1 years, BMI 22.2 ± 2.6 kg/m2), who performed 30 pass-kicks each, 15 with the preferred and 15 with the non-preferred leg. We investigated skill kinematics while maintaining a perspective on the complete picture of movement, looking for laterality related differences. The main focus was laid on: anatomical angles, contribution of upper limbs in kick biomechanics, kinematics of the body Center of Mass (CoM), which describes the whole body movement and is related to balance and stability. When kicking with the preferred leg, CoM displacement during the ground-support phase was 13% higher (p<0.001), normalized CoM height was 1.3% lower (p<0.001) and CoM velocity 10% higher (p<0.01); foot and shank velocities were about 5% higher (p<0.01); arms were more abducted (p<0.01); shoulders were rotated more towards the target (p<0.01, 6° mean orientation difference). We concluded that differences in motor control between preferred and non-preferred leg kicks exist, particularly in the movement velocity and upper body kinematics. Coaches can use these results to provide effective instructions to players in the learning process, moving their focus on kicking speed and upper body behavior

Quantification of facial movements by optical instruments: surface laser scanning and optoelectronic three-dimensional motion analyzer.

AbstractThe objective of this study was to assess the accuracy of displacements of tracing landmarks in standardized facial movements. Forty healthy persons were evaluated in 2 different groups (20 men and 20 women, aged 18–30 years) with optoelectronic motion analyzer and surface laser scanning. The displacements of tracing landmarks in brow lift and smile were calculated, and the 2 methods (optoelectronic motion analyzer and surface laser scanning) were compared in healthy persons. Side-related differences were found in the tracing landmark (superciliare) during brow lift movements between both methods (the largest movements were found on the right side, P = 0.044), whereas in smile movements the tracing landmark cheilion did not show significant differences between the 2 sides.In both movements, the differences of the tracing landmark displacements between the 2 systems and sexes were on average less than 2 mm, without statistically significant differences (P > 0.05). In conclusion, normal young adult men and women had similar standardized facial movements. The 2 analyzed movements can be measured by both optical instruments with comparable results.

Stair Ascent and Descent in Assessing Donor-Site Morbidity Following Osteocutaneous Free Fibula Transfer: A Preliminary Study

PURPOSE The aim of this study was to investigate gait kinematic parameters during stair ascent and descent after fibula free flap removal for facial reconstruction. MATERIALS AND METHODS Eight patients who underwent facial reconstruction with fibula free flap removal ascended and descended 3 standard steps. Their movements were recorded by a motion analyzer; gait kinematic parameters were obtained and compared with those calculated in 8 control subjects. RESULTS Stride time, percentage of swing, and support phases did not differ among healthy and operated limbs and control subjects (Kruskal-Wallis, P > .05). No significant differences were found for hip and knee movements, pelvis rotation and tilt, and body center of mass displacements. During stair descent, the patients had significantly larger pelvis inclinations than the control subjects (P < .05). CONCLUSIONS No functional limitations during stair performance were found. The only significant difference could indicate a minor control of the pelvis and should be used to define specific rehabilitative interventions.