Pietro Bracco

Publications of Pietro Bracco

• Expression of muscle-specific integrins in masseter muscle fibers during malocclusion disease.

  Authors: Giuseppina Cutroneo, Maria Grazia Piancino, Guglielmo Ramieri, Pietro Bracco, Giuseppe Vita, Gaetano Isola, Giovanna Vermiglio, Angelo Favaloro, Giuseppe Anastasi, Fabio Trimarchi

  International journal of molecular medicine. 04/2012;

  Integrins are heterodimeric cell surface membrane proteins linking the extracellular matrix to actin. α7B integrin is detected in proliferating and adult myofibers, whereas α7A plays a role inIntegrins are heterodimeric cell surface membrane proteins linking the extracellular matrix to actin. α7B integrin is detected in proliferating and adult myofibers, whereas α7A plays a role in regenerating muscle fibers with a minor function in mature muscle fibers. The expression levels of β1A appear to be very low, whereas β1D appears to be the predominant integrin form in mature muscle. Considering the important features of masseter muscle we have studied integrin expression in masseter muscle specimens of surgical patients with posterior right crossbite and comparing them to left side masseter muscle specimens. Our results showed that the expression of integrins was significantly lower in the crossbite side muscle. Furthermore, the most important finding is that β1A is clearly detectable in adult masseter muscle. This behavior could be due to the particular composition of masseter, since it contains hybrid fibers showing the capacity to modify the contractile properties to optimize the energy efficiency or the action of the muscle during contraction. Moreover, masseter is characterized by a high turnover of muscle fibers producing a regeneration process. This may indicate a longer time to heal, justifying the loss of β1D and the consequential increase of β1A. Thus, our data provide the first suggestion that integrins in masseter muscle play a key role regulating the functional activity of muscle and allowing the optimization of contractile forces.

• Chewing pattern and muscular activation in open bite patients.

  Authors: Maria Grazia Piancino, Gaetano Isola, Andrea Merlo, Domenico Dalessandri, Cesare Debernardi, Pietro Bracco

  Journal of electromyography and kinesiology : official journal of the International Society of Electrophysiological Kinesiology. 04/2012; 22(2):273-9.

  Different studies have indicated, in open bite patients, that masticatory muscles tend to generate a small maximum bite force and to show a reduced cross-sectional area with a lower EMG activity. TheDifferent studies have indicated, in open bite patients, that masticatory muscles tend to generate a small maximum bite force and to show a reduced cross-sectional area with a lower EMG activity. The aim of this study was to evaluate the kinematics parameters of the chewing cycles and the activation of masseters and anterior temporalis muscles of patients with anterior dental open bite malocclusion. There have been no previous reports evaluating both kinematic values and EMG activity of patients with anterior open bite during chewing. Fifty-two young patients (23 boys and 29 girls; mean age±SD 11.5±1.2 and 10.2±1.6years, respectively) with anterior open bite malocclusion and 21 subjects with normal occlusion were selected for the study. Kinematics parameters and surface electromyography (EMG) were simultaneously recorded during chewing a hard bolus with a kinesiograph K7-I Myotronics-Usa. The results showed a statistically significant difference between the open bite patients and the control group for a narrower chewing pattern, a shorter total and closing duration of the chewing pattern, a lower peak of both the anterior temporalis and the masseter of the bolus side. In this study, it has been observed that open bite patients, lacking the inputs from the anterior guidance, that are considered important information for establishing the motor scheme of the chewing pattern, show narrower chewing pattern, shorter lasting chewing cycles and lower muscular activation with respect to the control group.

• Ex vivo measurement reliability using two different cbct scanners for orthodontic purposes.

  Authors: Domenico Dalessandri, Pietro Bracco, Corrado Paganelli, Vicente Hernandez Soler, Conchita Martin

  The international journal of medical robotics + computer assisted surgery : MRCAS. 02/2012;

  BACKGROUND: There are many cone beam computed tomography (CBCT) scanners available on the market: detector technology, algorithm precision, and scanner settings influence image quality. The aim ofBACKGROUND: There are many cone beam computed tomography (CBCT) scanners available on the market: detector technology, algorithm precision, and scanner settings influence image quality. The aim of this study was to compare the accuracy of linear measurements made on images of the same sample obtained using two different CBCT scanners. METHODS: Twenty-eight linear measurements between orthodontic anatomical landmarks that were marked with gutta-percha points on a fresh sacrificed lamb head were taken three times. The head was scanned with two CBCT scanners using different scanning parameters. Digital Imaging and Communications in Medicine (DICOM) images were reconstructed and the same measurements were taken three times by the same operator. Measurements were repeated 4 months later by two operators. RESULTS: There was minimal, clinically significant difference between the measurements taken with the digital caliper or CBCT scanners, but there was no difference between the two different scanners. CONCLUSIONS: There is no clinically significant difference between these two scanners; a difference was found between the CBCT and real anatomical measurements in only a few cases. Copyright © 2012 John Wiley & Sons, Ltd.

• Reverse-sequencing chewing patterns evaluation in anterior versus posterior unilateral crossbite patients.

  Authors: Maria G Piancino, Elena Comino, Francesca Talpone, Teresa Vallelonga, Gianluigi Frongia, Pietro Bracco

  European journal of orthodontics. 09/2011;

  It is well established that patients with a unilateral posterior crossbite exhibit reverse-sequencing chewing patterns when chewing on the affected side. The aim of the study was to compare theIt is well established that patients with a unilateral posterior crossbite exhibit reverse-sequencing chewing patterns when chewing on the affected side. The aim of the study was to compare the prevalence of reverse-sequencing chewing cycles in patients with anterior versus posterior unilateral crossbite during chewing soft and hard boluses. Eighty-six children (39 boys, 47 girls) were included in the study: 26 (10.4 ± 2.7 years) with unilateral anterior crossbite, 43 (10.2 ± 4.2 years) with unilateral posterior crossbite, and 17 (10.6 ± 2 years) with normal occlusion were selected for the study. Mandibular movements were measured with a kinesiograph (K7, Myotronics Inc. Tukwila). The kinematic signals were analyzed using custom-made software. The results showed a low prevalence of reverse-sequencing chewing cycles in patients with anterior crossbite, without any significant difference between sides and with the control group, with both soft (P = 0.33) and hard (P = 0.29) bolus. The patients with posterior unilateral crossbite showed a significant higher prevalence of reverse-sequencing chewing cycles during chewing on the crossbite side with respect to the non-crossbite side (P < 0.001) and to the control group (P < 0.001). Comparing the patients with anterior versus posterior unilateral crossbite, a significant difference (P < 0.001) in the prevalence of reverse chewing cycles was demonstrated during chewing on the posterior crossbite side only with both soft and hard bolus. In conclusion, patients with anterior versus posterior unilateral crossbite show different functional characteristics depending on which dental region is involved.

• Clinical and instrumental evaluation of the temporomandibular joint before and after surgical correction of asymptomatic skeletal class III patients.

  Authors: Guglielmo Ramieri, Maria Grazia Piancino, Gianluigi Frongia, Giovanni Gerbino, Paolo Antonio Fontana, Cesare Debernardi, Pietro Bracco

  The Journal of craniofacial surgery. 03/2011; 22(2):527-31.

  The purpose of this prospective study was to evaluate the temporomandibular joint (TMJ) morphology, the disk position, and the TMJ symptoms before and after surgical-orthodontic correction ofThe purpose of this prospective study was to evaluate the temporomandibular joint (TMJ) morphology, the disk position, and the TMJ symptoms before and after surgical-orthodontic correction of skeletal class III malocclusion.Eleven adult patients were recruited to participate in this longitudinal study. Each patient received presurgical and postsurgical orthodontic treatment with fixed appliances. Six patients were corrected exclusively through mandibular setback, whereas 5 received combined mandibular setback and maxillary advancement. All patients were investigated before and 2 years after treatment through (1) clinical examination, (2) magnetic resonance imaging, and (3) Computerized axiography (CA).The incidence of clinical signs and symptoms was reduced 2 years after surgical-orthodontic treatment, the condyle-disk relationship and TMJ appearance at magnetic resonance imaging were unchanged, and CA showed a significant improvement of TMJ border movements.Mandibular setback surgery does not appear to alter the condyle-disk relationship, whereas correction of class III malocclusion seems to improve clinical and CA signs of TMJ function. Further controls and more long-term evaluation of these patients are necessary to assess the maintenance of these improvements in time.

• Advantages of cone beam computed tomography (CBCT) in the orthodontic treatment planning of cleidocranial dysplasia patients: a case report.

  Authors: Domenico Dalessandri, Laura Laffranchi, Ingrid Tonni, Francesca Zotti, Maria Grazia Piancino, Corrado Paganelli, Pietro Bracco

  Head & face medicine. 02/2011; 7:6.

  Our aim was to discuss, by presenting a case, the possibilities connected to the use of a CBCT exam in the dental evaluation of patients with Cleidocranial Dysplasia (CCD), an autosomal dominantOur aim was to discuss, by presenting a case, the possibilities connected to the use of a CBCT exam in the dental evaluation of patients with Cleidocranial Dysplasia (CCD), an autosomal dominant skeletal dysplasia with delayed exfoliation of deciduous and eruption of permanent teeth and multiple supernumeraries, often impacted. We think that CBCT in this patient was adequate to accurately evaluate impacted teeth position and anatomy, resulting thus useful both in the diagnostic process and in the treatment planning, with an important reduction in the radiation dose absorbed by the patient.

• Identification of a novel RUNX2 gene mutation in an Italian family with cleidocranial dysplasia.

  Authors: Cristiano Marchisella, Francesca Rolando, Lucia Anna Muscarella, Leopoldo Zelante, Pietro Bracco, Maria Rosaria Piemontese

  European journal of orthodontics. 12/2010; 33(5):498-502.

  Cleidocranial dysplasia (CCD) is a rare, well-defined skeletal disorder with autosomal dominant inheritance and complete penetrance. Although it involves the whole skeletal system, the main clinicalCleidocranial dysplasia (CCD) is a rare, well-defined skeletal disorder with autosomal dominant inheritance and complete penetrance. Although it involves the whole skeletal system, the main clinical manifestations of CCD are malformations of the skull and clavicles, which lead to a typical appearance of the face and shoulders. Dental aspects are particularly evident and often eruption difficulties are the first indication for the patient, who does not present any other problem. It has been established that insufficiency of the RUNX-related transcription factor, the core-binding factor alpha 1 (CBFA1) protein, causes CCD. This protein is essential in skeletal development by regulating osteoblast differentiation and chondrocyte maturation. CBFA1 protein is encoded by the RUNX2 gene located on chromosome 6p21. The molecular characterization of the novel RUNX2 gene mutation c.580 + 1G > A in an Italian family (a 27-year-old female, her 54-year-old mother and 24-year-old sister) affected by the typical CCD phenotype, which was proven to alter splicing of the RUNX2 messenger RNA, underscoring the contribution of novel altered splicing mechanism to the aetiology of this disease is presented.

• Evaluation of the stomatognathic system in patients with rheumatoid arthritis according to the research diagnostic criteria for temporomandibular disorders.

  Authors: Pietro Bracco, Cesare Debernardi, Maria Grazia Piancino, Maria Francesca Cirigliano, Giovanni Salvetti, Laura Bazzichi, Francesca De Feo, Mario Bosco

  Cranio : the journal of craniomandibular practice. 07/2010; 28(3):181-6.

  The aim of this study was to investigate the clinical features of stomatognathic dysfunction in patients with rheumatoid arthritis (RA). The study sample consisted of 40 patients with RA (34 female,The aim of this study was to investigate the clinical features of stomatognathic dysfunction in patients with rheumatoid arthritis (RA). The study sample consisted of 40 patients with RA (34 female, 6 male), mean age 44 years, recruited at the Rheumatology Division of the Department of Internal Medicine, University of Pisa, Italy. The inclusion criteria were diagnosis of RA according to the criteria of the American Rheumatism Association (ARA). In the study, 82.5% (n=33) of patients affected by RA satisfied at least the criteria of one diagnosis of temporomandibular disorders (TMD), according to the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD). The results are in agreement with the literature and the prevalence of such involvement ranges between 53% and 94% of patients. Several studies reported an involvement of the stomatognathic system in RA. In fact, RA can affect the temporomandibular joint as much as any other synovial joint. A more thorough analysis is required for a multidisciplinary approach to gnathological patients, including assessment by a rheumatologist. This issue and its epidemiologic relevance need further scientific research. Dentistry has a fundamental role in this process since patients who present with a systemic disease such as RA can be recognized and intercepted and referred to medical specialists, i.e., rheumatologists, to provide a diagnosis and therapy.

• Hemispheric prevalence during chewing in normal right-handed and left-handed subjects: a functional magnetic resonance imaging preliminary study.

  Authors: Pietro Bracco, Giuseppe Anastasi, Maria Grazia Piancino, Gianluigi Frongia, Demetrio Milardi, Angelo Favaloro, Placido Bramanti

  Cranio : the journal of craniomandibular practice. 04/2010; 28(2):114-21.

  This study evaluated the activation of different cortical areas during nondeliberate chewing of soft and hard boluses in five right-handed and five left-handed subjects with normal occlusion, toThis study evaluated the activation of different cortical areas during nondeliberate chewing of soft and hard boluses in five right-handed and five left-handed subjects with normal occlusion, to determine different hemispheric prevalences. The study was conducted with a functional Magnetic Resonance Imaging (1.5 T Magnetom Vision - Siemens Medical, Germany) using a head coil. The results showed that the most frequently activated areas were Brodmann's areas four and six in the primary motor and premotor cortex, the insula and Broca's area and, overall, showed greater activity of the cortical mastication area (CMA) in the right hemisphere for right-handed and in the left hemisphere for left-handed subjects.

• Slow or rapid palatal expansion for early treatment of unilateral posterior crossbite? Evaluation of the reverse chewing cycles correction.

  Authors: Maria G Piancino, Francesca Talpone, Teresa Vallelonga, Gianluigi Frongia, Cesare L Debernardi, Pietro Bracco

  Progress in orthodontics. 01/2010; 11(2):138-44.

  It is well established that patients with a unilateral posterior crossbite, when chewing on the affected side, show an increased frequency of reverse chewing cycles. It was hypothesized that theIt is well established that patients with a unilateral posterior crossbite, when chewing on the affected side, show an increased frequency of reverse chewing cycles. It was hypothesized that the correction of reverse cycles may be due to the characteristics of the therapy. The aim was to investigate the prevalence of reverse chewing patterns in children with unilateral posterior crossbite before and after treatment with Function Generating Bite (FGB). Twenty children, (9 boys, 11 girls; age, mean ± SD, 7.5 ± 1.1), 10 with a right and 10 with a left posterior unilateral crossbite were selected. Mandibular movements during chewing soft and hard boluses were measured with a kinesiograph (K7 -I, Myotronics Inc. Tukwila, Washington, USA). The results showed a significant difference when comparing the percentage of reverse chewing patterns, before and after therapy with FGB, during chewing on the crossbite side both with soft and hard bolus (p<0.0001). No significant differences were observed during chewing on the non-crossbite side. The results of this study confirmed that FGB corrects both the dental and functional asymmetries. Knowing that the rapid palatal expansion does not correct the masticatory function, it is of clinical relevance, for the orthodontists, the knowledge and the understanding of the functional outcomes with different therapies. The type of treatment and the biomechanics of the appliance used are of great importance for the correction of the reverse chewing cycles and for rebalancing the functional asymmetry of children with unilateral posterior crossbite.

• Muscular activation during reverse and non-reverse chewing cycles in unilateral posterior crossbite.

  Authors: Maria Grazia Piancino, Dario Farina, Francesca Talpone, Andrea Merlo, Pietro Bracco

  European journal of oral sciences. 05/2009; 117(2):122-8.

  The aim of this study was to characterize the kinematics and masseter muscle activation in unilateral posterior crossbite. Eighty-two children (8.6 +/- 1.3 yr of age) with unilateral posteriorThe aim of this study was to characterize the kinematics and masseter muscle activation in unilateral posterior crossbite. Eighty-two children (8.6 +/- 1.3 yr of age) with unilateral posterior crossbite and 12 children (8.9 +/- 0.6 yr of age) with normal occlusion were selected for the study. Electromyography (EMG) and kinematics were concurrently recorded during mastication of a soft bolus and a hard bolus. The percentage of reverse cycles in the group of patients was 59.0 +/- 33.1% (soft bolus) and 69.7 +/- 29.7% (hard bolus) when chewing on the crossbite side. When chewing on the non-affected side, the number of reverse cycles was 16.7 +/- 24.5% (soft bolus) and 16.7 +/- 22.3% (hard bolus). The reverse cycles on the crossbite side were narrower with respect to the cycles on the non-affected side. Although both types of cycles in patients resulted in lower EMG activity of the masseter of the crossbite side than of the contralateral masseter, the activity of the non-affected side was larger for reverse than for non-reverse cycles. It was concluded that when chewing on the crossbite side, the masseter activity is reduced on the mastication side (crossbite) and is unaltered (non-reverse cycles) or increased (reverse) on the non-affected side.

• Interleukin-1 gene cluster polymorphisms and gingival recessions after orthodontic treatment.

  Authors: Loredana Bergandi, Rachele Rubiano, Matteo Brunazzo, Elisabetta Alfieri, Paola Dal Masso, Giuseppe Cardaropoli, Pietro Bracco, Cesare Debernardi, Dario Ghigo

  Progress in orthodontics. 02/2008; 9(1):40-7.

  INTRODUCTION: Genetic polymorphisms in the interleukin-1 gene cluster have been associated with the severity of periodontal diseases featured by a variable degree of destruction of connective tissueINTRODUCTION: Genetic polymorphisms in the interleukin-1 gene cluster have been associated with the severity of periodontal diseases featured by a variable degree of destruction of connective tissue and bone, such as periodontitis and periimplantitis. This study was aimed to investigate if a link exists between such interleukin-1 gene polymorphisms and the development of gingival recessions during orthodontic treatment in Italian children. METHODS: We evaluated, in 74 young Italian patients of both sexes, the -889 C/T polymorphism of the interleukin-1alpha gene and the -511 C/T and +3954 C/T polymorphisms of interleukin-1alpha gene by polymerase chain reactions-restriction fragment length polymorphism method using NcoI, AvaI and TaqI as restriction enzymes. RESULTS: No association of interleukin-1 genotypes investigated and gingival recession occurring during orthodontic treatment were identified. CONCLUSION: In the population studied specific interleukin-1 genotypes (linked to a higher susceptibility to bone resorption in periodontal disease) there does not appear to be any association with the development of gingival recessions during orthodontic treatment.

• The orthodontic treatment of TMD patients: EMG effects of a functional appliance.

  Authors: Tommaso Castroflorio, Cristina Titolo, Andrea Deregibus, Cesare Debernardi, Pietro Bracco

  Cranio : the journal of craniomandibular practice. 08/2007; 25(3):206-12.

  The aim of this work was to test the effects of the Function Generator Bite (FGB) on the masticatory muscles of temporomandibular joint dysfunction (TMD) subjects. Two groups were selected for theThe aim of this work was to test the effects of the Function Generator Bite (FGB) on the masticatory muscles of temporomandibular joint dysfunction (TMD) subjects. Two groups were selected for the study. A group of 20 TMD patients (group F) requiring orthodontic treatment and treated with FGB and a group of 10 healthy subjects (group H) were considered. Both groups were evaluated before the therapy began (TO) and then after 18 months of therapy (T1). An electromyographic analysis of the masseter and temporalis anterior muscles and a clinical evaluation according to the Research Diagnostic Criteria for TMD (RDC/TMD) were performed. A statistical difference between the two groups was observed at TO with respect to the activity index. TMD subjects showed a lower value of the index. Further studies are necessary to fully understand the utility of this EMG index as a diagnostic indicator.

• Effect of bolus hardness on the chewing pattern and activation of masticatory muscles in subjects with normal dental occlusion.

  Authors: Maria Grazia Piancino, Pietro Bracco, Teresa Vallelonga, Andrea Merlo, Dario Farina

  Journal of electromyography and kinesiology : official journal of the International Society of Electrophysiological Kinesiology. 08/2007;

  The aim of the study was to evaluate the effect of bolus hardness on the kinematic of mastication and jaw-elevator muscle activity in subjects with normal dental occlusion and function. TheThe aim of the study was to evaluate the effect of bolus hardness on the kinematic of mastication and jaw-elevator muscle activity in subjects with normal dental occlusion and function. The mandibular motion and the surface EMG envelope of the masseter and temporalis anterior muscles were assessed in twelve subjects during mastication of a soft and hard bolus of the same size. When chewing the hard bolus, the chewing pattern in the frontal plane was significantly higher and wider, with smaller closure angle and higher peak velocity than when chewing the soft bolus. EMG peak amplitude of both the masseter and anterior temporalis muscles was higher for the side of the bolus but the contralateral side increased its activity significantly more than the ipsilateral side when the hardness of the bolus increased (for the masseter, mean+/-SD: 130.4+/-108.1% increase for the contralateral side and 29.6+/-26.9% for the ipsilateral side). Moreover, the peak EMG activity for both muscles occurred more distant from the closure point with hard bolus. The increased activity of the contralateral side may help maintaining the mandibular equilibrium, with indirect participation to the power stroke generated by the chewing-side masseter. The results provide kinematic and EMG adaptations to bolus hardness in healthy subjects and can be used as normative data in the development of methods for early diagnosis of impaired chewing function.

• Early treatment with "function generating bite" of a left unillateral posterior cross-bite: chewing pattern before and after therapy with FGB.

  Authors: Maria Grazia Piancino, Dario Farina, Andrea Merlo, Mariagrazia Greco, Matteo Aprato, Pietro Bracco

  International journal of orthodontics (Milwaukee, Wis.). 02/2007; 18(2):33-8.

  A case of a 5.2 years-old child, with a left unilateral posterior cross-bite, from the canine to the second deciduous molar, corrected with the functional appliance "Function Generating Bite" (FGB)A case of a 5.2 years-old child, with a left unilateral posterior cross-bite, from the canine to the second deciduous molar, corrected with the functional appliance "Function Generating Bite" (FGB) is reported. The chewing cycles were recorded before and 6 months after correction. The number of reverse chewing cycles on the cross-bite/corrected side decreased significantly six months after therapy (2% with the soft bolus and 4% with the hard bolus) with respect to the initial condition (70% with the soft bolus and 79% with the hard bolus). In conclusion, the FGB achieved the orthodontic correction and also corrected the masticatory function.

• Chewing pattern before and after unilateral posterior cross-bite therapy with function generating bite: a case report.

  Authors: Maria Grazia Piancino, Francesca Talpone, Tanja Bole, Matteo Reverdito, Cesare Debernardi, Pietro Bracco

  Progress in orthodontics. 02/2007; 8(1):74-86.

  OBJECTIVES: To evaluate the chewing-cycle closing direction of a patient with a posterior unilateral crossbite, before treatment, six months and one year after correcting the malocclusion with aOBJECTIVES: To evaluate the chewing-cycle closing direction of a patient with a posterior unilateral crossbite, before treatment, six months and one year after correcting the malocclusion with a function generating bite. METHODS AND MATERIALS: An 8-year-old girl with right unilateral posterior cross-bite was treated with a function generating bite, which corrected the cross-bite within 5 months. Mandibular movements during mastication of a soft and of a hard bolus were recorded before and after treatment with a K6 I kinesiograph (Myotronics Inc., Seattle, WA-USA). RESULTS: Initially, there was a marked prevalence of chewing cycles with a reverse direction of closure (92% for the soft bolus and 92% for the hard bolus) during mastication on the cross-bite side. Six months after correction, during mastication on the corrected side, the percentage of chewing cycles with reverse closure decreased to 2% for the soft and 0% for the hard bolus. This decrease was still evident one year after correction (0% for the soft bolus and 18% for the hard bolus). Mastication on the healthy side at all times presented cycles with normal closing direction. CONCLUSIONS: Analysis of masticatory cycles recorded before and after orthodontic therapy showed that not only was anatomic correction achieved by the function generating bite, but also that masticatory function had regained equilibrium and symmetry and both were stable at least 1 year after the cross bite was corrected.

• Reverse-sequencing chewing patterns before and after treatment of children with a unilateral posterior crossbite.

  Authors: Maria Grazia Piancino, Francesca Talpone, Paola Dalmasso, Cesare Debernardi, Arthur Lewin, Pietro Bracco

  European journal of orthodontics. 11/2006; 28(5):480-4.

  The aim of this study was to compare the percentage of reverse-sequencing chewing cycles in 22 children [9 boys and 13 girls; mean age +/- SD, 8.6 +/- 1.3 and 8.8 +/- 1.5 years, respectively), with aThe aim of this study was to compare the percentage of reverse-sequencing chewing cycles in 22 children [9 boys and 13 girls; mean age +/- SD, 8.6 +/- 1.3 and 8.8 +/- 1.5 years, respectively), with a unilateral right or left posterior crossbite, before and after therapy. The chewing cycles were recorded using a kinesiograph while the subjects masticated a soft and a hard bolus on both the crossbite and non-crossbite side. Chewing data were acquired before and 6 months after orthodontic treatment of the crossbite with an orthodontic functional appliance, the 'Function Generating Bite'. The results showed that, before therapy, the percentage of reverse-sequencing chewing cycles on the crossbite side was significantly higher than that on the normal side (P < 0.001) with both the soft and hard bolus. In addition, the percentage of reverse-sequencing chewing cycles on the crossbite side before therapy was significantly greater than after therapy with both a soft and hard bolus (P < 0.001). No significant differences were found in the percentage of reverse-sequencing chewing cycles on the non-crossbite side, before or after therapy, either with a soft or hard bolus.

• Quantitative analysis of the variability of unilateral chewing movements in young adults.

  Authors: Virgilio F Ferrario, Maria G Piancino, Claudia Dellavia, Tommaso Castroflorio, Chiarella Sforza, Pietro Bracco

  Cranio : the journal of craniomandibular practice. 11/2006; 24(4):274-82.

  Kinesiography can be used as a diagnostic tool in a dental clinic context. In the current study, a kinesiograph was used to detect and record the three-dimensional motion of the mandibularKinesiography can be used as a diagnostic tool in a dental clinic context. In the current study, a kinesiograph was used to detect and record the three-dimensional motion of the mandibular mid-incisor point during unilateral chewing as a function of time. The aim of the study was to quantify the within-subject short-term reproducibility of the kinesiographic recordings in normal, healthy subjects. Ten seconds of unilateral (right and left) gum chewing were recorded in 20 control subjects using computerized kinesiography. Each subject performed 18 chewing sequences (three repetitions x three sessions x two sides). Chewing cycle duration, volume, standardized depth and width, and the number of reversed cycles were calculated. Intraclass correlation coefficients (two-way random effects analysis of variance with interactions) and paired t-tests were used to compare sessions. For each subject and side, chewing variability was expressed as the coefficient of variation (percentage ratio of standard deviation to mean) of each variable. Mean left and right side mastications were computed over all sessions and subjects. For all the analyzed variables, larger variations between subjects (analysis of variance, p < 0.001) than between sessions were found, with intraclass correlation coefficients ranging between 0.432 (left side cycle duration) and 0.989 (right side standardized width). No systematic errors between the three measurement sessions were found for cycle volume and shape (paired t, p > 0.05). The highest between subjects/ between sessions variance ratios (up to 223.28) were found for cycle duration and shape. In all subjects, chewing cycle volume was very variable, with mean coefficients of variation up to 47% (left side in females). Cycle duration and standardized depth and width were more reproducible, with mean coefficients of variation up to 10% (duration), 14% (standardized width), and 18% (standardized depth). The spatial characteristics of gum chewing cycles had a large within-subject variability. The temporal and size-standardized (shape) characteristics were more consistent within subject. The results should allow selection of a set of relatively more consistent variables for the definition of normality and the comparison of patients.

• Reproducibility of surface EMG in the human masseter and anterior temporalis muscle areas.

  Authors: Tommaso Castroflorio, Katia Icardi, Ferruccio Torsello, Andrea Deregibus, Cesare Debernardi, Pietro Bracco

  Cranio : the journal of craniomandibular practice. 05/2005; 23(2):130-7.

  The aim of this study was to test the hypothesis that surface electromyography (sEMG) recordings, made at mandibular rest position from the masseter and temporalis anterior areas, are intra- andThe aim of this study was to test the hypothesis that surface electromyography (sEMG) recordings, made at mandibular rest position from the masseter and temporalis anterior areas, are intra- and inter-session reproducible. A template was designed and built to permit the correct electrode placement from one session to the next session. A sample of 18 subjects was examined. Two groups, homogeneous for age, sex, and craniofacial morphology were selected. The first group included asymptomatic subjects with no signs or symptoms of temporomandibular joint dysfunction (TMD) and the second group included patients suffering from muscle-related TMD. Data were obtained from different sEMG recordings made at mandibular rest position in the same session and in different sessions, repositioning the electrodes using a template designed for that purpose. The electromyograph used in this, study is part of the EMG K6-I Win Diagnostic System. Results showed that reproducibility of sEMG signals from the masseter and anterior temporalis areas at mandibular rest position is possible.

• Chewing cycle analysis-a new clinical tool.

  Authors: Pietro Bracco, Andrea Deregibus

  International journal of orthodontics (Milwaukee, Wis.). 02/2005; 16(2):9-19.