Efficacy and Safety of Botulinum Toxin Type A on Persistent Myofascial Pain: A Randomized Clinical Trial.

This study assessed the safety and efficacy of three different doses of BoNT-A for persistent myofascial pain (MFP). One hundred female subjects were randomly assigned into five groups (n = 20): oral appliance (OA), saline solution (SS) and three BoNT-A groups with different doses. Pain intensity and pressure pain threshold were evaluated up to 24 weeks after treatment. Adverse effects related to muscle contraction, masticatory performance, muscle thickness and mandibular bone volume were also assessed. Changes over time were compared within and between groups. The "nparLD" package and Wilcoxon signed-rank test were used to analyze the data. BoNT-A reduced pain intensity (p < 0.0001) and increased pressure pain threshold (p < 0.0001) for up to 24 weeks compared to the placebo. No differences were found between BoNT-A and OA at the last follow-up. A transient decline in masticatory performance (p < 0.05) and muscle contraction (p < 0.0001), and a decrease in muscle thickness (p < 0.05) and coronoid and condylar process bone volume (p < 0.05) were found as dose-related adverse effects of BoNT-A. Regardless of the dose, BoNT-A was as effective as OA on MFP. Notwithstanding, due to BoNT-A dose-related adverse effects, we suggest the use of low doses of BoNT-A in MFP patients that do not benefit from conservative treatments.

Toxina Botulínica para el Tratamiento de los Desórdenes Temporomandibulares / Botulinum Toxin for the Treatment of Temporomandibular Disorders

RESUMEN: Los Trastornos Temporomandibulares (TTM) consisten en un conjunto de condiciones patológicas que afectan la articulación temporomandibular (ATM), los músculos de la masticación y las estructuras asociadas. Estudios epidemiológicos estiman que 40 % a 75 % de la población adulta presenta por lo menos un signo de TTM, como ruido articular y 33 % por lo menos un síntoma, como dolor facial o en la ATM. La toxina botulínica (BoNT) es una neurotoxina producida por la bacteria anaerobia Clostridium botulinum, solo la toxina A y B son utilizadas en la práctica clínica después de la aprobación de la Food and Drug Administration en 1989 y 2000; actualmente continúan siendo utilizadas para tratar varias condiciones de dolor, incluyendo la espasticidad muscular, distonia, dolor de cabeza y dolor miofascial. Las propuestas del mecanismo de acción fueron sugeridas a mediados de 1950 manifestando que esta neurotoxina posee alta afinidad con la sinapsis colinérgicas, ocasionando un bloqueo en la liberación de acetilcolina de esos terminales nerviosos, sin alterar la conducción neural de las señales eléctricas o en la síntesis de almacenamiento de acetilcolina. La inyección intramuscular en dosis y localización apropiada, provoca denervación química parcial y disminución de la contractura, sin ocasionar parálisis completa a lo que se le atribuye ser un innovador y eficaz método de tratamiento para el dolor crónico asociada con hiperactividad de los músculos masticatorios. La toxina botulínica tipo A es ser una alternativa para el control de la sintomatología dolorosa presente en los TTMs de etiología miogénica. Los autores recomiendan realizar un correcto diagnóstico, ya que la indicación de este tipo de tratamiento con diagnósticos incorrectos lleva a resultados inciertos.

ABSTRACT: Temporomandibular Disorders (TMD) is a term that was used to describe a set of pathological conditions that affect temporomandibular joint (TMJ), muscles of mastication and associated structures. Epidemiological studies estimates that 40 % to 75 % of the adult population has at least one sign of TMD, such as joint noise and 33 % presented some symptom such as facial or joint pain. Botulinum toxin is a neurotoxin produced by the anaerobic bacterium Clostridium botulinum. There are two types of toxin (A and B) used in clinical practice that were approved by Food and Drug Administration in 1989 and 2000. These medications are in use to treat various diseases including muscle spasticity, dystonia, headache and myofascial pain. The mechanisms of action were suggested in the mid-1950s, this neurotoxin seems to have an action at cholinergic synapses, causing a block in the release of acetylcholine from the nerve terminals without altering the neural conduction of the electrical signals. The synthesis and storage of acetylcholine were preserved. Intramuscular injection in appropriate doses and location causes partial chemical denervation and decreased contracture, without causing complete paralysis of muscles. Due to this features, it has been considered an innovative and effective method to treat chronic pain associated with hyperactivity of masticatory muscles. The botulinum toxin type A appears to be an alternative method for pain control present in TMDs that have myogenic etiology. The authors recommend a correct diagnosis, since the indication of this type of treatment associated with an incorrect diagnosis leads to uncertain outcomes, creating false conclusions.

Quality of life of patients with facial prosthesis / Calidad de vida de los pacientes portadores de prótesis faciales

ABSTRACT. Objective: evaluate the quality of life and self-esteem of patients with facial deformities in the nasal, oculo-palpebral, and auricular areas using bucco-maxillofacial prostheses. Methods: descriptive study in users of facial prostheses who were rehabilitated at the dental clinic of the University Hospital of Brasilia in the period 2004-2011. The average age of patients was 63.8 years. The data collection instruments were the SF-36 questionnaire and a survey containing the Rosenberg Self-Esteem/EPM scale. Results: skin cancer was the predominant etiologic factor (n = 4). Most patients think that their deformity is visible to some degree (n = 4) and for three of them this fact impacts negatively the frequency to visit public places. The self-esteem scale yielded an average score of 4.6. In evaluating the quality of life by means of the SF-36 questionnaire, there were scores like pain (46.67) and emotional aspects (33.33). Conclusion: the results demonstrate the importance of conducting systematic followups to these patients. Most surveyed patients experienced an increase in quality of life, as well as a higher self-esteem, which can be explained by the functionality and aesthetics offered by the prosthesis. This study is part of an assessment program conducted with the intention of structuring multidisciplinary rehabilitation programs.

RESUMEN. Objetivo: evaluar la calidad de vida y la autoestima de los pacientes con deformidades faciales en la zona nasal, la zona óculopalpebral y la región auricular, portadores de prótesis bucomaxilofaciales. Métodos: estudio descriptivo en pacientes usuarios de prótesis faciales, los cuales fueron rehabilitados en la clínica odontológica del Hospital Universitario de Brasilia en el periodo 2004-2011. La edad media de los pacientes evaluados fue de 63,8 años. Como instrumentos de recolección de datos, en esta investigación se utilizaron el cuestionario SF-36 y una encuesta que contenía la Escala Visual de Autoestima de Rosenberg ̸EPM. Resultados: el cáncer de piel fue el factor etiológico predominante (n = 4). La mayoría de los pacientes consideró que su deformidad es visible en algún grado (n = 4), y para tres de ellos este hecho interfiere negativamente en la frecuencia de visitas a sitios públicos. En la escala de autoestima se obtuvo una puntuación media de 4,6. En la evaluación de la calidad de vida utilizando el cuestionario SF-36 se obtuvieron valores como dolor (46,67) y aspectos emocionales (33,33). Conclusión: los resultados demuestran la importancia de hacer un seguimiento sistemático a estos pacientes. En la mayoría de los pacientes encuestados se identificó un aumento en la calidad de vida, así como una mayor autoestima, lo cual puede explicarse por la funcionalidad y estética desempeñada por la prótesis. Esta es una propuesta de evaluación que se llevó a cabo con el fin de estructurar programas de rehabilitación multidisciplinar.

Retention and Mechanical Behavior of Attachment Systems for Implant-Retained Auricular Prostheses.

OBJECTIVE: Auricular prostheses are artificial substitutes for facial defects. The retention of these has often been a problem. This study aimed to evaluate the mechanical behavior of 3 retained auricular prosthetic connections when submitted to a mechanical cycling test. MATERIALS AND METHODS: Twelve samples with installed implants were obtained and divided into 3 groups according to their retention system with 4 samples in each group. I: bar-clip system; II: magnet system; and III: ball/o-ring system. Each of samples was submitted to the pull-out test during 3240 cycles (f = 0.5 Hz) to determine its tensile strength. The mechanical cycling test was performed using the servo-hydraulic machine MTS 810-Flex Test 40 (Eden Prairie, MN) that had a 2.5 mm shift at a 10 mm/s velocity. The retaining strength for each of the samples was obtained at 7 intervals. RESULTS: The tensile strength for the group retained by the bar-clip system (29.60 N) was higher with statistically significant difference (P < 0.05) when compared with the group retained by the ball/o-ring system (9.41 N) and magnets system (8.61 N) for all periods assessed. The ball/o-ring system showed loss of retention during the fatigue test (Kruskal-Wallis, chi-squared = 17.28; P < 0.01). CONCLUSIONS: The evaluated systems showed a tensile strength compatible with the clinical use and no fractures of the components were observed.

Bisphosphonate-related osteonecrosis of the jaw: a review of the literature.

Bisphosphonates (BPs) are a class of drugs used to treat osteoporosis and malignant bone metastasis. BPs show high binding capacity to the bone matrix, especially in sites of active bone metabolism. The American Society for Bone and Mineral Research defines BRONJ as "an area of exposed bone in the maxillofacial region that has not healed within 8 weeks after identification by a healthcare provider in a patient who is receiving or has been exposed to a bisphosphonate and has not had radiation therapy to the craniofacial region." Bisphosphonate-related osteonecrosis of the jaw (BRONJ) can adversely affect quality of life, as it may produce significant morbidity. The American Association of Oral and Maxillofacial Surgeons (AAOMS) considers as vitally important that information on BRONJ be disseminated to other dental and medical specialties. The purpose of this work is to offer a perspective on how dentists should manage patients on BPs, to show the benefits of accurately diagnosing BRONJ, and to present diagnostic aids and treatments strategies for the condition.