Comparative evaluation of the efficacy of occlusal splints fabricated in centric relation or maximum intercuspation in temporomandibular disorders patients

Fabrication of occlusal splints in centric relation for temporomandibular disorders (TMD) patients is arguable, since this position has been defined for asymptomatic stomatognathic system. Thus, maximum intercuspation might be employed in patients with occlusal stability, eliminating the need for interocclusal records. This study compared occlusal splints fabricated in centric relation and maximum intercuspation in muscle pain reduction of TMD patients. Twenty patients with TMD of myogenous origin and bruxism were divided into 2 groups treated with splints in maximum intercuspation (I) or centric relation (II). Clinical, electrognathographic and electromyographic examinations were performed before and 3 months after therapy. Data were analyzed by the Student's t test. Differences at 5 percent level of probability were considered statistically significant. There was a remarkable reduction in pain symptomatology, without statistically significant differences (p>0.05) between the groups. There was mandibular repositioning during therapy, as demonstrated by the change in occlusal contacts on the splints. Electrognathographic examination demonstrated a significant increase in maximum left lateral movement for group I and right lateral movement for group II (p<0.05). There were no significant differences (p>0.05) in the electromyographic activities at rest after utilization of both splints. In conclusion, both occlusal splints were effective for pain control and presented similar action. The results suggest that maximum intercuspation may be used for fabrication of occlusal splints in patients with occlusal stability without large discrepancies between centric relation and maximum intercuspation. Moreover, this technique is simpler and less expensive.

Conexões implante-abutment / Implant-abutment connections

O sucesso em longo prazo dos implantes osseo integrados tem sido bem estabelecido na literatura. Entretanto, um problema mecânico comumente associado com implantes em restaurações unitárias é a instabilidade na interface implante-abutment. Assim, o objetivo deste trabalho foi realizar, por meio de uma revisão bibliográfica, um estudo comparativo entre os vários tipos de conexões externas e internas disponíveis, na tentativa de estabelecer qual tipo de conexão apresenta um melhor comportamento biomecânico em próteses unitárias. Concluiu-se que deve haver uma avaliação criteriosa das características de cada sistema e de cada marca comercial. Quanto menor a tolerância durante a fabricação dos componentes, mais precisa e estável será a interface implante-abutment. Além disso, um sistema mais resistente muitas vezes não é o melhor sistema, pois devemos sempre levar em conta a tolerância biológica. A tolerância ao estresse deve ser menor no complexo implante-prótese, preferencialmenteno parafuso, do que no tecido ósseo adjacente.

The long-term success of dental implants has been very established in the literature. However, a mechanical problem commonly associated to single implant is the implant-abutment interface instability, specifi cally the screw loosening or fractures. In this way, the purpose of this article was to accomplish, through a review of literature, a comparative study among the several types of external and internal connections available, attempting to establish which connection type presents better biomechanical behavior in single tooth restorations. It was concluded that a careful evaluation of the features of each system and manufacturers. The smaller the tolerance during components fabrication, the more accurate and stable will be the implant-abutment interface. Besides, many times, a more resistant system is not the best system because the biologic tolerance is very important. The stress tolerance must be smaller in the implant-prosthesis complex, mainly in the screw, than in the bone around.

Evaluation of tissue response to periodontal dressings: histological study in tooth sockets of rats

Although the use of periodontal dressings is currently limited, there are some indications for their use. Selection of any material that will have direct contact with live tissues, such as periodontal dressings, should be careful in order to allow surgical wound healing. The aim of this study was to evaluate the intensity of inflammatory response and bone formation in tooth sockets of rats after implantation of three periodontal dressings. After removal of the right maxillary incisors of 84 male rats, each tooth socket received implantation of a polyethylene tube, 63 of which were filled with non-eugenol periodontal dressing and the remaining 21 tubes remained empty (control group). Histological evaluation assessed the intensity of inflammatory response and presence and location of bone tissue formation at postoperative periods of 7, 14 and 28 days. Statistical analysis was performed by the Kruskal-Wallis test at 5% significance level. Regarding the inflammatory infiltrate, at 28 days, there was statistically significant difference between one of periodontal dressings and control group (p<0.05). Analysis of postoperative periods, showed that the control group presented statistically significant reduction in the inflammatory infiltrate comparing the 14- and 28-day periods (p<0.05). Regarding bone tissue formation, there was difference in control group between the 7- and 28-day periods (p<0.05). Within the experimental conditions, it may be concluded that no differences were found in the inflammatory response among the groups at 7 and 14 days and that Voco pac™ dressing induced a more intensive inflammatory reaction at 28 days.

Como entender o tratamento odontológico de idosos com deficiências / How to understand dental treatment of elderly people with deficiency

Apesar da necessidade de uma maior atenção à odontologia em nosso país, tendo em vista o crescente aumento da população de idosos, a maioria das faculdades de odontologia não incluiu, até o presente momento, esta ciência em seus currículos. De tal forma, a maioria dos profissionais encontra-se ainda despreparada para prestar um atendimento ideal à população de terceira idade, especialmente aos idosos portadores de deficiências. Este artigo irá abordar aspectos importantes sobre pacientes idosos com dificuldades visuais, auditivas, mentais, ortopédicas ou de fonação, além de fornecer indicações para montagem de uma clínica mais adequada para servir estes pacientes com necessidades especiais

Evaluation of microcurrent electrical nerve stimulation (MENS) effectiveness on muscle pain in temporomandibular disorders patients

A efetividade da Estimulação Neural Elétrica por Microcorrente (MENS) foi avaliada e comparada à terapia por Placas Oclusais em pacientes com desordens temporomandibulares (DTM) de origem muscular. Vinte pacientes foram divididos em quatro grupos. Um recebeu a terapia por placas interoclusais e MENS (I); outro, placas e MENS placebo (II), o terceiro, somente MENS (III) e o último grupo, MENS placebo (IV). Os resultados obtidos foram submetidos a uma análise de variância (p<0,05). Houve redução dos níveis de dor em todos os grupos: o grupo I (placas e MENS) obteve uma taxa de redução de 47,7%; o grupo II (placa e MENS placebo), 66,7%; o grupo III (MENS), 49,7% e o grupo IV (MENS placebo), 16,5%. Apesar disso, não se verificaram diferenças estatisticamente significantes entre MENS e utilização de placas interoclusais em relação à diminuição de dor muscular em pacientes com DTMs após 4 semanas.

Evaluation of microcurrent electrical nerve stimulation (MENS) effectiveness on muscle pain in temporomandibular disorders patients%Avaliação da efetividade da estimulação neural elétrica por microcorrentes (MENS) na dor muscular em pacientes com desordem temporomandibular

A efetividade da Estimulação Neural Elétrica por Microcorrente (MENS) foi avaliada e comparada à terapia por Placas Oclusais em pacientes com desordens temporomandibulares (DTM) de origem muscular. Vinte pacientes foram divididos em quatro grupos. Um recebeu a terapia por placas interoclusais e MENS (I); outro, placas e MENS placebo (II), o terceiro, somente MENS (III) e o último grupo, MENS placebo (IV). Os resultados obtidos foram submetidos a uma análise de variância (p<0,05). Houve redução dos níveis de dor em todos os grupos: o grupo I (placas e MENS) obteve uma taxa de redução de 47,7%; o grupo II (placa e MENS placebo), 66,7%; o grupo III (MENS), 49,7% e o grupo IV (MENS placebo), 16,5%. Apesar disso, não se verificaram diferenças estatisticamente significantes entre MENS e utilização de placas interoclusais em relação à diminuição de dor muscular em pacientes com DTMs após 4 semanas

A stereological analysis of the heterotopic osteogenesis induced by allogenic bone matrix graafts in rat subcutaneous tissue

The subcutaneous cellular and tissue alterations that occur during heterotopic osteogenesis induced by a demineralized bone matrix graft in rats were studied morphometrically. Diaphysis segments obtained from 42 rat femurs were cleaned and demineralized with 0. 6 M HCl. Each segment was filled with a blood clot and implanted into the back of rats (1 segment/rat). Histological speciemens were collected 2, 5, 7, 14, 21, 28 and 49 days after implantation (6 rats/period) and processed after demineralization. Qualitative and morphometric analysis of the histological sections showed that the external blood clots and those filling the medullary canal were replaced with connective tissue within 2-5 days pos-implantation. After 14 days, 11, 2 per cent and 0, 5 per cent of the implanted matrix was replaced with areas of resorption nd hyaline cartilage, respectively. After 21 days, 13, 7 per cent, 2, 4 per cent and 2, 7 per cent of the graft matrix showed areas of resorption, cartilage tissue and bone tissue, respectively. At the end of the 49-day study period, 20, 2 per cent, 7, 8 per cent and 14, 5 per cent of the matrix was replaced with areas of resorption, bone tissue and hematopoietic tissue, respectively. Bone induction in rat subcutaneous tissue occurred only at the site of allogenic matrix implantation. the quantity of neoformed cartilage, bone and myeloid tissue depended on the volume of matrix implanted and on the microenviromental conditions, and was regulated temporally by a cascade of events mediated by bone morphogenetic proteins (BMPs) presents in the graft. These results also show that morphometric methods may be useful for assessing osteoinduction at ectopic sites.