ABSTRACT
Changes involving temporomandibular joint, masticatory musculature, and associated structures characterize temporomandibular dysfunction (TMD). The analgesic and anti-inflammatory effect produced by photobiomodulation has contributed to pain relief and functional improvement. However, the parameters to be used have not yet been well established. The aim of this study is to compare the efficacy of three different photobiomodulation dosimetries in the treatment of patients with TMD. A randomized, double-blind, placebo-controlled clinical trial with 44 subjects divided into the groups 8 J/cm2 (n = 11), 60 J/cm2 (n = 11), 105 J/cm2 (n = 11), and control (n = 11). Pain, symptom severity, and joint mobility were evaluated before and after a ten-session protocol of photobiomodulation with AlGaAs laser (830 nm), at a power density of 30 mW/cm2. The mouth opening increased in the 8-J/cm2 group from 10.49 ± 4.68 to 15.40 ± 6.43 degrees, and in the right protrusion from 9.80 ± 4.2 to 12.56 ± 5.40 degrees after the intervention protocol (p < 0.05). All groups significantly decreased pain (p < 0.05). 830-nm laser photobiomodulation was effective in reducing TMD pain and symptoms at all doses tested. Only the doses of 8 J/cm2 were effective regarding maximal opening and protrusion of the mandible.
Subject(s)
Low-Level Light Therapy , Radiometry , Temporomandibular Joint Disorders/physiopathology , Temporomandibular Joint Disorders/radiotherapy , Adolescent , Adult , Double-Blind Method , Female , Humans , Male , Mandible/physiopathology , Mandible/radiation effects , Middle Aged , Placebos , Range of Motion, Articular , Surveys and Questionnaires , Temporomandibular Joint/physiopathology , Temporomandibular Joint/radiation effects , Young AdultABSTRACT
PURPOSE: To analyze, in vitro, the influence of a quartz-tungsten-halogen (QTH) and a plasma arc (PAC) on the degree of conversion and hardness of a composite resin, as well as the heat generated by the units. METHODS: Transbond XT disks were prepared and light-cured for 10, 20 and 30 seconds with a QTH (Curing Light XL 3000) or with a PAC (Apollo 95E) for 1, 2 and 3 seconds. The composite resin polymerization was evaluated by infrared spectrophotometry (FTIR) and Knoop hardness number (KHN). The temperature at the curing tip was evaluated. The results were analyzed using ANOVA and Tukey test (α=0.05). RESULTS: According to FTIR and KHN, the polymerization of the composite resin was statistically higher with the QTH. The temperature obtained with the QTH 20 s (45.44ºC) and 30 s (45.84ºC) was statistically higher than the QTH 10 s (39.90ºC). The PAC 1 s (27.12ºC), 2 s (28.48ºC) and 3 s (29.96ºC) presented the lowest temperature and did not differ statistically among them. CONCLUSION: Transbond XT light-activated for 10, 20 and 30 seconds with the QTH presented higher degree of conversion and hardness in comparison with those obtained with the PAC for 1, 2 and 3 seconds, and the QTH generated more heat than the PAC.
OBJETIVO: Analisar, in vitro, as fontes luminosas Halógena (QTH) e Xenon (PAC) no grau de conversão e dureza de uma resina composta e também o calor gerado por estas unidades. METODOLOGIA: discos com resina Transbond XT foram fotoativados por 10, 20 e 30 segundos com QTH (Curing light XL 3000) ou com PAC (Apollo 95E) por 1, 2 e 3 segundos. A resina composta foi analisada por meio de espectrofotometria infravermelha (FTIR) e pelo teste de dureza Knoop (KHN). A temperatura na ponta dos aparelhos foi também avaliada. Os resultados foram analisados usando ANOVA e Tuckey test (α=0.05). RESULTADOS: Conforme FTIR e KHN a polimerização do compósito foi estatisticamente maior com QTH. A temperatura obtida do QTH com 20 segundos (45,44ºC) foi estatisticamente maior do que com 10 segundos (39,90ºC). O PAC com 1, 2 e 3 segundos apresentou as temperaturas mais baixas e não diferem estatisticamente entre si. CONCLUSÃO: A resina Transbond XT fotoativada por 10, 20 e 30 segundos com QTH apresentou maior grau de conversão e dureza em comparação com PAC por 1, 2 e 3 segundos. O QTH produziu mais calor que o PAC.
Subject(s)
Hardness/physiology , Curing Lights, Dental , Composite Resins , Xenon/pharmacologyABSTRACT
The purpose of this study was to assess the influence of two light units, a quartz-tungsten-halogen (QTH) and a light-emitting diode (LED), on the hardness and degree of conversion of an orthodontic composite resin. Sixty specimen disks were prepared from Transbond XT composite resin (3M Unitek) and light cured for 10, 20, and 30 seconds with a QTH (Curing Light XL 3000, 3M Unitek) or a LED (Ortholux, 3M Unitek) light-curing unit for 5, 10, and 15 seconds. Composite resin polymerization was evaluated by Fourier-transform infrared (FTIR) spectrophotometry and Knoop hardness number (KHN). The results were statistically analysed using analysis of variance and Tukey's multiple comparisons test (alpha = 0.05). The highest KHN was obtained with the QTH at 30 (25.19 KHN) and 20 (24.01) seconds, which did not differ statistically, and in the LED 15 second (21.86) group. The QTH 10 second group (20.53) did not differ statistically from the QTH 20 second or the LED 5 (19.96) and 15, or 10 second (18.95) groups. According to FTIR, there was no statistical difference for the degree of conversion among the groups, QTH 10 (43.42 per cent), QTH 20 (46.12 per cent), QTH 30 (45.30 per cent), LED 10 (47.02 per cent), or LED 15 (47.24 per cent) seconds. The lowest degree of conversion was obtained for the LED 5 second group (38.97 per cent), which did not differ statistically from the QTH 10 second group. Light curing with the LED resulted in a reduction of 50 per cent in the time recommended for use of the QTH light with the composite resin, Transbond XT.
Subject(s)
Composite Resins/radiation effects , Curing Lights, Dental/classification , Dental Cements/radiation effects , Hardness , Orthodontics/instrumentation , Resin Cements/radiation effects , Analysis of Variance , Materials Testing , Spectroscopy, Fourier Transform Infrared , Statistics, Nonparametric , Time FactorsABSTRACT
Foi realizada uma pesquisa de campo em duas escolas da rede pública estadual de Porto Alegre, com a finalidade de verificar a presença de dentes permanentes irrompidos em crianças com faixa etária entre seis a dez anos. Foram examinadas 327 crianças, considerando as variáveis de idade, sexo e raça. Não foi observada diferença significativa para a época de erupção para as variáveis de raça e sexo. Foi observado que aos seis anos de idade uma porcentagem maior de incisivos inferiores (78,7%) irrompeu antes que os primeiros molaresinferiores (75,9%), assim como a erupção na arcada inferior antecedeu a da arcada superior. O trabalho teve como referência didática uma ampla literatura sobre os diferentes tópicosrelacionados ao processo evolutivo da dentição.
A survey was performed in two public schools of Porto Alegre, with the purpose of demonstrate the presence of erupted pennanent teeth in children with age ranging from 6 to 1 O years old. The sample consisted of 327 patients and the variables examined were age, sex and race. In the 6 year old group, the lowers incisors (78,7%) erupted earlier than the first molars(75,9%) and the teeth on the lower arch erupted before the teeth on upper arch. It was not observed a significant difference (p<0,05) in the time of eruption of the teeth for the variablessex and race. A literature review of teeth evolution process and related factors were alço described.
