RESUMO
Approximately 34-86% of neoplasms of the salivary glands are located in the parotid gland and parotidectomy is the first-line treatment for parotid gland tumors. Frey syndrome and cosmetic deformity are common complications experienced by patients following parotidectomy and the sternocleidomastoid muscle flap (SCMF) is used to prevent them. Numerous studies have been performed to examine the effectiveness of the SCMF for the prevention of cosmetic deformity and Frey syndrome, however, they provide contradictory results and possess small sample sizes with consequently low statistical power. In order to evaluate the effectiveness of the SCMF for the prevention of Frey syndrome and cosmetic deformity following parotidectomy, we performed a systematic review and meta-analysis based on published randomized controlled trials (RCTs), which were identified using PubMed and CNKI databases, and references of studies up to August 2012 were included. Using these criteria, we yielded 11 RCTs. Following an independent assessment of the methodological quality of these studies and the extraction of data, a systematic review and meta-analysis was conducted. The results of the meta-analysis demonstrated that there was a significant trend towards a lower risk of objective incidence [67%; risk ratio (RR), 0.33; 95% confidence interval (CI), 0.16-0.67; P<0.01] and subjective incidence (66%; RR, 0.34; 95% CI, 0.16-0.75; P= 0.01) of Frey syndrome in the SCMF group. The sensitivity analysis also indicated that this result was significant. Due to the considerable variation between the included studies, a meta-analysis was not applicable to assess cosmetic deformity. Two RCTs demonstrated that the difference between the SCMF and no SCMF group was not statistically significant, while the other seven RCTs detected a statistically significant difference between the two groups. Publication bias was detected. In conclusion, based on currently available evidence, the use of the SCMF is benefical for the prevention of Frey syndrome, however, whether it is also benefical for cosmetic deformity remains inconclusive.
RESUMO
OBJECTIVE: To investigate the effect of muscular rehabilitation on recovery after sagittal split ramus osteotomy. METHODS: Twenty-seven patients undergoing sagittal split ramus osteotomy received passive motion training and muscle endurance training after surgery using the new-developed mouth-opening trainer. The passive motion training began 2-3 days after the removal of inter-maxillary elastraction. The instrument was inserted into the inter-maxillary space for 5 min per time, 3-4 times per day. When the mouth opening reached a range of 20-25 mm, the muscle endurance training initiated. The results of the training were compared with another 20 cases who received the same surgery. RESULTS: The mouth opening of the patients who received muscular rehabilitation achieved the pre-surgical level 4 weeks after surgery [(34.72 ± 3.75) mm], the bite force reached the pre-surgical level 8 weeks after surgery [(231.08 ± 62.52) N], but in the 20 cases without training the mouth opening [(28.42 ± 4.11) mm] in 4 weeks and the bite force in 8 weeks [(210.90 ± 73.40) N] were lower after surgery than before surgery. CONCLUSIONS: The systematic and standard muscle function training, accompanied with the use of the new-developed mouth-opening trainer could improve the functional recovery of the patients who receive sagittal split ramus osteotomies.