The use of botulinum toxin type A in masseteric muscle hypertrophy: Long-term effects and lasting improvement

Amaç: Bu çalışmada botulinum toksin A uygulamasının masseter kas kalınlığının azaltılmasındaki uzun dönem etkinliği değerlendirildi. Hastalar ve Yöntemler: Haziran 2007 - Haziran 2008 tarihleri arasında yanakta şişlik yakınması ile başvuran ve benign masseter kas hipertrofisi tanısı ile botulinum toksin tip A enjeksiyonu yapılan 28 hastanın (21 kadın, 7 erkek; ort. yaş 25.5±4.5 yıl; dağılım 20-46 yıl) kayıtları retrospektif olarak değerlendirildi. Tüm hastalarda tanı masseter kasının morfometrik analizi ile konuldu. Botulinum toksin enjeksiyonları altı aylık aralıklarla toplam altı defa yapıldı. Son enjeksiyondan ortalama 13.2 aylık takip sonrasında hastalar geri çağrılarak son kontrol ölçümleri hesaplandı. Bulgular: Ardışık enjeksiyonlar sonrası değerler birbirleriye karşılaştırıldığında, istatistiksel olarak herbir enjeksiyon sonrası masseter kas kalınlığında anlamlı gerileme saptandı (p<0.001). Tedavi bittikten sonra yapılan final ölçümde de bu gerilemenin kalıcı olduğu görüldü. Sonuç: Masseter kas hipertrofisinde botulinum toksin tip A enjeksiyonu güvenilir ve uzun dönem etkinliğe sahip bir yöntemdir.Objectives: In this study, we aimed to evaluate the long-term efficacy of botulinum toxin A injection in reducing the masseter muscle thickness. Patients and Methods: Between 2007 and June 2008, we retrospectively analyzed the data from 28 patients (21 females, 7 males; mean age: 25.5&plusmn;4.5 years; range 20 to 46 years) with benign masseter hypertrophy treated with botulinum toxin A injections. All patients were diagnosed by the morphometric analysis of the masseter muscle. The injections were repeated intermittently every six months and totally for six times. The patients were recalled and the last measurement was performed at a mean follow-up of 13.2 months. Results: The values obtained following consecutive injections were compared and a statistically significant reduction in thickness of masseter muscle thickness after every single injection was found (p&lt;0.001). The final measurement following treatment discontinuation revealed that this reduction was long-lasting. Conclusion: Botulinum toxin A injection is a safe and long-term effective therapy for the masseter muscle hypertrophy

Polymorphisms of the XRCC1 DNA repair gene in head and neck cancer

Inherited polymorphisms in the genes controlling the cell cycle or functioning in the DNA repair mechanisms may impair their function and contribute to genetic susceptibility. Abnormalities in the DNA repair have been reported in head and neck cancer. The XRCC1 gene functions in single-strand break and base excision repair processes. In this study, two polymorphisms of the XRCC1 gene, Arg194Trp and Arg399Gln were investigated in 95 patients with head and neck carcinoma. The polymorphic regions were amplified by PCR followed by digestion with methylation-specific restriction enzymes, and analyzed electrophoretically. Genotype and allele frequencies were calculated, and association with cancer risk or clinical parameters was investigated. No association was observed between the genotypes and head and neck cancer for either polymorphism. Distribution of the alleles did not significantly differ between the patients and the control group. A significant association was only found for the Trp194 allele among the smoking individuals. Our data indicate that the Arg194Trp and Arg399Gln polymorphisms do not confer a significant risk for head and neck carcinogenesis