Oliver Bulik

The impact of Le Fort I advancement and bilateral sagittal split osteotomy setback on ventilation during sleep

The impact of orthognathic surgery for class III malocclusion on ventilation during sleep was examined using a comparison of pre- and post-surgical respiratory parameters. 21 patients with both maxillary hypoplasia and mandibular excess underwent Le Fort I osteotomy and advancement together with bilateral sagittal split osteotomy (BSSO) setback. Respiratory parameters, ECG and position of the body were monitored before surgery and postoperatively after the fixation removal (mean 8.5 months). Average Le Fort I advancement was 4.44 mm, BSSO setback was 4.96 mm. Generally, the orthognathic procedure worsened breathing function during sleep, as reflected in significant increase of index of flow limitations and decrease in oxygen saturation. The posterior airways space decreased to 75% of its original volume, the distance between mandibular plane and hyoid bone increased to 133%. The results indicate that bimaxillary surgery for class III malocclusion increased upper airway resistance. A young person would probably be able to balance such a decline in respiratory function using different adaptive mechanisms, but the potential impact of orthognathic surgery on the upper airways should be incorporated in a treatment plan.

Hemimandibulectomy and therapeutic neck dissection with radiotherapy in the treatment of oral squamous cell carcinoma involving mandible: a critical review of treatment protocol in the years 1994-2004.

This retrospective non-randomized 10-year follow-up study compared 147 patients with squamous cell carcinoma (SCC) of the oral cavity requiring hemimandibulectomy, treated by surgical resection, therapeutic neck dissection and radiotherapy. The 5-year survival rates were compared related to localization, size of the tumour, infiltration of locoregional lymph nodes, distant metastases, histopathological grading, radicality of surgery, and invasion of tumour into the mandible. Occurrence of tumour relapse and its localization was studied. The mean 5-year survival rate was 26%. Patients with SCC of the mandibular alveolar process had higher rates; the lowest rates occurred in SCC of the buccal mucosa. Survival rate was significantly lower with insufficient resection of the tumour (85% relapse). An important number of patients with radical resection died within 3 months of surgery. In almost 55% of the mandibles tumour was not present. In 5% of infiltrated mandibles, dissemination into inferior alveolar nerve was proven. Decreasing survival rate was seen with increasing size of tumour and higher histological grade. Therapeutic neck dissection significantly reduces survival rate and increases the percentage of lymph node relapse. Elective neck dissection should be performed in SCC requiring hemimandibulectomy. Primary reconstruction should reverse the high percentage of postoperative complication arising from increased radicality.

Myosin heavy chain proteins are responsible for the development of obstructive sleep apnea syndrome.

We introduce a hypothesis that obstructive sleep apnea syndrome (OSAS) is primarily caused by an inherited reduced adaptability of upper airway striated muscles such that they cannot maintain patency when there is reduced consciousness (sleep). This reduced ability is caused by a deficiency of the genes for specific myosin heavy chain (MHC) proteins, which are the primary source of muscle adaptability in adults and were initially described in the chewing muscles. The development of OSAS must be linked to problems with striated muscle because affected patients are capable of normal breathing when awake but their respiratory parameters deteriorate during sleep; OSAS must, therefore, be caused by a factor that is voluntarily active during waking but inactive during sleep, and this can only be striated muscle. Congenital or acquired anatomical abnormalities are involved only partially, because OSAS patients with anatomical abnormalities do not begin to snore or to have apneas or hypopneas when lying in bed awake, but begin to do so only when sleeping.

Comparison of arthrocentesis and arthroscopy of the TMJ in the therapy of chronic closed lock

The authors deal with a mini-invasive therapy of the TMJ at chronic closed lock. They compare the efficiency of both arthrocentesis and visual arthroscopic lavage on pain reduction and mouth opening increase. The study evaluates 40 patients in total from the point of view of mouth opening extent and pain severity.