Two cases of prostheses for flap protection after buccal mucosal incision.

Here we describe two patients in whom prostheses were applied for flap protection after buccal mucosal incision. In the first case, the patient was a 65-year-old man with a diagnosis of buccal mucosa squamous cell carcinoma (T2N0M0). Left buccal mucosa squamous cell tumor resection and dermoplasty were performed, followed by alveolar ridge augmentation and buccal mucosal graft in the scar area. The carcinoma recurred, however, and left buccal mucosa carcinoma resection was performed, followed by reconstruction surgery using a free forearm flap. After a 12-week healing period, a molar support was constructed on the unaffected side and a protective prosthesis placed on the affected side. Training in ingestion and swallowing were given postoperatively. The patient in the second case was a 62-year-old woman with a diagnosis of buccal mucosa squamous cell carcinoma (T2N1M0). Right buccal mucosa carcinoma resection and supraomohyoid neck dissection were performed, followed by reconstruction surgery using a free forearm flap. A molar support was constructed on the unaffected side and a protective prosthesis placed on the affected side at 5 months postoperatively. Training was given in ingestion and swallowing postoperatively. The prostheses prevented bite wounds to the flaps in the affected areas due to jaw movement during swallowing or speaking. The postoperative courses were uneventful, and the average masticatory score was 92.5 (85, 100), not affecting daily life. The prostheses were placed after reconstruction surgery using free flaps after buccal mucosa squamous cell carcinoma resection. Dysphasia recovered to the preoperative level by dysphasia and pronunciation training in both cases. The postoperative prognosis was favorable, with the prosthesis preventing damage to the flap.

Risk factors for postoperative dysphagia in oral cancer.

With the founding of its Oral Cancer Center at the Ichikawa General Hospital, Tokyo Dental College established a support system for patients and family members that not only provides surgery and other conventional cancer-oriented treatments, but also palliative care, nutritional support, rehabilitation, and discharge support. With this in mind, the present study sought to examine the nature of support for oral cancer patients with postoperative eating and swallowing disorders by investigating these disorders and identifying their risk factors. The study population comprised 75 surviving oral cancer patients (46 men and 29 women) discharged from the Tokyo Dental College Oral Cancer Center following treatment over a 2-year period from April 2009 to March 2011. Risk factors affecting eating and swallowing function were identified by statistical analysis. Mean age of the patients was 67.3±13.7 years. Fifteen patients had stage I cancer, while 25 had stage II, 13 had stage III, and 22 had stage IV. The feeding route at the time of discharge was oral feeding in 74 patients and a combination of oral and gastrostomy tube feeding in 1 patient. The Tokyo Dental College Ichikawa General Hospital has standardized the expert evaluation and rehabilitation of oral cancer patients with eating and swallowing disorders by establishing a multidisciplinary support system from the preoperative stage onwards. In this context, the results of our analysis of factors influencing the ability of oral cancer patients to orally ingest food after treatment suggest that preoperative cancer stage classification, neck dissection, and tracheotomy are all influential factors. Patients affected by these factors require further multidisciplinary treatment, which in turn necessitates more extensive coordination with other medical professionals and community health care providers.

Systemic Inflammatory Response Syndrome and postoperative complications after orthognathic surgery.

Symptoms of Systemic Inflammatory Response Syndrome (SIRS) presenting immediately after surgery have lately been regarded as potential warnings of impending postoperative complications and multiple organ failure. Reports discussing the relationship between operative stress and SIRS are found in the field of digestive surgery, but not in that of oral surgery. Sixty-five patients with jaw deformity who had undergone maxillary and mandibular orthognathic surgery (Le Fort I osteotomy and sagittal splitting ramus osteotomy) between September 2003 and October 2006 were involved in this study. A search based on the SIRS diagnostic criteria resulted in assignment of 33 cases to the SIRS group and 32 cases to the non-SIRS group. Postoperative complications occurred in 27.3% of the SIRS group and 0.0% of the non-SIRS group (p<0.01). In four cases, a postoperative fluctuation in IL-6 level evaluated. These results suggest the importance of careful management of postoperative SIRS patients in preventing complications.

Effects of sex hormones on rat tongue carcinoma induced by 4-nitroquinoline 1-oxide (4NQO).

We investigated the regulatory effects of sex hormones on tongue carcinoma initiated by orally administration 4-nitroquinoline 1-oxide (4NQO) to rats. Animals of either sex were classified into three groups. The male rats in each group received an estrogen administration (Me), orchiectomy (Mor), or both treatments (Me/or) while the female rats also received testosterone administration (Ft), ovariectomy (Fov), or both treatments (Ft/ov). The differences in the carcinogenic progress among these groups were examined by macroscopic and microscopic observation of tongue tissues. The incidence of cancer in the tongue tissue was 100% in the group reinforced with testosterone (testosterone+group) (Ft, Ft/ov, Me) but only 56.0% in the group not reinforced with testosterone (testosterone-group) (Fov, Mor). These findings suggest that sex hormones play a role in the onset of 4NQO-induced tongue carcinoma.

Course of fracture line in sagittal splitting of human mandible.

We performed sagittal splitting osteotomy using fresh, unfixed cadavers. Observation was carried out macroscopically and with light microscopy and 3-dimensionally reconstructed images. The aim of this study was to clarify the relationship between the fracture line and the Haversian canal and Haversian lamellae. Macroscopic observation revealed that the fracture line run through the mandibular angle from the inferior rim of the mandibular ramus towards the posterior rim, passing almost through the center of the ridgeline. Histological observation showed that the fracture line tended to run along the curve of the lamellar structure. The incidence of the fracture line running along the lamellar structure of the Haversian lamellae was approximately 65% (21 cases), and the incidence of the fracture line also cutting across the Haversian canal without passing along the lamellar structure of the Haversian lamellae was approximately 35% (11 cases). Observation of 3-dimensional reconstruction images revealed that the section of Haversian canal near the mandibular angle essentially runs from the mandibular head to the inferior rim of the mandible, and that the fracture plane ran similarly. The direction of an impact-associated bone fracture line is influenced by the structures that constitute the lamellar bone such as Haversian canals, Haversian lamellae and interstitial lamellae, with fracture lines tending to run through those parts of the bone that have a low physical bond strength. This suggests that the ideal direction of action of the bone chisel in sagittal splitting surgery is the one in which no resistance to the path of the Haversian canal is encountered.

Nasolabial flap reconstruction of floor of mouth.

We treated two patients requiring nasolabial flap reconstruction. The first patient was a 75-year-old man with mucoepidermoid carcinoma in the left-side floor of the mouth; requiring resection of the floor of the mouth, partial mandibulectomy, and left supraomohyoid neck dissection. The second patient was a 74-year-old man with recurrent acinic cell carcinoma in the anterior oral floor infiltrating as far as the mandible. This patient required wide excision of the anterior part of the oral cavity, including amputation of the mandible. After tumor resection, both cases had a nasolabial flap reconstruction. The postoperative course of both cases was good; neither postoperative flap necrosis nor infection developed.

Comparison of salivary cytokine levels in oral cancer patients and healthy subjects.

In order to find informative salivary biomarkers specific to oral cancer we examined expression of 4 kinds of cytokine in saliva. Levels of interleukins (IL-1beta, -6, -8) and osteopontin were measured by ELISA using whole saliva samples collected from 19 patients with oral cancer (9 men, 10 women; mean age, 60.9 years) and 20 healthy persons (15 men, 5 women; mean age, 32 years). Expression of the 4 cytokines was higher in patients with oral cancer than in healthy controls. The difference was significant in IL-6, in particular. The results suggest that saliva offers a potential target for a screening test aimed at detection of precancerous lesions.