No abstract

The feasibility of terahertz (THz) imaging at frozen temperature for the clinical application of oral cancer detection was investigated by analyzing seven oral tissues resected from four patients. The size, shape, and internal position of the oral cancers were mapped by THz radiation in the frequency range of 0.2-1.2 THz at -20 °C and 20 °C, and compared with those identified in the histological examination. THz imaging of frozen tissue was found to offer greater sensitivity in distinguishing cancerous areas from surrounding tissue and a larger THz-frequency spectral difference between the oral cancer and normal mucosa than room-temperature THz imaging. A cancerous tumor hidden inside tissue was also detected using this method by observing the THz temporal domain waveform. The histological analysis showed that these findings resulted from cell structure deformations involving the invasion of oral tumor and neoplastic transformations of mucous cells. Therefore, a cytological approach using THz radiation at a frozen temperature might be applied to detect oral cancer.

Biodegradable polymer/ceramic scaffolds can overcome the limitations of conventional ceramic bone substitutes. However, the conventional methods of polymer/ceramic scaffold fabrication often use organic solvents, which might be harmful to cells or tissues. Moreover, scaffolds fabricated with the conventional methods have limited ceramic exposure on the scaffold surface since the polymer solution envelopes the ceramic particles during the fabrication process. In this study, we developed a novel fabrication method for the efficient exposure of ceramic onto the scaffold surface, which would enhance the osteoconductivity and wettability of the scaffold. Poly(D,Llactide-co-glycolide)/nanohydroxyapatite (PLGA/HA) scaffolds were fabricated by the gas foaming and particulate leaching (GF/PL) method without the use of organic solvents. Selective staining of ceramic particles indicated that HA nanoparticles exposed to the scaffold surface were observed more abundantly in the GF/PL scaffold than in the conventional solvent casting and particulate leaching (SC/PL) scaffold. Both types of scaffolds were implanted to critical size defects in rat skulls for 8 weeks. The GF/PL scaffolds exhibited significantly enhanced bone regeneration when compared with the SC/PL scaffolds. Histological analyses and microcomputed tomography of the regenerated tissues showed that bone formation was more extensive on the GF/PL scaffolds than on the SC/PL scaffolds. Compared with the SC/PL scaffolds, the enhanced bone formation on the GF/PL scaffolds may result from the higher exposure of HA nanoparticles to the scaffold surface. These results show that the biodegradable polymer/ceramic composite scaffolds fabricated with the novel GF/PL method can enhance bone regeneration compared with those fabricated with the conventional SC/PL method.

The RAB height did not increase crestal bone loss or reduce the success rate of the implants and associated prostheses. The crestal approach should be considered a viable technique for use in patients with residual bone height of ≤ 4 mm and merits further evaluation.

ObjectivesIdiopathic bone cavity (IBC) is an uncommon intra-osseous cavity of unknown etiology. Clinical features of IBC are not well known and treatment modalities of IBC are controversial. The purpose of this study was to investigate the clinical characteristics of 27 IBC patients who underwent surgical exploration.Materials and MethodsA total of 27 consecutive patients who underwent surgery due to a jaw bone cavity from April 2006 to February 2016 were included in this study. Nine male and 18 female patients were enrolled. Patients were examined retrospectively regarding primary site, history of trauma, graft material, radiographic size of the lesion, presence of interdental scalloping, erosion of the inferior border of the mandible, complications, results of bone graft, and recurrence.ResultsFemale dominance was found. Maxillary lesion was found in one patient, and bilateral posterior mandibular lesions were found in two patients. The other patients showed a single mandibular lesion. The posterior mandible (24 cases) was the most common site of IBC, followed by the anterior mandible (5 cases). Two patients with anterior mandibular lesion reported history of trauma due to car accident, while the others denied any trauma history. Radiographic cystic cavity length over 30 mm was found in 10 patients. Seven patients showed erosion of the mandibular inferior border. The operations performed were surgical exploration, curettage, and bone or collagen graft. One bilateral IBC patient showed recurrence of the lesion during follow-up. Grafted bone was integrated into the native mandibular bone without infection. One patient reported necrosis of the mandibular incisor pulp after operation.ConclusionDifferential diagnosis of IBC is difficult, and IBC is often confused with periapical cyst. Surgical exploration and bone graft are recommended for treating IBC. Endodontic treatment of involved teeth should be evaluated before operation. Bone graft is recommended to reduce the healing period.

Sinus lifting with simultaneous implant placement could be used to treat atrophic maxilla in patients with minimal RABH when initial stability could be obtained by using taper designed implants with surgical techniques. Smoking is a possible factor for implant failure. Membrane perforation did not have an adverse effect on implant success if the membrane was repaired with absorbable membrane and fibrin glue.

Unusual jaw necrosis after dental implant surgery might be related with oral and/or intravenous bisphosphonates. Wide resection of necrotic bone, collagen graft, and primary closure are key factors for successful healing.

Transoral periosteal thyroidectomy could be feasible and safe.