Tülin Oygür

Healing of artificial fenestration defects by seeding of fibroblast-like cells derived from regenerated periodontal ligament in a dog : a preliminary study

The purpose of this study was to assess the seeding of fibroblast-like cells to promote periodontal healing in artificial fenestration defects in a dog. Fibroblast-like cells were cultured by incubating regenerated periodontal ligament tissue, that had been surgically taken, underneath a Teflon membrane. Fenestration defects were surgically induced on the maxillary canine and first molar teeth at a spacing of 5 to 5 mm. Passage 4 cells (2 x 10(5) cells) in autologous blood coagulum were placed on root surfaces in two defects; the remaining two defects were used as controls. Healing was evaluated histomorphometrically on postoperative day 42. The main periodontal healing pattern consisted of connective tissue adaptation in three of the four specimens including one control, with cementum formation at 9-12%; one control specimen that exhibited 100% cementum formation. New bone formation was greater in the cell-seeding group (84%) compared with control (39%). In the cell-seeding group, one specimen exhibited total regeneration of bone (100%); however, the connective tissue located between newly formed bone and the root surface was observed to adapt to the dentin surface, with limited cementum formation. Seeding of cells from periodontal ligament may be promising to promote periodontal regeneration, but needs to be investigated in further studies.

Assessment of periodontal healing by seeding of fibroblast-like cells derived from regenerated periodontal ligament in artificial furcation defects in a dog: a pilot study.

The regeneration of periodontal supporting tissues lost as a result of disease could be accomplished by repopulating the exposed root surfaces with cells originating from periodontal ligament. Thus, we aimed to assess the seeding of cells derived from regenerated periodontal ligament (RPL) to promote the regeneration in artificial furcation defects of a dog. The fibroblast-like cells were obtained by incubating the explants of RPL tissue taken under a teflon (E-PTFE) membrane. Class II furcation defects were induced on the second and fourth mandibular premolars. Control defects were also included on the contralateral side. A suspension of the fourth passage cells (2 x 10(5) cells) in 0.5 mL of autologous blood coagulum was placed over each furcation area. The healing was histomorphometrically evaluated at the 42nd day postoperatively and expressed as percentage. The healing by new connective tissue attachment with cementum formation was found 75% in the cell-seeding defects whereas, it was 71% in controls. Bone formation was found to fill 51% of furcation defects; however, it was 35% of the defects in the control sites. In this pilot study, we suggested that regeneration of furcation defects by cell-seeding technique may be useful, but further studies are needed to determine the outcome of the procedure.

Comparison of Methods for the Extraction of DNA from Formalin-Fixed, Paraffin-Embedded Archival Tissues

Aim: Discussing a protocol involving xylene-ethanol deparaffinization on slides followed by a kit-based extraction that allows for the extraction of high quality DNA from FFPE tissues. Methods: DNA was extracted from the FFPE tissues of 16 randomly selected blocks. Methods involving deparaffinization on slides or tubes, enzyme digestion overnight or for 72 hours and isolation using phenol chloroform method or a silica-based commercial kit were compared in terms of yields, concentrations and the amplifiability. Results: The highest yield of DNA was produced from the samples that were deparaffinized on slides, digested for 72 hours and isolated with a commercial kit. Samples isolated with the phenol-chloroform method produced DNA of lower purity than the samples that were purified with kit. The samples isolated with the commercial kit resulted in better PCR amplification. Conclusion: Silica-based commercial kits and deparaffinized on slides should be considered for DNA extraction from FFPE.

Recurrent osteoblastoma of the mandible : a case report

Osteoblastoma is an uncommon bone tumor most often found in the vertebral column, long bones of the appendicular skeleton, and in the small bones of hands and feet.’ The jaws are rarely involved. Strand-Pettinen et al found 33 cases reported in the literature and added a case of their own.* Although considered a benign neoplasm, osteoblastoma may show an aggressive behavior3 or even sarcomatous transformation4 An aggressive osteoblastoma of the maxilla has been reported.’ An osteoblastoma in the mandible, although rare, can recur6 and may resemble osteosarcoma histologically. A case of osteoblastoma of the mandible that recurred within a year after initial treatment is presented.

Bone reaction to subperiosteally implanted hydroxyapatite/collagen/glycosaminoglycans and coral in the guinea pig

Tissue reactions and new bone formation at 30, 60, and 90 days after the subperiosteal implantation of hydroxyapatite/collagen/glycosaminoglycans and blocks of coral in 18 guinea pigs were evaluated histologically with the use of polarized light and light microscopy. Animals implanted with coral showed new bone formation at each time interval and resorption of coral was observed. Histopathologic evaluation of hydroxyapatite/collagen/glycosaminoglycans implants revealed no evidence of new bone formation and the hydroxyapatite particles were surrounded by fibrous connective tissue.

Recurrent unicystic mural type ameloblastoma in a 9-year-old boy, 8 years follow-up.

Unicystic ameloblastoma is not a rare odontogenic tumor in the pediatric population. A significant care should be given to unicystic ameloblastoma if it has mural invasions due to its local aggressiveness, high recurrence rates and radical management options as in conventional ameloblastoma. Fine needle aspiration (FNA) cytology is a rapid, non-traumatic diagnostic method that provides a required attention prior to surgery. We present an excisionsl biopsy proved FNA diagnosed mural type unicystic ameloblastoma in a 9-year-old child recurred as a solid ameloblastoma after 8 years. When distinctive features of ameloblastoma are known, an accurate diagnosis can be made by FNA cytology, in combination with clinicoradiological findings. This method gives benefit to the patients especially the younger ones both for the pre-operative surgical planning and the post-operative follow-up.

Osteochondroma of the coronoid process of the mandible

A case of osteochondroma of the coronoid process with histological confirmation is presented. CT scan was used for diagnosis and resection was by the intraoral approach.