Bone Scan "Hot Spot" at the Superior Lateral Orbital Margin Fronto-zygomatic Suture Uptake Characterized with Tc-99m MDP SPECT/CT.

Findings of a solitary "hot spot" at the superior lateral orbital margin on bone scan scintigraphy is not uncommonly seen, and is often dismissed as a benign lesion. However, the exact etiology is indeterminate. We present two cases in which hybrid single photon emission computed tomography/computed tomography imaging was able to characterize and localize this uptake, demonstrating correlation to the right fronto-zygomatic suture.

Differentiating osteoradionecrosis from nasopharyngeal carcinoma tumour recurrence using 99Tcm-sestamibi SPECT/CT.

Osteoradionecrosis (ORN) of the base of skull is a known complication of external beam radiotherapy in the treatment of nasopharyngeal carcinoma, and is widely believed to be sequelae of radiation-induced endarteritis, leading to cellular death and fibrosis. Differentiating ORN from tumour recurrence is challenging and has direct clinical implications. We present a case where (99)Tc(m)-sestamibi SPECT/CT was used to differentiate ORN from tumour recurrence and in which prior imaging using bone scintigraphy and fluorodeoxyglucose PET/CT were equivocal.

Periodontal maintenance.

The main goal of periodontal therapy is to establish an oral environment compatible with periodontal health by the physical disruption of the plaque biofilm and adjunctive chemical means if required. Implicit in this objective is the ongoing requirement of detection and interception of new and recurrent disease, which continues at selected intervals for the life of the dentition after the initial ("active") phase of periodontal treatment. This concept of ongoing periodontal maintenance therapy has been embraced as the mandatory requirement for favourable periodontal outcomes based on institutional clinical trials and in practice-based studies in various parts of the world. This review examines the ramifications of periodontal maintenance therapy based upon a multi-level assessment of logistic issues and risk factors at three levels: (1) The patient level - treatment time; patient attendance compliance; and homecare measures, antiseptics/antibiotics and smoking. (2) The level of the individual tooth - tooth loss; and evaluation of success versus survival. (3) The level of each tooth surface ("site") - probing depth, loss of attachment and bleeding on probing; and changes in clinical attachment levels. In spite of the diversity of studies conducted, there is agreement on the efficacy of periodontal maintenance therapy when compared with studies on untreated populations and in treated cases that were not maintained.

Augmentation of angiogenic and endothelial associated gene expression by EDM50 in human chorion-derived stem cells.

The objective of this study was to investigate the angiogenic potential of human chorion-derived stem cells (CDSC) cultured in medium containing bFGF and VEGF (EDM50). Total RNA was extracted from cells cultured in FD+10% FBS and EDM50. Quantitative RT-PCR was carried out to score the differential mRNA expression of genes involve in angiogenesis and endothelial differentiation. Our finding demonstrated that all angiogenic and endothelial associated genes were expressed higher in EDM50. Expression level of ANG-1, eNOS and VEGFR2 were significantly higher in EDM50 compared to FD+10% FBS. Our results suggested that human CDSC cultured in EDM50 can be used for angiogenesis purpose in regenerative medicine.

Quantitative RT PCR approach to evaluate the neurogenic and gliagenic gene expression of cultured human amniotic epithelial cells.

The aim of the study is to determine the neuronal and glial gene expression of cultured human amniotic epithelial cells (HAECs) in serial passages. HAECs obtained from human term placentae were cultured in F12:DMEM (1:1) + 10% FBS +10ng/ml EGF in serial passages. Quantitative RT-PCR was used to assess the gene expression analysis. The results showed that the cultured HAECs expressed the neural stem cell genes (Nestin, NSE and Vimentin), mature neuronal genes (TH, MAP-2, beta-III-tubulin and NFM) and glial genes (CNPase, MBP and Olig). These neural stem cell genes increased with serial passages while the genes expression for mature neuronal and glial cells were downregulated. These results suggested that HAECs may promote or involve in neurogenesis and gliagenesis.

The stemness gene expression of cultured human amniotic epithelial cells in serial passages.

The aim of the study is to evaluate the stemness gene expression of cultured human amniotic epithelial cells (HAECs) in serial passages. HAECs obtained from human term placentae were cultured in F12:DMEM(1:1) + 10% FBS +10ng/ml EGF in serial passages (P0, P1, P2 and P4). Quantitative RT-PCR was used to assess the gene expression analysis. The results showed that cultured HAECs expressed and downregulated the stemness genes expression for Oct-4, Sox-2, Nanog3, FGF4, Rex-1, FZD-9, BST-1 ABCG2. However, vimentin and nestin gene expression were upregulated. The results suggested that cultured HAECs may have pluripotent and multipotent properties.

Upregulation of SOX-2, FZD9, Nestin, OCT-4 and FGF-4 expression in human chorion derived-stem cells after angiogenic induction.

Angiogenic induction was made to promote angiogenesis by differentiating stem cells towards endothelial cells. However, the stemness property of induced cells has not been revealed yet. Hence, we aim to evaluate the differential mRNA expression of stemness genes in human chorion-derived stem cells (CDSC) after being cultured in EDM50 comprised bFGF and VEGF. Results indicated that CDSC cultured in EMD50 expressed significantly higher mRNA level of Sox-2, FZD9, BST-1 and Nestin. In addition Oct-4, FGF-4 and ABCG-2 were also upregulated. Our finding suggested that CDSC after angiogenic induction enhanced its stem cell properties. This could be contributed for the mechanism of stem cell therapy in ischemic problem.

The role of serum insulin-like growth factor I (IGF-I) in neonatal outcome.

AIMS: To determine the role of serum insulin-like growth factor I (IGF-I) in predicting the occurrence of septal hypertrophic cardiomyopathy in infants of mothers with diabetes. METHODS/MATERIALS: In this prospective study, 100 pregnant women (50 with diabetes and 50 controls), matched for age and race, were studied. One intrapartum blood sample was taken at 28 weeks of gestation from both groups of mothers and another sample at delivery. All samples were analysed for maternal IGF-I by an enzyme linked immunosorbent assay method. A chest radiograph and an electrocardiogram were performed on the babies of the mothers with diabetes within the first 24 hours of life. An echocardiogram was performed in the first 3 days of life to look for septal hypertrophy and to measure the myocardial thickness. RESULTS: In the six cases of neonatal septal hypertrophic cardiomyopathy, all the mothers had greatly raised IGF-I concentrations of more than 400 ng/ml at the time of delivery compared with a mean (SD) of 302 (25) ng/ml in control mothers. CONCLUSIONS: In the present study a crude analysis revealed that increased IGF-I concentrations correlate with neonatal septal hypertrophic cardiomyopathy.

Tissue regeneration adjacent to titanium implants placed with simultaneous transposition of the inferior dental nerve: a study in dogs.

Transposition of the inferior alveolar nerve was performed in an experimental dog model. Four adult greyhounds were used in the study. Surgical transposition of the nerve was made bilaterally, and 3 implants were placed on each side while the nerve was lateralized. On one side, the nerve was repositioned in contact with the implants, while on the contralateral side a resorbable membrane was positioned between the implant surface and the neurovascular bundle. Histologic section after 4 months of healing showed an intimate contact between implants and nerve tissue in all cases without an interpositional membrane, in contrast to cases with membranes. Histomorphometric measurements of the distance between the implants and the nerve tissue showed that the membrane side had a considerably larger distance between the implant and the nerve, although not with concomitant bone formation.

Syntaxin 12, a member of the syntaxin family localized to the endosome.

We have cloned a new member of the syntaxin family of proteins. The open reading frame encodes a polypeptide of 272 amino acids with potential coiled-coil domains and a C-terminal hydrophobic tail. Northern blot analysis showed that the transcript is fairly ubiquitous. A soluble recombinant form of the polypeptide without the hydrophobic region binds to alpha-SNAP (soluble N-ethylmaleimide-sensitive factor attachment protein) and syndet/SNAP-23 in vitro. Polyclonal antibody raised against the recombinant protein recognized a 39-kDa protein in the membrane fraction of cell lysates. Indirect immunofluorescence studies using the polyclonal antibody showed that the protein is localized to intracellular membrane structures. Selective permeabilization studies with digitonin and saponin indicate that the epitope(s) recognized by the antibody is expose to the cytoplasm, consistent with the predicted orientation characteristic of SNAP receptor molecules. Morphological alterations of the staining pattern of the protein with brefeldin A and wortmannin treatment indicate that the protein is localize to the endosome. The cDNA we have cloned apparently corresponded to three previously described expressed sequence tags named as syntaxins 12, 13, and 14, respectively. We therefore propose to retain the name syntaxin 12 for this protein.

Syntaxin 10: a member of the syntaxin family localized to the trans-Golgi network.

We have cloned a new member of the syntaxin family of proteins, designated human syntaxin 10 (hsyn10). The open reading frame encodes a polypeptide of 249 amino acids with potential coiled-coil domains and a carboxy-terminal hydrophobic tail. hsyn10 is particularly homologous to the recently reported rat syntaxin 6 (about 60% identity). Northern blot analysis showed that the transcript is enriched in the heart, skeletal muscles and pancreas. Indirect immunofluorescence studies using polyclonal antibodies raised against recombinant protein showed that the protein is localized to intracellular membrane structures, with perinuclear staining patterns colocalising well with the Golgi SNARE GS28. Morphological alterations of the staining pattern of the protein with brefeldin A but not wortmannin treatment indicate that the protein is localize to the trans-Golgi network.

Molecular cloning and localization of human syntaxin 16, a member of the syntaxin family of SNARE proteins.

We have cloned a new member of the syntaxin family of proteins, designated human syntaxin 16 (hsyn16). The open reading frame encodes a polypeptide of 307 amino acids with potential coiled-coil domains and a carboxy-terminal hydrophobic tail, which is characteristic of other members of the syntaxin family. The encoded polypeptide bears sequence homology to known syntaxin molecules. Northern blot analysis revealed a single transcript that is fairly ubiquitous, being slightly more enriched in heart and pancreas. Indirect immunofluorescence localised myc-tagged hsyn16 (myc-hsyn16) to the Golgi apparatus, colocalizing well with lens culinaris agglutinin, an established Golgi marker, as well as with other Golgi SNAREs such as GS28 and syntaxin 5. Myc-hsyn16 is redistributed to the endoplasmic reticulum upon brefeldin A treatment, indicating that it is localised to the Golgi stack. The ubiquitous expression and Golgi localization of hsy16 suggest that it is involved in a vesicular transport step within the organelle.

Fit discrimination of implant-supported fixed partial dentures fabricated from implant level impressions made at stage I surgery.

STATEMENT OF PROBLEM: The implant level impression can shorten the overall time frame of implant treatment. PURPOSE OF STUDY: The purpose of this study was to analyze the accuracy of fixed partial dentures constructed from impressions taken at implant installation surgery in partially edentulous dogs. The study compared the fit of welded titanium fixed partial dentures with that of cast gold alloy fixed partial dentures. MATERIAL AND METHODS: Three implants were placed on each side of the mandible in six adult greyhound dogs during stage I surgery. Impressions were taken of the implant positional relationships and two types of fixed partial dentures were fabricated for each side of the mandible. Stage II surgery was performed after 3 months. RESULTS: Both types of fixed partial dentures compared favorably with the fit of implant-supported fixed partial dentures in the edentulous jaw or traditional cast fixed partial denture frameworks. CONCLUSIONS: Impressions taken at implant installation surgery provide a valid transfer of information for the laboratory fabrication of the final restoration when the implants are placed to fulfill the requirements of primary stability.

Tissue regeneration in bony defects adjacent to immediately loaded titanium implants placed into extraction sockets: a study in dogs.

In this study of six greyhound mandibles, 24 implants were placed into extraction sockets. Eighteen of the implants were connected with abutments and immediately placed into normal function, and the remaining six submerged implants served as controls. At placement, dehiscence areas were created adjacent to 12 of the implants to study bone regeneration in extended membrane-protected defects. Six of the defects were covered with expanded polytetrafluoroethylene membranes, and six of the defects were augmented with autologous bone grafts and covered with expanded polytetrafluoroethylene material. The clinical and radiographic evaluations demonstrated that all implants achieved functional osseointegration and no implants were lost. Implant sites where membranes were used to regenerate bone over dehiscence defects demonstrated a high rate of membrane exposure and variable response to treatment. On completion of the study at 16 weeks, histomorphometric analysis demonstrated osseointegration with direct bone-to-implant contact for all implants, although the percentage of contact varied considerably. Histomorphometry indicates that the quality of osseointegration may be less favorable than the clinical and radiographic result would suggest.

Secondary alveolar bone grafting--five-year periodontal and radiographic evaluation in 100 consecutive cases.

A prospective study of secondary alveolar bone grafting based on the Norwegian (Oslo) team approach has been conducted by the CLP Unit at the Princess Margaret Hospital for Children in Perth, Australia, since 1982. The 5-year results of 100 consecutive cases of uni- and bilateral cases are presented according to periodontal and radiographic parameters of tooth support. The vast majority of cases grafted (98%) resulted in the eventual eruption of the cleft side cuspid/lateral incisor within acceptable parameters of tooth support. The results confirm the predictability of this safe procedure when utilized within a strict clinical protocol involving the whole CLP team.

New ideas and advancing technologies in periodontology: surgical options with advancing technologies.

Extensive clinical studies over the last two decades have documented the effectiveness of both non-surgical and surgical periodontal therapy. When deemed necessary, surgery is usually performed as an elective phase of therapy, within a programme of ongoing maintenance care. Traditionally surgical therapy has been aimed at the treatment of the periodontal pocket by resective procedures. However, research has now focused on reconstructive surgery, with the objective of regenerating the structure of the lost periodontium (cementum, periodontal ligament and also alveolar bone). With advancing technology, materials and surgical modalities that have been advocated to facilitate periodontal reconstruction fall into the following main categories: 1. Chemical and biochemical conditioning agents, e.g. citric acid, fibronectin, tetracycline, growth and differentiation factors. 2. Transplants of autogenous or allogeneic (osteogenic or osteoinductive) materials, e.g. osseous coagulum, decalcified freeze-dried bone allograft. 3. Implants of alloplastic (osteoconductive) 'filler' materials, e.g. hydroxyapatite, tricalcium phosphate. 4. Guided tissue regeneration (GTR) utilising membranes, e.g. Teflon (e-PTFE), collagen, polylactic acid. 5. Combined techniques, e.g. GTR and allograft/alloplast. The scientific evaluation and the role of these reconstructive surgical procedures in contemporary dental practice is discussed in this paper.

A proposal for voluntary continuing dental education accreditation.

The paper proposes a simple method of voluntary continuing dental education accreditation for dentists. It is suggested that the Australian Dental Association should adopt a positive role in promoting a method of accreditation for its members. The reasons for such a scheme are discussed in the light of the current scrutiny directed at the professions on this important issue.

Patient attendance compliance in periodontal therapy.

Attendance compliance of patients presenting for periodontal therapy during one calendar year at two practice locations (Perth, Western Australia and Darwin, Northern Territory) was observed over a period of three to four years, depending on whether the patients were seen in the earlier or latter part of the initial year. Both venues (full-time practice and visiting practice every quarter) gave very similar results, of around 10 per cent of patients who dropped out after initial consultation, without commencing treatment. As well, both venues showed a similar trend of subsequent patient 'attrition' after the initial phase of treatment, with the retention of approximately 40 per cent of the original group of patients after three to four years. Of these, a very high proportion (90 per cent) were totally compliant with maintenance recall appointments.

Survey of continuing dental education attendance in Western Australia.

A survey of attendance at continuing dental education courses convened by the University Postgraduate Dental Education Committee, University of Western Australia, and the Australian Dental Association. Western Australian Branch was collated for one calendar year. Attendances were compared relating to the number of dentists registered in the State, ADA membership, metropolitan versus rural dentists and the number of courses attended. The mandatory and voluntary options for continuing dental education are discussed in the light of the survey findings.