Bone-patellar tendon-bone autograft maturation is superior to double-bundle hamstring tendon autograft maturation following anatomical anterior cruciate ligament reconstruction.

PURPOSE: The primary purpose of this study was to evaluate the second-look arthroscopic findings 1 year postoperatively and magnetic resonance imaging (MRI) findings 2 years after anterior cruciate ligament reconstruction (ACLR) using bone-patellar tendon-bone autograft (BTB) or hamstring tendon autograft (HT). Secondary purpose included clinical results from physical examination, including range of motion, Lachman test, pivot shift test, and knee anterior laxity evaluation, and the clinical score for subjective evaluations at 2 years after surgery. METHODS: Between 2015 and 2018, 75 patients with primary ACL injuries were divided into either the BTB group (n = 30) or HT group (n = 45). When using HT, an anatomical double-bundle ACLR was performed. BTB was indicated for athletes with sufficient motivation to return to sporting activity. Graft maturation on second-look arthroscopy was scored in terms of synovial coverage and revascularization. All participants underwent postoperative MRI evaluation 2 years postoperatively. The signal intensity (SI) characteristics of the reconstructed graft were evaluated using oblique axial proton density-weighted MR imaging (PDWI) perpendicular to the grafts. The signal/noise quotient (SNQ) was calculated to quantitatively determine the normalized SI. For clinical evaluation, the Lachman test, pivot shift test, KT-2000 evaluation, Lysholm score, and Knee injury and Osteoarthritis Outcome Score (KOOS) were used. RESULTS: Arthroscopic findings showed that the graft maturation score in the BTB group (3.6 ± 0.7) was significantly greater than that in the anteromedial bundle (AMB; 2.9 ± 0.2, p = 0.02) and posterolateral bundle (PLB; 2.0 ± 0.9, p = 0.001) in the HT group. The mean MRI-SNQs were as follows: BTB, 2.3 ± 0.5; AMB, 2.9 ± 0.9; and PLB, 4.1 ± 1.1. There were significant differences between BTB, AMB, and PLB (BTB and AMB: p = 0.04, BTB and PLB: p = 0.003, AMB and PLB: p = 0.03). Second-look arthroscopic maturation score and MRI-SNQ value significantly correlated for BTB, AMB, and PLB. No significant differences were detected in clinical scores. There was a significant difference (p = 0.02) in the knee laxity evaluation (BTB: 0.9 ± 1.1 mm; HT: 2.0 ± 1.9 mm). CONCLUSION: BTB maturation is superior to that of double-bundle HT based on morphological and MRI evaluations following anatomical ACLR, although no significant differences were found in clinical scores. Regarding clinical relevance, the advantages of BTB may help clinicians decide on using the autograft option for athletes with higher motivation to return to sporting activity because significant differences were observed in morphological evaluation, MRI assessment, and knee anterior laxity evaluation between BTB and double-bundle HT. LEVEL OF EVIDENCE: Level IV.

Joint effusion at 6 months is a significant predictor of joint effusion 1 year after anterior cruciate ligament reconstruction.

PURPOSE: This study aimed to assess the risk factors for prolonged joint effusion in patients undergoing double-bundle anterior cruciate ligament reconstruction (ACLR). METHODS: In total, 160 patients who underwent primary ACLR using autograft hamstring between 2015 and 2018 were retrospectively reviewed. Joint effusion was defined as any grade ≥ 2 (range, 0-3) according to the MRI Osteoarthritis Knee Score (MOAKS). Univariate and multivariate logistic regression analyses were performed. RESULTS: The median age of the patients was 25 years (range 14-68 years) at the time of the surgery; there were 89 women and 71 men. At 1 year, 46 (28.8%) patients experienced knee joint effusion, as defined by the MOAKS. Univariate analysis revealed that age, preoperative Kellgren-Lawrence (K-L) grade, and joint effusion at 6 months were significantly associated with joint effusion at 1 year. In the multivariate analysis, joint effusion at 6 months was significantly associated with joint effusion at 1 year (odds ratio, 68.0; 95% confidence interval, 22.1-209.4). No significant difference in the Lysholm scores was observed between patients with and without joint effusion at 1 year (n.s.). CONCLUSIONS: Joint effusion at 6 months was significantly associated with joint effusion 1 year after ACLR. LEVEL OF EVIDENCE: III.

Femoral nerve versus adductor canal block for early postoperative pain control and knee function after anterior cruciate ligament reconstruction with hamstring autografts: a prospective single-blind randomised controlled trial.

INTRODUCTION: The optimal pain management strategy for postoperative pain after anterior cruciate ligament reconstruction (ACLR) remains unclear. This study compared femoral nerve block (FNB) and adductor canal block (ACB) for pain management of early postoperative pain, knee function, and recovery of activity of daily living (ADL) after ACLR using hamstring autografts. MATERIAL AND METHODS: In this prospective, single-blind, randomised controlled trial, 64 patients aged 12-56 years who underwent anatomical double-bundle ACLR with a hamstring autograft between August 2019 and May 2020 were randomised to undergo preoperative FNB (n = 32) or ACB (n = 32). The peripheral nerve block was performed by a single experienced anaesthesiologist under ultrasound guidance. The primary outcomes were postoperative pain as evaluated using the visual analogue scale (VAS) at 3, 6, 12, 24, and 48 h postoperatively and the need for pain relief. The secondary outcome was knee function, including the recovery of range of motion, contraction of the vastus medialis, and stable walking with a double-crutch (ADL), as evaluated by blinded physical therapists. RESULTS: There were no significant differences in patient demographics between the two groups. The VAS scores, need for pain relief, knee function, and ADL did not significantly differ between the groups. CONCLUSION: FNB and ACB provided comparable outcomes related to early postoperative pain, knee function, and ADL after double-bundle ACLR using hamstring autografts. Further research is necessary to evaluate the mid- to long-term effect of each block on recovery of knee function and ADL. LEVEL OF EVIDENCE: I.

Surgical Management of Median Cleft Lip Extending as Far as Alveolus Using Bone Grafting.

Median clefts, which run through the midline of the upper lip, and alveolus are considered a type of craniofacial cleft. A Tessier number 0 median cleft lip is the rarest, and there are few reports concerning its surgical management. Here, we describe the case of a 6-year-old boy who presented at our hospital with a median cleft and alveolus of the upper lip with a shortened bifid frenulum. Inverted-V and Z-plasty incisions were performed for the median cleft and iliac bone grafting for the midline alveolus. At 1 year 5 months later, the postoperative course was uneventful, and proper approximation of the orbicularis oris muscle and vermilion were achieved, with a symmetrical Cupid's bow and labial tubercle and philtrum.

Morphologic Evaluation for Safe Le Fort I Osteotomy in Cleft Lip and Palate.

OBJECTIVE: The present study aimed to determine the structure and morphology of the maxilla in patients with cleft lip and palate to ensure safe Le Fort I osteotomy. PATIENTS: A total of 34 sides of 17 patients with unilateral cleft lip and palate (nonsyndromic cases) were included in this study. The control group included 10 sides of 5 patients who exhibited skeletal mandibular protrusion without malformation. METHODS: Finite element analysis was performed to examine the distribution of occlusal force over the maxilla, and continuous 3-dimensional measurement was performed at the sites of stress concentration. RESULTS: In patients with cleft lip and palate, bones at the lateral border of the piriform aperture and the anterior wall of the maxillary sinus were significantly thicker than those in controls ( P < .05). Furthermore, the attachment of the pterygomaxillary junction was wider and thicker ( P < .05), and the anterior distance to the descending palatine artery was shorter ( P < .01) in patients with cleft lip and palate than in controls. Our results further indicated that alveolar bone grafting may significantly influence bone thickness and the attachment state of the pterygomaxillary junction. CONCLUSIONS: Our results suggest that the complications of LFI can be reduced in patients with cleft lip and palate by ensuring proper understanding of each patient's maxillary anatomy and bone thickness, as well as the location of the descending palatine artery and the attachment state of the pterygomaxillary junction.

Autotransplantation or replantation of cryopreserved teeth: a case series and literature review.

BACKGROUND: The aim of this report was to evaluate the outcome of autotransplantation or replantation of cryopreserved teeth clinically and radiographically. Donor teeth were slowly frozen in a controlled-rate freezer using 5% dimethylsulfoxide (DMSO) and 6% hydroxyethyl starch (HES) as protectants. Seven cryopreserved teeth, with duration of storage ranging from 4 to 36 months, were autotransplanted or replanted at Niigata University Medical and Dental Hospital. Endodontic treatment involving root canal debridement followed by interim root canal filling with calcium hydroxide was started 3 weeks after the operation and continued with replacement of the calcium hydroxide filling at 2-week to 3-month intervals. Three transplants showed periodontal regeneration clinically and radiographically, whereas replacement root resorption was observed in the remaining transplants. From the results, it can be concluded that cryopreserved tooth autotransplantation has potential for clinical use; however, the risk of replacement root resorption remains.

Distinct expression patterns and roles of aldehyde dehydrogenases in normal oral mucosa keratinocytes: differential inhibitory effects of a pharmacological inhibitor and RNAi-mediated knockdown on cellular phenotype and epithelial morphology.

Aldehyde dehydrogenases (ALDHs), enzymes responsible for detoxification and retinoic acid biosynthesis, are considered a potent functional stem cell marker of normal and malignant cells in many tissues. To date, however, there are no available data on ALDH distributions and functions in oral mucosa. This study aims to clarify the levels and types of ALDH expression using immunohistochemistry with accompanying mRNA expression as well as an ALDEFLUOR assay, and to assess phenotypic and histological changes after manipulation of the ALDH activity of oral keratinocytes to increase the potency of a tissue-engineered oral mucosa by a specific ALDH inhibitor, diethylaminobenzaldehyde (DEAB), together with small interfering RNA of ALDH1A3 and ALDH3A1. Results showed the mRNA and cytoplasmic protein expression of ALDH1A3 and ALDH3A1 to be mostly localized in the upper suprabasal layer although no ALDH1A1 immunoreaction was detected throughout the epithelium. Oral keratinocytes with high ALDH activity exhibited a profile of differentiating cells. By pharmacological inhibition, the phenotypic analysis revealed the proliferating cell-population shifting to a more quiescent state compared with untreated cells. Furthermore, a well-structured epithelial layer showing a normal differentiation pattern and a decrease in Ki-67 immunopositive basal cells was developed by DEAB incubation, suggesting a slower turnover rate efficient to maintain undifferentiated cells. Histological findings of a regenerated oral epithelium by ALDH1A3 siRNA were similar to those when treated with DEAB while ALDH3A1 siRNA eradicated the epithelial regenerative capacity. These observations suggest the effects of phenotypic and morphological alterations by DEAB on oral keratinocytes are mainly consequent to the inhibition of ALDH1A3 activity.

Keratin 10-positive orthokeratotic dysplasia: a new leucoplakia-type precancerous entity of the oral mucosa.

AIMS: We investigated a group of oral mucosal lesions with characteristic hyperorthokeratotic foci, which we termed orthokeratotic dysplasia (OKD), to determine if it could be identified as a distinct histopathological entity. METHODS AND RESULTS: We screened 282 surgical specimens from 200 patients with oral leucoplakia-type squamous cell carcinoma (SCC) or carcinoma in situ (CIS). OKD was defined as an oral mucosal lesional focus in which hyperorthokeratosis was predominant in the presence of the granular cell layer. A total of 84 OKD foci from 62 cases found among the 200 SCC/CIS cases were analysed. According to its rete ridge shapes, OKD was classified into three subtypes: flat (14.3%), leg (63.1%) and intermediate (22.6%). Eighty per cent of OKD foci were adjacent to the main foci of SCC or CIS, and they were demarcated sharply from each other. Most of the OKD constituent cells were immunopositive for keratin 10, but not for keratins 13, 17 or 19. Numbers of Ki-67-positive cells in the first basal layer were greater in OKD than in normal epithelia. CONCLUSIONS: The findings indicate that OKD is a distinct variant of epithelial dysplasia related to malignancies, and hence that it is important to recognize its existence.

Keratinocytes of tissue-engineered human oral mucosa promote re-epithelialization after intraoral grafting in athymic mice.

PURPOSE: The objective of this study was to investigate the role of grafted oral keratinocytes in a transplanted ex vivo-produced oral mucosa equivalent (EVPOME) in the regeneration and/or healing process of the oral mucosa at the recipient site. MATERIALS AND METHODS: The EVPOME was developed in a serum-free defined culture system without a feeder layer. EVPOME is composed of a stratified layer of human oral keratinocytes that are seeded onto a human cadaveric dermis, AlloDerm (LifeCell, Branchburg, NJ). Intraorally grafted EVPOMEs in athymic mice (BALB/c) were excised, contiguous with the surrounding oral mucosa, on days 5, 7, 14, and 21 after grafting. Serial sections were stained with hematoxylin-eosin and immunohistochemically analyzed for cytokeratin 17 (CK17) expression to distinguish the human-cultured EVPOME epithelial keratinocytes from murine oral keratinocytes. RESULTS: All EVPOME epithelial cells showed intense immunoreactivity for CK17, whereas mouse buccal mucosal epithelial cells did not show CK17 immunoreactivity. The grafted EVPOME maintained a stratified epithelial layer for up to 5 days after grafting. By day 7 after grafting, a portion of the EVPOME epithelial layer peeled away from the AlloDerm, and a thin, CK17-immunonegative epithelial layer extended from the adjacent thick epithelial layer of the mouse and contacted the CK17-immunopositive EVPOME epithelium. From days 14 to 21 after grafting, the stratification of the CK17-immunonegative continuous mouse epithelium increased compared with earlier time points and showed a similar appearance to the epithelium of the adjacent mouse mucosa. In contrast, no epithelial coverage of the AlloDerm that was grafted without keratinocytes was observed for up to 21 days after grafting. The grafted AlloDerm without cells resulted in tissue necrosis that was accompanied by a dramatic infiltration of inflammatory cells by day 14. CONCLUSIONS: These findings suggest that grafting of EVPOME with viable oral keratinocytes onto an intraoral mucosal wound plays an active role in promotion of re-epithelialization of the oral wound during the subsequent healing process.

Enhanced expression of podoplanin in oral carcinomas in situ and squamous cell carcinomas.

OBJECTIVE: Podoplanin, a known lymphatic endothelial cell marker, has been reported to be expressed in various types of cancer. To elucidate the expression of podoplanin in precancerous lesions, we examined the immunohistochemical profiles of podoplanin in oral squamous epithelial lesions. METHOD: We studied a total of 298 foci of squamous cell carcinoma (SCC), carcinoma in situ (CIS), epithelial dysplasia, and hyperplastic and/or normal epithelial lesions by immunohistochemistry using D2-40. RESULTS: There was no positivity for podoplanin in normal or hyperplastic epithelia, while all of the CIS and SCC foci stained positive. Approximately one third of the mild dysplasia foci (10 of 36 foci, 28%) and 80% of moderate dysplasia foci (78/98) showed grade 1 positive reactions (positive only in the 1st layer). Grade 2 reactions (up to 4th layer) were seen in 4 of 98 moderate dysplasia foci (4%), 29 of 74 CIS foci (39%), and 3 of 30 SCC foci (10%). Grade 3 reactions (to more than 5th layer) were found in 35 (47%) CIS foci and 26 (87%) SCC foci. CONCLUSIONS: The relationship between the present histological categorization and podoplanin grade was statistically significant. D2-40 expression is considered to be related to the severity of oral precancerous lesions.

Long-term observation of autotransplanted teeth with complete root formation in orthodontic patients.

INTRODUCTION: The objective of this investigation was to examine the factors influencing the long-term prognosis of autotransplanted teeth with complete root formation. METHODS: Thirty-eight teeth, autotransplanted in 32 patients, were examined more than 6 years after transplantation. Periodontal health, condition of restoration, mobility, occlusal contact, level of gingival margin, and course of orthodontic movement were investigated clinically and with radiographs. RESULTS: More than 6 years after autotransplanation, 33 teeth survived in 27 patients. The survival rate was 86.8% (mean observation time, 9.2 years). Abnormal findings were observed in 9 teeth, so the success rate was 63.1%. An inadequate root filling tended to give rise to abnormal findings. CONCLUSIONS: The success of autotransplantation of a tooth with complete root formation is affected by the quality of root filling. When possible, clinicians should consider autotransplantation before root formation is complete.

Immunohistochemical detection of nestin in the periodontal Ruffini endings of the rat incisor.

Nestin is an intermediate filament which was first identified in neuroepithelial stem cells. This expression has also been reported in restricted locations in adults. Previous studies have suggested that the periodontal Ruffini endings remain immature in nature even in adulthood. The present study reports on a characteristic expression of immunoreaction for nestin in the periodontal Ruffini endings during postnatal development. RT-PCR analysis detected nestin mRNA in a reverse transcripted cDNA sample from both the rat trigeminal ganglion and periodontal ligament. The nestin immunoreaction existed in the periodontal ligament at postnatal day 3 (PO 3 days), when many spindle-shaped Schwann cells were positive for nestin immunoreaction. At PO 1 week, when periodontal nerve fibers displayed a dendritic fashion, the round cells came to show the nestin immunoreaction. These immunopositive cells were also reactive for S-100 protein and non-specific cholinesterase, indicating that these cells could be categorized as terminal Schwann cells associated with the periodontal Ruffini endings. Some ordinary Schwann cells also exhibited nestin immunoreaction. From PO 2 to 3 weeks, nestin positive terminal Schwann cells increased in number in accordance with the postnatal development of the periodontal Ruffini endings, while this immuno-expression pattern remained unchanged. Nestin immunoreaction was also recognizable in the satellite cells - but never in the neurons - in the trigeminal ganglion throughout this observation period. This immuno-expression pattern suggests that nestin serves as an intermediate filament for mechanical stability in the periodontal Ruffini endings against external stimuli.

Six-year follow-up in skeletal Class III patient aged over 40 receiving orthognathic surgery and autotransplantation: a case report.

This paper describes the post-operative course of care in a patient requiring orthognathic surgery for skeletal mandibular protrusion in whom autotransplantation of a third molar was performed. A lower third molar that had to be removed for sagittal split ramus osteotomy (SSRO) was transplanted to replace the missing right second molar during pre-surgical orthodontic treatment, contributing to post-treatment occlusal stability. A 44-year-old woman presented with mandibular protrusion. The upper left second molar was congenitally missing and the lower right second molar had been extracted. She was diagnosed as having skeletal mandibular protrusion with excess vertical growth of the mandible and anterior open bite. Correction of the skeletal problem required orthognathic surgery by SSRO and Le Fort I osteotomy without orthodontic tooth extraction. At month 5 during 18 months of pre-surgical orthodontic treatment, the lower left third molar was transplanted to the lower right second molar site. Active treatment was completed after 7 months of post-surgical orthodontic treatment. The patient wore upper and lower Begg-type removable retainers for approximately 2 years. She returned for a recall checkup at 6 years post-treatment. Although radiographic examination revealed root resorption and ankylosis of the autotransplanted tooth at 8 years after transplantation, occlusion has remained stable with no clinically significant complications. The autotransplanted tooth helped stabilize her occlusion and acted as a kind of temporary tooth prior to the final decision on treatment to be given such a dental implant.

Postoperative stability of bimaxillary surgery in Class III patients with mandibular protrusion and mandibular deviation: a frontal cephalometric study.

The aims of this study into bimaxillary surgery were to investigate and compare the postoperative stability of deviated side (lengthened side) and non-deviated side (shortened side), the effect of the type of surgery performed in the mandible, and the changes in signs and symptoms of temporomandibular joint (TMJ) disorders before and after surgery. The sample consisted of 31 Class III patients in whom imbalance between the maxilla and the mandible were corrected by Le Fort I osteotomy combined with bilateral intraoral vertical ramus osteotomy (BIVRO group, n=9), bilateral sagittal split ramus osteotomy (BSSRO group, n=10), or IVRO and SSRO (IVRO+SSRO group, n=12). IVRO+SSRO and BIVRO are more effective in improving TMJ signs and symptoms. There was no significant post-surgical difference between deviated and non-deviated sides in any group. BIVRO and BSSRO showed excellent post-surgical stability on both sides; less was found in the IVRO+SSRO group. The IVRO+SSRO group showed greater transverse displacement in menton point than the BIVRO group. In conclusion, after bimaxillary surgery and in asymmetric patients there were no differences between deviated and non-deviated sides, BIVRO and BSSRO appear to be more stable than IVRO+SSRO.

The 2G allele of promoter region of matrix metalloproteinase-1 as an essential pre-condition for the early onset of oral squamous cell carcinoma.

BACKGROUND: Matrix metalloproteinase (MMP) is known to be involved in the initial and progressive stages of cancer development, and in the aggressive phenotypes of cancer. This study examines the association of single nucleotide polymorphisms in promoter regions of MMP-1 and MMP-3 with susceptibility to oral squamous cell carcinoma (OSCC). METHODS: We compared 170 Japanese OSCC cases and 164 healthy controls for genotypes of MMP-1 and MMP-3. RESULTS: The frequency of the MMP-1 2G allele was higher and that of the 1G homozygote was lower in the OSCC cases (p = 0.034). A multivariate logistic regression analysis revealed that subjects who were 45 years old or older had a significantly increased (2.47-fold) risk of OSCC (95%CI 1.47-4.14, p = 0.0006), and those carrying the MMP-1 2G allele had a 2.30-fold risk (95%CI 1.15-4.58, p = 0.018), indicating independent involvement of these factors in OSCC. One of the key discoveries of this research is the apparent reduction of the MMP-1 1G/1G and 1G/2G genotype distributions among the early onset OSCC cases under the ages of 45 years. It should be noted that the tongue was the primary site in 86.2% of these early onset cases. This could suggest the specific carcinogenic mechanisms, i.e. specific carcinogenic stimulations and/or genetic factors in the tongue. CONCLUSION: Since the 2G allele is a majority of the MMP-1 genotype in the general population, it seems to act as a genetic pre-condition in OSCC development. However this report suggests a crucial impact of the MMP-1 2G allele in the early onset OSCC.

Finite element analysis of a transmandibular implant.

Finite element analysis (FEA) was used to study the influence of bony height and baseplate effect on the transmandibular implant (TMI). FEA was used to assess the stress distribution in the mandible, with and without a baseplate. Forces were applied to the center of a bar space. The von Mises stress (SEQV) was displayed in bone, and shear stress also was measured. Tensile stress was always seen at the so-called saddle area; compressive stress was seen at the inferior border. Tensile strain at the saddle area of a 6-mm height mandible is always 9.1 times greater (corresponding to more SEQV) than that of an 18-mm mandible. At same bone heights, saddle area stresses are similar with or without a baseplate. However, stress at the lateral transossseous post interface with bone was significantly different between different bone height groups. Shear stress around the lateral transossseous post was smaller than does the SEQV of the same site. Decreased bone height dramatically increases stress at the saddle area independent of the baseplate presence. These data suggest that bone apposition is found in the severely atrophic mandibles. Thus, there is no need for a baseplate in a slight to mild atrophic mandible.

Histochemical examinations on cortical bone regeneration induced by thermoplastic bioresorbable plates applied to bone defects of rat calvariae.

We aimed to histologically elucidate whether bioresorbable plates (DeltaSystem) can induce cortical bone formation, which is essential for long-lasting bone augmentation. Standardized bone defects in rat calvariae were covered with a convexly-shaped DeltaSystem plate, and then processed for histological observations. At 1 week, alkaline phosphatase-positive osteoblasts were seen in the newly-formed bone extending from the cavity's bottom, indicating accelerated osteogenesis. A thick layer of soft connective tissue positive for periostin, a hallmark of periosteum, covered this new bone. At 2 weeks, a spongy bone had filled the cavity up to half its height. The inner layer of the soft tissue facing the spongy bone revealed abundant periostin and osteopontin, and had many tartrate-resistant acid phosphatase-positive osteoclasts. At 4 weeks, this layer had given rise to thin new bony matrices without relation to the spongy bone arising from the cavity. These bone matrices had been thickened by 8 weeks, and turned into a thick cortical bone outlining the regenerated bone at 12 weeks. Thus, our study has provided histological evidences of cortical osteogenesis when DeltaSystem plates are used for bone augmentation procedures.

Expression level of vascular endothelial growth factor-C and -A in cultured human oral squamous cell carcinoma correlates respectively with lymphatic metastasis and angiogenesis when transplanted into nude mouse oral cavity.

Angiogenesis is induced by various angiogenic factors including vascular endothelial growth factors (VEGFs), such as VEGF-A, -B, -C and -D, and is involved in tumor progression and metastasis. In an effort to define the expression pattern of VEGFs in oral squamous cell carcinoma (OSCC) and its correlation with clinicopathological factors, we determined the expression levels of VEGFs in OSCC cell lines (HSC-2, HSC-3, HSC-4 and OSC-19) by quantitative RT-PCR and examined their relationship with regional lymph node (LN) and distant metastasis, intratumoral microvessel density (MVD) in tumor transplanted nude mice. We found that HSC-2 and OSC-19 expressed significantly higher levels of VEGF-A and VEGF-C, and caused frequent regional LN metastasis and higher MVD than did the other cell lines. Since VEGF-C is a lymphangiogenic factor, these results suggest that expression of VEGF-C is a useful predictor for LN metastasis.

A clinical case report: interface analysis of a successful well-functioning transmandibular implant from a cadaver mandible.

Transmandibular implants (TMI) are indicated both for functional reconstruction of the severely atrophic mandible and when routine augmentation is unpredictable. This study investigates the interface of bone around a TMI, retrieved from the cadaver. The TMI had successfully functioned for 7 years. The mandible was immersed in 10% formaldehyde and sectioned into nine appropriate pieces. Samples were embedded in polymethylmethacrylate, and cut around the transosseous posts and cortical screws in both vertical and horizontal sections. Samples were analyzed at 400 MHz (nominal lateral resolution, 2.5 microm) using a UH3 Scanning Acoustic Microscope (Olympus, Tokyo, Japan). The middle of implant specimens 1-4 were cut to 50 microm, and stained by toluidine blue for light microscopy. Dental X-rays showed no bone resorption around any implant. On a 2-mm lateral scan, almost uniform interface space was seen between bone and implant surface in cortical screws. There are wider spaces around the transmandibular posts in the superior area. Histology revealed the small area of direct contact. There is bone marrow space in the interface, with no significant fibrous tissue. We interpret these results at the interface to be because of adaptation for stress distribution.

Differential immunohistochemical expression profiles of perlecan-binding growth factors in epithelial dysplasia, carcinoma in situ, and squamous cell carcinoma of the oral mucosa.

The intercellular deposit of perlecan, a basement-membrane type heparan sulfate proteoglycan, is considered to function as a growth factor reservoir and is enhanced in oral epithelial dysplasia and carcinoma in situ (CIS). However, it remains unknown which types of growth factors function in these perlecan-enriched epithelial conditions. The aim of this study was to determine immunohistochemically which growth factors were associated with perlecan in normal oral epithelia and in different epithelial lesions from dysplasia and CIS to squamous cell carcinoma (SCC). Eighty-one surgical tissue specimens of oral SCC containing different precancerous stages, along with ten of normal mucosa, were examined by immunohistochemistry for growth factors. In normal epithelia, perlecan and growth factors were not definitely expressed. In epithelial dysplasia, VEGF, SHH, KGF, Flt-1, and Flk-1were localized in the lower half of rete ridges (in concordance with perlecan, 33-100%), in which Ki-67 positive cells were densely packed. In CIS, perlecan and those growth factors/receptors were more strongly expressed in the cell proliferating zone (63-100%). In SCC, perlecan and KGF disappeared from carcinoma cells but emerged in the stromal space (65-100%), while VEGF, SHH, and VEGF receptors remained positive in SCC cells (0%). Immunofluorescence showed that the four growth factors were shown to be produced by three oral SCC cell lines and that their signals were partially overlapped with perlecan signals. The results indicate that perlecan and its binding growth factors are differentially expressed and function in specific manners before (dysplasia/CIS) and after (SCC) invasion of dysplasia/carcinoma cells.