Histological comparison of different compressive forces on particulate grafts during alveolar ridge preservation: a prospective proof-of-concept study.

PURPOSE: The aim of this study was to determine the impact of different compressive forces on deproteinized bovine bone mineral (DBBM) particles covered by native bilayer collagen membrane (NBCM) during alveolar ridge preservation (ARP) in the molar area, and to identify any histomorphometric and clinical differences according to the compressive force applied. METHODS: Sockets were filled with DBBM after tooth extraction, and different compressive forces (30 N and 5 N, respectively) were applied to the graft material in the test (30 N) and control (5 N) groups. The DBBM in both groups was covered with NBCM in a double-layered fashion. A crossed horizontal mattress suture (hidden X) was then made. A core biopsy was performed using a trephine bur without flap elevation at the implant placement site for histomorphometric evaluations after 4 months. The change of the marginal bone level was measured using radiography. RESULTS: Twelve patients completed the study. The histomorphometric analysis demonstrated that the mean ratios of the areas of new bone, residual graft material, and soft tissue and the implant stability quotient did not differ significantly between the groups (P>0.05). However, the mean size of the residual graft material showed a significant intergroup difference (P<0.05). CONCLUSIONS: The application of 2 compressive forces (5 N, 30 N) on particulate DBBM grafts during open-healing ARP in the posterior area led to comparable new bone formation, implant feasibility and peri-implant bone level.

Lip Repositioning Surgery Using an Er,Cr:YSGG Laser: A Case Series.

Excessive gingival display (EGD) is a common esthetic concern. Lip repositioning surgery (LRS) was introduced as one of the treatment options to manage EGD. LRS can be used for skeletally and/or muscularly induced EGD. The present case series applied LRS using an Er,Cr:YSGG laser to treat 24 patients with minor vertical maxillary overgrowth or a hypermobile lip. At 6 months, the gingival display had decreased by 3.79 ± 1.59 mm (mean ± standard deviation), and the visible lip body when smiling had increased by 1.23 ± 0.74 mm. A questionnaire revealed that the level of satisfaction with the smile increased among the patients and that they had a positive attitude toward Er,Cr:YSGG laser-assisted LRS.

Nutrient intakes and medication use in elderly individuals with and without dry mouths.

BACKGROUND/OBJECTIVES: The nutrition of the elderly depends on various factors. Oral health, especially oral dryness, can be an important risk factor. In this study, we attempted to determine whether dry mouth is associated with compromised nutrient intakes. SUBJECTS/METHODS: A total of 120 participants aged 65-86 yrs (mean age: 69 ± 1 y) were included in this study. Demographic and health-related characteristics, living status, meals, number of medications, medical conditions, chewing ability, and quality of life, the Oral Health Impact Profile (the OHIP-14) were assessed. We performed one day 24-hr recall assessment for nutrient analyses. The differences of the means between the dry-mouth and non-dry-mouth groups were analyzed. Elderly subjects with xerostomia-induced dry mouth were classified as those who reported at least one dryness symptom on a questionnaire. RESULTS: A significant difference in population distribution was observed among the elderly who took medications for hypertension, diabetes and osteoporosis and was significantly higher in the dry-mouth group (70.2%) than in the non-dry-mouth group (44.4%) (P = 0.005). Compared with the non-dry-mouth group (50.8%), a significantly higher proportion (73.7%) of participants in the dry-mouth group took multiple medicines (≥ 4 medications) (P = 0.019). The intakes of vegetable fat, vitamin E, folate and water in the dry-mouth group were lower than in the non-dry-mouth group. The intakes of fluoride and ω-3 fatty acids were significantly lower in the dry-mouth group than in the non-dry-mouth group. CONCLUSION: The participants in the dry-mouth group exhibited low nutrient and water intakes. It is recommended that the elderly with dry mouth should drink sufficient water and receive targeted and specific nutritional guidance to prevent malnutrition.

Ridge preservation in molar extraction sites with an open-healing approach: A randomized controlled clinical trial.

AIM: To determine the effect of alveolar ridge preservation (ARP) in molar sites without primary flap closure. MATERIALS AND METHODS: Three groups were established: extraction sockets grafted with deproteinized bovine bone mineral containing 10% collagen (DBBM-C) and covered by a native bilayer collagen membrane (NBCM) (test group 1), sockets grafted with DBBM-C only (test group 2), and sockets that healed naturally (control group). Primary flap closure was not attempted. Conebeam computed tomography scans were obtained immediately and then 4 months after ARP. A biopsy was performed. The change of the marginal bone level was measured. RESULTS: There was significantly less horizontal resorption in test group 1 than in the control group at levels 1 mm (-1.02 ± 0.88 [mean ± SD] vs. -4.44 ± 3.71 mm) and 3 mm (-0.31 ± 1.51 vs. -2.27 ± 1.15 mm) below the crest, and significantly less vertical reduction in the midcrestal area in test group 1 than in test group 2 (-0.25 ± 0.95 vs. -1.15 ± 1.63 mm) (p < .05). There were no significant differences between test groups in clinical and histomorphometric measurements. All groups exhibited stable marginal bone levels after 1 year of loading. CONCLUSION: Alveolar ridge preservation without primary flap closure in molar areas was effective in minimizing ridge resorption and facilitated implant treatment.

A comparison of different compressive forces on graft materials during alveolar ridge preservation.

PURPOSE: Following tooth extraction, alveolar ridge preservation (ARP) can maintain the dimensions of ridge height and width. Although previous studies have demonstrated the effects of ARP, few if any studies have investigated the compressive force applied during grafting. The aim of this study was to determine the effects of different compressive forces on the graft materials during ARP. METHODS: After tooth extraction, sockets were filled with deproteinized bovine bone mineral with 10% porcine collagen and covered by a resorbable collagen membrane in a double-layered fashion. The graft materials were compressed using a force of 5 N in the test group (n=12) and a force of 30 N in the control group (n=12). A hidden X suture was performed to secure the graft without primary closure. Cone-beam computed tomography (CBCT) was performed immediately after grafting and 4 months later, just before implant surgery. Tissue samples were retrieved using a trephine bur from the grafted sites during implant surgery for histologic and histomorphometric evaluations. Periotest values (PTVs) were measured to assess the initial stability of the dental implants. RESULTS: Four patients dropped out from the control group and 20 patients finished the study. Both groups healed without any complications. The CBCT measurements showed that the ridge volume was comparably preserved vertically and horizontally in both groups (P>0.05). Histomorphometric analysis demonstrated that the ratio of new bone formation was significantly greater in the test group (P<0.05). The PTVs showed no significant differences between the 2 groups (P>0.05). CONCLUSIONS: The application of a greater compressive force on biomaterials during ARP significantly enhanced new bone formation while preserving the horizontal and vertical dimensions of the alveolar ridge. Further studies are required to identity the optimal compressive force for ARP.

Long-term outcomes of dental implants placed in elderly patients: a retrospective clinical and radiographic analysis.

OBJECTIVES: The aim of this retrospective study was to determine the clinical and the radiographic outcomes of dental implants placed in elderly people older than 65 years. MATERIALS AND METHODS: In total, 902 implants in 346 patients (age: 65-89 years) were followed up for 2-17 years following the implant surgery. The survival rate of these implants was recorded and analyzed. Changes in marginal bone levels were also analyzed in serial radiographs, and Cox regression analysis for implant loss was performed. RESULTS: The survival rates were 95.39% and 99.98% in the implant- and patient-based analyses, respectively (involving a total of 29 implant failures), and the marginal bone loss at the implants was 0.17 ± 0.71 mm (mean ± SD). The number of failures was greatest in patients aged 65-69 years. The Cox regression with shared frailty analysis showed that implant loss was significantly greater in those aged 65-69 years than in those aged 70-74 years (P < 0.05), and it varied between specific implant systems. CONCLUSIONS: Within the limitations of this retrospective study, it was concluded that implant therapy can be successfully provided to elderly patients and that age alone does not seem to affect the implant survival rate.

Zanthoxylum piperitum reversed alveolar bone loss of periodontitis via regulation of bone remodeling-related factors.

ETHNOPHARMACOLOGICAL RELEVANCE: Zanthoxylum piperitum (ZP) has been used to prevent toothache in East Asia. AIM OF STUDY: In this study, we investigated the effects of ZP on periodontitis along with alveolar bone loss. MATERIALS AND METHODS: Twenty-eight male Sprague-Dawley rats were assigned into 4 groups; non-ligated (NOR), ligated and treated vehicle (CTR), ligated and treated 1mg/mL ZP (ZP1), and ligated and treated 100mg/mL ZP (ZP100). Sterilized 3-0 nylon ligature was placed into the subgingival sulcus around the both sides of mandibular first molar. After topical application of 1 and 100mg/mL ZP for 2 weeks, mandibles was removed for histology. In addition, SaOS-2 osteoblast cells were treated 1, 10 and 100µg/mL ZP for 24h to analyze the expressions of alveolar bone-related markers. RESULTS: Several alveolar bone resorption pits, which indicate cementum demineralization were decreased by ZP treatment. Topical ZP treatment inhibited periodontitis-induced alveolar bone loss. In addition, there were significant reduction of osteoclastic activities following topical ZP treatment in periodontium. The expression of RANKL was decreased in SaOS-2 osteoblast cells by treating ZP, while that of OPG was increased. ZP treatment increased the expressions of Runx2 and Osterix in SaOS-2 cells. CONCLUSION: In summary, ZP treatment inhibited alveolar bone loss as well as maintained the integrity of periodontal structures via regulation of bone remodeling. ZP may be a therapeutic target for treating periodontitis.

Preservation of keratinized mucosa around implants using a prefabricated implant-retained stent: a case-control study.

PURPOSE: The aim of this study was to clinically assess the impact of a prefabricated implant-retained stent clipped over healing abutments on the preservation of keratinized mucosa around implants after implant surgery, and to compare it with horizontal external mattress sutures. METHODS: A total of 50 patients were enrolled in this study. In the test group, a prefabricated implant-retained stent was clipped on the healing abutment after implant surgery to replace the keratinized tissue bucco-apically. In the control group, horizontal external mattress sutures were applied instead of using a stent. After the surgical procedure, the width of the buccal keratinized mucosa was measured at the mesial, middle, and distal aspects of the healing abutment. The change in the width of the buccal keratinized mucosa was assessed at 1 and 3 months. RESULTS: Healing was uneventful in both groups. The difference of width between baseline and 1 month was -0.26±0.85 mm in the test group, without any statistical significance (P=0.137). Meanwhile, the corresponding difference in the control group was -0.74±0.73 mm and it showed statistical significance (P<0.001). The difference of width between baseline and 3 months was -0.57±0.97 mm in the test group and -0.86±0.71 mm in the control group. These reductions were statistically significant (P<0.05); however, there was no difference between the 2 groups. CONCLUSIONS: Using a prefabricated implant-retained stent was shown to be effective in the preservation of the keratinized mucosa around implants and it was simple and straightforward in comparison to the horizontal external mattress suture technique.

In vivo bone formation by human alveolar-bone-derived mesenchymal stem cells obtained during implant osteotomy using biphasic calcium phosphate ceramics or Bio-Oss as carriers.

OBJECTIVES: The aim of this study was to evaluate HA coated with different ratios of TCP as a carrier for hABMSCs obtained during implant osteotomy in comparison to slowly-resorbing biomaterial, Bio-Oss, as a negative control, using in vitro and in vivo experiments. MATERIALS AND METHODS: Human ABMSCs (hABMSCs) harvested during implant osteotomy were transplanted using HA/TCP or Bio-Oss as carriers in a murine ectopic transplantation model (n = 12). Pore size and cell affinity were evaluated in vitro. The area of newly formed bone was analyzed histometrically, the number of osteocytes was counted, and immunohistochemical staining was conducted against several markers of osteogenesis, including alkaline phosphatase (ALP), runt-related transcription factor 2 (RUNX-2), osteocalcin (OCN), and osteopontin (OPN). Osteoclast formation was evaluated by tartrate-resistant acid phosphatase staining. RESULTS: The carrier materials had comparable pore sizes. The cell affinity assay resulted in a high proportion of cell adhesion (>90%) in all experimental groups. Substantial new bone and osteocyte formation was observed on both HA/TCP carriers, whereas it was minimal with Bio-Oss. Positive immunostaining for ALP, RUNX-2, OCN, and OPN was observed with HA/TCP, but only limited expression of osteogenic markers with Bio-Oss. Conversely, there was a minimal osteoclast presence with Bio-Oss, but a significant presence of osteoclasts with both HA/TCP carriers. CONCLUSIONS: Both types of scaffolds, BCP and Bio-Oss, showed high stem cell-carrying potential, but the in vivo healing patterns of their complexes with hABMSC could be affected by the microenvironment on the surfaces of the scaffolds.

The hidden X suture: a technical note on a novel suture technique for alveolar ridge preservation.

PURPOSE: The present study investigated the impact of 2 different suture techniques, the conventional crossed mattress suture (X suture) and the novel hidden X suture, for alveolar ridge preservation (ARP) with an open healing approach. METHODS: This study was a prospective randomized controlled clinical trial. Fourteen patients requiring extraction of the maxillary or mandibular posterior teeth were enrolled and allocated into 2 groups. After extraction, demineralized bovine bone matrix mixed with 10% collagen (DBBM-C) was grafted and the socket was covered by porcine collagen membrane in a double-layer fashion. No attempt to obtain primary closure was made. The hidden X suture and conventional X suture techniques were performed in the test and control groups, respectively. Cone-beam computed tomographic (CBCT) images were taken immediately after the graft procedure and before implant surgery 4 months later. Additionally, the change in the mucogingival junction (MGJ) position was measured and was compared after extraction, after suturing, and 4 months after the operation. RESULTS: All sites healed without any complications. Clinical evaluations showed that the MGJ line shifted to the lingual side immediately after the application of the X suture by 1.56±0.90 mm in the control group, while the application of the hidden X suture rather pushed the MGJ line slightly to the buccal side by 0.25±0.66 mm. It was demonstrated that the amount of keratinized tissue (KT) preserved on the buccal side was significantly greater in the hidden X suture group 4 months after the procedure (P<0.05). Radiographic analysis showed that the hidden X suture had a significant effect in preserving horizontal width and minimizing vertical reduction in comparison to X suture (P<0.05). CONCLUSIONS: Our study provided clinical and radiographic verification of the efficacy of the hidden X suture in preserving the width of KT and the dimensions of the alveolar ridge after ARP.

Human bone marrow stem cells cultured under hypoxic conditions present altered characteristics and enhanced in vivo tissue regeneration.

Human bone marrow mesenchymal stem cells (hBMSCs) were isolated from bone marrow of the vertebral body. The hBMSCs were cultured under either hypoxic (1% O2) or normoxic (21% O2; control) conditions and the characteristics as mesenchymal stem cells were compared. Results revealed that hypoxia reduced proliferative potential and colony-forming efficiency of hBMSCs, and significantly enhanced osteogenic and chondrogenic differentiation. The hBMSCs enhanced the regenerative potential of bone in vivo. In vitro synthesis of soluble and insoluble collagen was significantly increased in the hypoxic condition. In vivo collagen tissue regeneration was also enhanced under the hypoxic condition, with concomitant increased expressions of various subtypes of collagen and lysyl-oxidase family mRNA. MicroRNA assays revealed that miR-155-5p, which negatively regulates HIF-1α, was significantly highly expressed. These observations demonstrate that hBMSCs obtained from human vertebrae exhibit altered characteristics under hypoxic conditions, and each factor contributing to hBMSC-mediated tissue healing should be evaluated with the goal of allowing their clinical application.

Effect of FGF-2 on collagen tissue regeneration by human vertebral bone marrow stem cells.

The effects of fibroblast growth factor-2 (FGF-2) on collagen tissue regeneration by human bone marrow stem cells (hBMSCs) were investigated. hBMSCs were isolated from human vertebral body bone marrow during vertebral surgery and a population of hBMSCs with the characteristics of mesenchymal stem cells was observed. The FGF-2 treatment (5 ng/mL) affected on the colony-forming efficiency, proliferation, and in vitro differentiation of hBMSCs. Insoluble/soluble collagen and hydroxyproline synthesis was significantly enhanced in hBMSCs expanded with FGF-2 and the treatment of FGF-2 caused a reduction in the mRNA expression of collagen type I, but an increase of collagen types II and III along with lysyl oxidase family genes. Collagen formation was also examined using an in vivo assay model by transplanting hBMSCs into immunocompromised mice (n=4) and the histologic and immunohistochemical results revealed that significantly more collagen with a well-organized structure was formed by FGF-2-treated hBMSCs at 8 weeks posttransplantation (P<0.05). The DNA microarray assay demonstrated that genes related to extracellular matrix formation were significantly upregulated. To elucidate the underlying mechanism, chemical inhibitors against extracellular-signal-regulated kinase (ERK) and phosphoinositide 3-kinase (PI3K) were treated and following downstream expression was observed. Collectively, FGF-2 facilitated the collagen-producing potency of hBMSCs both in vitro and in vivo, rendering them more suitable for use in collagen regeneration in the clinical field.

Differential effect of water-soluble chitin on collagen synthesis of human bone marrow stem cells and human periodontal ligament stem cells.

Human bone marrow stem cells (hBMSCs) represent a promising regenerative material because of their mutipotency, including their ability to regenerate collagenous soft tissues. We previously found that water-soluble chitin (WSC) enhances the ability of human periodontal ligament stem cells (hPDLSCs) to synthesize collagen tissue. The aim of this study was to determine the effects of WSC on hBMSCs and hPDLSCs for the collagen synthesis both in vitro and in vivo. hBMSCs and hPDLSCs were isolated and expanded with or without 0.3 mg/mL WSC. A series of in vitro and in vivo analyses were performed to evaluate their characteristics as stem cell populations. Then, collagen and hydroxyproline assays were conducted using both in vitro and in vivo assay models, and the real-time polymerase chain reaction was performed to analyze the expression of collagen-related markers. WSC-treated and nontreated hBMSCs and hPDLSCs were transplanted into immunocompromised mice, and histology and immunohistochemistry analyses were conducted after 8 weeks. The in vitro results showed that those cells possessed the characteristics of mesenchymal stem cells. The amount of soluble collagen synthesized was significantly greater in WSC-treated hBMSCs than in the nontreated group; conversely, treatment of hPDLSCs with WSC decreased the formation of soluble collagen. The amount of insoluble collagen synthesized was greater in the WSC-treated groups than in the nontreated groups for both hBMSCs and hPDLSCs. The hydroxyproline contents of the regenerated soluble and insoluble collagens were similar. The expressions of mRNA for collagen types I-V, hyaluronic acid synthase 1 (HAS1), HAS2, and HAS3, and the LOX family were higher in WSC-treated hPDLSCs than in the nontreated group, whereas WSC increased the expression of collagen type III and decreased that of collagen type I in hBMSCs. The histology and immunohistochemistry results revealed that WSC significantly increased the amount of collagen formed in vivo by both types of stem cells. Collectively, treatment with WSC significantly enhanced the collagen-forming potentials of hBMSCs and hPDLSCs, but the collagen they produced exhibited distinctively different characteristics. These findings suggest that the appropriate stem-cell source should be chosen based on the purpose of the required regenerated tissue.

Endoscopic Management of Rectal Dieulafoy's Lesion: A Case Series and Optimal Treatment.

Rectal Dieulafoy's lesion (DL) is rare cause of lower gastrointestinal bleeding. Because of its rarity, there is no consensus on the optimal endoscopic hemostasis technique for rectal DL. We analyzed six patients who underwent endoscopic management for rectal DL after presenting with hematochezia at a single institute over 10 years. Of the six patients, three underwent endoscopic band ligation (EBL) and three underwent endoscopic hemoclip placement (EHP). Only one patient was treated with thermocoagulation. There were no immediate complications in any of the patients. None of the patients required a procedure or surgery for the treatment of rebleeding. Mean procedure times of EBL and EHP were 5.25 minutes and 7 minutes, respectively. Both EHP and EBL are shown to be effective in the treatment of bleeding rectal DL. We suggest that EBL may have potential as the preferred therapy owing to its superiority in technical and economic aspects, especially in elderly and high-risk patients.

Improvement in periodontal healing after periodontal surgery supported by nutritional supplement drinks.

PURPOSE: The aim of this study was to determine the effects of nutritional supplements on periodontal health and tooth mobility after surgery. METHODS: Patients were randomly assigned to an intervention group who consumed nutritional supplement drinks for 8 weeks, while the placebo group did not receive any such supplements. The gingival index (GI) and tooth mobility were measured at baseline and at 1, 4, and 8 weeks. In addition, the oral health impact profile-14 and anthropometric measurements along with loss of appetite and dietary intake were assessed at baseline and 8 weeks. RESULTS: At 1 week, GI values were reduced in the intervention group (P<0.05), and tooth mobility had increased, but to a lesser extent in the intervention group (P<0.05). At 8 weeks, the intakes of protein, vitamins A and B1, and niacin were increased in the intervention group. CONCLUSIONS: These results demonstrate that nutritional supplementation improves early periodontal healing after surgery.

Alveolar bone resorption induced by CD4+CD45RB high-density T-cell transfer in immunocompromised mice.

BACKGROUND: The aims of this study are to determine whether the antigen-inexperienced (naive, CD45RB high-density) T-cell (CD4(+)CD45RB(High) T-cell) transfer model is associated with alveolar bone resorption, to elucidate the local osteogenic/adipogenic potential of alveolar bone marrow stromal cells (ABCs) from T-cell-transferred animals, and to investigate the systemic osteogenic potential by transplanting human periodontal ligament stem cells (hPDLSCs) into these animals. METHODS: CD4(+)CD45RB(High) and CD4(+)CD45RB(Low) (antigen-experienced [memory, CD45RB low-density]) T cells were sorted and transferred into severe combined immunodeficiency (SCID) mice to induce inflammatory bowel disease-like syndrome (n = 8). hPDLSCs were transplanted into T-cell-transferred SCID mice to examine ectopic cementum formation 8 weeks after T-cell transfer. The mandibles and tibias of these mice were retrieved for microcomputed tomography (micro-CT), histomorphometric analysis, and isolation of ABCs 16 weeks after T-cell transfer. The in vitro osteogenic and adipogenic potentials of the ABCs were evaluated. RESULTS: Histologic and micro-CT analysis revealed that the transfer of CD4(+)CD45RB(High) T-cell subset was sufficient for alveolar bone resorption and affected the osteogenic/adipogenic potential of ABCs. Furthermore, it was found that CD4(+)CD45RB(High) T-cell-transferred animals have decreased systemic osteogenic potential, as evidenced using the in vivo ectopic hPDLSC transplantation model. CONCLUSION: CD4(+)CD45RB(High) T-cell transfer induced both alveolar bone resorption and reduced systemic osteogenic potential, with a concomitant downregulation of the osteogenic potential of ABCs.

Ridge preservation using demineralized bone matrix gel with recombinant human bone morphogenetic protein-2 after tooth extraction: a randomized controlled clinical trial.

PURPOSE: The aim of the present randomized controlled trial was to determine the safety and efficacy of injectable demineralized bone matrix (DBM) gel combined with recombinant human bone morphogenetic protein-2 (rhBMP-2) on alveolar ridge preservation after tooth extraction. MATERIALS AND METHODS: A total of 69 patients were randomly assigned to either a test group (n = 35) or a control group (n = 34). In the test group, DBM, together with rhBMP-2 (0.05 mg/mL; rhBMP-2/DBM) was transplanted into the extraction sockets. The control group received DBM alone. The safety of rhBMP-2/DBM was evaluated by oral examination, serum chemistry, and hematologic examination. The radiographic changes in alveolar bone height and width were measured using computed tomography scans performed immediately after transplant and again 3 months thereafter. RESULTS: Healing was uneventful in all subjects, with no anticipated adverse events and no clinically significant changes in the serum chemistry and hematologic findings. No meaningful immune response was found among the study groups. No significant difference was found in the radiographic changes of alveolar bone height and width (P > .05). CONCLUSIONS: This new injectable biomaterial can be used easily and safely in clinical applications.

Endoscopic submucosal dissection for early gastric cancer with undifferentiated histology: could we extend the criteria beyond?

BACKGROUND: Endoscopic submucosal desection (ESD) is an effective treatment for selected patients with early gastric cancer (EGC). The purpose of this study was to examine the short-term and long-term outcomes of ESD of undifferentiated early gastric cancer. METHODS: Data for 1,241 patients who underwent ESD for treatment of EGC between February 2003 and May 2010 were collected. We performed a retrospective analysis of the medical records of 74 patients diagnosed with undifferentiated EGC. We divided the enrolled cases into two groups: the expanded-criteria group (EC group) versus the non-EC group, according to lesion size, presence of ulceration, and pathologic review. RESULTS: Of a total of 74 lesions with undifferentiated EGC, as a result of pathologic examination the EC group included 29 cases and the non-EC group included 45 cases. The mean diameter of lesions was 19.86 ± 12.5 mm. The overall rates of en bloc resection and complete resection were 90.5% (67/74) and 73% (54/74), respectively. The curative resection rate was low at 31.1%. If limited to the pathologically diagnosed EC group, the curative resection rate was 79.3% (23/29). During median follow-up periods of 34 months (range 7-81), local recurrences were observed in 5.5% (4/74) of patients. All of these were in the non-EC group and all underwent noncurative resection. There was no mortality related to ESD for treatment of EGC during follow-up. CONCLUSIONS: ESD may be a feasible treatment for selected patients with undifferentiated EGC; this should be validated by development of new criteria for ESD for treatment of EGC.

Predictive factors for lymph node metastasis in signet ring cell gastric cancer and the feasibility of endoscopic submucosal dissection.

PURPOSE: Endoscopic submucosal dissection has recently been practiced on a differentiated type of early gastric cancer. However, there is no clear evidence for endoscopic treatments of signet ring cell carcinoma. The aim of this study is to identify the predictive clinicopathological factors for lymph node metastasis in signet ring cell carcinoma for assisting endoscopic submucosal dissection trials. MATERIALS AND METHODS: A total of 186 patients with early signet ring cell carcinoma who underwent radical curative gastrectomy between January 2001 and September 2009 were enrolled in this study. Retrospective reviews of their medical records are being conducted. Several clinicopathologic factors were being investigated in order to identify predictive factors for lymph nodes metastasis: age, gender, tumor size, type of operation, tumor location, gross type, ulceration, Lauren's classification, depth of invasion, and lymphatic invasion. RESULTS: The lymph node metastasis rate for signet ring cell carcinoma was 4.3% (n=8). Of the 186 lesions with early signet ring cell carcinoma, 91 (48.9%) tumors were larger than 15 mm in size and 40 (21.5%) showed submucosal invasions in the resection specimens. In multivariate analysis, only the lymphatic invasion (P<0.0001) showed an association with lymph node metastasis. To evaluate cutoff values for tumor sizes in the presence of lymph node metastasis, early signet ring cell carcinomas with lymphatic invasions were excluded. In the absence of lymphatic invasion, mucosal cancer with tumor sizes <15 mm had no lymph node metastasis. CONCLUSIONS: Endoscopic submucosal dissection can be performed on patients with early signet ring cell carcinoma limited to the mucosa and less than 15 mm.

The clinical effect of locally delivered minocycline in association with flap surgery for the treatment of chronic severe periodontitis: a split-mouth design.

OBJECTIVE: The purpose of this study was to determine the effectiveness of adjunctive application of locally delivered minocycline ointment associated with flap surgery for the treatment of patients with chronic severe periodontitis. MATERIAL AND METHODS: Twenty patients with chronic severe periodontitis were treated in a split-mouth study to either adjunctive application of locally delivered minocycline ointment in association with flap surgery (FM) or flap surgery only (FO); additional minocycline application was performed at 3 months post operation. Clinical evaluation of the plaque index, probing depth (PD), bleeding on probing (BOP), gingival recession, and clinical attachment level (CAL) was conducted at baseline and at 3 and 6 months after treatment. RESULTS: Clinical evaluations revealed that although both sites exhibited clinical improvement, there was a statistically significant reduction in PD (3.34 ± 0.03 mm) and BOP (78.01 ± 11.42%), and a significant gain of CAL (1.88 ± 0.21 mm) at the FM site compared with the FO site (reduction of PD and BOP: 2.62 ± 0.06 mm, 50.33 ± 15.01%, and gain of CAL: 1.55 ± 0.13 mm) at 6 months post operation (p < 0.05). CONCLUSION: Adjunctive application of locally delivered minocycline may be beneficial to the surgical treatment protocol of chronic severe periodontitis.