A randomized clinical trial comparing the efficacy of mandibular implant-supported overdentures and conventional dentures in diabetic patients. Part IV: Comparisons of dietary intake

STATEMENT OF PROBLEM: It is unclear whether the replacement of conventional mandibular dentures with implant-supported overdentures alters the diet and thus improves the nutritional intake of edentulous persons. PURPOSE: The purpose of this study was to compare the pretreatment and posttreatment diets of edentulous diabetic patients who received new dentures with either a conventional complete mandibular denture (CD) or a mandibular implant-supported overdenture (IOD). MATERIAL AND METHODS: New dentures were made for 89 edentulous diabetic patients with acceptable metabolic control without insulin (NIT) or with insulin (IT). A randomized approach was used to assign 37 patients a mandibular CD and 52 patients a mandibular IOD supported by 2 cylindrical implants. Of the 89 patients, 58 submitted a dietary log for 7 consecutive days before treatment (PT) and 6 months after treatment completion (PTC). An average daily intake of 28 essential nutrients was determined for each patient at each time interval. Separate 2 x 2 x 2 repeated analysis of variance (ANOVA) tests were performed for each nutrient to compare the means of the 2 denture groups (CD and IOD), 2 diabetic groups (NIT and IT), and 2 time intervals (PT and PTC). The intakes were also compared with the recommended daily allowance (RDA). RESULTS: ANOVAs for all 28 nutritional variables showed no main effect for either denture type or diabetic treatment. Time effects were seen for magnesium, potassium, copper, and monounsaturated fats. The PTC mean intake of the total sample (N = 58) decreased for all 3 minerals and increased for monounsaturated fats with study dentures. Post hoc tests showed the differences between PT and PTC means to be statistically significant for only magnesium (P=.043) and potassium (P=.015). The percentage of patients with PT intake 25% or more below the RDA ranged from 33% to 85% in the CD group and from 24% to 100% in the IOD group for the same 11 nutrients. PTC fiber intake deficiency was noted in almost all participants. Carbohydrate consumption was markedly lower than that recommended by the American Diabetic Association. CONCLUSION: As is often the case with elderly groups, this group of edentulous diabetic patients showed highly comprised nutritional intakes of fiber, vitamins, and minerals. The replacement of old dentures with new dentures that included either a mandibular CD or IOD did not alter patient diets such that the patients improved their nutritional intakes of essential micronutrients and macronutrients.     

Odontogenic ghost cell carcinoma: a case report with reference to the relation between apoptosis and ghost cells

The neoplastic variant of calcifying odontogenic cyst has various designations, and its malignant counterpart has been reported as aggressive epithelial odontogenic ghost cell tumor or odontogenic ghost cell carcinoma. We present a case of odontogenic ghost cell carcinoma with reference to the relation between the ghost cells and apoptosis. A 33-year-old man complained of a mandibular mass. The mass occupied the entire right side of the mandible with destruction of both buccal and lingual bone. The mass also infiltrated into submandibular and sublingual spaces. Histologically, the mass was composed of a solid proliferation of hyperchromatic and pleomorphic epithelial cells with abnormal mitoses. Islands of ghost cells were frequently admixed with nucleated cells, and there were foci of ameloblastic differentiation. Immunohistochemical stains for cytokeratins, involucrin, and apoptosis-related proteins such as Bcl-2, Bcl-X(L), and Bax were done. Terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labeling (TUNEL) assay was also performed. The nucleated cells adjacent to the ghost cells expressed cytokeratins and involucrin, but the ghost cells had no reaction. Bcl-2 was negative. Both Bcl-X(L) and Bax were demonstrated in the nucleated cells adjacent to the ghost cells. The ghost cells exhibited Bax protein. Some nucleated cells adjacent to the ghost cells were positive with TUNEL assay. The above results indicate that ghost cells undergo abnormal terminal differentiation as an apoptotic process.     

IFN-γ enhances the anti-tumour immune response of dendritic cells against oral squamous cell carcinoma

Objective

To investigate the expression of antigen processing-1 (Tap-1) and Tapasin in oral squamous cell carcinoma (OSCC), and observe the immune response against OSCC by use of IFN-γ-antigen induced dendritic cells (DCs) in vitro and in vivo.

Design

Expression of Tap-1 and Tapasin in different cell lines was analysed. CAL27 cells were treated with IFN-γ. Antigen from the treated cells was presented by DCs. Pulsed DC was then co-cultivated with CD8+ T lymphocyte to induce antigen specific cytotoxic lymphocytes (CTLs). The immune response elicited by CTLs against OSCC was observed.

Results

A significant lower expression of Tap-1 and Tapasin was observed in OSCC cell lines. IFN-γ exerted time-dependent effect for increasing the expression of these genes. Antigen from the treated CAL27 cells was presented by DCs. CTLs were induced and generated a strong immune response in vitro and in vivo.

Conclusions

Tap-1 and Tapasin were downregulated in OSCC. IFN-γ increased the expression of these genes. Use of IFN-γ-antigen induced DCs could induce stronger immune response in vitro and in vivo.     

An ultrastructural analysis of the prototype single-step adhesive applied on enamel and dentin surfaces

A new type of self-etching agent, the single-step adhesive, was developed. The purpose of this study was to investigate the difference in the ultrastructural features of enamel and dentin surfaces following application of the prototype single-step adhesive (EXM618, 3M, MN, USA). Extracted caries-free human premolars were used in this study. Occlusal enamels of teeth--to be used as cut surface specimens--were removed perpendicular to the long axis of the specimens. The mesial and distal surfaces of these teeth, on the other hand, were used as uncut surface specimens in the test. In addition, Mega Bond (Kuraray Medical Inc., Tokyo, Japan) and Xeno CFII Bond (Dentsply Sankin, Tokyo, Japan) were used as controls. After covering half of the tooth surfaces with nail varnish (for control), the other half of each surface was treated with one of the three test adhesives--EXM618, Mega Bond, or Xeno CFII Bond--according to the manufacturer's recommendations. Conditioned enamel and dentin surfaces (i.e., decalcified depth and rugged surface) were observed with a scanning confocal laser microscope (SCLM 1100, Olympus, Tokyo, Japan; henceforth abbreviated as SCLM). Based on the findings of this study, the prototype single-step adhesive EXM618 appears to be suitable for use in dental clinics.     

Platelet-derived growth factor stimulates bone fill and rate of attachment level gain: results of a large multicenter randomized controlled trial

BACKGROUND: Growth factors are generally accepted to be essential mediators of tissue repair via well-established mechanisms of action that include stimulatory effects on angiogenesis and cellular proliferation, ingrowth, differentiation, and matrix biosynthesis. The aim of this study was to evaluate in a large-scale, prospective, blinded, and randomized controlled clinical trial the safety and effectiveness of purified recombinant human platelet-derived growth factor (rhPDGF-BB) mixed with a synthetic beta-tricalcium phosphate (beta-TCP) matrix for the treatment of advanced periodontal osseous defects at 6 months of healing. METHODS: Eleven clinical centers enrolled 180 subjects, each requiring surgical treatment of a 4 mm or greater intrabony periodontal defect and meeting all inclusion and exclusion criteria. Subjects were randomized into one of three treatment groups: 1) beta-TCP + 0.3 mg/ml rhPDGF-BB in buffer; 2) beta-TCP + 1.0 mg/ml rhPDGF-BB in buffer; and 3) beta-TCP + buffer (active control). Safety data were assessed by the frequency and severity of adverse events. Effectiveness measurements included clinical attachment levels (CAL) and gingival recession (GR) measured clinically and linear bone growth (LBG) and percent bone fill (% BF) as assessed radiographically by an independent centralized radiology review center. The area under the curve (AUC), an assessment of the rate of healing, was also calculated for CAL measurements. The surgeons, clinical and radiographic evaluators, patients, and study sponsor were all masked with respect to treatment groups. RESULTS: CAL gain was significantly greater at 3 months for group 1 (rhPDGF 0.3 mg/ml) compared to group 3 (beta-TCP + buffer) (3.8 versus 3.3 mm; P = 0.032), although by 6 months, this finding was not statistically significant (P = 0.11). This early acceleration of CAL gain led to group 1 exhibiting a significantly greater rate of CAL gain between baseline and 6 months than group 3 as assessed by the AUC (68.4- versus 60.1-mm weeks; P = 0.033). rhPDGF (0.3 mg/ml)-treated sites also had significantly greater linear bone gain (2.6 versus 0.9 mm, respectively; P < 0.001) and percent defect fill (57% versus 18%, respectively; P < 0.001) than the sites receiving the bone substitute with buffer at 6 months. There was less GR at 3 months in group 1 compared to group 3 (P = 0.04); at 6 months, GR for group 1 remained unchanged, whereas there was a slight gain in gingival height for group 3 resulting in comparable GR. There were no serious adverse events attributable to any of the treatments. CONCLUSIONS: To our knowledge, this study is the largest prospective, randomized, triple-blinded, and controlled pivotal clinical trial reported to date assessing a putative periodontal regenerative and wound healing therapy. The study demonstrated that the use of rhPDGF-BB was safe and effective in the treatment of periodontal osseous defects. Treatment with rhPDGF-BB stimulated a significant increase in the rate of CAL gain, reduced gingival recession at 3 months post-surgery, and improved bone fill as compared to a beta-TCP bone substitute at 6 months.     

The biologic stability of alumina-zirconia implant abutments after 1 year of clinical service: a digital subtraction radiographic evaluation

The purpose of the present clinical study was to evaluate the biologic stability of alumina-zirconia implant abutments by histologic and radiographic examination. Nineteen partially edentulous patients were treated with 37 external-hexagon implants. After a healing period of 3 to 6 months, alumina-zirconia abutments were connected and restored with cemented single crowns or short-span fixed partial dentures. Periapical radiographs were taken at the time of prosthesis delivery and after 3, 6, and 12 months of follow-up. Crestal alveolar bone level changes were assessed by digital subtraction of consecutive images, and 1-way analysis of variance was used for statistical analysis. No implant, abutment, or restoration failed during the observation period. Bone level changes were statistically insignificant and histologic examination revealed no signs of inflammation. Stable and healthy soft and hard tissue conditions may be expected around alumina-zirconia abutments after 1 year of clinical service. However, long-term data are needed to confirm the present results.     

非血管化游离骨移植中细胞活力的实验研究

目的 :探讨非血管化游离骨块中细胞存活能力及数量与离体时间的关系。方法 :取狗非血管化游离髂骨块 ,在离体 2 5～ 15 0min的不同时间点 ,消化骨块获得细胞 ,进行活细胞计数。对消化获得细胞体外培养2 4h后 ,再进行活细胞计数 ,分析细胞存活与离体时间的关系。结果 :在离体 2 5～ 15 0min时间内 ,骨块细胞的存活率从 91.96%降至 9.5 2 %。统计学检验 ,2 5min组与 70min以前组之间没有统计上的差别 ,P >0 .0 5 ;2 5min组与 70min及其以后组之间有明显差别 ,P <0 .0 1。培养 2 4h后 ,以上各时间点的细胞存活率则从88.73 %到 3 .88% ,组间差别与刚离体时相同 ,但 70min后的各组活细胞率明显下降。结论 :非血管化狗游离髂骨块的离体时间对其中的细胞存活有明显影响 ,离体 70min可能是其关键点 ;在非血管化游离骨移植中 ,尽量缩短骨块的离体时间 ,有利于保存更多的活细胞     

The porphyromonas gingivalis prtP/kgp homologue exists as two open reading frames in strain 381

P- gingivalis is considered to be a major pathogen of adult periodontitis. Among its cadre of putative virulence factors are hemagglutinins (adhesins) and proteases. We here report the cloning, sequencing and characterization of two genes, designated kgp(381) and hagD. Kgp(381), an open reading frame (ORF) of 1095 bp encoding a 40.1 kda protein, has high homology to the proteolytic domain of cysteine protease/hemagglutinin genes. HagD, an ORF of 4077 bp encoding a 147.1 kda protein, contains one HArep sequence which establishes it as an additional member of the HArep multigene family. Although similar in sequence to kgp and prtP which were identified from strains HG66 and W12, respectively, the kgp(381)-hagD genes have several characteristics which distinguish them from kgp and prtP. Foremost among these is a single base difference which produces a termination codon and an immediate frame shift resulting in two ORFs in strain 381 as compared to one ORF in strains HG66 and W12. In addition, a 172 amino acid sequence near the C-terminal end of hagD has very low identity (20.5–27.8%) to the corresponding region of kgp and prtP. These demonstrate that the homologue of kgp and prtP in strain 381 occurs as two separate genes which may genetically separate the adhesive and enzymatic domains of Kgp and PrtP proteins. Reverse polymerase chain reaction (PCR) analysis indicates that hagD expression is regulated by hemin concentration.     

Carnoy液对金黄地鼠颊囊作用的研究

目的了解Carnoy液对粘膜组织损伤的性质，为其用于临床治疗提供理论依据。方法以金黄地鼠颊囊作为模型，以Carnoy液作为涂布试剂，药液作用时间为4min，于术后不同时期处死动物，切取标本，进行光镜和透射电镜观察。结果Carnoy液可引起颊囊粘膜上皮坏死脱落，溃疡形成，穿透深度约0.3mm。术后第3周坏死区上度重新形成，胶原纤维及成纤维细胞明显增多。结论Carnoy液是一种烧灼性质较强的物质，将其用于上皮性囊肿治疗，可因上皮破坏而治愈囊肿或降低其复发率。