Consensus guidelines from The American Society of Peritoneal Surface Malignancies on standardizing the delivery of hyperthermic intraperitoneal chemotherapy (HIPEC) in colorectal cancer patients in the United States.

BACKGROUND: The American Society of Peritoneal Surface Malignancies (ASPSM) is a consortium of cancer centers performing cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (HIPEC). This is a position paper from the ASPSM on the standardization of the delivery of HIPEC. METHODS: A survey was conducted of all cancer centers performing HIPEC in the United States. We attempted to obtain consensus by the modified method of Delphi on seven key HIPEC parameters: (1) method, (2) inflow temperature, (3) perfusate volume, (4) drug, (5) dosage, (6) timing of drug delivery, and (7) total perfusion time. Statistical analysis was performed using nonparametric tests. RESULTS: Response rates for ASPSM members (n = 45) and non-ASPSM members (n = 24) were 89 and 33 %, respectively. Of the responders from ASPSM members, 95 % agreed with implementing the proposal. Majority of the surgical oncologists favored the closed method of delivery with a standardized dual dose of mitomycin for a 90-min chemoperfusion for patients undergoing cytoreductive surgery for peritoneal carcinomatosis of colorectal origin. CONCLUSIONS: This recommendation on a standardized delivery of HIPEC in patients with colorectal cancer represents an important first step in enhancing research in this field. Studies directed at maximizing the efficacy of each of the seven key elements will need to follow.

Enterococcus faecalis leakage of root canal sealers: an ex vivo study.

The aim of this ex vivo study was to evaluate bacterial penetration after filling root canals using 3 different techniques. Three experimental groups of 25 teeth each, obturated with lateral-warm-vertical condensation of gutta-percha, Microseal technique and EndoREZ system, respectively, were tested in a split chamber model system using Enterococcus faecalis and monitored for 180 days to determine bacterial penetration. A statistical analysis was performed using the Kaplan-Meier method. Median survival time was 25 days for Microseal system, 41 for lateral-warm-vertical condensation and 81 for EndoREZ®. Significant differences were demonstrated between Microseal and EndoREZ (p less than 0.001) and between Microseal and lateral-warm-vertical condensation technique (p less than 0.05). No statistically significant differences were observed between EndoREZ and lateral-warm-vertical condensation. After 180 days of assessment, 20 percent of the EndoREZ samples resisted bacterial penetration and furthermore, the EndoREZ system has the potential to be a filler system compatible with other currently used systems.

Effect of Cervical Lesions on Fracture Resistance and Failure Mode of Maxillary Central Incisors Restored with Fiber Posts and Complete Crowns.

PURPOSE: To investigate the effect of a cervical cavity extending 1 mm apical to the cemento-enamel junction (CEJ) on fracture resistance and failure mode of maxillary central incisors that have been treated endodontically, present with complete and incomplete ferrules, and are restored with and without a fiber post. METHODS AND MATERIALS: 50 intact human maxillary central incisors were divided into five groups (n=10): CG (control group) 6-mm fer-rule height, no cervical cavity, and without post; (CO) 6-mm ferrule height without post, with a cervical cavity (access to root canal and cervical cavity restored with composite resin), cervical cavity; and post with ferrule heights of 1 mm (CP1), 2 mm (CP2), and 6 mm (CP6) restored with fiberglass post and composite resin core. After complete metal crowns were cemented on all specimens, they were subjected to thermal cycling (6000 cycles, 5°C/55°C), followed by immediate testing of fracture resistance. After failure, the specimens were sectioned buccolingually to evaluate and identify the mode of failure. The data were analyzed with an analysis of variance (ANOVA) and the Student-Newman-Keuls multiple comparison tests (α =0.05). RESULTS: A 1-mm ferrule height (CP1) fracture resistance was significantly lower (531±125 N) compared to the 6-mm ferrule height (CP6) (769±175 N) (p<0.05). With respect to the groups with similar residual dentin, with and without a cervical cavity, CG (667±119 N) and CO (668±119 N), the presence of a post (CP6) increased the resistance to fracture, although no statistically significant difference was demonstrated. Partial decementation was observed in all specimens of CG and CP6, in nine of CP1 and CP2, and in three in CO. Root fractures occurred in 23 specimens. The root surface was exposed 2 mm below the CEJ to simulate bone level. Propagation of subosseous cracks occurred in four specimens in CG and CP2, in seven specimens in CP6, in two specimens in CP1, and in six specimens in CO. All were considered catastrophic failures. CONCLUSIONS: Within the limitations of this study it is suggested that, when restoring an endodontically treated maxillary central incisor that has a cervical lesion and needs to be restored with a complete crown, a fiber post is cemented to improve fracture resistance.

The effect of two composite placement techniques on fracture resistance of MOD restorations with various resin composites.

OBJECTIVE: The aim of this in vitro study was to compare the effect of two restorative placement techniques, centripetal incremental technique (CIT) and bulk-fill technique (BT) on the fracture resistance of Class II MOD restorations with various resin composites in molar teeth. MATERIALS AND METHODS: Fifty-six extracted, caries free third molars were prepared with MOD preparations and restored with resin composites. The specimens were divided into two groups by placement technique, centripetal incremental technique (CIT) and bulk-fill technique (BT). Each group was subdivided into four groups according to resin composite: hybrid (Aelite LS), nano-hybrid (Virtuoso Universal), bulk fill (Filtek One Bulk Fill) and the micro-hybrid (Herculite XRV) as the control. RESULTS: Two-way analysis of variance test (ANOVA) followed by the multiple comparison procedure, Student-Newman-Keuls Method showed no a statistically significant difference between placement techniques and fracture resistance of Class II resin composite restorations (P > 0.05). Herculite XRV resisted a significantly higher load before fracture than the other three materials at a 0.05 level of significance, while Virtuoso Universal scored the lowest load. CONCLUSIONS: There was no significant effect of the two placement techniques on the fracture resistance of Class II resin composite restorations CLINICAL SIGNIFICANCE: Resin composite restorations in Class II MODs using a simplified bulk fill placement technique showed no significant difference in fracture resistance with the centripetal technique in molar teeth.

One year clinical performance and post-operative sensitivity of a bioactive dental luting cement--a prospective clinical study.

A one-year clinical study was performed on the efficacy of a bioactive dental cement (Ceramir C&B) with calcium aluminate and glass ionomer components. The study was performed on 38 crown and bridge abutments in 17 patients. Preparation parameters were recorded, as well as working-times, setting-times, and other handling characteristics. Baseline data were also recorded for gingival inflammation (GI) and pre-cementation sensitivity. Post-cementation parameters included sensitivity, gingival tissue reactions, marginal integrity and discolorations. All patients were seen for recall examinations at 30 days, and 6 months. For sixteen patients one-year recall data were collected on retention and subjective sensitivity. Fifteen subjects were available for one year clinical examinations. Three independent examiners found the working and setting time of the cement to be well within expected limits and that cement removal was easy. Four patients reported low-grades of immediate post-cementation sensitivity, however, this disappeared after an occlusal adjustment or without intervention within one month. At 12 months no retentive failures were recorded and no subjective sensitivity reported. All crowns were rated in the "Excellent" quality category for marginal integrity. Both GI-scores and scores for tooth sensitivity decreased during the course of the study. One year recall data yielded no incidence of secondary caries and no visible marginal discoloration. The new cement was thus found to perform favorably as a luting agent for permanent cementation.

Clinical performance of a bioactive dental luting cement--a prospective clinical pilot study.

OBJECTIVE: To conduct a pilot study determining the clinical efficacy ofa new bioactive dental cement (Ceramir Crown & Bridge) for permanent cementation in fixed prosthodontics. The composition is a hybrid comprised of a calcium aluminate and a glass ionomer. METHODS: This study examined the performance of Ceramir Crown & Bridge after cementation of high-gold alloy and porcelain-fused-to-metal (PFM) single crowns and bridges. A total of 38 crowns and bridge abutments were cemented in 17 patients; 31 were on vital, seven on non-vital teeth. Six were bridges with 14 abutment teeth (12 vital/two non-vital). One fixed splint comprising two abutment teeth was also included in the study. Preparation parameters were recorded, as well as working time, setting time, seating characteristics, and ease of cement removal. Baseline data were collected on dispensing, mixing, and handling of the cement; gingival inflammation index (GI), and a visual analog scale (VAS) and categorical assessment measured pre-cementation sensitivity. Post-cementation parameters were post-cementation sensitivity, categorical and VAS, gingival tissue reaction, marginal integrity, and discoloration. A one-week post-op telephone call recorded subjectively the patients' comfort level. RESULTS: Working time (two minutes) and setting time (four minutes) were well within normal limits. Cement removal was determined to be very easy. Thirteen of 17 patients reported no post-cementation sensitivity after seven days; four reported a low-grade sensitivity. All 17 patients were seen for recall examinations at 30 days and six months. Of the four sensitivity cases, three were related to hyperocclusion, which disappeared spontaneously after adjustment. One case was due to post-cementation pressure from a three-unit bridge, which disappeared without intervention. After six months, no retentive failures were recorded, no sensitivity was subjectively reported, marginal integrity scored 38 alphas, one tooth had a 1 and two teeth a 0.5 GI score. Average VAS score for tooth sensitivity decreased from 7.63 mm at baseline to 0.44 mm at the six-month recall. Average GI score for gingival inflammation decreased from 0.56 at baseline to 0.11 at the six-month recall. CONCLUSION: After six months, Ceramir Crown & Bridge performed favorably as a luting agent for permanent cementation.

Influence of surface remodelling using burs on the macro and micro surface morphology of anatomically formed fibre posts.

AIM: To evaluate the effect of modifying preformed fibre-reinforced composite (FRC) endodontic posts on their surface morphology and to determine how this procedure affects the integrity of the posts. SUMMARY: Surfaces of 10 preformed glass-fibre posts (group 1) and carbon-fibre posts (group 2) were compared with those of individually formed glass-fibre posts (group 3). Ten FRC posts were modelled in order to give them a shape as close as possible to the anatomy of oval root canals. Starting from a preformed cylindrical fibre post 2.5 mm in diameter, it was modelled in such a way as to passively occupy the entire post-space length, using a cast previously created as a guide. Microscopic analyses (optical stereomicroscope and scanning electron microscope) of the post surfaces revealed similar features in all three groups. All posts had regular surfaces after cutting with a diamond bur. Smear layer mainly attributable to the cutting procedures covered the cut surface of some specimens. In conclusion, modulation of a fibre post using a diamond-coated bur did not show a loss of integrity of the post. *Because of the importance of micromechanical retention, the surface integrity of fibre posts may be important for adhesion between post and composite resin. *Modification of a fibre post using a diamond-coated bur did not damage the surface integrity of the posts. *Fibre posts can be ground to a different shape without losing their surface integrity, resulting in posts with a surface that is not visibly different from unmodified commercially available fibre posts.

Conversion of a tumor-binding peptide identified by phage display to a functional chimeric T cell antigen receptor.

Adoptive transfer of ex vivo expanded tumor-specific T cells is a promising therapeutic modality for promoting or augmenting antitumor immunity. Several groups, including ours, are developing antigen receptor gene transfer strategies as a means of generating effector cells for adoptive therapy. Chimeric antigen receptors (CARs) have been described that use single-chain antibodies or cytokine ligands as tumor targeting domains. Here, we describe the capacity of a tumor-binding peptide identified by phage display combinatorial library screening to serve as a CAR targeting domain. A phage library-selected high-affinity 12-mer peptide (Bpep) specific for alpha(v) beta(6) integrin (alpha v beta6) was chosen for these studies. Primary human T cells were genetically modified to express the Bpep-CAR consisting of an alpha v beta6-specific peptide and human IgG4 hinge-Fc extracellular domain fused to the cytoplasmic tail of CD3-zeta. T cell expression of the Bpep-CAR was assessed by Western blot analysis, and trafficking of the Bpep-CAR to the cell surface was demonstrated by flow cytometry. Functionally, Bpep-CAR redirected cytotoxic T lymphocytes specifically kill integrin alpha v beta6+ ovarian tumor targets, and are activated for interferon gamma secretion. Our data suggest that large new repertoires of tumor-specific T cell antigen receptor transgenes might be available through merging combinatorial peptide libraries with CAR construct design.

Chemical and physicochemical studies on the mineral deposits of the human atherosclerotic aorta.

The mineral deposits of the human atherosclerotic aorta were prepared by a new method characterized by the use of mild conditions. Both large and small mineral deposits were isolated from the atherosclerotic plaque and were shown to possess essentially the same chemical composition. The deposits consisted mainly of calcium apatite (71%), carbonate (9%) and contained a relatively high percentage of protein (15%). X-ray diffraction pattern analysis revealed the presence of microcrystals with an average size of approximately 0.1 micron. Electron probe analysis showed that the surface and interior of the mineral deposit had the same chemical composition. However, scanning electron microscopy revealed that the deposits were heterogeneous and consisted of five different structures: (1) individual and conglomerates of smooth-surfaced apheres consisting of spherical layers; (2) spheres consisting of spindle-like, radially arranged particles; (3) fibres forming networks and bundles which sometimes included spherical particles; (4) irregularly shaped particles with fuzzy surfaces and (5) flat plates with smooth surfaces.

Topography of root surfaces treated in vitro with citric acid, elastase and hyaluronidase. A scanning electron microscopy study. Part II.

Sixteen extracted human teeth were separated into two groups, root planed, and treated with either elastase or hyaluronidase following acid demineralization. The duration of enzyme application varied from 5 to 20 minutes. From scanning electron micrographs the following was concluded: (1) The cemental collagen network is composed of previously described extrinsic and intrinsic fiber systems. (2) Root planing, using tactile sense as the final criteria, does not always result in complete elimination of contaminants. (3) Citric acid (pH = 1), applied for 3 to 4 minutes, is an effective means of exposing cemental collagen. (4) Qualitatively, the enzyme treatment subsequent to acid demineralization seemed to result in more effective exposure of the collagen mantle of cementum. (5) Further definitive research must be done to determine, both the usefulness of enzymatic treatment in vitro and in vivo and the optimum enzyme concentrations and duration of application.

Root surface--soft tissue interface. Part I: A review.

A review of the literature is presented with regards to the soft tissue-root surface interface. The basic biological aspects are discussed followed by reports on healing after periodontal surgery. The effect of citric acid, to enhance new attachment, is reviewed in detail. Articles reporting on clinical findings, ultrastructural observation (TEM and SEM), and light microscopic studies have been selected to present the reader with a logical overview of what has been reported in the literature.

Calculus attachment. Review of the literature and new findings.

This study was undertaken in order to provide current information relative to the modes of calculus attachment to tooth surfaces. A total of 63 freshly extracted teeth were fixed, sectioned, and conventionally prepared for light, transmission electron, and scanning electron microscopic examination. Previously reported histologic findings of cuticular attachment, mechanical locking into undercuts, and direct attachment of calculus matrix to the tooth surface were affirmed. The claim of bacterial penetration as a mode of attachment has been rejected. Ultrastructural evidence of cuticular attachment has been presented for the first time via a series of scanning electron micrographs. The most frequently encountered method of attachment was found to be the apparent melding of calculus matrix to the surface of cementum. In many instances, these two substances were virtually indistinguishable.

Simple defluoridation procedures for Kenyan borehole water.

Magnesium oxide and bone meal were used as chemical defluoridating agents to reduce excessive amounts of fluoride from artificial water samples which had been prepared to simulate Kenyan water samples with a fluoride concentration ranging from 1 to 9.3 ppm. The water filtrate from bone meal was clear and palatable. The filtrate from magnesium oxide was slightly slimy and cloudy, but palatable. Either of these chemical agents may be used in simple defluoridation procedures in rural and suburban areas using borehole water to reduce the excess fluoride in the water to beneficial non-toxic levels. Both magnesium oxide and bone meal are inexpensive chemicals and readily available in Kenya.

Combined pure esophageal atresia, duodenal atresia, biliary atresia, and pancreatic ductal atresia: prenatal diagnostic features and review of the literature.

The authors recently managed a case of combined pure esophageal, duodenal, biliary, and pancreatic ductal atresia in a fetus and newborn with Trisomy 21. The authors present a case report and review of the literature, emphasizing the prenatal radiographic features of the combined lesions and the high incidence of associated anomalies including Down's syndrome. Prenatal suspicion of these anomalies warrants karyotype analysis as well as careful pre- and postnatal screening for other anomalies.

Composite resins bonded to porcelain with silane solution.

A system of bonding composite resins to dental porcelain with silane solution produced a reliable bond. The introduction of stresses, particularly thermal and functional, needs to be investigated further and tested clinically. This technique is now being investigated clinically in a number of porcelain-fused-to-gold restorations. It could be an effective method of intraoral repair of fractured or chipped porcelain restorations.

Repairing fractured porcelain: how surface preparation affects shear force resistance.

This article reports on a study of the shear bond strength of porcelain repaired with any of several currently available dentin bonding systems and composite resin. The authors describe the benefits of the use of silane and the decrease in shear bond strength values after thermocycling. The results should be helpful to any practitioner confronted with a restoration that is a candidate for intraoral repair of fractured porcelain.

Enhancing esthetics in porcelain fused to metal through technique modifications.

Three techniques have been discussed and illustrated, with diagrams and examples of clinical cases, that will aid the practitioner to achieve better esthetics when using porcelain fused to metal restorations. The labial butt joint preparation is particularly suitable for upper anterior teeth when the smile line exposes the gingival margin of the restoration and maximal esthetics are demanded. Clinically, the preparation has to be executed in such a way that technically the ceramist does not have to compromise the restoration. Wrong buccal shoulder preparations and too large a space between porcelain and shoulder are the most frequently observed errors. A porcelain sandwich technique in which a thin incisal porcelain layer is condensed between body and translucent porcelain enhances the translucency of the restoration and improves the natural appearance. This technique is particularly suitable for anterior teeth, yet posterior teeth benefit from this method as well, and particularly upper bicuspids are excellent candidates. The third technique uses a blend gold that is applied to the opaque and covered again with another layer of opaque. This method effectively blocks the graying effect often experienced at the gingival margin caused by the underlying metal. A deep chamfer offers the ideal preparation and accommodates the technical requirements best. In conclusion, it can be stated that dentists and dental technicians have available various techniques that make it easier to meet the theoretical and practical requirements of esthetics in dentistry.

Tensile bond strength of fluorosed Kenyan teeth using the acid etch technique.

Tensile bond strength tests were performed on 120 enamel specimens equally distributed over 'normal' American, 'normal' Kenyan and fluorosed Kenyan teeth. The mean tensile bond strength for American teeth was 59.08 +/- 15.81 kg/cm2, for normal Kenyan teeth 41.52 +/- 14.64 kg/cm2 and for fluorosed Kenyan teeth prior to removing the surface layer 49.20 +/- 17.67 kg/cm2. There was an increase in the adhesive bond strength for fluorosed teeth after first grinding and polishing with a green stone followed by pumice (58.84 +/- 20.65 kg/cm2). The coefficients of variation were 27% for fluorosed Kenyan teeth prior to grinding and 35% after grinding. The tested etching times varied from 60 to 150 s. The normal Kenyan teeth had the lowest tensile bond strength. This may have been due to the inability to etch adequately these teeth in 60 s. The increase in tensile bond strength indicates removal of the surface layer of fluorosed enamel by grinding then acid etching may improve the bond strength.

Influence of low-viscosity liners on the retention of three luting materials.

A number of materials are available to protect the pulp from postoperative sensitivity. The effect of a calcium hydroxide liner and a dentinal desensitizing agent (potassium oxalate) on crown retention was investigated. Gold crowns were cemented on standardized crown preparations with zinc phosphate cement, glass-ionomer cement, or one of two resin cements. A tensile force was applied until separation occurred. The mean applied force at rupture varied greatly among the groups, indicating that the pulpal protection agent may have a distinct effect on the retention of cast restorations. In addition, other clinical factors, such as angle of convergence, crown height, and total surface area of the tooth should be considered.

Histologic evaluation of osseointegrated implants restored in nonaxial functional occlusion with preangled abutments.

Of concern with the use of preangled abutments on implants is the transmission of masticatory forces and the angle at which they occur. Nineteen endosseous implants were placed in two subhuman primates. After 6 months, to allow for osseointegration, the implants were fitted with preangled abutments of various degrees and restored with type IV alloy castings. Straight abutments were used as control. Histologic evaluation revealed that, after 1 year of service, the implants exhibited complete osseointegration. Implants, whether restored with straight or preangled abutments, had no adverse effect on the surrounding bone. Soft tissue pockets measured, on average, from 2.2 to 2.6 mm; acute and chronic inflammatory cells were present. When crown loss was observed, it was caused by mechanical failure of components, such as gold screws and the screws used to secure the preangled abutments to the implants. Preangled abutments appear to be a valuable adjunct in implant dentistry, although long-term studies are needed for confirmation.