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PubMed1989

Comparison of short and long thumb-spica casts for non-displaced fractures of the carpal scaphoid.

A prospective study was undertaken of fifty-one patients who were randomly assigned to treatment with either a long or a short thumb-spica cast for a non-displaced fracture of the carpal scaphoid. The duration of follow-up was at least until union; the average follow-up was twelve months. Twenty-eight fractures were treated with a long thumb-spica cast and twenty-three, with a short thumb-spica cast. The hands that initially were treated with a long thumb-spica cast were placed in a short thumb-spica cast after six weeks. Fractures that initially were treated with a long thumb-spica cast united at an average of 9.5 weeks and those that were maintained in a short thumb-spica cast, at an average of 12.7 weeks. There were no non-unions and two delayed unions in the fractures that initially were treated with a long thumb-spica cast, compared with two non-unions and six delayed unions in those that had only a short thumb-spica cast. Fractures of the proximal or middle third of the carpal scaphoid had a significantly shorter time to union when they were treated initially in a long thumb-spica cast. Fractures of the distal third did well regardless of the type of immobilization.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

PubMed1981

[Cast fractures of dental Ni-Cr alloys (author's transl)].

Cast fractures of Ni-Cr alloys were investigated by means of scanning electron microscopy, energy dispersive X-ray spectrometry, electron-probe microanalysis, density measurements, setting and thermal expansion measurements and compressive tests. Three-Ni-Cr alloys for crowns and bridges were cast in spiral configurations by an argon-arc pressured type or an induction argon-pressured type-casting machine. The amount of cast fracture increase with an increase in cast temperature, but not with an increase of holding time at cast temperature. Ni-Cr alloys have more cast fractures in a phosphate-bonded investment than in a gypsum-bonded cristobalite investment. Fracture surfaces have an exposed dendrite structure, indicating the presence of cast porosity. The trigger of cast crack can be a cast porosity and the propagation of crack to fracture may be mainly due to the strength of investments.

Chromium Alloys↗

PubMed1996

In vitro evaluation of four methods of attaching transfixation pins into a fiberglass cast for use in horses.

OBJECTIVE: To compare the axial stability provided by 4 methods of attaching transfixation pins into a fiberglass cast. DESIGN: Axial stability of 4 methods of transfixation pin attachment to a fiberglass cast cylinder was determined in vitro. Methods of attachment included simple incorporation of the pins into the cast, placement of a washer and nut on the pin and incorporation into the cast, extension of pins beyond the cast and attachment to a steel halo, and washers within the cast and attachment to a steel halo. POPULATION: A model was designed to simulate a transfixation cast applied to the equine metacarpus. 8 identical constructs were present in each of the 4 groups. 6 fiberglass cylinders were also tested to identify the contribution of the cast cylinder to the overall stability of the transfixation cast. PROCEDURE: Load-sufficient curves were recorded, and a stiffness modulus was calculated for each treatment group and for a simple fiberglass cylinder without transfixation pins. RESULT AND CONCLUSION: There was no significant difference among the 4 methods of attachment. The fiberglass cast material appears to be the major determinant of axial stability.

Animals↗

PubMedDate not supplied

Cast changes: synthetic versus plaster.

A review of the changes in casting since the introduction of improved synthetic casting materials in the 1970s is presented. There is very little in the literature on nursing implications regarding the newer casting materials. Improvements in synthetic materials used in the casting of children include a fiberglass-free, latex-free casting polymer, with child-friendly prints now available. Though the use of synthetic casting predominates the market, plaster of Paris is still the mainstay for serial casting and casting requiring superior moldability and conformability. The advantages and disadvantages of synthetic and plaster of Paris casting, as well as nursing care of the child in each type of cast are summarized.

Calcium Sulfate↗

PubMed2004

Neutron radiography inspection of investment castings.

Investment casting, also known as the lost wax process, is a manufacturing method employed to produce near net shape metal articles. Traditionally, investment casting has been used to produce structural titanium castings for aero-engine applications with wall thickness less than 1 in (2.54 cm). Recently, airframe manufacturers have been exploring the use of titanium investment casting to replace components traditionally produced from forgings. Use of titanium investment castings for these applications reduces weight, cost, lead time, and part count. Recently, the investment casting process has been selected to produce fracture critical structural titanium airframe components. These airframe components have pushed the traditional inspection techniques to their physical limits due to cross sections on the order of 3 in (7.6 cm). To overcome these inspection limitations, a process incorporating neutron radiography (n-ray) has been developed. In this process, the facecoat of the investment casting mold material contains a cocalcined mixture of yttrium oxide and gadolinium oxide. The presence of the gadolinium oxide, allows for neutron radiographic imaging (and eventual removal and repair) of mold facecoat inclusions that remain within these thick cross sectional castings. Probability of detection (POD) studies have shown a 3 x improvement of detecting a 0.050 x 0.007 in2 (1.270 x 0.178 mm2) inclusion of this cocalcined material using n-ray techniques when compared to the POD using traditional X-ray techniques. Further, it has been shown that this n-ray compatible mold facecoat material produces titanium castings of equal metallurgical quality when compared to the traditional materials. Since investment castings can be very large and heavy, the neutron radiography facilities at the University of California, Davis McClellan Nuclear Radiation Center (UCD/MNRC) were used to develop the inspection techniques. The UCD/MNRC has very unique facilities that can handle large parts up to 39 ft (12 m) in length and 13 ft (4 m) high weighing up to 5000 lbs (2300 kg). These handling systems are robotically driven. The neutron radiographic system consists of a highly thermalized neutron beam. The neutron beam has an intensity of 5.6 x 10(6) n/cm2 s, with a L/D = 200 at a power of 2 MW. A divergent beam collimator is used which provides a beam of approximately 22 in (56 cm) in diameter at the film plane. A vacuum cassette with a gadolinium vapor deposited screen is used to collect the image. Exposure times can be as short as 3 min, or up to 30 min.

Journal Article↗

PubMed2004

Evaluation of disinfected casts poured in gypsum with gum arabic and calcium hydroxide additives.

STATEMENT OF PROBLEM: Disinfection of stone casts is an important measure for the control of cross-contamination. Many approaches have been used to disinfect stone casts, but information regarding the accuracy of the resultant casts is limited. PURPOSE: The purpose of this in vitro study was to evaluate the dimensional accuracy, incidence of abutment fracture, and the abutment reproduction of disinfected stone casts made from elastomeric impressions and to determine the effect of gum arabic and calcium hydroxide additives on these properties. MATERIAL AND METHODS: Two aqueous solutions of chemical disinfectants (0.525% sodium hypochlorite and 0.1% povidone iodine) were used as mixing water substitutes for 3 types of dental stone: Types III (Lab Stone), IV (Mile Stone), and V (Die Keen). These stone powders were subjected to further modification by adding 1% gum arabic and 0.132% calcium hydroxide before mixing at the manufacturer-recommended liquid/powder ratios (0.30 for Type III, 0.21 for Types IV and V, respectively). As these additives increased the fluidity of the mix, reduced liquid/powder ratios (0.26 for Type III, 0.19 for Types IV and V, respectively) were also evaluated. Unmodified stone powder mixed with water served as the control. These modifications resulted in 7 test groups for each type of stone. Mixed stones of these groups were poured into 10 putty/wash vinyl polysiloxane impressions made of a customized definitive cast. The percentage of abutments fractured at the time of releasing the resultant casts, as well as the percentages of incompletely reproduced abutments, abutments with air bubbles, and abutments with defective finish lines were compared statistically among the tested groups using the chi-square test (alpha=.05). The average dimensional deviations of the resultant cast from the definitive cast measured in mm were statistically analyzed using 1-way ANOVA (alpha=.05) followed by the Dunnett test to detect any differences among the tested groups. RESULTS: No significant difference was found in abutment fracture or abutment defects for the different formulations of each type of stone used. The resultant casts showed no significant dimensional changes except for Type III and IV stones modified by gum arabic and calcium hydroxide additives and mixed at the recommended liquid/powder ratios. CONCLUSION: Both 0.525% sodium hypochlorite and 0.1% povidone iodine can be used to disinfect dental gypsum with no significant effect on the dimensional accuracy and reproducibility of the resultant casts. Addition of gum arabic and calcium hydroxide to the hemihydrate powders before mixing does not aid in reducing the incidence of defective abutment reproduction.

Analysis of Variance↗

PubMed2004

The quality of dental casts used in crown and bridgework.

OBJECTIVE: To assess the quality of dental casts used in crown and bridge construction. DESIGN: Observational cross-sectional study of dental casts. SETTING: Commercial dental laboratories and a university dental hospital laboratory in the UK. MATERIALS AND METHODS: A sample (n = 150) of working and opposing casts used for crown and bridgework prescribed by general dental practices and a dental hospital were sampled from two commercial dental laboratories and an 'on-site' university dental hospital laboratory respectively. A simple '3 point' assessment scale of quality (good, fair and poor) was used to categorise the casts depending on the clarity of reproduction of soft and hard tissues. RESULTS: The quality of opposing casts used for articulation purposes was significantly better (P<0.001) than that of the working casts. In addition it was found that for working casts the quality in the preparation area(s) was significantly better (p<0.001) than that in areas remote from preparation(s) in the same arch. In general, the quality of casts in the incisal or occlusal surfaces was better than the buccal and lingual surfaces. CONCLUSIONS: This study has demonstrated that variation exists in the quality of casts used in crown and bridgework, specifically those used in the construction of indirect restorations and also those used for articulation purposes. This study highlights the need for clinicians to exercise continued vigilance with crown and bridge impressions, and casts, particularly in areas away from the prepared teeth.

Analysis of Variance↗

PubMedDate not supplied

Adaptive significance of the Indian caste system: an ecological perspective.

Indian society is an agglomeration of several thousand endogamous groups or castes each with a restricted geographical range and a hereditarily determined mode of subsistence. These reproductively isolated castes may be compared to biological species, and the society thought of as a biological community with each caste having its specific ecological niche. In this paper we examine the ecological-niche relationships of castes which are directly dependent on natural resources. Evidence is presented to show that castes living together in the same region had so organized their pattern of resource use as to avoid excessive intercaste competition for limiting resources. Furthermore, territorial division of the total range of the caste regulated intra-caste competition. Hence, a particular plant or animal resource in a given locality was used almost exclusively by a given lineage within a caste generation after generation. This favoured the cultural evolution of traditions ensuring sustainable use of natural resources. This must have contributed significantly to the stability of Indian caste society over several thousand years. The collapse of the base of natural resources and increasing monetarization of the economy has, however, destroyed the earlier complementarity between the different castes and led to increasing conflicts between them in recent years.

Adaptation, Biological↗

PubMed2002

Molecular and culture-based analyses of prokaryotic communities from an agricultural soil and the burrows and casts of the earthworm Lumbricus rubellus.

The microbial populations in no-till agricultural soil and casts of the earthworm Lumbricus rubellus were examined by culturing and molecular methods. Clone libraries of the 16S rRNA genes were prepared from DNA isolated directly from the soil and earthworm casts. Although no single phylum dominated the soil library of 95 clones, the largest numbers of clones were from Acidobacteria (14%), Cytophagales (13%), Chloroflexi (8%), and gamma-Proteobacteria (8%). While the cast clone library of 102 clones was similar to the soil library, the abundances of several taxa were different. Representatives of the Pseudomonas genus as well as the Actinobacteria and Firmicutes increased in number, and one group of unclassified organisms found in the soil library was absent in the cast library. Likewise, soil and cast archaeal 16S rRNA gene libraries were similar, although the abundances of some groups were different. Two hundred and thirty aerobic bacteria were also isolated on general heterotrophic media from casts, burrows, and soil. The cast isolates were both phenotypically and genotypically different from the soil isolates. The cast isolates were more likely to reduce nitrate, grow on acetate and Casamino Acids, and utilize fewer sugars than the soil isolates. On the basis of their ribotypes, the cast isolates were dominated by Aeromonas spp. (28%), which were not found in the soil isolates, and other gamma-Proteobacteria (49%). In contrast, the soil isolates were mostly Actinobacteria (53%), Firmicutes (16%), and gamma-Proteobacteria (19%). Isolates obtained from the sides of earthworm burrows were not different from the soil isolates. Diversity indices for the collections of isolates as well as rRNA gene libraries indicated that the species richness and evenness were decreased in the casts from their levels in the soil. These results were consistent with a model where a large portion of the microbial population in soil passes through the gastrointestinal tract of the earthworm unchanged while representatives of some phyla increase in abundance.

Agriculture↗

PubMed2006

Women's health in a rural community in Kerala, India: do caste and socioeconomic position matter?

OBJECTIVES: To examine the social patterning of women's self-reported health status in India and the validity of the two hypotheses: (1) low caste and lower socioeconomic position is associated with worse reported health status, and (2) associations between socioeconomic position and reported health status vary across castes. DESIGN: Cross-sectional household survey, age-adjusted percentages and odds ratios, and multilevel multinomial logistic regression models were used for analysis. SETTING: A panchayat (territorial decentralised unit) in Kerala, India, in 2003. PARTICIPANTS: 4196 non-elderly women. OUTCOME MEASURES: Self-perceived health status and reported limitations in activities in daily living. RESULTS: Women from lower castes (scheduled castes/scheduled tribes (SC/ST) and other backward castes (OBC) reported a higher prevalence of poor health than women from forward castes. Socioeconomic inequalities were observed in health regardless of the indicators, education, women's employment status or household landholdings. The multilevel multinomial models indicate that the associations between socioeconomic indicators and health vary across caste. Among SC/ST and OBC women, the influence of socioeconomic variables led to a "magnifying" effect, whereas among forward caste women, a "buffering" effect was found. Among lower caste women, the associations between socioeconomic factors and self-assessed health are graded; the associations are strongest when comparing the lowest and highest ratings of health. CONCLUSIONS: Even in a relatively egalitarian state in India, there are caste and socioeconomic inequalities in women's health. Implementing interventions that concomitantly deal with caste and socioeconomic disparities will likely produce more equitable results than targeting either type of inequality in isolation.

Adult↗

PubMed2000

Effectiveness and safety of a nonremovable fiberglass off-bearing cast versus a therapeutic shoe in the treatment of neuropathic foot ulcers: a randomized study.

OBJECTIVE: To evaluate and compare the rate of reduction of the surface area of neuropathic plantar ulcers in diabetic patients treated with nonremovable rigidity-differentiated fiberglass off-bearing casts or a cloth shoe with a rigid sole with unloading alkaform insoles. The secondary aim was to evaluate the side effects and degree of patient acceptance of treatment. RESEARCH DESIGN AND METHODS: Fifty diabetic patients with neuropathic plantar ulcers were consecutively enrolled and randomized to one of two treatment groups. Of the 50 patients, 24 were treated with a specialized cloth shoe with a rigid sole and an unloading alkaform insole (shoe group), and 26 patients were treated with a nonremovable off-bearing fiberglass cast (cast group). All patients in both study groups returned to the clinic for weekly control visits. Their ulcers were treated with a standard dressing. Tracings of the ulcer area using a transparent dressing were performed on the day of entry to the study and after 30 days of treatment. The presence of new ulcerations caused by the use of the pressure-relief apparatus was recorded. Patient acceptance of the treatment was measured using a visual analog scale. RESULTS: At the end of the treatment period, an 8.3% increase of the ulcer area was observed in two patients in the shoe group, whereas in the cast group, no patient presented an increase. The reduction of the ulcer area was statistically more rapid in the cast group (Mann-Whitney test, P = 0.0004). Furthermore, the number of ulcers completely healed at the 30-day time point was 13 (50%) in the cast group and 5 (20.8%) in the shoe group (P = 0.03). In both groups, no side effects were recorded. The average score +/- SD of patient acceptance was 91.15 +/- 9.9 in the shoe group and 88.33 +/- 17.3 (NS) in the cast group. CONCLUSIONS: Our study has shown a significant difference in the speed of the reduction of neuropathic plantar ulcers treated with a fiberglass cast compared with a specialized cloth shoe. The use of fiberglass material with variable rigidity has also shown two important results: the elimination of side effects including ulcers caused by the cast, and high patient acceptance. These data show that the use of off-bearing casts made with fiberglass bandages of variable rigidity is the elective treatment of neuropathic plantar ulcers.

Aged↗

PubMed2001

Application of laser measuring, numerical simulation and rapid prototyping to titanium dental castings.

OBJECTIVES: This paper describes a method of making titanium dental crowns by means of integrating laser measuring, numerical simulation and rapid prototype (RP) manufacture of wax patterns for the investment casting process. METHODS: Four real tooth crowns (FDI No. 24, 25, 26, 27) were measured by means of 3D laser scanning. The laser digitized geometry of the crowns was processed and converted into standard CAD models in STL format, which is used by RP systems and numerical simulation software. Commercial software (MAGMASOFT) was used to simulate the casting process and optimize the runner and gating system (sprue) design. RP crowns were 'printed' directly on a ModelMaker II 3D Plotting System. A silicone negative mold (soft tool) was made from the RP crowns, then more than hundreds wax crowns were duplicated. The duplicated crowns were joined to the optimized runner and gating system. By using the investment casting process 20-25 replicas of each crown were made on a centrifugal casting machine. All castings were examined for porosity by X-ray radiographs. RESULTS: By using the integrated scanning, simulation, RP pattern and casting procedure, cast crowns, free of porosity, with excellent functional contour and a smooth surface finish, were obtained from the first casting trial. SIGNIFICANCE: The coupling of laser digitizing and RP indicates a potential to replace the traditional 'impression taking and waxing' procedure in dental laboratory, with the quality of the cast titanium prostheses also being improved by using the numerically optimized runner and gating system design.

Calcium Sulfate↗

PubMed1993

Castability and surface hardness of titanium cast plates obtained from experimental phosphate-bonded silica investment molds.

The effect of 12 different experimental compositions of phosphate-bonded SiO2 investments was examined on cast pure titanium. The mold temperature was 600 degrees C and the casting was conducted with an argon-arc melting and pressure casting machine. Castability was evaluated by the volume of casting porosity, which was calculated from the volume of wax pattern (15 mm x 15 mm x 1.5 mm), the weight of cast plate and the specific density of pure titanium. The existence of inner casting porosities was confirmed by an X-ray non-destructive inspection instrument. Cast plates made in molds with cristobalite had significantly lower castability and higher surface hardness than those in molds with quartz as a refractory material. Cast plates in molds (quartz-cristobalite mixtures) with 20% binder had lower surface hardness and fewer casting porosities than those in molds with 10% binder.

Analysis of Variance↗

PubMedDate not supplied

New die design for dimensional accuracy assessment of crown castings.

PURPOSE: The aim of this study was to introduce a newly designed die for ceramometal restoration, and to compare the dimensional accuracy with the traditional complete-crown design. Two methods of dimensional accuracy assessment, vertical axial discrepancy and transverse diametral percentage, were compared. MATERIALS AND METHODS: Patterns were prepared from two different die designs--complete crown and ceramometal. Two investments available for titanium crown casting were used, Titavest CB and T-invest C & B. Titanium castings were made from each investment with a high-pressure casting machine. Vertical axial discrepancy of casting was determined by measuring the discrepancy for each set of wax patterns and their castings on the same die under a traveling microscope. Dimensional accuracy was expressed as vertical axial discrepancy and by transforming the vertical axial discrepancy into transverse diametral percentage. RESULTS: Both dies produced undersized castings with T-invest C & B and oversized castings with Titavest CB. Dimensional accuracy assessment of the two different types of crown casting design showed no significant difference in vertical axial discrepancy. CONCLUSION: Compared to the traditional transverse diametral percentage calculation, the vertical axial discrepancy assessment is independent of the die's dimensions. The two types of investment materials studied resulted in castings with different dimensional accuracies.

Crowns↗

PubMed1992

Muscle atrophy continues after early cast removal following tendon repair.

We studied soleus (SOL), plantaris (PLN), and gastrocnemius (GST) muscles to determine whether early cast removal minimizes muscle atrophy or permits recovery from atrophy after tendon repair. After right tendocalcaneus (Achilles tendon) was transected and repaired, rabbit right hindlimbs were immobilized with the ankle plantar flexed and the knee flexed to 90 degrees. Rabbits were maintained in the cast and sacrificed at 5, 15, or 21 days postoperatively or the cast was removed on day 5 and the animals sacrificed at day 15 or 21. SOL, PLN, and GST muscles of both limbs were removed and weighed, and then histochemical analyses were performed on SOL and PLN muscles. Immobilization decreased SOL muscle wet weights, mean fiber cross-sectional area, and percentage of Type I fibers and increased the percentage of Type IIc fibers. Ten days after cast removal (i.e., postoperative day 15), SOL muscle atrophy and fiber composition did not differ significantly from continuously immobilized controls. However, 16 days after cast removal (i.e., postoperative day 21), SOL muscle fiber cross-sectional area and fiber composition were near normal, differing significantly from continuously casted controls. At each of the time intervals studied, PLN (containing many glycolytic fibers) did not atrophy as much as SOL (containing mainly oxidative fibers). Our results indicate that 1) early cast removal prevents atrophy of PLN glycolytic fibers, but not oxidative fibers in either PLN or SOL, and 2) early cast removal promotes recovery from atrophy of both oxidative and glycolytic fibers. In spite of the many differences between rabbits and humans, these findings suggest that, although early cast removal may not prevent oxidative muscle fiber atrophy after postoperative immobilization, it may facilitate recovery from atrophy.

Achilles Tendon↗

PubMed2006

Is it possible to decrease skin temperature with ice packs under casts and bandages? A cross-sectional, randomized trial on normal and swollen ankles.

INTRODUCTION: There is a general belief that the presence of a cast or a bandage eliminates the lowering effects of skin temperature when local cold therapy applied on the surface of the cast or bandage. The purpose of this study is to determine the magnitude of temperature changes at the skin of the ankle after the application of frozen ice packs to the surface of various casts and bandages both in normal and swollen ankles. MATERIALS AND METHODS: Thirty-two healthy subjects (Group A) and 12 patients with Grade III inversion type acute ankle sprain (Group B) were randomly divided into four groups. The sensor of the digital thermometer was secured to the ankle over the anterior talo-fibular ligament in every subject before placement of a bandage or cast. Robert Jones bandage, elastic support bandage, a below-knee plaster cast and synthetic below-knee cast were applied in groups 1, 2, 3 and 4, respectively. Two frozen ice packs were placed around the cast or bandage at the level of sensor, and skin temperatures were recorded. RESULTS: The skin temperature under dressings and casts decreased significantly relative to the baseline temperatures with local cold therapy in all groups. The fall in the temperature with cryotherapy in group A showed a three-phase pattern of change between groups 1 and 2, groups 2 and 3 and groups 2 and 4 during the experiment. The fall in the skin temperature with ice packs differed significantly between groups 1 and 3, and also groups 1 and 4 from the beginning till the end of the experiment. There was no significant difference between groups 3 and 4 in terms of skin temperature fall with cryotherapy during the whole experiment. The results were similar in group B. CONCLUSION: A bandage or cast does not prevent measurable skin temperature lowering by frozen ice packs both in normal and swollen ankles.

Adult↗

PubMed2005

Fiberglass cast application.

Plaster of Paris has been largely superceded for casting in orthopedic departments by synthetic cast materials. Despite its weight, its relative brittleness, its unpopularity with patients, and its messiness in application, plaster of Paris remains the mainstay of casting in the emergency department. This is due to a combination of economic reasons, the belief that synthetic casts leave less room for swelling and its relative ease of application compared to synthetic materials. We present a technique for synthetic cast application that avoids the problems of the rapidly setting cast and therefore allows the time for less experienced hands to produce a well-fitting cast or splint. We believe that this option, which allows the patient to have a lighter synthetic cast, rather than the traditional plaster of Paris cast, will be welcomed by both the patient and physician.

Casts, Surgical↗

PubMed1996

Characterization of noble metal implant cylinders: as-received cylinders and cast interfaces with noble metal alloys.

A common procedure in the fabrication of implant prostheses is the use of premade wrought cylinders in cast frameworks. Although manufacturers outline some precautions in the use of these components, detailed information about the metal interface between cylinders and cast alloys is lacking. This article, following a previous report that compared titanium-based implant cylinders used with two different classes of cast alloys, compares conventional noble metal cylinders from three different manufacturers combined with these two classes of cast noble alloys. Analysis of the as-received cylinders revealed that the implant cylinders as a group are predominantly composed of metals commonly found in noble dental alloys, namely, platinum, palladium, gold, and silver. The interfaces created by casting both high-fusing and low-fusing alloys around the cylinders exhibited a general elemental concentration variability compared with the bulk alloy regions, but continuous concentrations for shared elements suggested alloy-cylinder compatibility. Vickers hardness values, which ranged from 212 to 276 for the as-received cylinders, decreased from 12% to 43% for the various cylinders after casting. This study suggests characteristics of an ideal cast interface that include maintenance of the cylinder and casting alloy microstructures up to the interface, absence of interfacial reaction regions, lack of porosity created by volatilization of components from either alloy or the casting process, and sufficient strength to maintain anticipated loads.

Dental Alloys↗