What's the difference between porous and pumice?

Porous


Definition:

  • (n.) Full of pores; having interstices in the skin or in the substance of the body; having spiracles or passages for fluids; permeable by liquids; as, a porous skin; porous wood.

Example Sentences:

  • (1) Recently reported unfavorable clinical results (i.e., a high incidence of pain) have led to the discontinuation of one trial of porous polyethylene.
  • (2) A porous structure, possibly involving a capsid and RNA complex, is envisioned.
  • (3) The commonly used line-to-line reaming technique was compared to an underreaming technique using both four-fifths and one-third porous-coated anatomic medullary locking (AML) implants.
  • (4) A novel type of ion exchanger was prepared by multipoint covalent binding of polystyrene chains onto the surface of porous silica followed by polymer-analogous modification of the bonded layer.
  • (5) On the buccal and lingual aspects of the implants, both the absolute lengths and CLF were significantly smaller for the porous-coated design.
  • (6) The usefulness of porous tarflen materials (tarflen--Polish name of teflon produced by Zakłady Azotowe in Tarnów, Poland) for this application was evaluated by comparing their properties with those of American porous teflon membranes used in membrane oxygenators.
  • (7) Epidermal growth factor added to cultures on solid or porous supports caused proliferation of epithelial-type cells to give a confluent monolayer but did not increase the expression of differentiated function.
  • (8) Porous polyethylene was thus better incorporated into the soft tissues than silicone rubber as long as the overlying soft tissues were not stressed by an oversized implant or inadequate soft tissue coverage.
  • (9) In earlier studies, we have shown that porous (60 micron internodal distance) PTFE grafts develop a complete endothelial layer 2 weeks after being implanted in baboons.
  • (10) The N supplements had no significant effects on rumen pH, concentrations of volatile fatty acids, their molar proportions or the disappearance of DM or N from porous synthetic-fibre bags.
  • (11) The authors conclude that a very open luminal surface structure, and a high wall porosity, are significant factors of graft patency in small diameter vascular prostheses made of a porous material.
  • (12) Monday’s budget request, an increase of 2.2% on last year, demonstrates a shift in Japan’s security emphasis from its northern maritime border with Russia to its long and porous southern reaches.
  • (13) This theoretical analysis is in excellent agreement with experimental data obtained with glucose oxidase immobilized on a porous collagen membrane.
  • (14) The porous implant volume sampled within 2.5 mm of underlying cortex contained 33.0% HA matrix and 35.7% bone.
  • (15) Interactions among the important constituents of the fibrocartilage matrix cause meniscal tissue to behave as a fiber-reinforced, porous, permeable composite material similar to articular cartilage, in which frictional drag caused by fluid flow governs its response to dynamic loading.
  • (16) These cases show that rigid fixation with good bony ingrowth does not guarantee the clinical success of a porous-coated uncemented femoral stem.
  • (17) The linear solvent strength model of Snyder was applied to describe fast protein separations on 2.1-micron non-porous, silica-based strong anion exchangers.
  • (18) The regional-development of heterotopic bone around the hip and the influence of postoperative prophylaxis with antiinflammatory drugs were studied in 66 patients treated with 74 noncemented, porous-coated total hip arthroplasties (THA) using the McFarland approach.
  • (19) A new process of plasma-spraying hydroxyapatite--an entirely biocompatible, bioceramic material--onto porous, titanium alloy components promotes bone ingrowth into the components resulting in implant fixation, which is superior to current methods of cemented or cementless fixation.
  • (20) The mechanical strength of the porous coating on the prosthetic surface should be improved and the prosthesis should be tested in limited clinical studies before cementless fixation can be recommended.

Pumice


Definition:

  • (n.) A very light porous volcanic scoria, usually of a gray color, the pores of which are capillary and parallel, giving it a fibrous structure. It is supposed to be produced by the disengagement of watery vapor without liquid or plastic lava. It is much used, esp. in the form of powder, for smoothing and polishing. Called also pumice stone.

Example Sentences:

  • (1) A new method, not previously recommended, involving the use of a green rubber wheel followed by pumice or composite finishing paste was similarly examined and found to come closest to restoring the original, natural enamel surface.
  • (2) Radiograms of the cranium show a "pumice-stone" appearance of the dome and deformation of the sella turcica.
  • (3) This layer can be removed by thorough pumicing or by grinding.
  • (4) Also, fewer bacteria were recovered from vigorously-pumiced, molar-tooth surfaces 24 h after application of albumin compared to buffer-treated controls.
  • (5) Ragwheels and pumice samples were collected and cultured, the results of which mandate the need for infection control guidelines for the dental laboratory.
  • (6) Scanning electron micrographs, surface profile tracings, surface roughness recordings, and statistical analysis of data support the finding that the best surface finish is obtained when sandblasting, hard stone, medium abrasive disk, second sandblasting, electropolishing, hard rubber point, hard felt disk with pumice slurry, and felt disk and soft brush with polishing paste are used progressively.
  • (7) Finishing was done with wet pumice and cup, wet pumice and a brush, a grit rubber polishing point, and an aluminum oxide- coated disc.
  • (8) Method I consisted of green stone, followed in sequence by finishing bur and pastes of pumice, powdered chalk, and SnO2.
  • (9) Various abrasive materials, such as pumice, polyethylene, and aluminum oxide are widely used as adjuncts in the therapy of acne.
  • (10) Pumice and air-powder polishing gave a similar reduction of the sonic scaling roughness.
  • (11) The occlusal surface was (1) air polished for 20 seconds, (2) cleaned with pumice for 20 seconds, or (3) not cleaned.
  • (12) All patients received a subgingival scaling and pumice by a hygienist every 6 months.
  • (13) Test teeth were cleaned with pumice and 10% alcohol, air-dried, and insulated at the approximal surfaces with strips of rubber dam.
  • (14) Thus, pumicing is a necessary final step with all removal procedures studied.
  • (15) The mean CO2 output during anaesthesia in paralyzed patients can be monitored by continuous capnographic analysis of the total exhaled gases, the latter being mechanically integrated by pumice canisters.
  • (16) Food particles (wheat flour, fishmeal or yeast) were ingested approximately 3 times faster than inert particles (kaolin, pumice or synthetic cellulose).
  • (17) However, when the surface of the etched enamel was pumiced, the enamel reacquired both the shine and appearance of non-etched enamel.
  • (18) Samples of used dental laboratory pumice from the two dental laboratories were cultured for the isolation of fungi.
  • (19) A flat enamel surface was obtained with 600-grit silicon carbide paper and cleaned with a rubber cup and a water slurry of fine flour of pumice.
  • (20) The rubbing application of a hydrochloric acid-pumice mixture has been advocated for the removal of fluorotic-like areas of permanent teeth.