DOUBLE DISK TRANSDERMAL PROCESS
20170290779 · 2017-10-12
Inventors
- Gaurav Thakersi TOLIA (Morgantown, WV, US)
- Malachi PLACHTA (Morgantown, WV, US)
- Grant HENDERSON (St. Albans, VT, US)
- Brad L. BARNETT (Swanton, VT, US)
Cpc classification
B29L2031/753
PERFORMING OPERATIONS; TRANSPORTING
B32B37/12
PERFORMING OPERATIONS; TRANSPORTING
A61M2207/00
HUMAN NECESSITIES
A61K9/7084
HUMAN NECESSITIES
International classification
A61K9/70
HUMAN NECESSITIES
A61K47/10
HUMAN NECESSITIES
B29C65/00
PERFORMING OPERATIONS; TRANSPORTING
A61M37/00
HUMAN NECESSITIES
Abstract
A double disk dermal device for administration of one or more active agents to the skin or mucosa of a host, in particular a patch is described including: a) active reservoir film layer; b) a backing overlay adjacent to the active reservoir film layer extending beyond the perimeter of the reservoir layer in all directions; c) second overlay backing layer with a coating of pressure sensitive adhesive which is adjacent to the first backing overlay extending beyond the perimeter of the first backing overlay in all directions; and d) a removable release liner. A method of making the device is also provided.
Claims
1. A process for preparing a dermal device comprising the steps of: fixing a first layer to a first release liner; placing a second material adjacent to the first layer to form an active inner reservoir layer, wherein the second material brings structural integrity to the active inner reservoir layer; winding the exposed side of the active inner reservoir layer on a second release liner to form a dual release liner unit; kiss-cutting the active inner reservoir layer into suitable size patches; and laminating a backing layer extending beyond the perimeter of the active inner reservoir layer on the exposed side of the active inner reservoir layer; wherein the process is performed using a continuous manufacturing process.
2. The process of claim 1, wherein the first release liner and the second release liner are comprised of the same release coating chemistry.
3. The process of claim 1 wherein the first release liner and the second release liner are comprised of different release coating chemistry.
4. The process of claim 1, wherein the second material is a porous mesh film.
5. The process of claim 4, wherein the porous mesh film comprises a material selected from the group consisting of polyester, polypropylene, polyethylene, nylon, cellulose, acrylate, glass fiber, PET, PES, PVDF, PC, PTFE, MCE and mixtures thereof.
6. The process of claim 1, wherein the second material is a nonporous film.
7. The process of claim 6 wherein the nonporous film comprises a material selected from the group consisting of degradable and non-degradable polymer materials.
8. The process of claim 7 wherein the polymer material is selected from the group consisting of spunbound polyester fabrics, poly-ethylene, poly-caprolactone, polysaccharide based polymers, celluloses, biopolyesters, polylactids, polyesteramides, aliphatic or aromatic copolyesters, gums, chitosan, starches and mixtures thereof.
9. The process of claim 1 further comprising fixing a second layer to the second material; wherein the second material is located between the first layer and the second layer.
10. A process for preparing a dermal device comprising the steps of: coating a wet adhesive film on a first release liner; placing a second material adjacent to the wet adhesive film to form an active inner reservoir layer, wherein the second material brings structural integrity to the active inner reservoir layer; drying the active inner reservoir layer on the first release liner; winding the exposed side of the active inner reservoir layer on a second release liner to form a dual release liner unit; slitting the dual release liner unit into suitable size patches; removing the second release liner to expose one side of the active inner reservoir layer; kiss-cutting the active inner reservoir layer into suitable size patches and laminating a backing layer extending beyond the perimeter of the active inner reservoir layer on the exposed side of the active inner reservoir layer, wherein the process is performed using a continuous manufacturing process.
11. The process of claim 10, wherein the first release liner and the second release liner are comprised of the same release coating chemistry.
12. The process of claim 10 wherein the first release liner and the second release liner are comprised of different release coating chemistry.
13. The process of claim 10, wherein the second material is a porous mesh film.
14. The process of claim 13, wherein the porous mesh film contains a material selected from the group consisting of polyester, polypropylene, polyethylene, nylon, cellulose, acrylate, glass fiber, PET, PES, PVDF, PC, PTFE, MCE and mixtures thereof.
15. The process of claim 10, wherein the second material is a nonporous film.
16. The process of claim 15 wherein the nonporous film comprises a material selected from the group consisting of degradable and non-degradable polymer materials.
17. The process of claim 16 wherein the polymer material is selected from the group consisting of spunbound polyester fabrics, poly-caprolactone, polysaccharide based polymers, celluloses, biopolyesters, polylactids, polyesteramides, aliphatic or aromatic copolyesters, gums, chitosan, starches and mixtures thereof.
18. A process for preparing a dermal device comprising the steps of: coating a wet adhesive film on a first release liner; drying the wet adhesive film on the first release liner to form an active inner reservoir layer; kiss-cutting the active inner reservoir layer into suitable size patches and placing a backing ring extending beyond the perimeter of the active inner reservoir layer on the exposed side of the active inner reservoir layer, laminating the exposed side of the backing ring with an outer disk adhesive layer; wherein the process is performed using a continuous manufacturing process.
19. A process for preparing a dermal device comprising the steps of: coating a wet adhesive film on a first release liner; drying the wet adhesive film on the first release liner to form an active inner reservoir layer; laminating the active inner reservoir layer with a first backing film layer coated with an adhesive tie layer that brings structural integrity to the waste rewind; winding the exposed side of the adhesive tie layer on a second release liner to form a dual release liner unit; removing the second release liner to expose one side of the adhesive tie layer; kiss-cutting the laminated active inner reservoir layer into suitable size patches; laminating a second backing layer extending beyond the perimeter of the active inner reservoir layer on the exposed side of the adhesive tie layer; and laminating the second backing layer with an outer disk adhesive layer; wherein the process is performed using a continuous manufacturing process.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] In order to better understand various exemplary embodiments, reference is made to the accompanying drawings, wherein
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DETAILED DESCRIPTION
[0033] The present disclosure relates generally to dermal devices of double disk configuration comprising an outer disk overlay layer, which includes a backing and pressure sensitive adhesive coating, separated from the active inner disk reservoir film with a backing layer that extends in all directions of the active inner disk reservoir film and methods of making the same.
[0034] The description and drawings presented herein illustrate various principles. It will be appreciated that those skilled in the art will be able to devise various arrangements that, although not explicitly described or shown herein, embody these principles and are included within the scope of this disclosure. As used herein, the term, “or,” as used herein, refers to a non-exclusive or (i.e., or), unless otherwise indicated (e.g., “or else” or “or in the alternative”). Additionally, the various embodiments described herein are not necessarily mutually exclusive and may be combined to produce additional embodiments that incorporate the principles described herein.
[0035] The present invention is based on the finding that adhesive coated films do not have sufficient tensile strength to allow for kiss-cutting and waste rewinding in a continuous manufacturing process in order to make a double disk device configuration. It has surprisingly been found that a porous mesh membrane or a non-porous rate-controlling membrane would provide the required strength for allowing continuous manufacturing of these devices. As used herein, the term “continuous” refers to a manufacturing process wherein the process does not involve a stoppage for removal or stripping of adhesive or backing film skeletons.
[0036] One aspect of the invention features a dermal device where the inner active reservoir layer is dried during coating with a porous mesh film or a non-porous rate controlling membrane of sufficient structural integrity that would allow for continuous kiss-cutting and waste rewinding before lamination with a backing film. This feature provided by the porous mesh film and the non-porous rate controlling membrane, allows the active inner reservoir layer to be coated and dried and provides that the active inner reservoir layer would not have to be laminated to a backing immediately following drying, as would be the practice. For example, the porous mesh film or non-porous rate-controlling membrane could be the temporary backing, or the porous mesh film could be embedded in the active reservoir coating. The features provided by the porous mesh film and the non-porous rate controlling membrane include: [0037] structural integrity that would allow for continuous kiss-cutting and waste rewinding during manufacture, thereby increasing line speed and reducing defects; [0038] differential release of the active film from a release liner, which allows for the use of two release liners of the same composition to perform the continuous process of the invention; [0039] slowing the rate of seepage of the active ingredient or excipients from the active inner reservoir layer to the outer backing layers through the porous mesh film or the non-porous rate-controlling membrane, which would allow for at least temporary storage of the coated roll, allowing kiss-cutting and lamination with a backing roll, and [0040] bonding of the active reservoir layer to the backing film.
[0041] Referring to the drawings, in which like numerals refer to like components or steps, there are disclosed broad aspects of various embodiments.
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[0054] In the diagrammatic illustration of
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[0056] In the diagrammatic illustration of
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[0058] In various embodiments, the inner disk reservoir layer 221 and/or the outer disk layer 110 may be prepared using a hot melt process or a solvent based process such as solvent coating, curing or cross-linking.
[0059] In various embodiments, suitable porous mesh films include degradable or non-degradable polymeric materials, polyester, polypropylene, polyethylene, nylon, cellulose, acrylate, glass fiber, PET, PES, PVDF, PC, PTFE, MCE or mixture of material meshes. Suitable polymeric materials include synthetic polymers and bio-polymers. The porous mesh could be manufactured into a film structure which could be of different thickness or porosity depending on the functionality to be obtained from the mesh in addition to bringing structural integrity. The porous mesh could be multilayer or monolayer mesh film. The porous mesh could be polymeric or non-polymeric mesh film or could be woven or non-woven. Typical examples of useful meshes include Reemay® spunbond polyester, Typar® spunbond polypropylene, nylon mesh. Advantageous material that function as porous mesh satisfy the minimum requirement in that the tensile strength of the dried inner disk reservoir layer with mesh is greater than the tensile strength of dried inner disk reservoir layer without the mesh. The thickness of the porous mesh is based on providing sufficient integrity for processibility. The tensile strength of the porous mesh is based on providing sufficient integrity for processing in the machine direction.
[0060] In various embodiments, the active inner reservoir layer 121 can contain additional excipients that include enhancers that promote the penetration of the active agent through the skin. The enhancer may be incorporated into the active inner reservoir layer 121 by solvent blending or melt-blending. Suitable enhancers include monovalent, saturated and unsaturated aliphatic and cycloaliphatic alcohols having 6 to 12 carbon atoms such as cyclohexanol, lauryl alcohol and the like; aliphatic and cycloaliphatic hydrocarbons such as mineral oils; cycloaliphatic and aromatic aldehydes and ketones such as cyclohexanone; N,N-di (lower alkyl) acetamides such as N,N-diethyl acetamide, N,N-dimethyl acetamide, N-(2-hydroxyethyl) acetamide, and the like; aliphatic and cycloaliphatic esters such as isopropyl myristate and lauricidin; N,N-di (lower alkyl) sulfoxides such as decylmethyl sulfoxide; essential oils; nitrated aliphatic and cycloaliphatic hydrocarbons such as N-methyl-2-Pyrrolidone, Azone; salicylates, polyalkylene glycol silicates; aliphatic, keto or aromatic acids such as oleic acid and lauric acid, terpenes such as cineole, surfactants such as sodium lauryl sulfate, siloxanes such as hexamethyl siloxane; mixtures of the above materials; and the like.
[0061] In various embodiments, suitable non-porous rate-controlling membranes include degradable or non-degradable polymeric materials such as spunbound polyester fabric. Suitable polymeric materials include synthetic polymers and bio-polymers. Other examples of degradable polymers are poly-caprolactone, polysaccharide based polymers, celluloses, biopolyesters, polylactids, polyesteramides, aliphatic or aromatic copolyesters, gums, chitosan, starches and the like.
[0062] In various embodiments, the backing layer is composed of a material or combination of materials that is substantially impermeable to the layer or layers with which it can be in contain, e.g., the active reservoir layer 121 and the active agents or ingredients contained therein. By impermeable, it is meant that the other components in contact with the backing layer or component under consideration will not appreciably permeate through such layer or component for the normal period of use and storage of the device. Some suitable materials for the backing layer include, for example, cellophane, cellulose acetate, ethyl cellulose, plasticized vinyl acetate-vinyl chloride copolymers, ethylene-vinyl acetate copolymer, polyethylene terephthalate, polyvinyl chloride, nylon, polyethylene, polypropylene and polyvinylidene chloride (e.g., SARAN) and polyolefin.
[0063] In various embodiments, the release liner is composed of materials suitable for use in the backing layer provided they are active agent impermeable. Such materials as a release liner are made removable or releasable from the adhesive layers or active agent layers by, for example, conventional treatment with silicon, Teflon or other suitable coating on the surface thereof. In one embodiment, the first and second release liners utilized in the continuous process for preparing the dermal device of the invention are composed of the same release coating. In another embodiment, the first and second release liners utilized in the continuous process for preparing the dermal device of the invention are composed of different release coatings.
[0064] In various embodiments, suitable inner disk active agents include; high melting and low melting point pharmacological or non-pharmacological agents. Active agents are preferably selected from the group consisting of pharmaceutical agents that provide pharmacological action to a host and are not limited to chemical or pharmacological functionality.
[0065] In various embodiments, abuse deterrent agents may be included in the active reservoir layer 121, adhesive tie layer 626 or outer disk layer 110. Suitable abuse deterrent substances include opioid antagonists, absorbent materials, such as activated charcoal, magnesium aluminum silicate, or activated alumina; bittering agents, such as sucrose octaacetate, denatonium saccharide, denatonium benzoate, caffeine, quinine (or a quinine salt such as quinine sulfate), bitter orange peel oil, and other botanical extract ingredients, such as pepper extract (Cubeb), capsicum, and the like and indicator dyes, such as allura red, amaranth, brilliant blue, canthaxanthin, carmine, carmoisine, carotene, curcumin, erythrosine, green S, indigo carmine, iron oxide black, iron oxide red, iron oxide yellow, patent blue, phloxine O, ponceau 4R, quinoline yellow, riboflavin, sunset yellow, tartrazine, titanium dioxide, vegetable carbon black, and other natural colors such as annatto, beet, black carrot, black currant, caramel, carmine, carmine lake, chlorophyll, cochineal, elderberry, grapeskin/grape juice, malt, paprika, red cabbage, turmeric, and anthocyanins and tonicity-increasing agents such as carbohydrates (e.g., dextrose, lactose, etc.), salts, mannitol, urea, acids (e.g., tartaric acid), and combinations thereof. The substances are to be incorporated into the dosage forms of the abuse-potential drugs in such a manner that the deterrent substance does not exhibit its deterrent effect when a dosage form of the drug is properly administered, but exhibits a deterrent effect when the dosage form is chewed, crushed or chemically extracted for nasal (snorting), inhalation (smoking), oral, buccal or sublingual administration or injected.
[0066] The inner disk active reservoir layer may include a reservoir of pressure sensitive adhesive or non-adhesive polymeric matrices which provide active agent release when administrated to a host. Suitable pressure sensitive adhesives provide physical and chemical stability and are selected based on the properties of the active agent. For example, silicone adhesives with reduced hydroxy groups would be preferred for amine group-containing active agents.
[0067] In various embodiments, suitable pressure-sensitive adhesive materials include some natural rubber and synthetic rubber adhesives and cross-linkable laminating adhesives. Examples of suitable natural rubber adhesives include R-1072 from B.F. Goodrich Co., No. 735 from C.L. Hathaway, and No. 5702 from Evans St. Clair. Examples of synthetic rubber adhesives include Jowatherem 270-00 and Jowatherem S-3202 from Jowat Corp. and 70-9416 from National Starch. Other suitable laminating adhesives include the Dow Corning laminating silicone adhesives and the Lord Corporation Tycel 7900 series laminating adhesives. Also contemplated are acrylic copolymers such as those available from National Starch and Chemical Co. of Bridgewater, N.J. under the marks DURO-TAK 87-2516 and DURO-TAK 87-2287. The adhesives most impermeable to most active ingredients are cross-linkable laminating adhesives, which are well-known to those of ordinary skill in the art.
[0068] The active agent adhesive layers may be pressure-sensitive adhesives. Any of the well-known, dermatologically acceptable, pressure-sensitive adhesives which permit drug migration therethrough can be used in the present invention. Some suitable permeable adhesives include acrylic or methacrylic resins such as polymers of alcohol esters of acrylic or methacrylic acids and alcohols such as n-butanol, is opentanol, 2-methylbutanol, 1-methyl-butanol, 1-methyl-pentanol, 2-methylpentanol, 3-methylpentanol, 2-ethyl-butanol, isooctanol, n-decanol, or n-dodecanol, alone or copolymerized with ethylenically unsaturated monomers such as acrylic acid, methacrylic acid, acrylamide, methacrylamides, N-alkoxymethyl acrylamides, N-alkoxymethyl methacrylamides, N-t-butyl-acrylamide, itaconic acid, vinyl acetate, N-branched alkyl maleamic acids wherein the alkyl group has 10-24 carbon atoms, glycol diacrylates, or mixtures of these monomers; polyurethane elastomers; vinyl polymers such as polyvinyl alcohol, polyvinyl ethers, polyvinyl pyrrolidone, and polyvinyl acetate; urea formaldehyde resins; phenol formaldehyde resins, resorcinol formaldehyde resins; cellulose derivatives such as ethylcellulose, methylcellulose, nitrocellulose, cellulose acetate butyrate and carboxymethylcellulose; and natural gums such as guar, acacia, pectina, starch, destria, gelatin, casein, etc.
[0069] Other suitable pressure-sensitive adhesives include polyisobutylene pressure sensitive adhesives, rubber pressure-sensitive adhesives, cross-linked adhesives, silicone pressure-sensitive adhesives or combination of adhesives. The adhesives may also be compounded with tackifiers and stabilizers as is well-known in the art. Adhesives that are preferred for their active agent permeability include acrylic copolymer adhesives such as Avery Chemical Company's AS-351 HSX, preferably at a coating weight of between 75 and 125 g/m.sup.2. This pressure-sensitive adhesive is a cross-linkable polymer which provides a permanently tacky film having a total solids content of about 52%, Brookfield viscosity (LVT/Spindle No. 4/12 RPM @ 25′C) of from about 15,000 to 25,000 cps. at a weight per gallon of about 7.4 lbs. It can also be diluted with hexane or toluene to a desired solids and/or viscosity range, particularly for use in conventional coating equipment.
[0070] Other such adhesives that can also be used for these purposes include an acrylic pressure-sensitive adhesive sold by National Starch and Chemical Co. under the designation DURO-TAK 80-1054. This adhesive has a solids content of 47.5%, a viscosity of 3,000 cps., and plasticity (Williams) of 2.9 mm. It is generally used with a solvent system including ethyl acetate, heptane, isopropyl alcohol and toluene. Another such adhesive is sold by the UCB Group under the designation GELVA Multipolymer Emulsion 2484, and comprises a stable aqueous acrylic emulsion pressure-sensitive adhesive having a solids content of 59% and a viscosity of 1,500 to 2,300 cps. Examples of other acrylic adhesives include Gelva 788 and 733 from UCB, PS-41 from C.L.-Hathaway, Vr-0833 from H.B. Fuller, Adcot 73A207A from Morton Chemical, Nos. 80-2404, 80-1054, 72-9056 and 72-9399 from National Starch, Nos. E-2015, E-2067 and E-1960 from Rohm & Haas, M-6112 from Uniroyal, Inc. and Daratak 74 L from W.R. Grace. Suitable rubber adhesives include Duro-Tak 36-6172 from National Starch and Morstik 118 from Morton Chemical. An example of a suitable silicone adhesive is 7-4502 from Dow Corning. Adhesive polymers are preferably selected based on suitable product design to minimize residual drug and are not limited to adhesive chemical functionality.
[0071] Although the various exemplary embodiments have been described in detail with particular reference to certain exemplary aspects thereof, it should be understood that the invention is capable of other embodiments and its details are capable of modifications in various obvious respects. As is readily apparent to those skilled in the art, variations and modifications can be affected while remaining within the spirit and scope of the invention. Accordingly, the foregoing disclosure, description, and figures are for illustrative purposes only and do not in any way limit the invention, which is defined only by the claims.
[0072] In various embodiments, suitable outer disk layers consist of a backing, at least one adhesive layer and removable release liner. Suitable materials for outer disk layer backing include woven or non-woven, fabric, spun-laced, spun-bonded, multi-layered, porous or non-porous materials. Suitable adhesive include solvent coated-cross-linked, un-crosslinked, cross-linkable or thermos-plastic adhesives. The adhesives are preferably selected from groups that provide comfortable and adequate wear characteristics and not limited to chemical functionality of the adhesive or mixtures of adhesives.
[0073] The removable release liner suitable for the system include but is not limited to silicone coated, fluoro-carbon coated, uv cross-linked, epoxy coated liners suitable for providing low peel force selected based on the adhesive choice of the inner and outer disk layer and not limited to chemical functionality or the substrate.
Example 1
[0074] In the following example, a study was conducted to compare various double disk transdermal systems in regards to the migration of excipients into the outer adhesive overlay from the inner reservoir layer. Transdermal systems Sample 2 and Sample 4 are representative embodiments of the dermal devices of the invention.
[0075] In this study, a placebo inner reservoir film was used containing enhancer and plasticizer excipients. The inner reservoir film was prepared by weighing 13.205 gm of ethyl acetate, 28.5 gm of ethanol, 6.5 gm of enhancer, 13 gm of plasticizer, 10 gm of Povidone and 128.7 gm of Duro-Tak acrylate adhesive solids. The blend was mixed overnight and coated on a suitable release liner and dried in ovens to obtain a nominal coat weight of 80 g/m.sup.2. Portion of the dried laminate were either laminated with a PET backing or were laminated with a second release liner to produce the gap design devices (Sample 2 and Sample 4). The portion of the laminate with was laminated on PET backing was die cut and the backing side was placed on the outer adhesive overlay. The outer adhesive overlay was die cut and the inner disk release liner was removed to obtain the double disk design where the inner disk reservoir would be in contact with the outer disk adhesive overlay (Sample 3 and sample 5). For the portion of the laminate which was made to produce the oversized backing Gap design devices of the invention, the inner disk reservoir was die cut and placed on a PET backing film after the release liner was removed. The PET backing film was die cut to a size larger than the inner disk reservoir film. The backing side of the die cut film was adhered to the outer disk adhesive overlay. This resulted in the inner disk not being in contact with the outer disk adhesive overlay in all directions. The finished systems were stored for 1 month at 60° C. in an oven and the outer disk was separated from the inner disk reservoir to determine the extent of migration of enhancer and plasticizer.
[0076] Specific designs tested for migration of excipients in the outer adhesive overlay from the inner reservoir layer:
[0077] Excipient migration from inner disk to outer disk study (oversized backing and double disk design comparison)
Sample 1—Placebo inner disk only (PET backing, 80 g/m.sup.2, removable release liner)
Sample 2—oversized backing design (Placebo inner disk on larger area PET backing, with, outer disk acrylate adhesive 1 layer)
Sample 3—double disk design—(Placebo inner disk on same sized PET backing, on, outer disk acrylate adhesive 1 layer)
Sample 4—oversized backing design (Placebo inner disk only on larger area PET backing, on outer disk acrylate adhesive 2 layer)
Sample 5—double disk design (Placebo inner disk on same sized PET backing, on outer disk acrylate adhesive 2 layer).
[0078] Enhancer Assay
TABLE-US-00001 Initial 1 month Sample 2 (Oversized) Inner Disk 112.1% 87.9% Outer Disk 5.3% Total 93.2% Sample 3 Inner Disk 112.1% 75.2% Outer Disk 8.1% Total 83.3% Sample 4 (Oversized) Inner Disk 112.1% 83.3% Outer Disk 5.7% Total 89.0% Sample 5 Inner Disk 112.1% 73.8% Outer Disk 8.0% Total 81.8%
[0079] Plasticizer Assay
TABLE-US-00002 Initial 1 month Sample 2 (Oversized) Inner Disk 118.9% 111.6% Outer Disk 1.6% Total 113.2% Sample 3 Inner Disk 118.9% 101.8% Outer Disk 5.7% Total 107.5% Sample 4 (Oversized) Inner Disk 118.9% 112.6% Outer Disk 1.9% Total 114.5% Sample 5 Inner Disk 118.9% 91.9% Outer Disk 9.0% Total 100.9%
[0080] The results demonstrate that the oversized backing devices of the invention had lower migration of excipients compared to the conventional double disk design. The migration of enhancer in the outer adhesive overlay at 1 month, 60° C. was 5.3% for the oversized backing design compared to 8.1% for conventional double disk design. The migration of plasticizer in the outer adhesive overlay at 1 month, 60° C. was 1.6% for the oversized backing design compared to 5.7% for the conventional double disk design systems.