Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
DETAILED ACTION
This Office action is in response to the communication filed on 02/02/2026. Currently claims 1-19 are pending in the application; with claims 18-19 withdrawn from consideration.
Claim Rejections - 35 USC § 102
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
The following is a quotation of the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action:
A person shall be entitled to a patent unless –
(a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale or otherwise available to the public before the effective filing date of the claimed invention.
(a)(2) the claimed invention was described in a patent issued under section 151, or in an application for patent published or deemed published under section 122(b), in which the patent or application, as the case may be, names another inventor and was effectively filed before the effective filing date of the claimed invention.
Claims 1, 3, and 5 are rejected under 35 U.S.C.102 as being anticipated over Rampf et al (US Patent Application Publication Number 2024/0300851 A1), hereafter, referred to as “Rampf”. It is noted that Rampf qualifies as prior art under 35 U.S.C. 102(a)(2), as it is an application for patent published under 122(b), names another inventor, and was effectively filed before the effective filing date of the claimed invention. Regarding the latter, it is the national phase filing of PCT/EP2022/054010 that was filed on 2/17/2022 (and claims to an EP filing dated 2/24/2021) and designating the U.S. and, therefore, was effectively filed prior to the earliest effective filing date of 11/08/2022 of the present invention.
Regarding claim 1, Rampf teaches a method of producing a multicolored glass-ceramic blank for dental purposes (para. [0061] [0068-0069], comprising at least a first material powder and a second material powder, wherein the first material powder and the second material powder are different-colored (para. [0061], wherein the method comprises:
introducing the first material powder and the second material powder into a mold, in order to form at least one powder mixture aggregate (para. [0056-0057], [0061]), and
compressing the powder mixture aggregate by hot pressing to form the glass-ceramic blank (para. [0066] [0070]).
Rampf also teaches that at least one of first material powder and second material powder comprises nanoparticles and/or glass-ceramic particles; by teaching that the invention relates to a process for production the glass ceramic with quartz solid solution phase, in which the starting glass or the starting glass with nuclei, in particular in particulate form, preferably in the form of a powder and particularly preferably in the form of a powder compact, is subjected to at least one heat treatment (para. [0065]). Rampf teaches that the starting glass comprises nuclei for the crystallization of quartz solid solution phase and nuclei for the crystallization of lithium disilicate or lithium-metasilicate (para. [0058], claim 18). The nuclei for crystallization would be considered to be nanocrystals (or more generally, nano-sized crystalline seeds/clusters) (equivalent to nanoparticles) by a person of ordinary skill in the art.
Regarding claim 3, Rampf teaches a method of producing a multicolored glass-ceramic blank for dental purposes, further comprising heat treatment of the powder mixture aggregate (para. [0062-0063]).
Regarding claim 5, Rampf teaches a method of producing a multicolored glass-ceramic blank for dental purposes, wherein, in the compressing of the powder mixture aggregate by hot pressing, the powder mixture aggregate is positioned in the mold (para. [0066-0070]).
Claim Rejections - 35 USC § 103
The following is a quotation of the appropriate paragraphs of 35 U.S.C. 103 that form the basis for the rejections under this section made in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or non-obviousness.
This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention.
Claims 2, 4, 6-17 are rejected under 35 U.S.C.103 as being obvious over Rampf et al (US Patent Application Publication Number 2024/0300851 A1), in view of Arnold et al. (US Patent Application Publication Number 2020/0317561 A1), hereafter, referred to as “Arnold”.
Regarding claim 2, Rampf teaches a method of producing a multicolored glass-ceramic blank for dental purposes (para. [0061] [0068-0069], comprising at least a first material powder and a second material powder, wherein the first material powder and the second material powder are different-colored (para. [0061]. Rampf also teaches that by using several differently colored powders, multicolored blanks can be obtained in a simple manner, which have several areas with different color properties. But Rampf fails to explicitly teach that the first material powder and the second material powder are introduced into the mold in locally different mixing ratios, to result in a color progression in the glass-ceramic blank. However, Arnold teaches in a process for the manufacturing of multi-coloured glass-ceramic blanks, that the powders or suspensions are introduced into the mould in such a way that the multi-coloured glass ceramic blank prepared has a continuously changing colour (claim 4). Therefore, it would have been obvious to a person of ordinary skill in the art at the time of filing the claimed invention, to incorporate the teaching of Arnold and use a known technique, to introduce the first material powder and the second material powder into the mold in locally different mixing ratios, to result in a color progression in the glass-ceramic blank to improve the natural appearance of a dental appliance (KSR Rationale C, MPEP 2143). Since both the references deal with preparation of glass-ceramic blanks for dental purpose, one would have reasonable expectation of success from the combination.
Regarding claim 4, Rampf teaches a method of producing a multicolored glass-ceramic blank for dental purposes (para. [0061] [0068-0069], comprising at least a first material powder and a second material powder, wherein the first material powder and the second material powder are different-colored (para. [0061]. Both Rampf and Arnold teach the use of heat treatment after the powder materials are introduced into the mould. It is well known to an ordinary artisan that thermal treatment does lead to the rounding of particles, a process driven by the thermodynamic principle of minimizing surface energy. Irregularly shaped particles have a higher surface area-to-volume ratio than spheres, making them less stable. Heating provides the energy for material to redistribute and eliminate sharp corners and edges, pushing the particle toward a more stable, spherical shape. Therefore, it would have been obvious to a person of ordinary skill in the art at the time of filing the claimed invention, that the material powders would comprise of rounded glass particles, rounded nanoparticles and/or rounded glass-ceramic particles after the heat treatment process.
Regarding claims 6-7, Rampf teaches a method of producing a multicolored glass-ceramic blank for dental purposes (para. [0061] [0068-0069], comprising at least a first material powder and a second material powder, wherein the first material powder and the second material powder are different-colored (para. [0061]. Both Rampf and Arnold teach the use of heat treatment and hot pressing process in the preparation of glass-ceramic dental blanks. Additionally, Arnold explicitly teaches in claim 1, that the material is heat treated first (step c), followed by the hot pressing process (step d) after the material powders is introduced in the mould (step a). Arnold also teaches that it is preferred to carry out the heat treatment at a temperature of less than 700 °C (para. [0048]); and further teaches that it is preferred that the hot pressing is effected at a temperature, in particular 700 to 750 °C, and at a pressure of in particular from 5 to 50 MPa (para. [0052]). Therefore, it would have been obvious to a person of ordinary skill in the art that the powder mixture aggregate is first heated to a temperature of at least 700 °C and then a compression force (F) is applied, wherein the attainment of the temperature of at least 700 °C is used as trigger criterion for the applying of the compression force (F), based on the teaching of Arnold and the claimed sequence in claim 1.
Regarding claim 8, Arnold teaches in the process for the manufacturing of the multi-coloured glass-ceramic blanks, that the compaction surprisingly succeeds in giving the glass ceramic blank a density which does not differ substantially from the density of a glass ceramic blank produced in a conventional manner by the solid glass technology (para. [0050]). Therefore, it would have been obvious to a person of ordinary skill in the art at the time of filing the claimed invention, that the powder mixture aggregate is compressed by hot pressing to a density of at least 99 .9% of a base material of the first material powder and/or of a base material of the second material powder.
Regarding claim 9, Rampf teaches a method of producing a multicolored glass-ceramic blank for dental purposes (para. [0061] [0068-0069], comprising at least a first material powder and a second material powder, wherein the first material powder and the second material powder are different-colored (para. [0061]. Rampf also teaches that by using several differently colored powders, multicolored blanks can be obtained in a simple manner, which have several areas with different color properties. But Rampf fails to explicitly teach that the first material powder and the second material powder are introduced into the mold at least two separate sites in the mold in order to form at least two powder mixture aggregates. However, Arnold teaches in a process for the manufacturing of multi-coloured glass-ceramic blanks, by differently coloured powders, in different variants, powders with different compositions which, during further processing via the glass-ceramic blank prepared to form the dental restoration, produce regions with different colours in the dental restoration (para. [0022]). Therefore, it would have been obvious to a person of ordinary skill in the art at the time of filing the claimed invention, to incorporate the teaching of Arnold and use a known technique, to introduce the first material powder and the second material powder are introduced into the mold at least two separate sites in the mold in order to form at least two powder mixture aggregate to produce regions with different colours in the dental restoration (KSR Rationale C, MPEP 2143). Since both the references deal with preparation of glass-ceramic blanks for dental purpose, one would have reasonable expectation of success from the combination.
Regarding claim 10-11, Arnold teaches in a process for the manufacturing of multi-coloured glass-ceramic blank for dental purpose, wherein the powder mixture aggregate is compressed by hot pressing at a temperature of 650° C to 780° C and at a pressure of 5 MPa to 50 MPa (as claimed in claim 10), and at a temperature of 700 °C to 750 °C, and at a pressure of 10 MPa to 30 MPa (as claimed in claim 11); by teaching that it is preferred that the hot pressing is effected at a temperature of from 650 to 780 °C, in particular 700 to 750 °C, and at a pressure of in particular from 5 to 50 MPa, preferably 10 to 30 MPa (para. [0052]).
Regarding claim 12-13, Rampf teaches in a process for the manufacturing of multi-coloured glass-ceramic blank for dental purpose, wherein the powder mixture aggregate is compressed by hot pressing for a duration of 0.1 minute to 10 minutes (as claimed in claim 12), and for a duration of 0.3 minute to 5 minutes (as claimed in claim 13); by teaching that the powder material is subjected to at least one heat treatment in the range from 600 to 1000 °С, preferably 650 to 900° C, for a duration of in particular 1 to 240 min, preferably 5 to 120 min and particularly preferably 10 to 60 min (para. [0065])
Regarding claim 14-15, Rampf teaches in a process for the manufacturing of multi-coloured glass-ceramic blank for dental purpose, wherein the powder mixture aggregate is compressed by hot pressing at an atmospheric pressure of less than 0.1 bar (as claimed in claim 14, and at an atmospheric pressure of 0.01 bar to 0.08 bar (as claimed in claim 15); by teaching that the hot pressing is effected at an atmospheric pressure of less than 0.1 bar and preferably at 0.01 to 0.08 bar (para. [0054]).
Regarding claim 16, Arnold teaches a process for the manufacturing of multi-coloured glass-ceramic blank for dental purpose, to produce a glass ceramic blank from which dental restorations with excellent optical and mechanical properties can be produced (para. [0053]). Therefore, it would have been obvious to a person of ordinary skill in the art that the method would produce glass-ceramic blank, which is a multiple blank, as multiple dental restorations cand be produced.
Regarding claim 17, Arnold teaches a process for the manufacturing of multi-coloured glass-ceramic blank for dental purpose, wherein the mould used is in particular comprised of several parts in order to facilitate the simple removal of the blank formed from the mould (para. [0040]). Therefore, it would have been obvious to a person of ordinary skill in the art at the time of filing the claimed invention, that the process would further comprise of opening the mold and removing the glass-ceramic blank.
Responses to Arguments
Applicant’s argument filed on 02/02/2026 for the 102 rejections has been fully considered. Applicant’s argument with respect to claim 1 has been carefully considered, but is not persuasive. The Applicant argues that the claimed invention requires that at least one of the starting powders comprises nanoparticles and/or glass-ceramic particles, and Rampf fails to teach the above limitation. However, as has been explained in the rejection section, Rampf teaches that at least one of first material powder and second material powder comprises nanoparticles and/or glass-ceramic particles; by teaching that the invention relates to a process for production the glass ceramic with quartz solid solution phase according to the invention, in which the starting glass or the starting glass with nuclei, in particular in particulate form, preferably in the form of a powder and particularly preferably in the form of a powder compact, is subjected to at least one heat treatment (para. [0065]). Rampf teaches that the starting glass comprises nuclei for the crystallization of quartz solid solution phase and nuclei for the crystallization of lithium disilicate or lithium-metasilicate (para. [0058], claim 18). The Examiner takes the position that the nuclei for crystallization would be considered to be nanocrystals (or more generally, nano-sized crystalline seeds/clusters) (equivalent to nanoparticles) by a person of ordinary skill in the art. Therefore, the Examiner maintains that based on the teaching of Rampf, the rejection set forth in this office action address the scope of the claim, and is relevant.
Because the rejections are being maintained on the amended independent claims, and since there is no substantive arguments on the rejections against the references applied against rest of the dependent claims, these rejections are being maintained.
Conclusion
Applicant’s amendment necessitated the rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any extension fee pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the date of this final action.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to MOHAMMAD M AMEEN whose telephone number is (469) 295 9214. The examiner can normally be reached on M-F from 9.00 am to 6.00 pm (Central Time).
Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Christina Johnson can be reached on (571) 272-1176. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
Information regarding the status of an application may be obtained from the Patent Application Information Retrieval (PAIR) system. Status information for published applications may be obtained from either Private PAIR or Public PAIR. Status information for unpublished applications is available through Private PAIR only. For more information about the PAIR system, see http://pair-direct.uspto.gov. Should you have questions on access to the Private PAIR system, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative or access to the automated information system, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000.
/MOHAMMAD M AMEEN/Primary Examiner, Art Unit 1742
Prosecution Insights