Forums
New posts
Search forums
What's new
New posts
Latest activity
Articles
Members
Current visitors
Log in
Register
What's new
Search
Search
Search titles only
New posts
Search forums
Menu
Log in
Register
Install the app
Install
Forums
Community discussion
Implants
Custom abutments help!
JavaScript is disabled. For a better experience, please enable JavaScript in your browser before proceeding.
You are using an out of date browser. It may not display this or other websites correctly.
You should upgrade or use an
alternative browser
.
Reply to thread
Message
<blockquote data-quote="dmonwaxa" data-source="post: 45195" data-attributes="member: 927"><p>@Labwa</p><p></p><p></p><p>Its really great to know what others are doing to address a particular situation, ie porcelain application. In this case however, its clear that the problem was with a full cast crown; leaving the wax-up short or creating a ditch short of the collar on the cast to abt does not help in this situation. I really dont think that clients would accept this type of workmanship on this type of restoration. Sure you can fudge it by covering with porcelain on a screw retained pfm but not so on full gold. So how does one elimate the flash problem? There are many was to skin this cat, but first I think one has to understand materials and the techniques involved. </p><p></p><p>Some abutment designs on cast to's may encourage flashing. Cleaning with alcohol adds another element into the equation and one may actually inadvertently leave a flash of wax in the collar of the UCLA, unseen by the naked eye and leads to flashing. Solution? Be immaculate when waxing by keeping wax off the collar.</p><p></p><p>Secondly, understanding materials. Investments are formulated to create a certain percentage of expansion, and this is controlled by the special liquid. </p><p>Since the metal component of the machined UCLA will not expand as will wax in the invested ring a space will exist between the machined parts and the investment when heat treated during burn out. No expansion is necesary for cast to UCLA's as you would with a crown. One should not be concerned with tight fits with UCLA's as with a conventional crown since the parts are already pre machined to fit prior to casting. So, my solution for flashing on UCLA's? Use less special liquid for investing. Same applies for cast to screw retained PFMs.</p><p></p><p><img src="/forums/images/smilies/test/cheers.gif" class="smilie" loading="lazy" alt="Cheers" title="Cheers Cheers" data-shortname="Cheers" /></p></blockquote><p></p>
[QUOTE="dmonwaxa, post: 45195, member: 927"] @Labwa Its really great to know what others are doing to address a particular situation, ie porcelain application. In this case however, its clear that the problem was with a full cast crown; leaving the wax-up short or creating a ditch short of the collar on the cast to abt does not help in this situation. I really dont think that clients would accept this type of workmanship on this type of restoration. Sure you can fudge it by covering with porcelain on a screw retained pfm but not so on full gold. So how does one elimate the flash problem? There are many was to skin this cat, but first I think one has to understand materials and the techniques involved. Some abutment designs on cast to's may encourage flashing. Cleaning with alcohol adds another element into the equation and one may actually inadvertently leave a flash of wax in the collar of the UCLA, unseen by the naked eye and leads to flashing. Solution? Be immaculate when waxing by keeping wax off the collar. Secondly, understanding materials. Investments are formulated to create a certain percentage of expansion, and this is controlled by the special liquid. Since the metal component of the machined UCLA will not expand as will wax in the invested ring a space will exist between the machined parts and the investment when heat treated during burn out. No expansion is necesary for cast to UCLA's as you would with a crown. One should not be concerned with tight fits with UCLA's as with a conventional crown since the parts are already pre machined to fit prior to casting. So, my solution for flashing on UCLA's? Use less special liquid for investing. Same applies for cast to screw retained PFMs. Cheers [/QUOTE]
Insert quotes…
Verification
Who do we work for?
Post reply
Forums
Community discussion
Implants
Custom abutments help!
Top
Bottom