Discussion Topic: Best technique for applying cement inside crown or bridge abutment

Hello! really interesting issue! because there is an increasing number of implant failure due to remaining cement. what I do, is place a retracting cord soaked with chlorhexidine, and when the abutment marging is shallow, use small amount of cement, as you do. when the abutment margin is deep, I cement the crown on an abutment exact replica, then take the crown out, and cement it to the real abutment. by making this procedure, you are certain that the cement of the crown will not overflow to risk areas. am open to better technicques for cementing, please, dear colleges, share with us!! thanks a lot.

In my experience with cement retained crowns on implants, use as little temporary cement as possible to prevent the excess of getting into the perimplant soft tissues; as well, unlike natural teeth, you do not need to worry about a complete coating to prevent possible caries. I find that temporary cement holds extremely well if the castings are well made ; and are difficult to remove. For this reason, keep the lab models that the crowns were made on, and make a note of the type of abutments used, so you can visualize exactly where the access holes to the screws are..... and if you cannot remove a crown simply by prying or gently tapping it off the implant abutment, then you can drill a small hole through the occlusal surface to access the screw, and unscrew the crown with the abutment off the implant body.......at times we send the fused ( temporarily cemented) crown-abutment to the lab where they usually break the cement bond by placing the unit in the porcelain oven to break down the cement. Gerald Rudick dds Montreal, Canada Assoc Fellow AAID ; Fellow, Diplomate, Masters ICOI

Lubricate the interior of the crown, fill with Blue Mousse, then insert a cotton swab tip (the wooden end), to make a "popsicle". When Mousse has set, pull on the swab to remove what is now the copy of the abutment or prep. Place cement into the restoration and place on the Mousse copy, then remove restoration. The excess cement remains on the copy and you can then wipe away a small amount of cement from the margin of the restoration and then deliver it, without excess cement extruding into the soft tissue. Hope this helps

Greetings, I would like to clarify first that the cement retained C&B is much superior then screw retained for the following reasons: 1. Superior seal 2. Passive fit 3. Aesthetics 4. Ease of planning The only problem with the cement retained C&B is the cement flow into the peri-implant area and the difficulty to remove the excess of the cement. But there is a solution that works 100% it calls G-Cuff. It is a small plastic ring that comes in different sizes and a measuring tool for the abutment. Super easy to use and stops absolutely the cement from flowing apically. http://www.youtube.com/watch?v=W-4IB78nm78

Hi Comments by periodoc and Juan Carlos have really answered your question. In simple words they describe a technique often referred to " extraoral cementation of implant crowns " My only comment is you want to use a temp cement of low particle size with adequate working time . Fuji Temp LT by GC designed more so for implant restorations seems to be working well in my hands compared to the traditional Zinc oxide Eugenol ( Temp bond ). Avoid Resin based cements as they don't dissolve away if extruded into the peri implant tissue and will cause more irritation. Zinc oxide , Zinc phosphate and GIC may be the safer ones to use . Be ready to raise a flap immediately if you have a lot of cement extruded into the tissues at the time of cementation . Hope this helps.

If an implant is able to be placed optimally and the restoration is created properly for exact fit, screw retained is first choice. Don't pack a cord it is damaging to the attachment and an implant can't get caries so the cement seal is not necessary. What WILl happen is that if any cement gets in the sulcus the implant will fail. An implant is not a tooth. I treat these often, it is avoidable with screw retained. The blue mousse, plumbers tape technique outside of the mouth on an implant analog is a good way to go if you must cement. Screws are retrievable also.

Dentists should know about the manufacturing process of screw retained abutments. First it is cast, its fitted manually, it is sand blasted, it is baked in the porcelain oven then it oxidized again, becomes black and burned, then it is polished with rubber abrasive instruments. The fit and the seal of such an abutment is really low. The space between the abutment and the implant filed immediately with bacteria, the poorly finished surface colonized with bacteria too. From the other hand a cement retained crown and bridges have only one problem is the cement remains, that can be easily solved bu using the G-Cuff.

Cementation has advantages over screw-retained, but retrievability with cementation is a real pain. I have decided to do away with emergence profiles since cementation inevitably leaves behind occult cement which is a timebomb for peri-implantitis. I have reverted to the time tested pontic-technology. Conventional bridges have pontics, the underside of which rests on the mucosa and any excess cement is easily removed with a floss together with a scaler. Instead of having an emergence profile which hides the crown-abutment margin within the iatrogenic pocket created by the implant, and within which excess cement is well-nigh impossible to remove especially interproximally..... I eliminate the emergence profile and opt for a pontic profile which has proven to be comparable in aesthetics. All excess cement ends up above gum i.e. between the underside of the crown and the mucosa and can be easily removed especially if cleaning grooves are incorporated on the undersurface of the crown or bridge and in between the implants. The emergence profile is a bad idea and compromises the health of the pathological periodontal pocket around the implant and we should move the crown abutment margin out of it. Look at cleaning grooves here: