Loose abutment screw will not tighten or back out: recommendations?

Try pulling on the bridge while you try removing the screw. There are occasions when the access hole that is made allows engagement of the screw hex, but not removing the screw.

-any x-rays to check for screw fracture? -is there any resin blocking the exit path or the screw? -after covering the airway, blow a puff of air down the hole & see if the screw pops out good luck

From personal experience: - double check that the screwdriver is not slipping in the screw head. Sometimes the screwdriver has been stripped or the screw has been stripped. - last resort eliminate the screw head to lift the restoration and the rest can perhaps be removed with a fine hemostat. No matter what it is easier to deal with the screw when the abutment is off. As told by a rep in the case of Implant Direct and Nobel the screws are not interchangeable and therefore there can be an issue of cross threading.

Try widening the access, or gentle with a high speed handpiece clean any debris/metal/resin around the access/orifice which could be blocking the screw from coming out.

If the hex is engaging and rotating but it won’t go up or down, the screw could be broken. This is Especially likely if it has happened before in the same screw was used to type back down.

More likely than not, the screw is not broken but bent enough after all that time when it was loose and still in function. Good luck.

Thank you all for the suggestions. I'll let you know if we have a winner..

This is a good example of why I do not like to permanently cement my crowns. Implants and abutments do not decay.why is it necessary to place a bridge that is not retrievable. In this case if temporary cement was used The bridge could easily be retrieved and the screw head would be more accessible to either screw down or back out. In any event, if the screw is bent and no longer properly engages the screw threads you could drill off the abutment and access the screw and save the implant. At that point as long as the implant is salvaged you could even retrofit the bridge with a PEEK abutment which you could adapt to the original bridge. In addition, this also gives you the option to periodically retrieve the bridge every few years to check all of the parts and easily perform any necessary scaling and debridement. I would be very interested to hear what my colleagues say about my approach to crown cementation.

Why is it that no form of “loctite” has ever been introduced for use with implant screws!?

Marks, I have no problems with screws, I don't use screws the systems that I have used for many years are True Morse engagement 1.5 degrees, and I cement all my crowns and bridges with permanent cement. Trouble free and I can sleep at night without having to worry about screws coming loss.

The most frequent cause of abutment screw loosening is OCCLUSION. Check the occlusion in lateral, protrusive, CO and MI. You will find once the premature contacts, working and non-working interferences are eliminated from the implant crown( you need to use the 12 micron thick mylar articulating tape or shim stock) the loose screw will be eliminated. Also make a nocturnal occlusal guard to protect the implant from parafunctional habits. I do believe not permanently cementing the implant crowns are better than having to cut them off!

Jerome, The reasons that you mentioned are important factors in screws becoming loos. The main factor is thread and screw design including the base of the screw head and the internal portion of the abutments. We don't here that the screws in the car tires become loose, even thought they suffer from a lot of forces in the road. The main reason is that those screws are properly designed. In implant dentistry any Micky Mouse idea is applied to the screws. Give you one example, there is a company I reserve the name, that was having problems with screws becoming loss. Instead of fixing the screw design what they did is they made the screw out of gold so they could distort and stay in place. What they created was a nightmare, since now the screws started to fracture and the doctors had a hard time removing them. Wao but then they had a new source of income, " Screw Removing Instrument" . See the mistake keeps propagating, but Company income increases since they sale more instruments and more parts. Good Luck with loss screws.

Maxillary Anterior restoration success is occlusion dependent. Deep lower bites and lower anterior movement will stress maxillary restorations. This will not be the first concern of the restoring dentist and it is definitely not a believable fact for the patient to accept. LOOK AT BITE STABILITY AND GUIDENCE AND CONSIDER THAT LOWER ANTERIORS ARE NOT GOING TO STAY FIXED.

Some abutments have "captured" screws (Ankylos?) that are retained in the abutment and can't be screwed back out of the abutment. The screw comes out with the abutment. You must pull up on the abutment while unscrewing. Sounds like the threads have stripped though.

Best answer....don’t use implants with screws! Why are they still being used???