Resin bonded bridges, often known as Maryland bridges, have had a bad reputation over the years. The are very challenging to do well and reach your esthetic and functional goals and lastly feel confident their longevity. With this said, they do have some clinical advantages. One of these is minimal to no prep in the appropriate clinical situations. Another advantage is the ability to place a fixed replacement for missing anterior teeth as compared to something removable. Another advantage is they can be a very nice transitional restoration for patients whose age precludes them from implant placement until growth is completed.
Recently I had just the perfect case for a resin bonded bridge. The patient is a young women in her teens. She is not an ideal implant candidate due to her age and needing to verify that growth is complete, as well as being a type 1 diabetic. We wanted a solution that would be minimally invasive to the natural teeth, replace her Hawley retainer with pontics for congenitally missing laterals, and leave options open for future restorative options. So, what do you need to think about to have these restorations be successful.
Preparations
First, minimal to no occlusal load on the pontic is ideal. So patients with very shallow overbites or a large amount of overjet make better candidates. The ability to avoid the pontics in all lateral excursions, including crossover. Solid enamel surfaces to bond to and the ability to have appropriate connector size between the pontic and the wing. Lastly, resin bonded bridges have a much higher success rate and longevity when they are only bonded with one wing. 
When I first heard this it sounded counter-intuitive until you think about the physics. When you use only one wing the pontic can move with the abutment under load. With two wings, especially around a curve, the forces are directed differently and the movement of one tooth causes the bond to be flexed causing a bond failure over time.
Since using these criteria, and fabricating resin bonded bridges with only one wing I have come to appreciate their place int he appropriate clinical situations. In this case we placed e.max resin bonded bridges with wings on the central incisors.
Do you have a picture of the completed restoration from the incisal view?
I don’t unfortunately, but I will try and get one at the followup.
Hi Lee, in Europe, we have been teaching one-wing only Maryland for 10-15 years after a number of studies showed two wings tho providing rigidity, does not allow for natural tooth movement in function. A two-wing design will usually debond at one end, leaving a hidden surface where palatal/lingual surface demineralisation and decay starts. As you say, the concept sounds counter-productive, that is until you start to consider the physics and stresses involved. Regards, Julian
Hi Lee;great post thank you for sharing with us!! How do you prepare the surfaces on the lingual for the e-max wing to make space and temporise it?I heard that e-max Marylands can break/chip? Perhaps you could do a webinar on this technique? Would be v useful!!!
Best wishes,
Sharon
The lingual prep is just like a minimal prep labial veneer. Keep everything in enamel if possible so I did a .3mm reduction champfer at the lingual and across the lingual up to 2mm from the incisal edge and wrapped into the interproximal contact. this is an off label use of e/max not due to a risk of the wing but the connector size. You need ample room to do an adequate connector, at least 2mm by 2mm or more. So this would not work with a tight occlusion or deep bite case.
Hi Lee,
Great topic. Great result. I bet the patient was happy.
I, too, would love to see a photo of the linguals of the centrals prep’d and restored.
Did you provisionalize?
Do you think something similar could be made from milled composite ie from a Cerec?
Just curious as usual!
CARL B. FITZSIMMONS
I did not provisionalize, we kept the patient in her upper Hawley retainer. The preps are totally in enamel so she had no sensitivity. There is a photo of the prepped linguals in the post already and I will try and get a post op when the patient is back in for everyone.
Thank you Lee!! If the patient did not have a retainer would you provisionalise? Thank you !!!
Sharon,
Most likely not, as it is very difficult to do. If the patient wanted the laterals replaced it would be a good time for an essex retainer with the two teeth in it.
Great topic Lee. I was wondering what criteria you use to determine which teeth to use as abutments? I assume that in this case you used the centrals to avoid the lingual surfaces of the maxillary cuspids during lateral excursion.
However, which teeth would you use as abutments for a single winged bonded bridge to restore congenitally missing teeth #23 and #26? Would teeth #22 and #27 be your preference?
Thank you.
Brent,
You are correct that on the maxillary I opted for the central due to excursive forces on the canine, but also a larger lingual surface area to prep to. On the lower I would assess the lingual surfaces and if one tooth will have a better bonded interface this can be a deciding factor. Also you have to look at the interproximal connector. There are some minimum size requirements and this can be easier with a central abutment versus a canine depending on tooth shape and size.
dentaltown also has a nice thread on this topic. Similar idea slightly different take though. Definitely agree one wing better. Thanks for sharing!
http://www.towniecentral.com/MessageBoard/thread.aspx?a=11&s=2&f=101&t=171758&g=1&st=missing%20laterals..not%20enough%20room%20for%20implants..help!
and here
http://www.towniecentral.com/MessageBoard/thread.aspx?s=2&f=101&t=195317&v=1
Maybe a 2 way bond is okay for my kid. I already consulted my studio city dentist and she said that it is safe for kids ages 12 and below. Even I am interested. And after that a dental veneer would perfectly suit a new 2 bonded bridge.
What do you bond it with ?
i have an adult patient with missing 7,10., 6&11 erupted into the 7,10 position. retained C,H which have started to fail which prompted the ortho to open the bite and correct alignment. ortho completed with 6,11 in the lateral position. could a single wing maryland work replacing these canines (6,11), abutment on 7,10. if i keep her out of canine guidance (keep the occlusion off the pontic canine). pt may not want the implant even thought this would be the best option.
If the patient has a shallow bite with very little overbite, and you can keep all occlusion off the pontics this might work. I’d also only consider this is the patient is very low functional risk with no evidence of parafunction. The challenge of course will be if the premolars are situated on their buccal cusp to take the guidance. I also always advise my patients with these that they need to be very careful what they bite into with their front teeth.
i have an adult patient with missing 7,10., 6&11 erupted into the 7,10 position. retained C,H which have started to fail which prompted the ortho to open the bite and correct alignment. ortho completed with 6,11 in the lateral position. could a single wing maryland work replacing these canines (6,11), abutment on 7,10. if i keep her out of canine guidance (keep the occlusion off the pontic canine). pt may not want the implant even thought this would be the best option.
thank you for your response. pt has been staying away from her primary canines her entire life hoping to never lose them and she follows direction well. i am planning on putting the guidance on the premolar. i may even bond the guidance onto the premolar to ensure complete disarticulaltion in excursions. she would like to try this but i have told her that there is a chance it may not work and she does so at her own risk. what cement works best with these with full zirconium? btw, my good friend charlie bertot recommended i contact you.
thanks
ed