Mid-Treatment MARPE, a Bolton Discrepancy, and the Prepless Hybrid That Saved a Virgin Tooth
- 6 days ago
- 4 min read
This patient had been mine for years. She had four daughters. Beautiful teeth. Almost no existing dentistry. The plan was straightforward: Invisalign to upright the axial inclinations, then a few veneers to close the size discrepancy and open up those buccal corridors. I started the Invisalign myself.
And then I started learning more about airway.
Halfway through her aligners, I knew something wasn’t right. Her teeth were uprighting. She was looking better. But I kept looking at her arch and thinking — she’s still so narrow. And then she mentioned, almost in passing, that she couldn’t breathe through her nose. I pulled her CBCT. Deviated septum. A maxilla that wasn’t sitting over her mandible the way the Penn research says it should — that five-millimeter difference that tells you the upper arch is actually doing its job.
That was the moment I had to tell a longtime patient, mid-treatment and mid-fee, that there was a better way.
I called Dr. Katie Bullwinkel. She’s an orthodontist here in Charleston who has trained extensively in airway — the MARPE Symposium, Victor and Tracy’s course, and others — and she’s the person I trust with cases like this. I handed Kim over to her, and Katie took it from there.
The Numbers
Once Katie finished the expansion and we completed the Invisalign, the measurement told the full story. A maxillary Bolton discrepancy of 2.2 millimeters. Kim’s centrals were 7.5mm — they wanted to be closer to 8. Her laterals were 5mm — they wanted to be closer to 6. And because her teeth were already in the right anteroposterior position, we couldn’t get that width by coming forward. It had to come from skeletal expansion. That’s what MARPE gave us.
Without it, I would have been stacking porcelain onto teeth that had nowhere to go.
The Restorative Dilemma
The plan was as conservative as I could make it: replace the existing crown on #8, near-prepless veneers on #7, #9, and #10, and direct composite on #6 and #11 to bring out the canine mesials without touching enamel.
Then we hit the problem that anyone doing prepless work in a closed diastema space will recognize. To give the lateral a facial path of insertion, I would have had to chop off the mesial half of a virgin tooth. That improves nothing. It takes the risk profile in exactly the wrong direction.
Here’s the pearl: give the veneer a facial path of insertion that stops at the natural tooth contour, then backfill the lingual-to-facial gap with a Class III composite. The porcelain stays untouched. The tooth stays untouched. If anything ever needs attention at that interface, you replace the composite — not the veneer, not the tooth. The risk lives where you can manage it.
The sequencing matters too. Seat the veneer first. Do the composite while you still have room to run a disc and a diamond strip. Then seat the crown. Do it in the wrong order and you’ve created a micro-space you built yourself.
The Tissue Conversation
Vertical position came from #9 because it was prepless — that anchor point drove everything else. Soft-tissue crown lengthening on #7, #8, and #10. A scallop adjustment on #9 to compensate for the axial inclination without raising the height. And the papilla between #8 and #9 was never going to be ideal. That architecture wasn’t coming back. What I could control was the interproximal contact — long enough to close the black triangle without pinching the tissue that was there. Heavy-gauge blue rubber dam pulled the papilla down far enough to bond cleanly.
Zero moisture. Zero bleeding. That’s what isolation gives you that nothing else does.
What This Case Is Really About
Katie and I have talked about how common this situation is — a patient you’ve had for years, acquired before you were asking the right questions, now sitting in a treatment plan that was as good as you knew how to make it at the time. The airway questions weren’t in my new patient flow then. Kim never told me she couldn’t breathe. I wasn’t asking.
The self-limiting factor in those conversations is always us. Our discomfort with redirecting a case we already started. Our worry about what it costs the patient, financially and emotionally. But the job is to tell them. Tell them what you know now. Let them decide. Kim chose to do it. And she finished with a wide, full arch, healthy tissue, no tooth structure removed, and an airway that actually functions.
The painful part is admitting you would have done it differently if you had known. The generous part is doing it differently now.
What We Covered in This Discussion
How to recognize the clinical signs that Invisalign alone won’t solve the underlying problem
The skeletal measurements that drove the MARPE decision: the Penn five-millimeter maxilla-to-mandible standard, and how to apply it at the CBCT
How Dr. Bullwinkel approaches the no-diastema MARPE protocol and why slower expansion produces better tooth angulation and tissue outcomes
Bolton discrepancy analysis: how to determine whether the width you need comes from skeletal expansion or restorative addition
The prepless-veneer-plus-composite hybrid: path of insertion logic, delivery sequence, and why the risk lives where it should
Soft-tissue crown lengthening, papilla management, and heavy-gauge rubber dam isolation for bonding in a compromised tissue environment
Axial inclination and space distribution: why two-thirds of the space belongs on the mesial of the lateral, and what happens when orthodontists don’t know that
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