Why the Repaired Midface Grows Backward
Why does a repaired grow poorly forward, and what does that do to the shape of Mateo's face and the way his teeth meet?
💡 Two forces, the 's own poor forward growth plus the restraining scar, leave a flat midface and an underbite.
Prerequisite check
- An packs spongy , classically from the , into the cleaned-out bony gap so the arch becomes continuous.
- It is a secondary procedure done in the , timed to the canine that is about to erupt.
What you will learn
Goal: Explain how a repaired grows poorly forward, why scar adds a restraining effect, and how this produces a flat midface and a Class III (underbite) tendency.
- The is the upper jaw and the bone of the midface, the region under the eyes and around the upper lip.
- Two forces hold the midface back: an intrinsic tendency to grow poorly forward, plus a restraining scar from surgery.
- The result is a flat, set-back midface, called or .
- When the upper jaw is set back but the lower jaw grows normally, the lower teeth close in front of the upper teeth, a .
Model: Two forces holding the midface back, and evidence the surgery interacts with growth
The is the upper jaw and the bone of the midface, the region under the eyes and around the upper lip. In a child born with a , two forces together hold this midface back as the child grows: an intrinsic tendency, where the cleft maxilla simply grows poorly forward on its own, and a scar effect, where the scar left on the roof of the mouth by surgery adds a restraining, tethering pull on forward growth. The result is a flat, set-back midface, called or .
The scar effect is not just a theory. A multicenter functional study of children with lip and compared palate-repair techniques. A pushback (Veau-Wardill-Killner) was associated with MORE maxillary deficiency, a more constricted, deficient upper jaw. A two-stage protocol with a Sommerlad veloplasty had LESS negative impact on maxillary growth. Separately, patients who screened positive for sleep-disordered breathing were more likely to have a Class III bite with maxillary retrusion.
So the more a repair scars or shortens the , the more the midface tends to be held back, and a set-back midface and a narrowed airway tend to travel together. A reminder from last lesson: the alveolar bone graft did not significantly change whether a patient later needed major jaw-advancement surgery. The problem is a separate consequence the team must track and plan to correct on its own.
Explore (work the model before reading on)
- Name the two forces that together hold the midface back.
- Which -repair technique was associated with MORE maxillary deficiency, and which with less?
- If the upper jaw fails to grow forward while the lower jaw grows normally, predict how the front teeth line up when Mateo bites down. Which jaw ends up in front?
- Is the set-back midface caused only by the itself, or does the surgery play a part too? Support your answer with one finding.
- A set-back was linked to a positive sleep screen. Predict why a midface that has grown backward might also make breathing during sleep harder.
Guided notes
The two forces
- The upper jaw and bone of the midface is the ____.
- The palatal ____ from surgery restrains forward growth, adding to the intrinsic tendency.
Surgery interacts with growth
- A pushback was associated with ____ (more) maxillary deficiency; a two-stage Sommerlad protocol had ____ (less) negative impact.
The bite result
- A set-back upper jaw with a normal lower jaw gives an underbite, called a ____ .
- Patients with this set-back pattern were also more likely to screen positive for ____ -disordered breathing.
Reading the Research
- Skim the title and abstract first to get the gist.
- Circle the one sentence that states the main claim.
- Box the evidence the authors give for that claim.
- Mark one sentence that confuses you, and move on.
Vocabulary (the same words your classes use)
Vetted readings for this lesson
- Dissaux et al. 2016, Evaluation of 5-Year-Old Children With Complete CLP, Part 2 (J Craniomaxillofac Surg)
- Fisher et al. 2024, Risk Assessment of Sleep-Disordered Breathing in Cleft Lip and/or Palate (Cleft Palate Craniofac J)
- Powell et al. 2022, Does Early Secondary ABG Influence Need for Maxillary Advancement (Cleft Palate Craniofac J)
Track your progress today
Check these off as you work through the lesson, then submit. This tells Mr. Mendoza how you're doing so he can help the class. It does not replace turning in your producible.
Use the code Mr. Mendoza gave you, not your name. Saved on this device.
- Read the Model and answered the Explore questions.
- Filled in the guided notes in my own words.
- Defined the new vocabulary with an example.
- Built the producible: Write one line in Mateo's growth chart at age 12, in three short sentences a parent could read: name what you are watching for in his midface and bite using today's terms, explain in plain words why his upper jaw tends to sit back (name the two forces), and note that this is something the team will plan to correct later, not a sign the earlier surgeries failed.
- Wrote my Claim, Evidence, and Reasoning exit ticket.
Exit ticket (Claim, Evidence, Reasoning)
- Claim: Mateo's repaired is likely to leave him with a flat midface and an underbite as he grows.
- Evidence: Cite the two forces holding the back, and one finding linking repair technique or the set-back midface to an outcome.
- Reasoning: Explain why a that grows too little forward causes the lower teeth to close in front of the upper teeth.
| Criterion | Proficient | Developing | Beginning |
|---|---|---|---|
| Complete | Every required part of the artifact is present and filled in. | Most parts are present, but one is missing or left blank. | Several parts are missing. |
| Accurate | The science and data are correct and match the evidence. | Mostly correct, with a small factual slip. | Key science or data is wrong. |
| Scientific reasoning (CER) | States a claim, backs it with specific evidence, and explains the reasoning. | Has a claim and evidence, but the reasoning is thin or missing. | Gives an answer with no evidence or reasoning. |
| Professional communication | Clear, organized, and labeled the way a clinician or scientist would write it. | Readable but disorganized or missing labels. | Hard to follow. |
| Submitted | Turned in the right way (Schoology for routine work) and confirmed. | Turned in, but in the wrong place or unconfirmed. | Not turned in. |
- CompleteProficient: Nothing is left blank: the model fills every part of "Write one line in Mateo's growth chart at age 12, in three short sentences a parent could read: name what you are watching for in his midface and bite using today's terms, explain in plain words why his upper jaw tends to sit back (name the two forces), and note that this is something the team will plan to correct later, not a sign the earlier surgeries failed.".
- AccurateProficient: Every number and claim matches the case evidence.
- Scientific reasoning (CER)Proficient: It names a claim, cites the specific evidence, and explains the reasoning, not just the answer.
- Professional communicationProficient: It is organized and labeled like a real chart note.
- SubmittedProficient: It would be turned in on Schoology and confirmed.
Where this leads: careers
What's next: We found out why Mateo's midface grows backward and ends up flat, leaving an underbite as a teenager. We can name the problem, but we have not fixed it: the lip, , and gum graft are all done, yet his upper jaw still sits too far back. How do we correct the bite and midface later? We chase that next time.