The Anatomy of the Cleft, What Is Actually Interrupted
In a , what exactly is the gap, and what happens to the and the ?
💡 A is a gap plus ; the muscles do not just stop, they insert in the wrong place and pull the wrong way.
Prerequisite check
- The is a , a continuous ring of muscle around the mouth that crosses the to seal the lips.
- The is paired; the left and right fibers join in the to form a sling across the soft .
What you will learn
Goal: Explain that a is a gap where failed to join, and that the muscles insert abnormally and pull the wrong way (displaced in the lip, displaced in the ).
- A is a gap left where tissues that should have joined during development did not (a failure of ).
- In a lip the ring is interrupted and its fibers run up the cleft margins instead of crossing the .
- In a the fails to form its sling and inserts onto the back of the .
- There is an open , a connection between the mouth and the nose, along the gap.
Model: Mateo's findings, and where the muscles go in a cleft
The team examines Baby Mateo (a composite teaching case, not a real patient). On the left side, his upper lip is split all the way up into the nostril. The split continues back through his gum ridge (the ) and through the whole roof of his mouth, and soft , on the left side. The right side is intact. There is an open connection between his mouth and nose along the gap. The rest of his is normal, with no other birth defects noted.
Now look at the muscles. In the lip, the ring is interrupted at the . The fibers do not just end; instead of crossing the they turn and insert in the wrong place, running up along the edges of the cleft toward the base of the nostril and the base of the . Because the muscle pulls along the gap instead of across it, the lip is pulled apart and the nose is distorted. In the , the does not form its normal side-to-side sling; the fibers run the wrong way (front to back) and insert abnormally onto the back edge of the bony . Imaging studies confirm the levator is abnormal in thickness and in cleft palate, with the most disturbed in children who still cannot seal the .
Explore (work the model before reading on)
- Trace Mateo's gap. Which structures does it pass through, and on which side?
- Is Mateo's right side affected?
- When the reaches the , does it cross the as usual, or turn and insert somewhere else?
- Recall the Lesson 2 rule. Explain why an interrupted, misdirected cannot seal the lip.
- Predict: if a surgeon only closed the skin over the gap but left the muscles pointing the wrong way, would the lip and work normally? Why or why not?
Guided notes
What a cleft is
- The developmental joining of separate blocks is called ____.
- Along the gap there is an open ____ communication, a connection between mouth and nose.
The displaced muscles
- In the lip, the ring is interrupted and its fibers run up the margins instead of crossing the ____.
- In the , the levator fails to form its sling and inserts abnormally onto the back of the ____ palate.
The big idea
- A is a gap PLUS ____ muscle, which is why a good repair is not just closing skin.
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.
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: Make a two-column "Normal vs Mateo" chart for the orbicularis oris and the levator veli palatini. For each muscle, write (1) the normal direction and continuity from Lesson 2 and (2) what happens to it in a cleft. End with one sentence: why must repair fix the muscle, not just the skin?
- Wrote my Claim, Evidence, and Reasoning exit ticket.
Exit ticket (Claim, Evidence, Reasoning)
- Claim: A is not only a gap; it is a gap plus ____.
- Evidence: Describe what happens to the and the in a .
- Reasoning: Explain why closing only the skin would not restore normal lip seal or lift.
| 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 "Make a two-column "Normal vs Mateo" chart for the orbicularis oris and the levator veli palatini. For each muscle, write (1) the normal direction and continuity from Lesson 2 and (2) what happens to it in a cleft. End with one sentence: why must repair fix the muscle, not just the skin?".
- 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 know exactly what is interrupted in Mateo and that the muscles are displaced. But we keep describing his in long sentences. How do surgeons describe a cleft precisely and briefly enough that any team in the world knows exactly what they mean? We chase that next time.