TissueDB/Simulators/Cleft Palate Repair Simulator (Nicholas)

The Cleft Palate Repair Simulator (Nicholas) is a low-cost trainer for infant cleft palate repair, built as a 3D-printed skeletal base that carries a disposable silicone soft-tissue cartridge.^[1] The paper is accompanied by a Supplementary Appendix holding the research-ethics approval, the trainee instruction manual, and the knowledge and confidence questionnaires.^[2] Trainees use it to practise the vomerine mucosal flap and intra-velar veloplasty, and the source notes it also accommodates the Furlow opposing Z-palatoplasty.

Source — every material, build step, and cost on this page is drawn from Nicholas et al. 2022 unless a cell notes otherwise. The £64.30 total is the paper’s Table 1: £38 for the skeletal base including the lower jaw and upper head, plus £26.30 for the cartridge.

Development and ethics approval — The simulator was developed at Brunel University London. The Research Ethics Committee of its College of Engineering, Design and Physical Sciences issued a conditional letter of approval on 17 December 2018 for the project "Cleft Palate Training Simulator", applicant Rute Pereira Crespo Fiadeiro, reference 13732-LR-Dec/2018-15492-3, covering observation and filming of participants working on the simulator only. The pilot study reported in the 2022 paper followed.

Images — Figures 1–6 of Nicholas et al. 2022 are published under "© 2022 British Association of Plastic, Reconstructive and Aesthetic Surgeons (BAPRAS), published by Elsevier Ltd. All rights reserved." This all-rights-reserved licence does not permit redistribution on Appropedia, so no hero image is embedded on this page. Readers may consult the figures at the source DOI 10.1016/j.bjps.2022.06.079.

The source describes the construction workflow in the Methods of Nicholas et al. (2022). The institutional manufacturing steps:

1. Step 1: Take a fine-cut CT scan of a formaldehyde-preserved pathology specimen. The source used a preserved specimen because living-infant CT scans were too widely spaced to give the needed skeletal detail, owing to radiation-exposure limits.
2. Step 2: 3D-print the skeletal base in VeroWhite from the CT geometry. Print orientation, layer height, and print time are not stated in source.
3. Step 3: Mold the skeletal base in hard plastic from the 3D print. The paper states that the reusable parts "can be manufactured locally with the open access stl. file of the designs" but gives no address for it. No public location was found: the article full text carries no data-availability statement, repository or URL; the Supplementary Appendix holds only the ethics approval, the instruction manual and two questionnaires; and a web search returned no public copy. The only route the source offers is a request to the corresponding author of Nicholas et al. (2022).
4. Step 4: Wax-model each soft-tissue layer (hard-palate mucoperiosteum, soft-palate oral mucosa, soft-palate nasal mucosa, and muscle) onto the skeletal base.
5. Step 5: 3D surface-scan each waxed layer to capture its geometry.
6. Step 6: Generate a mold for each layer from its scan. Mold material is not stated in source.
7. Step 7: Cast each layer in silicone, varying the shore hardness to mimic each tissue. Specific shore-hardness values are not stated in source.
8. Step 8: Build up the cast layers in sequence to form the disposable soft-tissue cartridge.
9. Step 9: Seat the cartridge into the base, which carries the adjustable mandibular component used to grade oral access.

The manual given to the trainees is published as Appendix 2 of the paper's Supplementary Appendix, under the title "Cleft Palate Training Simulator — Step-by-Step Guide". It runs to 22 photographed steps performed on the simulator itself. The phases below follow that guide. Steps 13 and 14 of the source repeat steps 9 and 10 word for word; they are given once here. The source's photographs are under an all-rights-reserved licence and are not reproduced on this page — see the licence note in General Information.

Two cautions are the source's own. The greater palatine artery is the pedicle to the lateral-release flap and lies medial to the posterior part of that incision. The nasal mucosa is very thin, and the guide warns against making holes in it while lifting the muscle off it.

Step 1: Mark and incise the cleft margin Mark the incision line along the margin of the cleft and incise until you are touching the bone. The source notes that a beaver blade is helpful. Mark the vomer flap at the same time.

Step 2: Incise the vomer flap down to bone Carry the vomer-flap incision down to the bone of the vomer.

Step 3: Lift the mucoperiosteal flap off the bone Raise the mucoperiosteal flap clear of the underlying bone.

Step 4: Lift the mucoperiosteum off the palatal shelf for about 3 mm Continue lifting the mucoperiosteum off the bone of the palatal shelf for approximately 3 mm.

Step 5: Suture the vomer flap under the oral mucosa Place horizontal mattress sutures so the vomer flap sits beneath the oral mucosa. Enter through the oral mucosa, come out through the bone-side surface of the vomer flap, pass back through the flap to create the horizontal mattress, and come back out through the oral mucosa.

Step 6: Place 3–4 horizontal mattress sutures with the knots on the oral layer Place three to four horizontal mattress sutures so the knots sit on the oral layer. Each suture passes through the oral layer, through the raw side of the flap to its mucosal surface, and back out of the oral mucosa. When tightened, the vomer flap should sit under the oral mucosa.

Step 1: Mark the lateral releases Mark the lateral releases adjacent to but not within the gingiva, continuing slightly posterior to the alveolus. The greater palatine artery is the pedicle to the flap and lies medial to the posterior part of the incision.

Step 2: Incise to bone and release midline tension Incise down to bone and lift the mucoperiosteum off it to release the tension from the midline.

Step 1: Incise along the cleft margins between oral and nasal mucosa Incise along the margins of the cleft, between the oral and the nasal mucosa. The source notes that in a real cleft the surgeon sees a colour difference between the two, which this simulator does not reproduce.

Step 2: Incise the cleft margins to approximately 2 mm on both sides Take the margin incision to approximately 2 mm on each side.

Step 3: Suture the nasal mucosa closed with the knots on the deep surface Close the nasal mucosa so the knots sit on the deep surface — at the nasal floor rather than within the cleft palate.

Step 1: Separate the soft-palate muscle from the mucosa above and below The muscle in the soft palate must be separated from the oral mucosa overlying it and the nasal mucosa beneath it. Incise the muscle gently until the nasal mucosa comes into view.

Step 2: Lift the muscle off the nasal mucosa, leaving a cuff Lift the muscles off the nasal mucosa without making holes in it, and separate the muscle from the oral mucosa. Leave a cuff of muscle on the nasal mucosa to stop the thin mucosa tearing.

Step 3: Free the muscles while keeping them attached laterally The muscles should remain attached laterally, but free them enough that they can be pushed to the back of the palate.

Step 4: Suture the muscles and close the oral layer Suture the muscles together with horizontal mattress sutures so they sit at the back of the palate, then close the oral mucosa with either interrupted or mattress sutures.