Management of Excess Gingival Display Using Tunnel Technique With 3D Designed PEEK Shell: A Case Series (PEEK)

The aim of the current study is to evaluate the use of a PEEK shell placed in the anterior maxilla placed by tunnel technique in decreasing the gingival display

Study Overview

• Status: Completed
• Conditions: Excessive Gingival Display
• Intervention / Treatment: Other: tunnel technique with a 3D printed PEEK shell to fill the skeletal subnasal depression

Detailed Description

While lip repositioning has been established as a treatment modality to address excess gum display (EGD) , an often overlooked contributing factor is the lack of lip support. This is often caused by the architecture of the maxilla at the subnasal area. Maxillary overgrowth may give rise to a subnasal skeletal depression producing decreased lip support and marked upper lip retraction during a smile.

Restricting muscle pull by lip repositioning surgery as a treatment option limits muscle movement, however it does not address lip support. In 2018 an alternative intervention was later proposed in a case report study . The technique involves raising a full thickness flap and applying PMMA (polymethyl methacrylate) cement to fill the subnasal depression and limit the upper lip movement. Since its introduction, a limited number of studies have attempted to investigate the technique, however there are not enough studies to support the outcome or the stability of the technique. The aim of the current study is to evaluate the use of a tunnel technique with a 3D printed PEEK (Polyetherether ketone) shell to fill the skeletal subnasal depression

• Study Type: Interventional
• Enrollment (Actual): 10
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Egypt
  • Cairo, Egypt, 11835
    • Farah Mamdouh

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Patients with excess gingival display 2.5mm or more
• Patients with an exaggerated subnasal concavity
• Decreased/normal value of SNA ( angle between sella, nation, A point) in cephalometric measurement
• Decreased/normal cephalometric measurement of A to N-perpendicular (perpendicular from N on FHP)
• Decreased/normal value in cephalometric measurement of the convexity at point A (linear measurement from point A to facial plane)
• Decreased/normal value of Ricketts Esthetic plane in cephalometric measurement
• Decreased/normal value of Holdaway H-angle in cephalometric measurement
• Nasolabial angle range from 100° to 120°
• Patients 20-60 years old
• Medically free
• Compliant patient that agrees to the follow up period

Exclusion Criteria:

• Pregnant and lactating females
• Smokers
• Diabetics
• Patients with parafunctional habits that may affect the outcome of the procedure
• Medically compromised patients

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm

Intervention / Treatment

Experimental: PEEK shell in the anterior maxilla inserted by tunnel technique; use of a minimally invasive tunnel technique to fill the skeletal subnasal depression with a PEEK shell in patients with an exaggerated subnasal depression associated with lack of lip support and excessive lip translation

Other: tunnel technique with a 3D printed PEEK shell to fill the skeletal subnasal depression; The area will be anesthetized using infiltration technique with 1.5ml of anesthetic solution containing Articaine Hydrochloride 68 mg/1.7 ml with Adrenaline 0.017 mg/1.7 ml Two bilateral full thickness vertical incisions will be created using a #15 blade. One on each side of the frenum A subperiosteal tunnel connecting the two vertical incisions will be created using a periosteal elevator/tunneling knife until the complete communication between the two ends is established The custom made PEEK framework will be inserted from the incision on one side and eased through until it sits in the subnasal concavity. Once fitted in place the shell will be fixed in place using two mini screws bilaterally, one on each side. The two vertical incisions will be closed by interrupted sutures 6-0 Polyglycolic acid suture material

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Gingival display	measured using a periodontal probe in millimeters	Day 0 - Month 3 - Month 6

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
lip translation	measured using a periodontal probe in millimeters	Day 0 - Month 3 - Month 6
profile angle	lateral cephalometric xray	Day 0 - Month 6
lip length	measured using a periodontal probe in millimeters	Day 0 - Month 3 - Month 6
patient satisfaction	measured by a binary Questionnaire ( yes or no)	Day 7
Post operative pain	Measured by the visual analogue scale ( 0 no pain, 10 worst pain)	Day 7
blinded esthetic assessment	measured by a binary scale (yes or no)	Month 3- Month 6

Collaborators and Investigators

• Sponsor: Cairo University

Publications and helpful links

General Publications

• Dym H, Pierre R 2nd. Diagnosis and Treatment Approaches to a "Gummy Smile". Dent Clin North Am. 2020 Apr;64(2):341-349. doi: 10.1016/j.cden.2019.12.003. Epub 2020 Jan 24.
• El-Bokle, Dalia & Ghany, Amany. (2022). A sequential diagnostic scheme for excessive gingival display (Gummy Smile). AJO-DO Clinical Companion. 2. 10.1016/j.xaor.2022.05.003
• Impellizzeri A, Palmigiani R, Horodynski M, D'alfonso T, Polimeni A, De Stefano A, Galluccio G. Is There a Correlation between Gingival Display and Incisal Inclination in a Gummy Smile? Study on Cephalometric Parameters. Healthcare (Basel). 2023 Jan 25;11(3):344. doi: 10.3390/healthcare11030344.
• Monaco A, Streni O, Marci MC, Marzo G, Gatto R, Giannoni M. Gummy smile: clinical parameters useful for diagnosis and therapeutical approach. J Clin Pediatr Dent. 2004 Fall;29(1):19-25. doi: 10.17796/jcpd.29.1.y01l3r4m06q3k2x0.
• Toth, J. M. (2012). Biocompatibility of Polyaryletheretherketone Polymers. PEEK Biomaterials Handbook, 81-92. doi:10.1016/b978-1-4377-4463-7.10007-7
• Freitas de Andrade P, Meza-Mauricio J, Kern R, Faveri M. Labial Repositioning Using Print Manufactured Polymethylmethacrylate- (PMMA-) Based Cement for Gummy Smile. Case Rep Dent. 2021 Dec 21;2021:7607522. doi: 10.1155/2021/7607522. eCollection 2021.
• ASSENZA, B. & Carinci, Francesco & CRISTINZI, A. & Sinjari, Bruna & Murmura, Giovanna & Scarano, Antonio. (2011). A COSMETIC TECHNIQUE CALLED LIP REPOSITIONING IN PATIENT OF EXCESSIVE GINGIVAL DISPLAY. European Journal of Inflammation. 9. 115-119.
• Saleem R, Kukreja BJ, Goyal M, Kumar M. Treating short upper lip with "Unified lip repositioning" technique: Two case reports. J Indian Soc Periodontol. 2022 Jan-Feb;26(1):89-93. doi: 10.4103/jisp.jisp_90_20. Epub 2022 Jan 1.
• Labial repositioning using polymethylmethracylate (PMMA)-based cement for esthetic smile rehabilitation-A case report Toni Arcuri a, Maykson Feitosa Pereira da Costa b, Iury Machado Ribeiroa, Byron Daia Barreto Júnior b, João Paulo Lyra eSilvac,∗ a Department of Dentistry, Paulista University, UNIP, Brasília, Brazil b Private Office in Brasilia, Brazil c Department of Dentistry, Universitary Center Euro Americano, UNIEURO, Brasília, Brazil
• Brizuela M, Ines D. Excessive Gingival Display. 2023 Mar 19. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2026 Jan-. Available from http://www.ncbi.nlm.nih.gov/books/NBK470437/

Study record dates

Study Major Dates

• Study Start (Actual): November 8, 2023
• Primary Completion (Actual): January 7, 2026
• Study Completion (Actual): January 7, 2026

Study Registration Dates

• First Submitted: August 17, 2023
• First Submitted That Met QC Criteria: August 28, 2023
• First Posted (Actual): August 30, 2023

Study Record Updates

• Last Update Posted (Actual): March 23, 2026
• Last Update Submitted That Met QC Criteria: March 19, 2026
• Last Verified: March 1, 2026

More Information

Terms related to this study

• Other Study ID Numbers: 21623 (City of Hope Medical Center)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Sharing Time Frame: 2025
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; CSR

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No