Gummy Smile of Altered Passive Eruption Type 1BNCT07891598
Accuracy of Stackable Double Periodontal Guide in Esthetic Crown Lengthening
A study testing Stackable double digital periodontal guide and Conventional double digital periodontal guide in people with Gummy Smile of Altered Passive Eruption Type 1B, run by Ain Shams University.
Trial summary
The goal of this clinical trial is to find out if a new digital surgical guide helps dentists perform esthetic crown lengthening more accurately than the current digital guide in adults with a gummy smile caused by altered passive eruption. Read more about this study
- Who is it for?
- Ages 21 to 60 years
- Conditions the study is for
- Gummy Smile of Altered Passive Eruption Type 1B
- What is being tested?
- Stackable double digital periodontal guide and Conventional double digital periodontal guide
- Type of treatment
- Medical device
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 30 participants
- Where
- No sites listed yet
- Study dates
- Sep 2026to Sep 2028
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 21 to 60 years
- All sexes
- No healthy volunteers
- Adult
Who may be able to join
- Patients both genders aged from 21-40 years
- Patients complaining of Excessive gingival display (3mm or more gingival display at full smiling).
- Patients with Altered passive eruption (APE) type 1 B Coslet GJ et al., 1977).
- Patients have thick gingival phenotype (thickness of gingiva is ≥ 1 mm) (Greenberg J et al., 1976).
- Patients with healthy periodontium and no active periodontal disease, with good plaque control and stable gingival health prior to surgery.
Who cannot join
- Pregnant and lactating females.
- Poor oral hygiene.
- Smokers.
- Patients with systemic diseases which could influence the outcome of the therapy e.g. (Diabetic patients, bleeding disorders).
- Patients on immunosuppressive therapy or long-term corticosteroids.
- Patients on antiresorptive or antiangiogenic drugs (e.g., bisphosphonates, denosumab) that impair bone healing.
- Patients with vertical maxillary excess, dentoalveolar extrusion with deep bite, attrition, short lip length, hyperactive mobile upper lip.
Trial locations and contacts
No sites are listed yet. Contact the study team or a site near you to ask about taking part.
About this study
Official title: Accuracy of Stackable Double Periodontal Guide in Esthetic Crown Lengthening: (Randomized Controlled Clinical Trial)
The goal of this clinical trial is to find out if a new digital surgical guide helps dentists perform esthetic crown lengthening more accurately than the current digital guide in adults with a gummy smile caused by altered passive eruption. Esthetic crown lengthening is a procedure that reshapes the gums and the bone around the teeth to show more of the natural tooth. The main questions this study aims to answer are:
Does the new digital guide help dentists reshape the bone and gums more accurately? Does the new digital guide improve healing, the appearance of the gums, the time needed for surgery, and participants' satisfaction with the results?
Read more
Researchers will compare a new stackable digital guide with the current digital guide to see if the new design provides more accurate and predictable results.
Participants will:
- Be randomly assigned to have surgery using either the new digital guide or the current digital guide.
- Have dental examinations, digital mouth scans, and three-dimensional dental X-rays before surgery to plan their treatment.
- Have esthetic crown lengthening surgery using the assigned guide.
- Return for follow-up visits right after surgery and again about 6 weeks and 6 months later so researchers can check healing and compare the planned treatment with the final result.
- Answer questions about their satisfaction with the treatment and any pain medicine they used after surgery.
Read the detailed description
Esthetic crown lengthening is a surgical procedure used to improve the appearance of a "gummy smile" by exposing more of the natural tooth. One common cause of a gummy smile is altered passive eruption, a condition in which the gums cover more of the teeth than normal, making the teeth appear shorter. In some patients, treatment requires not only reshaping the gums but also removing a small amount of the supporting bone to create a healthy and stable relationship between the teeth, gums, and bone.
Digital technology has improved treatment planning for esthetic crown lengthening by allowing surgical guides to be designed using intraoral scans and cone-beam computed tomography (CBCT) images. These guides help the surgeon identify the planned gum and bone levels during surgery. However, currently available double digital periodontal guides may become less stable after the gum tissue is lifted during surgery because the guide is positioned on the soft tissue rather than directly on the bone. This may reduce the accuracy of bone reshaping.
This study will evaluate a newly designed stackable double digital periodontal guide that consists of two separate components. The first component is used to guide the gum incision, while the second component is attached after the gum flap is reflected and rests directly on the bone to guide bone reduction. This design is intended to improve guide stability during surgery and increase the accuracy of bone reshaping. The new guide will be compared with a conventional one-piece double digital periodontal guide.
Thirty adults with altered passive eruption type 1B who require esthetic crown lengthening will be enrolled and randomly assigned to one of the two treatment groups. All participants will receive the same standard preoperative assessment, including clinical examination, digital photographs, intraoral scanning, CBCT imaging, oral hygiene instructions, and nonsurgical periodontal therapy before surgery. Both groups will undergo esthetic crown lengthening using their assigned digital guide according to standardized surgical procedures.
Participants will be evaluated immediately after surgery and during follow-up visits at 6 weeks and 6 months. Digital intraoral scans and CBCT images will be used to compare the planned treatment with the actual surgical outcome. Additional assessments will include the stability of the gum margin, esthetic appearance of the gums, duration of surgery, postoperative pain medication use, and participant satisfaction with the treatment.
The findings of this study will provide evidence on whether the stackable digital guide offers improved surgical accuracy and more predictable clinical outcomes compared with the conventional digital guide. This information may help optimize digital workflows for esthetic crown lengthening and improve treatment planning for patients requiring correction of excessive gingival display.
- Being tested
- Stackable double digital periodontal guide, Conventional double digital periodontal guide
- Keywords
- esthetic crown lengthening, stackable double periodontal guide, double periodontal guide, digital periodontal guide
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Stackable double digital periodontal guideDevice
A custom-made, 3D-printed digital surgical guide used during esthetic crown lengthening. The guide consists of two detachable components: a gingivectomy guide for soft tissue incision and an ostectomy guide that is joined after flap reflection and positioned directly on the alveolar bone to guide bone reduction. The guide is designed using merged cone-beam computed tomography (CBCT) and intraoral scan data to improve the accuracy of bone reshaping.
Conventional double digital periodontal guideDevice
Also called double periodontal guide, digital periodontal guide, dual periodontal guide, dual digital periodontal guide
A custom-made, one-piece 3D-printed digital surgical guide used during esthetic crown lengthening. The guide directs both the gingivectomy and ostectomy based on the planned treatment using intraoral scan data .
After flap reflection, the guide is repositioned to guide bone reduction from the soft tissue level.
| Study group | Role | What they receive |
|---|---|---|
| Stackable double digital periodontal guide | Experimental | Participants undergo esthetic crown lengthening using a stackable double digital periodontal guide.
The guide consists of separate gingivectomy and ostectomy components that are assembled during surgery to guide bone reduction. Receives: Device: Stackable double digital periodontal guide |
| Conventional double digital periodontal guide | Active comparator | Participants undergo esthetic crown lengthening using a conventional one-piece double digital periodontal guide Receives: Device: Conventional double digital periodontal guide |
What is being measured
The primary outcome is the main question the study is designed to answer.
Difference in accuracy of both guides
Evaluation of the degree of matching of the post operative actual gingival zenith points with the virtual predicted presurgical plan.
Intraoral digital scanning for both groups will be obtained preoperative, immediately after surgery, and follow up appointments at 6 weeks and 6 months after surgery and exported in STL file format then it will be superimposed on the digitally designed diagnostic STL file to obtain statistical differences.The accuracy can be measured by comparing the planned surgery and the actual result of the surgery Linear measurement in millimeters.
Measured: 6 months
Secondary outcomes (6)
Bone level accuracy
The accuracy can be measured by comparing the planned surgical ostectomy level on the CBCT (cone beam computed tomography) and the actual result of the surgery by Linear measurement in millimeters.
Measured: 6 months
Gingival margin stability
The position of gingival margin in relation to a reference point will be evaluated with linear measurements in millimeters.
Measured: 6 Months
Pink Esthetic Score
The **Pink Esthetic Score evaluates seven variables of soft-tissue esthetics. 1)Mesial and distal papillae are scored as missing (0), incomplete (1), or complete (2).
2)Tissue contour is rated as unnatural (0), virtually natural (1), or natural (2). 3)Gingival level is scored according to the discrepancy from the reference tooth: >2 mm (0), 1-2 mm (1), or <1 mm (2).
4)Alveolar process, color, and texture are each scored (0),(1) and (2), depending on whether there is a (0)clear difference, (1)slight difference, or (2)no difference.
Higher scores indicate better esthetic outcomes with a maximum total score of 14.
Measured: 6 months
Surgical time
The time needed to complete each procedure will be calculated in minutes by using a stopwatch from the time of the first incision till removal of the guide.
Measured: time of the surgery
Patient satisfaction
Patient satisfaction was assessed using three direct questions previously applied in Kiyak et al.14:
- "Considering this was an elective operation, how likely would you be to recommend it to others?".
- "If you had to make the decision again, how likely would you be to undergo this surgery?".
- "Considering everything, how satisfied are you with the outcomes of your surgery?".
Responses were recorded using a seven-point Likert scale ranging from 1 (not at all likely or not satisfied) to 7 (very likely or very satisfied).
Measured: 2 weeks
analgesics
number of analgesics the patient took after the surgery till the day of sutures removal
Measured: 2 weeks
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted23 Oct 2026
- Study startSep 2026 (estimated)
- Primary completionSep 2028 (estimated)
- Study completionSep 2028 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Gummy Smile of Altered Passive Eruption Type 1BStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Single blind
- Who is masked
- Outcomes assessor
- Enrolment
- 30 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Ain Shams University
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Farah Mohamed, Ain Shams University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07891598
- Sponsor's protocol ID
- 1564
- Status last verified
- Oct 2026
- First submitted
- 25 Jul 2026
- Last updated
- 23 Oct 2026
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Undecided
Study at a glance
From the registry record, last updated by the sponsor on 23 Oct 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Accuracy of Stackable Double Periodontal Guide in Esthetic Crown Lengthening: (Randomized Controlled Clinical Trial)
- ClinicalTrials.gov ID
- NCT07891598
- Acronym / sponsor ID
- 1564
- Keywords
- esthetic crown lengthening, stackable double periodontal guide, double periodontal guide, digital periodontal guide
- Study type
- Interventional
- Recruitment status
- Not yet recruiting
- Enrolment
- 30 participants (estimated)
- Lead sponsor
- Ain Shams UniversityUniversity, hospital or other
- Study start
- Sep 2026 (estimated)
- Primary completion
- Sep 2028 (estimated)
- Study completion
- Sep 2028 (estimated)
- First posted
- 23 Oct 2026 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The goal of this clinical trial is to find out if a new digital surgical guide helps dentists perform esthetic crown lengthening more accurately than the current digital guide in adults with a gummy smile caused by altered passive eruption. Esthetic crown lengthening is a procedure that reshapes the gums and the bone around the teeth to show more of the natural tooth. The main questions this study aims to answer are:
Does the new digital guide help dentists reshape the bone and gums more accurately? Does the new digital guide improve healing, the appearance of the gums, the time needed for surgery, and participants' satisfaction with the results?
Researchers will compare a new stackable digital guide with the current digital guide to see if the new design provides more accurate and predictable results.
Participants will:
- Be randomly assigned to have surgery using either the new digital guide or the current digital guide.
- Have dental examinations, digital mouth scans, and three-dimensional dental X-rays before surgery to plan their treatment.
- Have esthetic crown lengthening surgery using the assigned guide.
- Return for follow-up visits right after surgery and again about 6 weeks and 6 months later so researchers can check healing and compare the planned treatment with the final result.
- Answer questions about their satisfaction with the treatment and any pain medicine they used after surgery.
Detailed description
Esthetic crown lengthening is a surgical procedure used to improve the appearance of a "gummy smile" by exposing more of the natural tooth. One common cause of a gummy smile is altered passive eruption, a condition in which the gums cover more of the teeth than normal, making the teeth appear shorter. In some patients, treatment requires not only reshaping the gums but also removing a small amount of the supporting bone to create a healthy and stable relationship between the teeth, gums, and bone.
Digital technology has improved treatment planning for esthetic crown lengthening by allowing surgical guides to be designed using intraoral scans and cone-beam computed tomography (CBCT) images. These guides help the surgeon identify the planned gum and bone levels during surgery. However, currently available double digital periodontal guides may become less stable after the gum tissue is lifted during surgery because the guide is positioned on the soft tissue rather than directly on the bone. This may reduce the accuracy of bone reshaping.
This study will evaluate a newly designed stackable double digital periodontal guide that consists of two separate components. The first component is used to guide the gum incision, while the second component is attached after the gum flap is reflected and rests directly on the bone to guide bone reduction. This design is intended to improve guide stability during surgery and increase the accuracy of bone reshaping. The new guide will be compared with a conventional one-piece double digital periodontal guide.
Thirty adults with altered passive eruption type 1B who require esthetic crown lengthening will be enrolled and randomly assigned to one of the two treatment groups. All participants will receive the same standard preoperative assessment, including clinical examination, digital photographs, intraoral scanning, CBCT imaging, oral hygiene instructions, and nonsurgical periodontal therapy before surgery. Both groups will undergo esthetic crown lengthening using their assigned digital guide according to standardized surgical procedures.
Participants will be evaluated immediately after surgery and during follow-up visits at 6 weeks and 6 months. Digital intraoral scans and CBCT images will be used to compare the planned treatment with the actual surgical outcome. Additional assessments will include the stability of the gum margin, esthetic appearance of the gums, duration of surgery, postoperative pain medication use, and participant satisfaction with the treatment.
The findings of this study will provide evidence on whether the stackable digital guide offers improved surgical accuracy and more predictable clinical outcomes compared with the conventional digital guide. This information may help optimize digital workflows for esthetic crown lengthening and improve treatment planning for patients requiring correction of excessive gingival display.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Single blind (outcomes assessor)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Stackable double digital periodontal guide | Experimental | Device: Stackable double digital periodontal guideParticipants undergo esthetic crown lengthening using a stackable double digital periodontal guide. The guide consists of separate gingivectomy and ostectomy components that are assembled during surgery to guide bone reduction. |
| Conventional double digital periodontal guide | Active comparator | Device: Conventional double digital periodontal guideParticipants undergo esthetic crown lengthening using a conventional one-piece double digital periodontal guide |
Who may qualify
- Ages
- 21 to 60 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult
Key inclusion criteria (5 listed)
- Patients both genders aged from 21-40 years
- Patients complaining of Excessive gingival display (3mm or more gingival display at full smiling).
- Patients with Altered passive eruption (APE) type 1 B Coslet GJ et al., 1977).
- Patients have thick gingival phenotype (thickness of gingiva is ≥ 1 mm) (Greenberg J et al., 1976).
- Patients with healthy periodontium and no active periodontal disease, with good plaque control and stable gingival health prior to surgery.
Key exclusion criteria (7 listed)
- Pregnant and lactating females.
- Poor oral hygiene.
- Smokers.
- Patients with systemic diseases which could influence the outcome of the therapy e.g. (Diabetic patients, bleeding disorders).
- Patients on immunosuppressive therapy or long-term corticosteroids.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Stackable double digital periodontal guideA custom-made, 3D-printed digital surgical guide used during esthetic crown lengthening. The guide consists of two detachable components: a gingivectomy guide for soft tissue incision and an ostectomy guide that is joined after flap reflection and positioned directly on the alveolar bone to guide bone reduction. The guide is designed using merged cone-beam computed tomography (CBCT) and intraoral scan data to improve the accuracy of bone reshaping. | Device | Stackable double digital periodontal guide |
| Conventional double digital periodontal guideAlso: double periodontal guide, digital periodontal guide, dual periodontal guide, dual digital periodontal guideA custom-made, one-piece 3D-printed digital surgical guide used during esthetic crown lengthening. The guide directs both the gingivectomy and ostectomy based on the planned treatment using intraoral scan data . After flap reflection, the guide is repositioned to guide bone reduction from the soft tissue level. | Device | Conventional double digital periodontal guide |
Primary outcome
Difference in accuracy of both guides
Time frame: 6 months
Evaluation of the degree of matching of the post operative actual gingival zenith points with the virtual predicted presurgical plan. Intraoral digital scanning for both groups will be obtained preoperative, immediately after surgery, and follow up appointments at 6 weeks and 6 months after surgery and exported in STL file format then it will be superimposed on the digitally designed diagnostic STL file to obtain statistical differences.The accuracy can be measured by comparing the planned surgery and the actual result of the surgery Linear measurement in millimeters.
6 secondary outcomes
Bone level accuracy
Time frame: 6 months
Gingival margin stability
Time frame: 6 Months
Pink Esthetic Score
Time frame: 6 months
Surgical time
Time frame: time of the surgery
Patient satisfaction
Time frame: 2 weeks
analgesics
Time frame: 2 weeks
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 23 Oct 2026.
- Related InfoLink provided by the sponsor.
- Individual participant dataSharing planned: Undecided
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
Questions about this trial
What is this clinical trial studying?
A study testing Stackable double digital periodontal guide and Conventional double digital periodontal guide in people with Gummy Smile of Altered Passive Eruption Type 1B, run by Ain Shams University.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 5 inclusion and 7 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: opening soon, as of the sponsor's last update on 23 Oct 2026. Status can change between updates, so confirm with the study contact before making plans.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Farah M Elshaer, postgradaute student (+201008936993, farahelshaer@dent.asu.edu.eg), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Difference in accuracy of both guides (time frame: 6 months). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 23 Oct 2026; AzTrials last refreshed its copy on 26 Oct 2026.