Radiographic Evaluation of a Star-shaped Incision Technique

Study Overview
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Brief Summary
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To evaluate a star-shaped incision technique to thick-gingiva and thingingiva patients treated with implant-supported fixed prosthesis. The star-shaped incision would be an effective and simple method to reconstruct gingival papillae and avoid the gingival recession in thick-gingiva patients treated with implant-supported fixed prosthesis, and it is worthy of clinical extend.

Detailed Description
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Objective: To evaluate a star-shaped incision technique to thick-gingiva and thin-gingiva patients treated with implant-supported fixed prosthesis. Methods and Materials: 24 patients received cross-shaped incision were assigned into thick-gingiva group (16 cases) and thin-gingiva group (8 cases). Follow-up examination was carried out 3 and 12 months after final restoration. Clinical and radiographic evaluation including gingival papilla height, modified plaque index, modified sulcus bleeding index, periodontal depth, and crestal marginal bone level were utilized.

Official Title
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Radiographic Evaluation of a Star-shaped Incision Technique for Thick-gingiva and Thin-gingiva Patients Treated With Implant-supported Fixed Prosthesis: a Randomized Trial

Conditions
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Clinical and Radiographic Effect, Thick-gingiva, Thin-gingiva, Implant

Intervention / Treatment
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* Diagnostic Test: The biotype of gingiva


Participation Criteria
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Eligibility Criteria
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Inclusion criteria Good general health, no chronic systemic diseases. All subjects included in this study needed to have one missing premolar or molar teeth with adjacent natural teeth. All subjects included in this study had been treated with one bone-level implant insertion in the premolar or molar region. The patients had insufficient gingival papilla height (referred to contralateral natural tooth which also had insufficient gingival papilla height) and at least 2 mm of keratinized tissue width around the implant. Exclusion criteria Active periodontal infections. Heavy smoking (> 10 cigarettes per day).

Ages Eligible for Study
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Minimum Age: 22 Years
Maximum Age: 58 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| thick-gingiva group<br>After the insertion of the probe into the facial aspect of the sulcus through the gingival margin, the simple visual method is based on the transparency of the periodontal probe through the gingival margin while probing the buccal sulcus at the midfacial aspect of the tooth. When the outline of the underlying periodontal probe can't be seen through the gingival, the gingival phenotype is considered thick. | |
| thin-gingiva group<br>After the insertion of the probe into the facial aspect of the sulcus through the gingival margin, the simple visual method is based on the transparency of the periodontal probe through the gingival margin while probing the buccal sulcus at the midfacial aspect of the tooth. When the outline of the underlying periodontal probe can be seen through the gingival, the gingival phenotype is considered thin. | Diagnostic Test: The biotype of gingiva<br>* The biotype of gingival was determined by periodontal probe.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Papilla height | Presence/absence of papilla height was assessed visually according to the papilla index proposed by Jemt | Between June 2019 and June 2021 | 
| Modified Plaque Index (mPI) | plaque accumulation around the marginal peri-implant tissue was assessed by the criteria of mPI | Between June 2019 and June 2021 | 
| Modified Sulcus Bleeding Index (mBI) | the bleeding tendency of the marginal peri-implant tissue was evaluated using mBI | Between June 2019 and June 2021 | 
| Probing Depth (PD, mm) | PD was assessed at the mid-buccal, mid-oral, mesial and distal aspects of the buccal surfaces of each implant with a standard periodontal probe, and final value was determined by the average of four aspects. | Between June 2019 and June 2021 | 
| Gingival margin level (GML) | gingival margin level was assessed by calculating the vertical distance between the most apical point of gingival margin at the buccal aspect of the crown and line connecting the peak of the adjacent mesial and distal natural teeth (PMD) | Between June 2019 and June 2021 | 
| The landmarks of first bone-implant contact (fBIC) and implant shoulder (IS) | fBIC-IS was defined as the vertical distance the first bone-implant contact to implant shoulder, and the distance was assessed at the mesial and distal aspect of implant, respectively. When the marginal crestal bone was located coronal to the IS, a positive (+) value was given, where a negative (-) value when located apically to the IS, the value was deemed as zero when IS and fBIC coincided. The crestal bone level at the time of impression taking was regarded as baseline. The known implant length was used for the calibration of dimensional distortion in the radiograph (the length of implant was 10 mm). | Between June 2019 and June 2021 |