The Efficacy of Different Gingival Displacement Methods Before Definitive Digital Impression

Study Overview
=================
Brief Summary
-----------------
This study aims to evaluate and compare the efficacy of four methods in achieving vertical and horizontal gingival tissue displacement to be captured by optical digital impression. Moreover, the effect of the gingival displacement methods on the periodontal tissues around the final restoration will be assessed.

Official Title
-----------------
The Efficacy of Different Gingival Displacement Methods Before Definitive Digital Impression: A Randomized Controlled Clinical Trial

Conditions
-----------------
Gingival Displacement

Intervention / Treatment
-----------------
* Device: Laser troughing
* Other: Retraction cord and astringent
* Other: Cordless retraction paste with astringent
* Other: Cordless retraction paste without astringent


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Patients having normal occlusion. Good oral hygiene with no signs of periapical pathology or periodontal disease (plaque index score ≤10). Clinically and radiographically healthy gingiva and periodontium around the abutments with no evidence of attachment loss. Thick gingival biotype (determination using color coded probe). Patient having natural teeth as opposing dentition. Gingival sulcus of the abutment teeth (≤ 3mm). Adequate abutment tooth length for retention without deep subgingival extension (not more than 0.5mm) Exclusion Criteria: Pregnancy, which prevents the use of diagnostic x-rays. Parafunctional habits. Mobility of abutment teeth. Gingival Recession Patient presenting allergy to materials being used. Smoking. Medical history that could affect their periodontal condition.

Ages Eligible for Study
-----------------
Minimum Age: 25 Years
Maximum Age: 40 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Other
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Laser troughing<br> | Device: Laser troughing<br>* Laser troughing will be carried out by passing laser optic fiber in contact mode along the gingival sulcus. Laser energy will be delivered with a wavelength of 980nm and power of 0.8W, in continuous mode. Laser tip will be inserted 1mm into the gingival sulcus, to facilitate an accurate recording of finish line<br>|
| Experimental: Retraction cord and astringent<br> | Other: Retraction cord and astringent<br>* Partial isolation of the tooth with cotton rolls and saliva ejector will be performed. Appropriate size of retraction cord will be soaked in astringent for 5 mins. Then packing of the cord will be started from the mesial interproximal area by gently packing into the sulcus with the gingival cord packer instrument using the single cord technique. Retraction cord will be kept in place for 5 minutes. Cord will be removed immediately before the start of the intraoral scan<br>|
| Experimental: Cordless retraction paste with astringent<br> | Other: Cordless retraction paste with astringent<br>* The cordless paste with astringent will be injected gently into the sulcus, leaning on the tooth at the point of the cervical limit and not on the gingiva, the cannula will remain parallel to the axis of the tooth to exert optimal pressure. Then it will removed after 5 mins with copiously irrigated water until no traces of the materials left.<br>|
| Active Comparator: Cordless retraction paste without astringent<br> | Other: Cordless retraction paste without astringent<br>* The cordless paste without astringent 10 will be injected into the sulcus of the gingiva. The suitable size of Comprecap will be held on the abutment to push the material deep into the sulcus of the gingiva, and the participants will be informed to bite over it for a period of 3 to 5 minutes. After 5 minutes, the comprecap with the set retraction material attached to it, will be removed from the patient mouth.<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Horizontal displacement measurement | All measurements were obtained from the definitive digital impression by using dental intraoral scanner software. Horizontal displacement was measured as the distance from the most prominent point of the crest of the marginal gingiva to the finish line in the same crowns section (in the same plane). | up to one month | 
| Vertical Displacement measurement | All measurements were obtained from the definitive digital impression by using dental intraoral scanner software. Vertical displacement will be measured as the distance from the most prominent point of the finish line to the deepest point of gingival sulcus. | up to one month | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Dental plaque measurement | Using the plaque index of Silness and Loe. Each tooth will be scored from 0-3 according to the amount of plaque accumulation. 0: No plaque in the gingival area. A film of plaque adhering to the free gingival margin and adjacent area of the tooth. The plaque may only be recognized by running a probe across the tooth surface. Moderate accumulation of soft deposits within the gingival pocket, on the gingival margin and/or adjacent tooth surface, which can be seen by the naked eye. Abundance of soft matter within the gingival pocket and/or on the gingival margin and adjacent tooth surface. | up to one month | 
| Gingival inflammation measurement | Using the gingival index of Silness and Loe. Each tooth will be scored from 0-3 according to the degree of gingival inflammation. 0: Normal gingiva Mild inflammation - slight change in color, slight oedema. No bleeding on probing Moderate inflammation-redness, oedema and glazing. Bleeding on probing Severe inflammation - marked redness and oedema. Ulceration. Tendency to spontaneous bleeding | up to one month | 
| Gingival Height loss measurement | Complete arch maxillary digital impressions (postoperative scans) will be made for each patient by using intraoral scanner after cementation of the crowns. The postoperative scans will be superimposed by the pre-operative scan. A cross sectional line will be drawn in the middle of the superimposed scans and the measurements will be done at 2 points (midbuccal and midlingual). The distance from the gingival margin of the preoperative scan to that of one postoperative scan will be considered gingival height loss at the scan's timepoint | up to one month |