deficient interdental papillae witt be surgically reconstructed. in one group, connective tissue graft (SCTG) will be used for papillae augmentation, while in the other group, advanced platelet rich fibrin (A-PRF). the height of the papillae will be measured preoperatively as well as post operatively at 3, 6 ,9 and 12 months.

The aim of this study is to compare the effect of A-PRF membrane to SCTG when used as grafting material with the Han and Takei's approach to reconstruct receding interdental papilla and assess deference in papilla height between the study groups.

The clinical parameters that will be evaluated are:

• Papilla height (PH)
• Clinical attachment level (CAL)
• Probing depth (PD)
• Post-operative patients' satisfaction about the esthetic outcome
• Post-operative pain level among patients

Study settings:

This study will be conducted in the postgraduate periodontology clinics in the faculty of dentistry, Cairo University. The participants will be selected from the outpatient clinic of the department.

interventionsa:

The first visit:

• Eligible participants will be interviewed to report medical and dental histories.
• The participants will receive full mouth dental and periodontal examination.
• Initial periodontal treatment (supragingival scaling and sub gingival debridement) as indicated.
• Patients will be given oral hygiene instruction on proper tooth brushing and flossing.
• They will be advised to use chlorhexidine mouth wash 0.12% twice daily for 2 weeks.

Second visit:

After 4-6 weeks of initial therapy, patients will be re-examined, and the baseline clinical parameters will be recorded as follows:

• Full mouth plaque index and gingival index.
• Site specific plaque index and gingival index.
• Type of Papilla deficiency (classification).
• Papilla height
• Clinical attachment level
• Probing depth

The patients then will be randomly allocated to one of the study groups.

Test group:

Deficient papillae in this group will be treated surgically and A-PRF membrane will be used as a grafting material.

Preparation of A-PRF:

A-PRF preparation protocol will be as described by (Clark et al. 2018):

A blood sample of 10 ml will be obtained from the patient and immediately centrifuged at 1300 rpm for 8 minutes.

Control group:

In this group, papilla recession will be treated surgically and the SCTG will be used as a grafting material.

sample size calculation was based on a previous study. fourteen experimental subjects and 14 control subjects are required to be able to reject the null hypothesis that the population means of the experimental and the control groups are equal with probability (power) 0.8. The type I error probability associated with this test of this null hypothesis is 0.05.

To compensate for anticipated missing data during follow up, this number is increased to 16 per group.

Recruitment

• Patients will be selected from the outpatient clinic of the Oral Medicine and Periodontology Department, Faculty of Oral and Dental Medicine-Cairo University
• Screening of patients will continue until the target sample is achieved.

Allocation

Randomization:

Patients will be randomly assigned to either test or control group using computer generated randomization (www.randomizer.org) which will be performed by the supervisor. The patients will be allocated to either test or control group.

Allocation concealment mechanism:

The two groups will be equally prepared for both surgical procedures. Then the decision of which group will receive papilla treatment with A-PRF (test) and which will receive papilla treatment with SCTG (control) will be taken according to the randomized numbers placed in opaque sealed envelopes. The number will be picked by the supervisor.

Implementation:

• All patients who provide an informed consent for participation as well as fulfill the inclusion criteria will be randomized.

Inclusion Criteria:

• Be healthy adults older than 18 years of age and presenting at least one deficient papilla with papilla presence index 2 or 3
• Have Interproximal CAL ≤ 3 mm
• Have probing depth ≤ 3mm
• Distance between the alveolar bone crest and contact point is less than 7mm.

Exclusion Criteria:

• Smoking.
• Pregnancy and lactation.
• Carious and non-carious cervical lesion in the involved teeth around the papilla.
• Restoration in teeth around the papilla (filling, crown, bridge, facings, clasp of a partial denture).
• Open contacts and non-vital teeth
• Poor oral hygiene with plaque index > 20 %.
• Tooth mobility
• History of medication in the previous 3 months
• History of periodontal surgery in the site to be treated in the past 12 months