Research objective: The aim of conducting this research is the development of a newer,
less invasive and cost-effective therapeutic approaches that help in management of
periodontal intrabony defects. Due to the shortcomings of other bone substitute
materials, another bone substitute material that would be completely autogenous and
cost-effective is required. Grafting autogenous demineralized dentin has been used
extensively for socket preservation and showed promising results in addition to being
cost-effective.

Research Procedure in brief:

This study will be carried out on patients enrolled from the Outpatient Clinic of Oral
Medicine and Periodontology department, Faculty of Dentistry, Cairo University.

Eligibility criteria:

I. Inclusion criteria:

Patient-related criteria:

- Motivated patient 18 years of age or order.

- Patient consulting in the outpatient clinic.

- Patient ready to perform oral hygiene instructions.

- Provide informed consent.

- Accepts the 6 months follow-up period.

Teeth related criteria:

- Tooth with two or three-walled intra-bony defect, probing depth ≥ 5mm with intra
osseous defect ≥ 3mm.

- Mature permanent tooth.

- Unrestorable tooth or fractured tooth beyond restoration, impacted third molar or
supernumerary tooth to be extracted and used as whole tooth graft inside the
intrabony defect.

II. Exclusion criteria:

Patient-related criteria:

- Medically compromised patients.

- Pregnant women.

- Uncooperative patients.

- Smokers.

- Systemic diseases that may compromise healing or bone metabolism (e.g diabetes,
hyperthyroidism).

- Failure to maintain good oral hygiene.

Teeth related criteria:

- Teeth with supra-bony defects.

- Teeth with grade III mobility.

- Teeth having interproximal craters, grade III furcation involvement, and grade III
mobility.

- Presence of caries or overhanging restorations.

- Presence of peri-apical injuries.

General operative procedure:

- The selected participants will be informed about the nature of the research and its
procedures, then written informed consent will be obtained.

- The surgical procedure will be explained to all patients prior to surgery.

- Patients diagnosed with periodontitis who meet the inclusion criteria will be
screened for periodontal examination. Based on this examination, target sites will
be identified.

- Each patient will receive the initial phase of the therapy, which will include oral
hygiene instructions, supragingival and subgingival debridement using ultrasonic and
hand instrumentations and relieving of occlusal trauma if any.

Pre-surgical patient preparation (Re-evaluation phase):

- 4-6 weeks after the initial therapy, periodontal re-evaluation will be done to
confirm the sites that will require surgical therapy.

- Criteria used to indicate that surgery is required include the persistence of
interproximal defect with PD ≥ 5 mm, CAL ≥ 4 mm.

- An individually customized positioning stent will be fabricated for each patient and
a pre-operative periapical x-ray using parallel-angle technique will be employed
using X-ray film holding system to ensure accuracy and reproducibility of the
measurements.

- A periapical radiograph using paralleling technique using KCP film holder will be
performed for each patient to evaluate alveolar bone loss using DIGORA system.

Surgical procedures

- Pre-procedural mouth rinse using 0.2% chlorhexidine gluconate3 rinses for intraoral
antisepsis.

- Surgical sites will be anaesthetized using local anesthesia4.

- The defect-associated inter-dental papilla will be surgically approached either with
a diagonal incision following the pattern of the simplified papilla preservation
flap when the width of the inter-dental space is 2 mm or narrower or with a
horizontal incision according to the modified papilla preservation technique at
inter-dental sites wider than 2 mm.

- Flap elevation will be limited to the buccal flap.

- No inter-dental and/or lingual intra-sulcular incisions will be performed.

- After removal of the granulation tissue by careful dissection and root debridement,
the root surface will be chemically conditioned with a 2 min. application of an EDTA
gel.

The participants will be divided into two groups:

Intervention group:

• The participant's own freshly extracted tooth will be cleaned from periodontal
ligaments, cementum, soft tissue attachment, caries, or restorations (if present) and
have their crown decapitated, using a high- speed fine finishing stone and saline
irrigation. The pulp chamber and root pulp will be cleaned by split opening the root and
cleaning it out using a high-speed diamond bur. Subsequently, teeth will be ground, and
demineralized using a hand bone mill. Then the particles will be prepared by
demineralization of tooth particles in 0.6N hydrochloric acid5 for 30 min then washed
twice in saline and dried with sterile gauze. Then it will be used as a graft for the
intra-bony defect after modified minimally invasive surgical technique.

Control group:

- Modified minimally invasive surgical technique (M-MIST) will be performed in the
intra-bony defects, with autogenous bone graft placement. The graft will be
harvested from the retromolar area using automatic chip maker (ACM) bur and a hand
bone mill will be used to grind the chips into particles, then it will be placed in
the defect.

- For both groups, flaps will be approximated and sutured at the original position
with a 5-0 monofilament polypropylene suture material using simple direct loop
interrupted technique.

Post-operative care and follow-up

- Participants will be instructed to abstain from trauma on the operative site, not to
interfere with the suture and to avoid hot food or vigorous rinsing.

- Tooth brushing will be encouraged for other parts of the dentition and gentle tooth
brushing for the operative site will be advised to be resumed after two weeks.

- Participants will be prescribed Ibuprofen 600 mg.

- Chlorhexidine 0.12% mouthwash will be prescribed for gentle rinsing twice daily for
two weeks.

- Sutures will be removed two weeks after the surgery.

- All the subjects will be evaluated at 1, 3, and 6 months for clinical and
radiographic parameters. Outcomes:The results of Clinical attachment level (CAL)
gain, Linear bone fill, Gingival index (GI), Plaque index (PI), Probing pocket depth
(PPD), Gingival recession (GR), Bleeding on probing (BoP), Postoperative pain and
Patient satisfaction will be measured at baseline, 1 month, 3 months and after 6
months.