Reconstruction of advanced bone defect associated with severely compromised maxillary anterior teeth in aggressive periodontitis: a case report

A 34-year-old systemically healthy Malay woman was referred to the Periodontics Specialist Clinic of the Kulliyyah of Dentistry, International Islamic University Malaysia, with a chief complaint of bleeding gums and mobility of her upper anterior teeth. Complete medical and dental histories were taken, and a full periodontal chart was recorded, including all the clinical periodontal parameters, plaque scores and bleeding on probing (BOP), probing pocket depth (PPD), clinical attachment loss (CAL), recession, mobility, and furcation involvement. The chart revealed grade II mobility of the UCI and pus discharge with deep probing depths and severe CAL >6mm. The three-dimensional picture in Fig. 1 shows the circumferential bone resorption surrounding the UCI. The rapid rate of bone destruction affected the sites of the first and second molars, resulting in furcation involvement and mobility ranging from grade I to grade II with recorded PD and CAL greater than 6mm as well. The radiographic interpretation showed an angular bone defect mesial and/or distal to the first molars (Fig. 2). Because the patient was systemically healthy except for the presence of periodontitis, and based on the patient’s history, clinical periodontal records, and radiographic findings, she was diagnosed with localized aggressive periodontitis [15]. A combination of oral metronidazole 400mg and amoxicillin 500mg were prescribed for 7 days as an adjunct to scaling and root planing (SRP). Six weeks after the NPT, the affected sites were reevaluated. The results revealed slight reductions in the patient’s BOP, PD, and CAL. However, the range of residual bleeding pocket depths was from 5mm to 6mm with no obvious clinical attachment gain. Therefore, the decision was made to provide regenerative therapy, and a surgical treatment was scheduled for the patient in spite of the questionable prognosis that had been assigned at baseline. The patient was informed verbally regarding the details of the surgical treatment plan and signed a written informed consent form before each periodontal surgical procedure as part of the clinical protocol of our institute.

The surgical procedure on the UCI included the use of a papilla preservation technique, which was applied to preserve the papilla and obtain primary closure of the inter-dental space (Fig. 3a). The technique of papilla preservation [16] that we applied, compared with the modified technique [17], provides better access to the palatal defect because it is applicable on the buccal and palatal aspects. Therefore, the incorporation of papillae with the facial part of the flap (Fig. 3a) was achieved through crevicular incisions made around each tooth without splitting the inter-dental papilla, and a semi-lunar incision was made across the palatal aspect of at least 5mm from the papillary crest, taking advantage of the keratinized palatal mucosa in protecting the graft during healing. Additionally, this palatal approach overcomes the post-operative labial scar formation in the aesthetic zone.

As a result of the intra-bony defect location, which is associated with two adjacent central incisors, significant supra-crestal components of the defect presented at the palatal area (Fig. 1). The circumferential intra-bony defects were thoroughly debrided (Fig. 3b), and cerabone bovine xenograft granules (botiss biomaterials, Zossen, Germany) were used to fill the defects. An OsseoGuard resorbable bovine collagen membrane (Collagen Matrix/BIOMET 3i, Palm Beach Gardens, FL, USA) covered the bone substitute, with delicate trimming of the membrane done to extend inter-proximally (Fig. 3c) using sling sutures of absorbable material to adapt the membrane well and prevent its collapse over the bone graft. The flap was sutured using an internal horizontal mattress suture, which has the advantage of providing a tension-free flap (Fig. 3d) and a stable support for the grafting area. Simple interrupted sutures were applied at the rest of the flap sites. The sutures were removed 10 days after the surgical procedure. A fixed retainer using twisted wire (177.8mm; 3M Unitek, Loughborough, UK) was constructed palatally to splint the anterior teeth and stabilize the wound healing (Fig. 4). This type of wire allows long-term stability with physiologic tooth movement.

Strict oral hygiene instructions were given; however, the patient was asked to avoid normal brushing and flossing in the treated area for 4–6 weeks and replace it with the use of 0.12% chlorhexidine mouthwash. The modified Stillman brushing method was recommended to prevent the interference beneath the gingival margin until complete resorption of the membrane was achieved. During the healing process, professional plaque control was scheduled every 2 weeks to prevent bacterial contamination of the surgical area. The patient was also instructed not to chew on the treated area for the first 4 weeks.

The application of the graft and barrier membrane resulted in remarkable bone gain and support for more than two-thirds of the root length of the UCI, as shown in the radiograph taken at 2 years (Fig. 5b), which confirmed the resolution of the defect present at baseline (Fig. 5a). There was absence of BOP, significant PD reduction up to 2mm, and greater than 5mm attachment gain. Additionally, there was almost an equivalent amount of attachment gain and bone fill. The intra-oral photographs in Fig. 6 show the clinical improvement in the gingival tissue from edematous bleeding gingiva (Fig. 6a) to the closely adapted, firm, non-bleeding sites (Fig. 6b). Furthermore, Fig. 6b depicts a good post-operative result without any inter-proximally soft tissue crater formation, which explains the pre-requisite of the papillary preservation technique.

Three more regenerative periodontal surgeries were performed for regions of teeth 46, 26, 27, and 36. In these procedures, we used different xenograft bone granules of bovine origin (Endobone from Collagen Matrix/BIOMET 3i and Bio-Oss from Geistlich Biomaterials, Wolhusen, Switzerland) and achieved successful results in respect to bone fill (Fig. 7) compared with baseline (Fig. 2). The patient was covered with systemic antibiotics for all periodontal regenerative surgical procedures. A decision was made to extract the partially erupted and angulated third molars because these teeth were either without antagonists or compromising the adjacent second molars. They also presented difficulties in self-performed plaque control and acted as a local factor for plaque accumulation in deep periodontal pockets. The surgical extractions were performed during the surgical periodontal therapy to minimize the required treatment time and healing process.

During the phase of supportive periodontal therapy, the patient was treated with a schedule of professional plaque control with adjunct use of photodynamic therapy (PDT). The recall system of the maintenance phase was arranged every 3 months. At 2 years after baseline, the full periodontal chart revealed a marked improvement in the clinical periodontal records, as the percentage of sites with BOP had decreased from 40% to 16% and there was a substantial decrease in the number of deep pockets, characterized by the absence of PPD greater than 4mm compared with 22.22% before the commencement of treatment. This PPD reduction was accompanied by an average CAL gain of 3.07mm.

Written informed consent was obtained from the patient for publication of this case report and any accompanying images. A copy of the written consent is available for review by the Editor-in-Chief of this journal.