Reconstruction of interdental papilla using autogenous bone and connective tissue grafts.

Previous studies have reported the management of Class I and II papillary defects, but knowledge on Class III defects, estimated to have a poor periodontal prognosis, remains minimal. In this case report, a Class III papillary defect reconstruction was attempted mainly since the patient reported with difficulty in phonetics. In Stage I, autogenous bone graft from the maxillary tuberosity and subepithelial connective tissue graft was augmented to decrease the distance between the interdental bone crest and contact point, simultaneously achieving a switch in the periodontal biotype. In Stage II, subepithelial connective tissue graft was augmented to achieve papillary fill. To avoid manual errors associated with quantifying the posttreatment outcomes, image data processing ImageJ software was used to assess the length, perimeter, and surface area of papillary loss using the preoperative images.

INTRODUCTION

The amount of teeth and gingival display are detrimental factors in obtaining an esthetic smile.[1] Two main areas to be addressed with regard to periodontal esthetics are gingival recession resulting in denuded root surface and loss of interdental papilla resulting in black triangle, especially in maxillary anterior teeth.[2] Currently, there are various predictable surgical techniques available to correct denuded root surface; however, there are no predictable techniques for reconstruction of lost interdental papilla.[3]

A thorough understanding and analysis of factors that affect the integrity of the interdental papilla is essential to restore it.[1] The long-term stability of the interdental papilla depends on the anatomical environment, distance between contact point and bone crest, inter-radicular distance, size of the interdental space, tooth shape, and periodontal biotype. Among these factors, the most important parameter is the distance from the interdental crest to the apical portion of the contact point. Tarnow et al. stated that the distance of 5 mm is critical for this purpose.[4] Studies have shown that on comparing the length of contact area and height of papilla, a 50:50 relationship would be stable. That is 50% of overall tooth length is the contact length and the remaining 50% is the papilla.[5] Hence, papillary loss can result from interdental papilla positioned apically which is commonly caused by periodontal disease or due to alterations in contact length resulting in open gingival embrasures.

Height of the interdental papilla is determined by the level of interproximal bone, patients' biological width, size, and shape of gingival embrasure. When the bone level moves apically such as in periodontal disease, interdental papilla also has a potential to move apically. The distance, i.e., the papilla stands above the bone, is influenced by the patients' biological width and volume of gingival embrasure. Hence, the sulcus depth rather than the distance above the bone is detrimental to the behavior of papilla during treatment.[67]

Recession is also linked to periodontal biotype. When papillary loss occurs due to loss of bone interdentally, thereby lengthening the distance from the contact point, it is essential to create a predictable status for papillary reconstruction by augmenting the bone.[8] When the papillary loss occurs due to wide embrasure, the underlying cause should be carefully assessed and rectified (orthodontic and or restorative corrections), and this must be done before papilla augmentation.

Another common problem encountered in esthetic procedures is the documentation and interoperator variability of estimating and understanding the results. The use of numerical values from computer-based software can substantiate the outcome scientifically. ImageJ software is a Java-based image-processing program that was developed by the National Institute of Health to solve many image processing and analysis problems.[9]

This article highlights a technique to reduce the distance from the contact point to crest using autogenous bone graft and subepithelial connective tissue graft to switch the periodontal biotype and augment the papilla. It also highlights the use of imaging software to substantiate the outcome of the procedure.

CASE REPORT

A 26-year-old male patient reported to the Department of Periodontics, Faculty of Dental Sciences, Sri Ramachandra University, complaining of an unesthetic space in relation to the front tooth region and also had difficulty in pronouncing certain alphabets due to the space between the teeth. Examination revealed papillary recession due to inadequate osseous support [Figure 1a]. It was classified as Class III based on the Nordland and Tarnow's classification[10] and estimated to have a poor periodontal prognosis. The teeth were triangular in shape with a thin periodontal biotype. Baseline clinical parameters were recorded in millimeters using a manual periodontal probe (UNC-15, Hu Friedy Co., Chicago, IL, USA) [Table 1]. Intraoral radiographs revealed that distance from the bone crest to the contact point was 12.03 mm [Figure 1b].

Figure 1

Preoperative view of gingival papillary recession. (a) Frontal aspect; (b) Intraoral radiograph

Table 1

Baseline clinical parameters were recorded using UNC 15 probe (mm)

Despite the prognosis being poor, due to the patient's concern esthetically and phonetically, reconstruction of the lost papilla was planned in two stages. In Stage I, augmenting the inter-radicular bone and achieving a distance of 5 mm between bone crest and contact point were planned, followed by which the second surgery to augment the soft tissue was planned.

Preoperative site preparation

Nonsurgical therapy which included scaling and root planing was carried out. On the day of surgery, local anesthesia was achieved in the facial and palatal regions using 2% lidocaine hydrochloride with adrenaline (1: 100,000).

Stage I

Intrasulcular incisions and two vertical releasing incisions were made on either side of the papilla to raise a full thickness flap [Figure 2a]. Root conditioning was done using tetracycline for 30 s to aid in root demineralization. After achieving sufficient anesthesia in the maxillary tuberosity region, cancellous bone was harvested. The bone graft was trimmed to form a saddle shape and was then stabilized at the recipient site using stainless steel screws [Figure 2b]. To switch the periodontal biotype, subepithelial connective tissue was harvested from the palate using the trap door technique.[11] Hemostasis was achieved using 3-0 silk sutures in the palatal region. The connective tissue graft was trimmed and placed over the recipient site and stabilized [Figure 2c]. Flaps were coronally advanced and sutured using resorbable 5-0 Vicryl with suspensory sutures as described by Nordland et al.[12] [Figure 2d].

Figure 2

(a) Intrasulcular incisions and vertical releasing incisions were made on the facial aspect including the adjacent mesial and distal papilla; (b) Autogenous bone graft was harvested form the maxillary tuberosity and stabilized using stainless steel screws; (c) Connective tissue graft harvested from the palate was placed in the interdental space and secured in place using 5-0 Vicryl sutures; (d) Suspensory sutures were used to advance the flap coronally ensuring closure of the interdental space

On gaining satisfactory healing in 2 weeks, sutures were removed and the site was irrigated using saline. The patient was reviewed at regular intervals for three months, and oral hygiene instructions were reinforced.

Stage II

On reviewing the patient in 3 months, two goals had been achieved: The preoperative thin biotype had been switched to thick periodontal biotype [Figure 3a] and bone crest to contact point distance was decreased to 5 mm [Figure 3b]. In Stage I of surgery, the modification of semilunar technique by Han and Takei was used.[13] Intrasulcular incisions were given around the mesial and distal aspect of the papilla, and a semilunar incision was given at the level of the mucogingival junction [Figure 4a]. Connective tissue graft was harvested from palate using trap door technique,[11] and trimmed to the desired amount. It was then tucked into the recipient site, and the bulk of tissue that formed the gingivopapillary unit was advanced coronally to occupy the interdental embrasure space [Figure 4b]. Suspensory sutures were placed along with orthodontic brackets that were bonded to the tooth [Figure 4c].

Figure 3

(a) Postoperative aspect of treated area 3 months after Stage I; (b) Intraoral radiograph after augmentation in papillary region after 3 months

Figure 4

Stage II (a) intrasulcular incisions and semilunar incision were made at the height of the mucogingival junction on the facial aspect; (b) Connective tissue graft harvested from the palate was tucked into the recipient site; (c) Gingivopapillary unit was coronally advanced and sutured using suspensory sutures to an orthodontic bracket that was bonded to the labial surface of the tooth; (d) Postoperative healing 1 year after surgery

The patient was given postoperative instructions and advised Ibuprofen 400 mg twice daily for 3 days. The patient was advised to use chlorhexidine (0.2%) mouthrinse twice daily and avoid mechanical tooth cleaning of the surgically treated area. On reviewing the patient after 6 months, 90% papillary fill was achieved and the healing was satisfactory [Figure 4d].

All images were taken using Canon IXUS132 16MP Digital camera and analyzed using the imaging software (Image J Processing Software, the National Institute of Health, Bethesda, Maryland, US). The pixel measurements of ImageJ software were compared with UNC probe calibrations and set to a standard scale of 1 mm = 14.6 pixels [Figure 5]. The preoperative [Figure 1a], after Stage I [Figure 3a], and after Stage II [Figure 4d] were compared to the surface area, perimeter, and length of the lost interdental tissue (measured from the most apical point of the interdental papilla to the contact point) using ImageJ software [Figure 6]. The values were recorded according to the set scale [Table 2] and graphically represented [Figure 7].

Figure 5

Scale was set at 14.600 pixels/mm by comparing 1 mm calibrated UNC probe measurements and ImageJ software

Figure 6

ImageJ software used to calculate (a) surface area; (b) length; and (c) perimeter

Table 2

Using ImageJ software the surface area, perimeter, and length of the lost interdental tissue was evaluated

Figure 7

Comparison of surface area of lost Interdental papilla graphically represented

DISCUSSION

The following case report discusses a staged approach of surgical augmentation of the interdental papilla in a Class III papillary defect with inadequate osseous support resulting from periodontal disease. As the predictability of surgical augmentation of the lost interdental papilla still poses a problem and is not definitive, it is essential to keep in mind the key factors before the treatment planning.[12] An increased distance from the contact point to the alveolar crest is a significant factor in deciding the treatment plan.[4] This can result due to either the loss of interdental bone in the corresponding area or due to a coronally located contact point (short contact length) with adequate osseous support. In the following case report, although Class III defect is proposed to have a poor prognosis since the patient reported not only with an esthetic concern but also complained about difficulty in pronouncing certain alphabets, a stepwise treatment protocol was drawn out to achieve predictable coverage through surgical augmentation. On examination, the contact length (6 mm) in correspondence with the tooth length (11 mm) was adequate and maintained a 50:50 ratio. However, the loss of alveolar bone height in the interproximal area due to periodontal disease resulted in an increased distance between the alveolar crest and the apical portion of the contact point (12.03 mm). Tarnow et al. stated that for long-term stability and success, it was necessary to maintain a distance of 5 mm between the contact point and alveolar crest. In the above case, bone graft was harvested from the maxillary tuberosity due to the corticocancellous nature of bone native to the maxillary central incisor area. This Stage I surgery facilitated reducing the distance from the contact point to bone crest, thereby enhancing long-term predictability.[2]

Another important factor that is to be taken into consideration is the periodontal biotype. According to the classification by Siebert and Lindhe, the patient demonstrated a thin periodontal biotype.[14] A friable tissue could have led to an increased chance of relapse and postoperative recession following periodontal surgery. It is mandatory to achieve a proper biologic width for long-term stability.[15] To achieve this in Stage I of the surgery along with augmenting the interproximal bone, a simultaneous switching of the periodontal biotype using subepithelial connective tissue was carried out.

This was followed by Stage II, in which soft tissue augmentation of the lost interdental papilla was achieved. The use of Han and Takei's modification[1316] of the semilunar flap design in Stage II limits the number of horizontal incisions, thereby maintaining the blood flow to the gingiva papillary unit as a whole along with the underlying subepithelial connective tissue graft.

To avoid manual error in quantifying the posttreatment outcome, image data processing ImageJ software was used to assess the length, perimeter, and surface area of papillary loss using the preoperative images and those that were taken after Stage I and Stage II. All three parameters showed significant improvement postoperatively. Using ImageJ, the lost interdental papillary space showed a variation in the length from 5 to 2.7 mm, surface area of 88 to 20 mm2, and perimeter variation from 12.1 to 5.5 mm preoperatively and after Stage II, respectively.

CONCLUSION

This case report clearly demonstrates a thorough analysis and understanding of factors along with surgical precision in rectifying them can give desired results with sustained long-term outcome even in Class III papillary defects.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.