Long palatal connective tissue rolled pedicle graft with demineralized freeze-dried bone allograft plus platelet-rich fibrin combination: A novel technique for ridge augmentation - Three case reports.

Replacement of missing maxillary anterior tooth with localized residual alveolar ridge defect is challenging, considering the high esthetic demand. Various soft and hard tissue procedures were proposed to correct alveolar ridge deformities. Novel techniques have evolved in treating these ridge defects to improve function and esthetics. In the present case reports, a novel technique using long palatal connective tissue rolled pedicle graft with demineralized freeze-dried bone allografts (DFDBAs) plus Platelet-rich fibrin (PRF) combination was proposed to correct the Class III localized anterior maxillary anterior alveolar ridge defect. The present technique resulted in predictable ridge augmentation, which can be attributed to the soft and hard tissue augmentation with a connective tissue pedicle and DFDBA plus PRF combination. This technique suggests a variation in roll technique with DFDBA plus PRF and appears to promise in gaining predictable volume in the residual ridge defect and can be considered for the treatment of moderate to severe maxillary anterior ridge defects.

INTRODUCTION

Replacement of missing maxillary anterior tooth with residual ridge defect is challenging, considering the high esthetic demand. Esthetic outcome of fixed prosthetic denture depends on three dimensional emergence profile of the pontic design, tooth shape, and shade. Emergence profile of the pontic depends on residual alveolar ridge volume, width, and length. A detailed treatment planning is required for achievement of a predictable esthetic outcome for anterior ridge defects.

A localized residual alveolar ridge defect is characterized by deficiency of volume of bone and mucosal tissue. Seibert[1] classified the localized alveolar ridge defects into Class I, Class II and Class III based on horizontal, vertical ridge deficiency. Allen et al.[2] classified the ridge defects as mild: Depth <3 mm, moderate: Ranging from 3 mm to 6 mm and severe: >6 mm, considering the relation of depth of the deformity to the adjacent alveolar bone level.

Various soft and hard tissue procedures were proposed to correct alveolar deformities.[3] Hard tissue augmentation procedures include, autologous block grafts, bone grafts and substitutes[345] and guided bone regeneration.[6] The soft tissue ridge augmentation procedures include, onlay free mucosal,[7] inter positional connective tissue grafts,[8] pouch graft,[9] roll pedicle grafts[10] and modified roll pedicle grafts.[111213]

Roll pedicle graft technique proposed by Abrams[10] comprises de-epithelization of a palatal pedicle flap and exposure of palatal bone. This pedicle is rolled under the buccal mucosa to increase the buccolingual dimension of the edentulous ridge for later fabrication of a fixed prosthesis. The flap is released by two vertical incisions extended beyond the mucogingival junction. Modified roll technique using a “trap-door” approach was proposed to cover the palatal bone,[11] in which the epithelium over the palatal connective tissue is raised and preserved to cover the palatal bone. Barone et al.[12] further modified the roll technique with intrasulcular incisions forming a full thickness “envelope” on the buccal aspect instead of the two buccal releasing incisions. Gasparini proposed L shaped incision design on palate to harvest double fold connective tissue pedicle graft to increase the buccopalatal dimensions of the ridge defect.[13]

Platelet-rich fibrin (PRF) is a second generation platelet concentrate used in conjunction with bone grafts, which offers several advantages including promoting wound healing, bone growth and density, graft stabilization, wound sealing, hemostasis and improving the handling properties of graft materials.[141516]

The present case reports demonstrate a novel technique using modified rolled palatal pedicle connective tissue graft with demineralized freeze-dried bone allograft (DFDBA) plus PRF combination to correct the localized maxillary anterior alveolar ridge defects.

CLINICAL DESCRIPTION

Three systemically healthy patients reported to the Department of Periodontology with the chief complaint of missing tooth in maxillary anterior region. Intraoral examination revealed a severe alveolar ridge deformity in relation to missing maxillary left central incisor region [Figures 1a–e] and [Table 1]. The treatment options including autologous block grafting followed by implant placement and ridge augmentation followed by fixed partial denture were explained to the patient. All the patients opted for the second procedure, and informed consent was obtained from each patient. All the patients had undergone thorough oral prophylaxis prior to the surgical procedure.

Figure 1

(a, b) Preoperative facial and occlusal view showing localized Class III ridge deformity in maxillary left central incisor region of case 1. (c) Preoperative occlusal view showing localized Class III ridge deformity in maxillary left central incisor region of case 2. (d) Preoperative occlusal view showing localized Class III ridge deformity in maxillary left central incisor region of case 3. (e) Line diagram showing localized alveolar ridge defect

Table 1

Preoperative and postoperative dimensions of ridge defects

After administration of local anesthesia (2% lignocaine with 1:80,000 epinephrine), partial thickness horizontal incision was made on the palatal aspect of ridge at mesial line angle of right central incisor to mesial line angle of lateral incisor. From the horizontal incision line, an oblique incision was placed from mesial line angle of left lateral incisor to 2nd premolar [Figure 2a and b]. Care was taken to maintain at least 3 mm distance from the gingival margin of teeth to the oblique incision. The partial thickness flap was reflected from oblique incision line to expose the underlying connective tissue [Figure 3a and b]. The palatal connective tissue pedicle graft was then outlined by giving full thickness incision along the oblique incision line, and another parallel incision was given from the mesial line angle of central incisor. These parallel incisions were joined by a horizontal incision at the apical end. Care was taken to avoid damage to the nasopalatine, and greater palatine nerves and vessels. The length of the palatal connective tissue pedicle graft was approximately 2 times more than the apico coronal length of the ridge defect [Figure 4a and b].

Figure 2

(a) Operative view showing incision lines for harvesting palatal connective tissue pedicle graft. (b) Line diagram showing incision lines for harvesting palatal connective tissue pedicle graft

Figure 3

(a) Operative view showing palatal connective tissue after partial thickness flap reflection. (b) Line diagram showing palatal connective tissue after partial thickness flap reflection

Figure 4

(a) Operative view showing long palatal connective tissue pedicle graft. (b) Line diagram showing long palatal connective tissue pedicle graft

The palatal pedicle graft was reflected coronally up to the crest of the ridge defect. From the crest of the ridge defect a partial thickness incision was made extending beyond the line angles of adjacent incisors and mucogingival junction, leaving the periosteum on the bone [Figure 4a and b]. The pedicle graft was rolled from the apical end and secured with 5–0, prolene horizontal loop suture to the labial flap [Figure 5a].

Figure 5

(a) Operative view showing pedicle graft rolled into labial flap. (b) Placement of demineralized freeze-dried bone allografts plus Platelet-rich fibrin into ridge concavity. (c) Line diagram showing placement of bone graft into ridge concavity

Later periosteum from crest of the defect was reflected up to vestibular fornix for the placement of DFDBA (Tata memorial, >500 to < 1040 μm) bone graft material mixed with PRF. PRF was prepared just preceding to surgery; intravenous blood from the antecubital vein was collected in a 10-ml sterile tube without anticoagulant and instantly centrifuged at 3,000 revolutions per minute for 10 min. PRF was easily separated from red corpuscles base using a sterile tweezers and scissors and then transferred onto a sterile dappen dish. PRF was mixed with DFDBA and then placed onto the ridge defect [Figures 5b and 5c].

Prior to placement, bleeding points were induced on the bone to enhance the blood supply. Later labial flap and palatal flap were approximated with external horizontal mattress suture; independent direct sutures were placed along the oblique incision on the palate from mesial line angle of lateral incisor to 2nd premolar region using 5–0 prolene suture [Figures 6a–c]. Temporary ovate pontic Maryland bridge was made to create an emergence profile on the ridge, and periodontal pack was placed on the palatal aspect [Figure 7].

Figure 6

(a) Operative view showing placement of suture on the incision line palatally. (b) Operative view showing placement of external horizontal mattress suture on the labial aspect. (c) Line diagram showing placement of suture on the incision line

Figure 7

Postoperative view showing temporary ovate pontic Maryland bridge

The patient was prescribed 500 mg amoxicillin every 8 h for 5 days and 800 mg ibuprofen every 6 h as needed. The patient was advised to rinse using 0.12% chlorhexidine gluconate mouthwash twice daily for 3 weeks. Written and verbal postoperative instructions were given to the patient.

Clinical outcome

Healing of the augmented ridge and palatal donor sites was uneventful with no postoperative complications. The sutures were removed after 2 weeks. 2 months postoperative evaluation showed a considerable amount of ridge augmentation with soft tissue emergence profile [Figure 8a–d] and [Table 1].

Figure 8

(a, b) 2 months postoperative view showing increased ridge dimension of case 1. (c) 2 months postoperative view showing increased ridge dimension of case 2. (d) 2 months postoperative view showing increased ridge dimension of case 2

DISCUSSION

The present technique was proposed for the correction of severe maxillary anterior alveolar ridge defect by utilizing modified rolled palatal connective tissue pedicle graft and DFDBA with PRF. Abrams's roll technique employed for the correction of mild ridge defects leaves exposed palatal bone.[10] Modified roll technique, which was proposed by Scharf and Tarnow, covers the palatal bone,[11] but the tissue obtained in these techniques is sometimes minimal and not suitable for correction of moderate to severe ridge defects.

Gasparini proposed a double fold connective tissue technique, with L shaped incision given at right angle to the gingival margin of the adjacent tooth on the palate. The palatal pedicle graft achieved in this technique was more than the defect depth and double folded to the buccal flap. This technique was used for the moderate maxillary premolar ridge defects.[13]

The present technique, instead of L shaped incision an oblique incision was given from the line angle of adjacent lateral incisor up to second premolar. The oblique incision facilitates harvesting of maximum possible length of pedicle graft; the length of the pedicle should be >2 fold to the defect depth. The palatal pedicle connective tissue graft reduces the risk of graft necrosis due to its intact blood supply.

The present technique used PRF and DFDBA combination, which was earlier used for periodontal regeneration,[17] extraction socket and ridge preservation.[1819] PRF contains growth factors and accelerated tissue healing due to effective neovascularization, enhanced wound closing with swift tissue remodeling and bone formation.[141516] DFDBA helps in new bone formation through osteoconductive and osteoinductive property.[17] The present technique resulted in predictable ridge augmentation, which can be probably attributed to the soft and hard tissue augmentation with a connective tissue pedicle and DFDBA plus PRF combination.

CONCLUSION

The present technique can be considered for the treatment of moderate to severe maxillary anterior alveolar ridge defects.