Introduction

Patients are more conscious of dental esthetics and are requesting more root coverage procedures.  This generates a need for clinicians to develop materials and techniques that will predictably satisfy these patient-centered esthetic demands.

According to the National Survey of Oral Health, 88% of seniors aged 65 years and more and 50% of adults aged 18-64 years have lost gingival form and function and have one or more sites with recession.  The prevalence and extent of recession increases progressively with age.^1,2  Although several techniques have been proposed to achieve consistent and predictable root coverage, by some estimates, the average percentage of covered root surfaces resulting from different procedures performed under varying clinical conditions varies from 56% to 97.8%.^3,4,10  Thus treatment of buccal recession remains a major challenge to clinicians.

Root coverage techniques currently used by most clinicians include pedicle grafts (lateral sliding or double papillae) with or without connective tissue grafts, epithelialized autogenous grafts (free gingival), connective tissue grafts, coronally positioned flaps (CPF) alone, CPF preceded by a free gingival graft, and CPF with a simultaneous connective tissue graft.  Each of these techniques result in varying degrees of success and offer a variety of treatments for such defects.³

A new acellular dermal allograft tissue (Alloderm^{® £}) has been recently introduced for use in dentistry, although it has been used in medicine for full-thickness burns,^1,12 the revision of depressed scars and nasal reconstruction,¹³ facial defect repair,¹⁴ lip augmentation,^15,16 and septal perforation repair.¹⁷  In dentistry, its uses include substitution for palatal donor tissue in soft tissue surgeries around natural teeth and implants to increase the zone of keratinized tissue,¹⁸ for tissue augmentation,¹⁹ and for root coverage.^20,21  The intent of these procedures is principally to create a tissue barrier that is more resistant to further recession due to trauma.  Other indications include soft tissue flap extension over bone graft, amalgam tattoo correction, and soft tissue defect repair (Table 1).

Advantages and Disadvantages of Acellular Dermal Graft Material
Table 1 lists the advantages and disadvantages of the acellular dermal graft material.  Acellular dermal graft material can be used to treat larger areas of recession with just one surgical site, with less time, and with good aesthetic results.  Disadvantages include longer healing time, additional cost of material, and the learning curve associated with the handling of the material.

Processing of the Acellular Dermal Graft Material
During the processing of AlloDerm^® acellular dermal graft material, the epithelium is first removed from the donor tissue while the basement membrane is retained to promote faster reepithelialization.  Next, cells are removed from the remaining tissue by a series of detergents that eliminate the chance for an antigenic response by the recipient.  The tissue is then freeze-dried and packaged for immediate use.  The graft material consists of a connective tissue surface which readily absorbs blood and a basement membrane surface that does not allow for blood absorption.

Technique for Root Coverage Using Acellular Dermal Graft Material
(Pre-Operative Video Clip)  The surgical procedure consists of a coronally positioned flap and placement of the acellular dermal graft material.¹⁴  Prior to incision, the teeth are scaled to remove any debris, then conditioned by burnishing the exposed root(s) with one of the following:  tetracycline (100 mg/ml for 4 minutes), citric acid (aqueous pH 1 for 2-3 minutes) or EDTA (pH 7.3 for 2-3 minutes) (Video Clip 1).  Bleeding points equivalent to the amount of buccal recession are marked in the interproximal papillae with a probe at the location of the intended new papillae tip (Video Clip 2).  Scalloped sulcular incisions are made with the new papillae tips formed from the existing papillae.  The incision is extended to the nearest line angle of the adjacent non-defect tooth.  At these line angles, oblique corono-apical releasing incisions are made (Video Clip 3).  Full thickness flaps are reflected to approximately 3 mm apical to the alveolar bone crest (Video Clip 4).  Starting at the coronal aspect, a split thickness flap is dissected to facilitate adequate mobility and coronal positioning of the flap (Video Clip 5).  The papillae are then deepithelialized to ensure a good vascular and connective tissue bed (Video Clip 6).

Rehydration of the acellular dermal graft material is essential for a minimum of 10 minutes.  Sterile saline or a tetracycline solution (250 mg tetracycline per 50 ml of sterile saline) is recommended.  The acellular dermal graft material is sized in the mouth.  The graft is then removed from the mouth and notched to fit the area (Video Clip 7).  The graft is adjusted to completely cover the defect and is positioned at the CEJ, while the inferior and lateral borders of the graft are extended at least 3.0 mm beyond the osseous defect margins.  The coronal border of the graft material is notched at the interproximal papillae to facilitate adequate blood flow between the papillae and the flap (Video Clip 8).  The graft is placed with the basement membrane side (smooth side) against the root surface (Video Clip 9) and is sutured using a sling suture technique with a Maxon^{® ££} suture (Video Clip 10).  This suture material is ideal because it is a monofilament with an extended resorption time of approximately 10 weeks.

Following anchoring of the graft material, the flap is coronally repositioned and sutured using a double sling suture technique.  Novafil^® suture material is used here because it is a nonresorbable monofilament with greater elasticity and excellent memory (Video 11).  The releasing incisions are closed with interrupted sutures using the Novafil^® suture material.

Recommended Post-Operative Protocol
The recommended post-operative protocol (Table 2) includes prescriptions for systemic doxycycline hyclate 50 mg once a day for 14 days to prevent plaque from colonizing the graft material to enhance optimal healing.¹⁵  Naproxen 375 mg every 12 hours for 7 days is used to control inflammation and swelling as well as post-operative pain.  If needed for severe pain, a narcotic analgesic of choice can also be given.  Starting the day of surgery when large areas (3 teeth or more) are treated, a tapered dose of dexamethasone, 3.0 mg q.d. for 3 days (three 1.0 mg tablets), 2.0 mg q.d. for 3 days (two 1.0 mg tablets), and 1.0 mg q.d. for 3 days (one 1.0 mg tablets) is given to reduce post-operative swelling.  It is important to prevent as much swelling as possible because clinical experience has shown that edema can disrupt graft stability and cause the sutures to pull through the papillae resulting in apical flap displacement.  Chlorhexidine digluconate 0.12% (CHX) mouthrinse should be applied twice daily with a cotton tip applicator for one month post-operatively for plaque control.  The CHX regimen should be continued until routine oral hygiene procedures can be resumed at approximately 1 month.  The patient is seen for weekly post-operative visits to evaluate healing and plaque control.  Sutures are not removed until the 1 month post-operative visit.  (3 mo. Post-Operative Video Clip)

£   Lifecore Biomedical, Inc., Chaska, Minnesota
££ Sherwood, Davis & Geck, D & G Monofil Inc., Manati, PA 00701
¶   Sherwood, Davis & Geck, D & G Monofil Inc., Manati, PA 00701

Click Here To Navigate Within Article >> ABSTRACT INTRODUCTION .....Advantages and Disadvantages of (ADG) Material .....Processing of the (ADG) Material .....Technique for Root Coverage Using (ADG) Material .....Recommended Post-Operative Protocol CASE 1 DESCRIPTION CASE 2 DESCRIPTION CASE 3 DESCRIPTION COMMENTS REFERENCES