Achieving excellence in anterior rehabilitations requires close cooperation between the periodontist and the prosthodontist. Many techniques can be used to restore the lost alveolar hard and soft tissues. The more severe the peri-implant defect, the higher the challenge and lower the predictability of the procedure. The present case consists of Seibert Class III with malaligned implants in the esthetic zone resolved with a cost-modified treatment plan to reestablish esthetics in the anterior maxilla using a rotated palatal flap. The vascularized interpositional periosteal connective tissue graft was effective in augmenting the soft tissue in the esthetic zone and remained stable over a 2-year period. Additional long-term clinical studies are necessary to support these results.

Introduction

Achieving dental implant esthetics in the anterior maxilla remains a challenge independent of the type of restoration.14  The prosthetic replacement of the missing tooth should be in harmony with the adjacent natural dentition to fulfill the patient's esthetic demand.5,6  However, in single tooth extractions, 50% of the width of the alveolar ridge is reduced in the first year postextraction, and in the first 3 months, most of the height is lost (approximately 1 mm).7,8  The majority of the remaining postextraction ridge defects are vertical and horizontal, classified as Seibert Class III.9  The selection of a surgical treatment depends on the type of anatomical defect and prosthetic treatment. When fixed single-unit crowns are planned in the esthetic zone, soft tissue augmentation may not be sufficient to solve the ridge defects. Seibert Class I or II defects may be resolved with connective tissue grafts alone; however, when the defect is severe, the traditional connective tissue grafts may have limitations.10,11  Seibert Class III defects may be addressed by surgical techniques that involve the use of a combination of soft and hard tissue grafts.9  Techniques used for Seibert Class III defects may include procedures conducted before or after implant placement with either hard or soft tissues or both.12  Management of ridge defects after implant placement are significantly more challenging as the number of walls of the defect reduces around the implant fixture.13 

In 1977, a palatal island flap,14  which was an epithelized connective tissue flap, was described. It was recommended for the late repair of oroantral communications that could eventually occur during extractions of the maxillary teeth or as a result of operations in the maxilla.

Advantages of using a vascularized palatal pedicle flap are its acceptable vascularization, excellent thickness and tissue bulk, and easy accessibility. It also allows for maintenance of the vestibular-sulcus depth.

Nemcovsky et al preconized the use of a split-thickness15  and full-thickness16  rotated palatal flap for primary closure after immediate implant placement. In addition, rotated pedicle flaps have been used for the purpose of soft tissue closure of grafted extraction sockets17  and closure of alveolar defects after bone grafting.18 

Advantages of the use of the vascularized interpositional periosteal-connective tissue (VIP-CT) graft are excellent blood supply, less morbidity, primary closure of donor and recipient bed, and patient acceptance due to donor and recipient site involving a single surgical site. In addition, it does not alter the color of the area.19  The literature does not show any contraindication for this technique; therefore, it would fall into a greater category of any surgical contraindication. Due to the success of the palatal pedicle flap technique, it was further used19  as a VIP-CT flap to optimize esthetics in dental implant rehabilitations.

The aim of this case report is to describe a multidisciplinary approach to managing the rehabilitation of a Seibert Class III defect in the esthetic zone using a VIP-CT graft20  and crown-lengthening techniques.

Case Report

A 47-year-old white woman reported the following chief complaint: “I want individual teeth. I don't want to cover my face when I smile.” The patient presented with a high lip-line upon forced smile. The clinical evaluation revealed a screw-retained procelain-fused-to-metal implant bridge from #7 to #8 with pink porcelain (Figure 1). The pink porcelain for implant #7 and #8 had a slightly darker shade, and crown #6 was larger compared with the contralateral tooth (Figure 1). The maxillary residual ridge was classified as Seibert Class III (Figure 2a). The ridge defect dimension at baseline was 20 mm mesiodistal, 10 mm high, and 8 mm wide. Clinical exam showed absence of exposed abutment cuff or dental implant threads. During probing, the periodontal probe did not seem to touch the threads, which were shown to be without osseous support in the radiographic exam (Figure 3). The probing depths (for mesial, midtooth, and distal) were the following for implants: #8 (buccal, 2, 3, 4; lingual, 3, 3, 5) and, #7 (buccal, 4, 3, 3; lingual, 4, 3, 3). There was absence of bleeding on probing on all 6 sites for implants #7 and #8. The radiographic exam showed presence of a moderate horizontal osseous defect between implants #8 (4.3 × 11 mm Replace Select, Nobel Biocare, Yorba Linda, Calif) and #7 (3.5 × 13 mm, Replace Select, Nobel Biocare). In addition, there were slight vertical defects in the mesial aspect of #8 and distal aspect of #7 (Figure 3). The patient reported absence of any systemic condition. She was diagnosed as ASA I, with bilateral Angle Class I relationship on canines and molars, acquired condition of mucogingival deformity localized to the ridge,21  horizontal and vertical deficiency peri-implants #7 and 8, and excessive gingival display of the maxillary left quadrant.

Figures 1–5

Figure 1. Frontal view of the high smile showing a screw-retained porcelain fused to metal implant bridge from #7 to #8 with pink porcelain. Note the unesthetic smile. Figure 2. (a) Frontal view of the ridge defect Seibert Class III with a template showing the ideal esthetic result. (b) Occlusal view of the maxillary ridge 2 at day of surgery. Patient was placed on cover screws 2 weeks preoperatively to allow creeping of the epithelium for better flap closure. Figure 3. Final periapical radiographic image showing moderate horizontal osseous defect between implants #8 (Nobel Biocare Replace select RP 4.3 × 11mm) and #7 (Nobel Biocare Replace select NP 3.5 × 13 mm. Note that the crown abutment is of a higher diameter than the implant platform diameter. This modification was required to reach an adequate emergence profile of the prosthetic crowns. Figure 4. Working models of the maxillary arch: (a) Note the wax-up made according to the #6, which required crown lengthening of the teeth #9 through #11 to obtain a harmonious smile line. (b) Note the dark shaded area of the cast, which is attributable to the lack of underlying tissues. Figure 5. Mock-up placed intraorally. Note the extensive ridge defect for implant #7 and #8.

Figures 1–5

Figure 1. Frontal view of the high smile showing a screw-retained porcelain fused to metal implant bridge from #7 to #8 with pink porcelain. Note the unesthetic smile. Figure 2. (a) Frontal view of the ridge defect Seibert Class III with a template showing the ideal esthetic result. (b) Occlusal view of the maxillary ridge 2 at day of surgery. Patient was placed on cover screws 2 weeks preoperatively to allow creeping of the epithelium for better flap closure. Figure 3. Final periapical radiographic image showing moderate horizontal osseous defect between implants #8 (Nobel Biocare Replace select RP 4.3 × 11mm) and #7 (Nobel Biocare Replace select NP 3.5 × 13 mm. Note that the crown abutment is of a higher diameter than the implant platform diameter. This modification was required to reach an adequate emergence profile of the prosthetic crowns. Figure 4. Working models of the maxillary arch: (a) Note the wax-up made according to the #6, which required crown lengthening of the teeth #9 through #11 to obtain a harmonious smile line. (b) Note the dark shaded area of the cast, which is attributable to the lack of underlying tissues. Figure 5. Mock-up placed intraorally. Note the extensive ridge defect for implant #7 and #8.

The patient was informed that the optimal treatment plan required implant removal, guided bone regeneration, and soft tissue graft procedures to reconstruct the ridge before planning for a new rehabilitation. The patient rejected removal of the implants and additional bone grafting. She indicated that she had been submitted to several procedures in the past and requested the most inexpensive procedure that would remove the “pink” from her prostheses. She also complained of difficulty performing her daily oral hygiene and requested individualized crowns to facilitate her oral hygiene regimen.

Working casts were prepared using an alginate impression of the maxillary and mandibular arches, and the casts were mounted in the articulator. The lost teeth were waxed up in order to reach a harmonious esthetic smile line. This required the teeth to be waxed up according to the height of tooth #6 (Figure 4). The wax-up showed the need to increase the height of crowns #9, #10, and #11 to reach an esthetic smile and reduce the excessive gingival display. For this purpose, crown lengthening was required. The patient's existing crowns #9 and #10 were re-prepped after establishing the ideal crown contours; provisionals were provided before the crown lengthening procedure. This procedure was conducted before the ridge augmentation procedure. A mock-up was made from bis-acrylic composite material for multiple-unit restorations (Protemp 4, 3M, Sumaré, São Paulo, SP, Brazil) and tested in the oral cavity (Figure 5). As shown in Figure 5, the ridge defect would need to be addressed even if the patient had chosen a conventional bridge from #6 through #9, with pontics for #7 and #8.

Provisionalization of implants #7 and #8 was conducted after crown lengthening (Figure 6). After crown lengthening, a new mock-up was made (Figure 7) to show the patient the possible position of the tissues after performing the VIP-CT graft20  procedure and fabricating crowns. The patient accepted the procedure, and a guide stent was fabricated by duplicating the mock-up in order for it to be placed immediately after the periodontal plastic surgery (Figure 8). The purpose of the guide stent is to guide the tissues postoperatively in order to help format the tissues during the healing phase.

Figures 6–11

Figure 6. Occlusal view of the screw-retained bridge for implants #7 and #8. Figure 7. Frontal view of the patient with second mock-up made 2 months after the crown-lengthening procedure. Note the harmonious esthetic smile line. Figure 8. The patient accepted the procedure, and provisional crowns were made for #7 and #8 for her to use before the surgery. Note extensively overcountered crowns for implants #7 and #8 due to the extensive ridge defect. Figure 9. Occlusal view of the maxillary arch. Note that papilla preserving incisions were made for distal aspect of #9 and mesial aspect of #6. Supracrestal incision is shown from #7 to #9. An “L” shape incision is present from the distal aspect of #13 to the mesial aspect of #9, approximately 3 mm from the sulcus of the teeth. Figure 10. Frontal view of the maxillary arch showing the vascularized interpositional periosteal connective tissue graft over implant #7 and #8 sites. Note the thickness of the flap and extension of the surgical site. Figure 11. (a) Occlusal view of the surgical site after the rotated palatal flap was positioned on the buccal aspect of implants #7 and #8. Note the increased width of the ridge. (b) Frontal view of the surgical site after cementation of the fixed provisional bridge from #6 through #9.

Figures 6–11

Figure 6. Occlusal view of the screw-retained bridge for implants #7 and #8. Figure 7. Frontal view of the patient with second mock-up made 2 months after the crown-lengthening procedure. Note the harmonious esthetic smile line. Figure 8. The patient accepted the procedure, and provisional crowns were made for #7 and #8 for her to use before the surgery. Note extensively overcountered crowns for implants #7 and #8 due to the extensive ridge defect. Figure 9. Occlusal view of the maxillary arch. Note that papilla preserving incisions were made for distal aspect of #9 and mesial aspect of #6. Supracrestal incision is shown from #7 to #9. An “L” shape incision is present from the distal aspect of #13 to the mesial aspect of #9, approximately 3 mm from the sulcus of the teeth. Figure 10. Frontal view of the maxillary arch showing the vascularized interpositional periosteal connective tissue graft over implant #7 and #8 sites. Note the thickness of the flap and extension of the surgical site. Figure 11. (a) Occlusal view of the surgical site after the rotated palatal flap was positioned on the buccal aspect of implants #7 and #8. Note the increased width of the ridge. (b) Frontal view of the surgical site after cementation of the fixed provisional bridge from #6 through #9.

Two weeks before the scheduled surgery, the crowns were removed and cover screws were placed to allow creeping of the epithelium for better flap closure. At the day of surgery, there was slightly more buccal gingival tissues around the cover screws for implants #7 and #8 (Figure 2b).

At the day of surgery, a horizontal incision was made parallel to teeth #9 through #13, approximately 3 mm from the sulcus of the teeth. Next, an intrasulcular incision was made on the palatal aspects of implants #7 and #8. Next, a midcrestal incision was made from the distal aspect of implant #7 to the mesial aspect of implant #8 (Figure 9). The VIP-CT graft20  was dissected from the palatal and rotated to the buccal aspect of implants #7 and #8 (Figure 10). Simple interrupted sutures (Figure 11a) were made using 4-0 Vicryl (polyglactin 910) thread, and a cement-retained provisional bridge was delivered (Figure 11b).

The healing process was uneventful. Twenty-one days postoperatively, note the excessive tissue on cervical aspect of the provisional bridge over implants #7 and #8 (Figure 12a). See the frontal view 2 months postoperatively (Figure 12b). A new cement-retained bridge was made for the patient for 2 reasons: (1) for tissue conditioning and (2) to simplify second-stage surgery, which was done with a simple intrasulcular incision on the soft tissues conditioned over the implants (Figure 13). The 5-month postoperative follow-up showed stability of the soft tissues with interproximal papilla between implants #8 and #7, which was not present at baseline (Figure 14). The 5-month impression taking was conducted to fabricate the final porcelain fused to zirconia IPS emax CAD lithium dissilicate crown (Ivoclari, Vivadent, Barueri, São Paulo, Brazil) for #6, #8, #9, #10, #11, and implants #7 and #8 (Figure 15a). Customized zirconia (IPS emax ZirCAD Ivoclair, Vivadent) abutments were made for implants #7 and #8 (Figure 15b).

Figures 12–15

Figure 12. Frontal view: (a) Twenty-one days postoperative. Note excessive tissue on the cervical aspect of the provisional bridge over implants #7 and #8. (b) Seventy-five days postoperative. A new set of provisionals was used to initiate gingival conditioning. Note that the tissues are less edematous. Figure 13. Frontal view 4 months postoperative. A new cement-retained bridge was made for the patient. Note that the tissues are less edematous compared with the 75-day postoperative clinical exam. Figure 14. (a) Frontal view at impression taking for final crowns 5 months postoperative. Note the presence of interproximal papilla for implants #7 and #8. (b) Absence of interproximal papilla in the buccal aspect of implants #7 and #8 at baseline. Figure 15. (a) Impression taking for fabrication of final porcelain fused to zirconia crowns for implants #7 and #8; and teeth #6, #9, #10, and #11. (b) Occlusal view after customized abutments were secured to implants #7 and #8. Note the thickness of the tissues on the buccal and palatal aspects.

Figures 12–15

Figure 12. Frontal view: (a) Twenty-one days postoperative. Note excessive tissue on the cervical aspect of the provisional bridge over implants #7 and #8. (b) Seventy-five days postoperative. A new set of provisionals was used to initiate gingival conditioning. Note that the tissues are less edematous. Figure 13. Frontal view 4 months postoperative. A new cement-retained bridge was made for the patient. Note that the tissues are less edematous compared with the 75-day postoperative clinical exam. Figure 14. (a) Frontal view at impression taking for final crowns 5 months postoperative. Note the presence of interproximal papilla for implants #7 and #8. (b) Absence of interproximal papilla in the buccal aspect of implants #7 and #8 at baseline. Figure 15. (a) Impression taking for fabrication of final porcelain fused to zirconia crowns for implants #7 and #8; and teeth #6, #9, #10, and #11. (b) Occlusal view after customized abutments were secured to implants #7 and #8. Note the thickness of the tissues on the buccal and palatal aspects.

The width of the buccal and palatal aspect of the restored ridge showed significant increase (Figure 16). The 2-year follow-up showed a more harmonious smile (Figure 16b) compared with baseline (Figure 16a). In spite of the fact that implant crown #7 and tooth crown #6 were larger crowns compared with crowns #9 and #10, the color of the gingiva was more homogenous compared with the contralateral site (Figure 17a). The 2-year follow-up showed stability of the soft tissues, and the patient indicated ease of performing oral hygiene regimen. The patient was also satisfied with the harmonious smile line (Figure 17). Periodontal tissues showed the following probing depths (for mesial, midtooth, and distal) for implants: #8 (buccal, 3, 3, 4; lingual, 3, 3, 5) and #7 (buccal, 4, 3, 3; lingual, 4, 3, 3). There was absence of bleeding on probing on all 6 sites for implants #7 and #8. Clinically there was absence of dental implant threads exposed. The patient's periodontal diagnosis was acquired condition of mucogingival deformity localized to the ridge21  with horizontal and vertical deficiency of peri-implants #7 and #8. The 2-year panoramic radiograph showed stability of the image suggestive of peri-implant osseous tissues (Figure 18).

Figures 16–18

Figure 16. (a) Two-year follow-up shows harmonious esthetics obtained using the vascularized interpositional periosteal connective tissue graft to restore the Seibert Class III alveolar ridge defect. (b) Frontal view at baseline with defective ridge and unesthetic prosthesis. Figure 17. (a) Lateral view of final crowns for implants #7 and #8. (b) Frontal view. Note the harmonious smile line. Figure 18. Panoramic radiograph showing stability of the peri-implant tissues.

Figures 16–18

Figure 16. (a) Two-year follow-up shows harmonious esthetics obtained using the vascularized interpositional periosteal connective tissue graft to restore the Seibert Class III alveolar ridge defect. (b) Frontal view at baseline with defective ridge and unesthetic prosthesis. Figure 17. (a) Lateral view of final crowns for implants #7 and #8. (b) Frontal view. Note the harmonious smile line. Figure 18. Panoramic radiograph showing stability of the peri-implant tissues.

Discussion

There is a high incidence of residual ridge defect following anterior tooth loss,7  which becomes an esthetic challenge of the anterior maxilla. In the present case, the patient presented with a ridge defect that required additional hard and soft tissue grafts. A challenge of this case was that the patient did not accept any procedure that would resolve the presented Seibert Class III defect, which included hard and soft tissue grafting, due to past experience of failed procedures and postoperative pain and discomfort. Patients who have suffered repeated unsuccessful ridge augmentation procedures encourage the clinician to consider alternative treatment options to bone grafts. The present case report shows the use of the VIP-CT20  graft for ridge augmentation to optimize the esthetics in the anterior maxilla with a successful esthetic final result at the 2-year follow-up.

The VIP-CT graft has its limitations, which include the difficulty to correct additional mucogingival defects in the same surgical procedure (eg, a shallow vestibule or a mucogingival line that is too near the crest of the alveolar ridge). In addition, there is absence of controlled studies that examined the long-term stability of localized ridge augmentation with soft tissues. Long-term controlled clinical trials are suggested to support the use of this technique to obtain the results shown in the current case. Another limitation of this case report was the inability to retrieve a periapical radiograph for comparison of baseline and 2-year evaluation of this patient due to address change.

During the surgical procedure, the implants were not treated chemically or physically. The implants were deep enough into the tissues and clinically did not show evidence of infection or inflammation that would indicate the need to conduct any disinfection or detoxification during the surgical procedure of VIP-CT grafting.

To provide the patient with an esthetic implant rehabilitation, the height and width of the residual ridge should allow placement of pontic or crown that appears to emerge from the ridge and mimic the appearance of the neighboring teeth. However, such residual ridge contours sometimes lead to unesthetic open gingival surfaces (black triangle), food impaction, and percolation of saliva during speech.22  The traditional connective tissue grafts may have its limitations to smaller ridge defects.10,11  The use of a vascularized palatal graft14,19  may increase the success of the technique. The present case report shows the rehabilitation of Seibert Class III using VIP-CT graft20  and crown lengthening to restore the esthetics in the anterior maxilla and facilitate oral hygiene in a 2-year follow-up.

Conclusion

The present case report shows the use of the VIP-CT graft as an acceptable alternative to esthetic challenges in cases of repetitive unsuccessful conventional hard and soft tissue grafting procedures for the resolution of mucogingival deformities and conditions around dental implants in the esthetic zone. The results in this case are limited to the 2-year follow-up. Additional long-term clinical studies are necessary to support these results.

Abbreviation

    Abbreviation
     
  • VIP-CT

    vascularized interpositional periosteal connective tissue

Acknowledgment

The authors would like to thank the Dental Laboratory Technician, Mr Ricardo Albino (Laboratório OPEN LAB, São Paulo, SP, Brazil), for fabricating the final crowns.

Note

The authors have no conflict of interest.

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