Treatment of Biologic Width Invasion and Apical Periodontitis: A Single-Stage Combined Approach

INTRODUCTION
The surgical extrusion technique has proven to be an alternative choice for re-establishing biologic width.^1-4 As a treatment procedure, it is fairly easy to perform, reducing the time until prosthetic resolution, while eliciting low root resorption and ankylosis rates.⁵ The maintenance of the supporting and protecting periodontal tissues makes this technique an alternative approach, within the domain of periodontal therapy, to the subgingival tooth fracture, deep caries, root perforations in the cervical third, and all tooth involvements that violate the biologic width.2 This technique permits the direct inspection of the root, enabling the presence of any such cracks to be detected, and offers to a practitioner who has visually examined the root, easing the decision regarding the most suitable course of treatment, and thereby improving prognosis. Similarly, the intentional replantation has been an alternative management for cases in which intracanal and surgical endodontic treatments are not recommended.^6-8 The success of these procedures is dependent upon a minimally traumatic extraction and short extraoral time for maintaining the vital periodontal ligament and cementum, and to prevent root resorption.^5,9-11

The present case report describes a single-stage combined approach involving endodontic treatment, surgical extrusion, and socket debridement for the reestablishment of biologic width and periapical healing.

CASE REPORT
Diagnosis and Treatment Planning
A healthy 35-year-old white woman presented with a severe tooth destruction of the right second mandibular premolar and missing the first molar (Figures 1 and 2). No periodontal disease and no painful symptomatology were evident. The radiographic image depicted a biologic width that was compromised by the subgingival root remnant due to caries. No previous endodontic treatment and discreet root resorption at the apex were seen associated with the radiolucent periapical lesion (Figure 3). Nevertheless, the patient sought to restore proper function and appearance to the premolar.

Figure 1. Preoperative photo, showing severe tooth destruction and normal gingival tissue of the right second mandibular premolar.	Figure 2. Extensive caries and biological width invasion of the right second mandibular premolar were evident.
Figure 3. Preoperative radiograph, showing no endodontic treatment and periapical lesion of the right second mandibular premolar.	Figure 4. The avulsed premolar showing the overfilled gutta-percha points. Note the presence of periodontal ligament remnants on the root.

The patient was informed about the treatment options, such as endodontic treatment associated to the surgical crown lengthening with osteotomy or orthodontic extrusion, a single-stage combined approach involving endodontic treatment, or surgical extrusion and socket debridement. The advantages and disadvantages of the treatment options were explained to the patient.

With the patient’s consent, a single-stage combined approach was planned. This option was chosen due to the reduced treatment time, but also to preserve the attachment level.

Treatment Protocol
After basic periodontal treatment, a proper endodontic treatment was performed with root canal sealer (AH plus [DENTSPLY DeTrey]) and gutta-percha points (Gutta Percha Points [DENTSPLY]) using the lateral compaction technique. Overfilling of the obturation material was purposely achieved. Under local anesthesia, the surgical extrusion was then performed, as previously described.² The initial incision was made using a sharp No. 15 C blade, followed by gentle luxation with a periotome and tooth avulsion using pedodontic forceps. Care was taken during the surgical procedure so no bone loss would occur. The avulsed tooth was inspected under the surgical microscope for root fractures, and excess material extruding beyond the apical foramen was then removed with surgical scissors. The periodontal ligament adjacent to the root was kept intact and not manipulated (Figure 4). Before tooth replantation, meticulous socket debridement was performed using a surgical spoon curette. The stabilization of the root in the new desired position (3 mm coronally out of the socket) was accomplished by use of an interdental suture (4.0 Vicryl [Ethicon]) and splints. A surgical dressing was not applied over the root (Figure 5). The patient received routine postsurgical instructions to use a 0.12% chlorhexidine mouthrinse (Periogard [Colgate-Palmolive]) twice daily; and 400 mg ibuprofen, 3 times daily for 2 days.

Two months later, the periodontal ligament was consistent with a healthy functional state and the supra-alveolar root surface, allowing room for biologic width reconstruction, was noted (Figure 6). For this, a conventional cast metal alloy post and core and definitive metal-ceramic crown were fabricated and cemented with a zinc phosphate cement. During the follow-up visit (one year later), a stable crown position with good function and healthy gingival tissue were observed (Figure 7). The radiographic evaluation showed a functional periodontal ligament and healing of the radiolucent periapical lesion, with no signs of resorption or ankylosis (Figure 8).

Figure 5. Occlusal view of the coronally positioned root and tightly performed interproximal sutures used to achieve tooth stability.	Figure 6. Radiograph at 2 months after surgery, displaying the integrity of the alveolar bone crest and re-establishment of the periodontal ligament.
Figure 7. Postoperative buccal view at one year of the definitive restoration on the right second mandibular premolar.	Figure 8. Radiograph at one year after final restoration.

DISCUSSION
The basic principle of the surgical extrusion is to move the affected tooth area to a supragingival position, leaving sound tooth structure exposed supra-alveolarly and providing room for the reestablishment of the biologic width. Previous reports have confirmed the successful management of the surgical extrusion technique.^1-4 The present single-stage combined approach was more beneficial regarding the number of required procedures and it was a relatively easy treatment that has shortened the time until the prosthetic solution. However, the disadvantages of the surgical extrusion could be related to the risk for root fracture during the surgical management and root resorption. The fracture risk was eliminated by careful surgical handling, and the risk of root resorption was reduced by preserving the vitality of the periodontal ligament, which is reported to be a critical factor for preventing root resorption and ankylosis after replantation.^9-11 Moreover, to reduce the risk of root resorption, splinting was not performed. Root movement in the socket can play an important role in preventing the ankylosis process.^12-14 Recently, the experimental study in dogs showed that the surgical extrusion elicited low root resorption and ankylosis rates. The different areas of resorption observed did not cause sufficient morphologic/functional damage and all the resorption gaps presented were repaired by new cementum and a new functional periodontal ligament.⁵ Nevertheless, the final restoration promoted great satisfaction from the patient, and one-year monitoring shows the ability of the periodontium to adapt function, aesthetic recovery, and periapical healing.

CONCLUSION
A single-stage combined approach involving endodontic treatment, surgical extrusion, and socket debridement can be a useful means of successfully treating teeth with an invasion of biologic width and apical periodontitis, and this technique may allow a reduction in treatment time.

References

1. Kahnberg KE. Intra-alveolar transplantation. I. A 10-year follow-up of a method for surgical extrusion of root fractured teeth. Swed Dent J. 1996;20:165-172.
2. Kim SH, Tramontina V, Passanezi E. A new approach using the surgical extrusion procedure as an alternative for the reestablishment of biologic width. Int J Periodontics Restorative Dent. 2004;24:39-45.
3. Kim CS, Choi SH, Chai JK, et al. Surgical extrusion technique for clinical crown lengthening: report of three cases. Int J Periodontics Restorative Dent. 2004;24:412-421.
4. Chung MP, Wang SS, Chen CP, et al. Management of crown-root fracture tooth by intra-alveolar transplantation with 180-degree rotation and suture fixation. Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2010;109:e126-e130.
5. Kim SH, Tramontina VA, Ramos CM, et al. Experimental surgical and orthodontic extrusion of teeth in dogs. Int J Periodontics Restorative Dent. 2009;29:435-443.
6. Cotter MR, Panzarino J. Intentional replantation: a case report. J Endod. 2006;32:579-582.
7. Herrera H, Leonardo MR, Herrera H, et al. Intentional replantation of a mandibular molar: case report and 14-year follow-up. Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2006;102:e85-e87.
8. Sivolella S, Bressan E, Mirabal V, et al. Extraoral endodontic treatment, odontotomy and intentional replantation of a double maxillary lateral permanent incisor: case report and 6-year follow-up. Int Endod J. 2008;41:538-546.
9. Andreasen JO, Borum MK, Jacobsen HL, et al. Replantation of 400 avulsed permanent incisors. 4. Factors related to periodontal ligament healing. Endod Dent Traumatol. 1995;11:76-89.
10. Mclntyre JD, Lee JY, Trope M, et al. Management of avulsed permanent incisors: a comprehensive update. Pediatr Dent. 2007;29:56-63.
11. Trope M. Avulsion of permanent teeth: theory to practice. Dent Traumatol. 2011;27:281-294.
12. Andersson L, Lindskog S, Blomlöf L, et al. Effect of masticatory stimulation on dentoalveolar ankylosis after experimental tooth replantation. Endod Dent Traumatol. 1985;1:13-16.
13. Mine K, Kanno Z, Muramoto T, et al. Occlusal forces promote periodontal healing of transplanted teeth and prevent dentoalveolar ankylosis: an experimental study in rats. Angle Orthod. 2005;75:637-644.
14. Barros I, Muramoto T, Soma K. Effects of occlusal loading on alveolar bone remodeling and changes in the distribution of neuropeptides after tooth replantation in rats. J Med Dent Sci. 2007;54:49-56.

Dr. Sung Hyun Kim works in the department of periodontology at the Pontifical Catholic University of Parana, School of Dentistry, in Curitiba, Brazil. He can be reached via e-mail at sung.kim@pucpr.br.

Dr. Tramontina works in the department of periodontology at the Pontifical Catholic University of Parana, School of Dentistry, in Curitiba, Brazil. He can be reached at vinicius.tramontina@pucpr.br.

Dr. Luczyszyn works in the department of periodontology at the Pontifical Catholic University of Parana, School of Dentistry, in Curitiba, Brazil. She can be reached at sonia.luczyszyn@pucpr.br.

Dr. Papalexiou works in the department of periodontology at the Pontifical Catholic University of Parana, School of Dentistry, in Curitiba, Brazil. She can be reached at vula.papalexiou@pucpr.br.

Dr. Pâmela Kim works in the department of endodontology at the Pontifical Catholic University of Parana, School of Dentistry, in Curitiba, Brazil. She can be reached at kim.pamela@hotmail.com.

Dr. da Silveira Neto works in the department of endodontology at the Pontifical Catholic University of Parana, School of Dentistry, in Curitiba, Brazil. He can be reached via e-mail at ulix@terra.com.br.

Disclosures: The authors report no disclosures.