A sequential approach in treatment of perio-endo lesion.

The success of a combined periodontal and endodontic lesion depends on the elimination of both of these disease processes. In the case of a combined endo-perio lesion, the endodontic therapy results in healing of the endodontic component of involvement while the prognosis of tooth would finally depend on the healing of the periodontal structures. This case report evaluates the efficacy of bioactive glass in the management of furcation defect associated with an endo-perio lesion in a right mandibular first molar. A 22-year-old male patient with an endo-perio lesion in the right mandibular first molar was initially treated with endodontic therapy. Following the endodontic treatment, the furcation defect was treated using bioactive glass in a putty form. At the end of 9 months, there was a gain in the clinical attachment level and reduction in probing depth. Radiographic evidence showed that there was a significant bony fill.

INTRODUCTION

The relationship between pulp of the tooth and surrounding periodontium was first described in 1964[1], and since then the term endo-perio has become an integral part of the dental vocabulary. Unfortunately, this term has been used indiscriminately to categorize disease of either periodontal or endodontic etiology, with or without secondary involvement of the other. It conveniently provides a blanket diagnosis but could be misleading for any such lesion, regardless of its primary etiology.

Furcation involvement presents one of the major challenges in endodontic therapy with periodontal involvement. Although the role of pulpal pathology in the etiology of furcation involvement is still unclear, the high incidence of molar teeth with accessory canals supports such an association.

Various treatment modalities[2] have been proposed for the treatment of furcation involvement alone including open flap debridement, bio-modification of root surface, and various regenerative procedures including GTR and bone grafts. Bone grafts having a property of osteogenesis, osteoinduction, and osteoconduction have been used in the past.

A new property of osteostimulation[3] has been reported in some recently available materials. This case report attempts to utilize a bioactive glass with the property of osteostimulation as bone replacement graft in the treatment of a combined endo-perio lesion with furcation involvement.

Relationship between pulp and periodontium

Pulpal and periodontal problems are responsible for more than 50% of tooth mortality. The periodontium and pulp have embryonic, anatomic, and functional interrelationship. The relationship between pulpal and periodontal disease can be traced to embryological development, since the pulp and the periodontium are derived from a common mesodermal source.[4] At the stage of tooth development, the developing tooth bud pinches off a portion of mesoderm that becomes pulp, while the remaining mesoderm develops into the periodontium. Ectomesenchymal cells proliferate to form the dental papilla and follicle, which are the precursors of the periodontium and the pulp, respectively. This embryonic development may give rise to an anatomical connection between these two vital structures throughout the life of a tooth. Three main pathways[4] have been implicated in the development of periodontal-endodontic lesions, namely:

Dentinal tubules

Lateral and accessory canals

Apical foramen

Classification

The most commonly used classification was given by Simon et al.[5]

Primary endodontic lesion

Primary periodontal lesion

Primary endodontic lesion with secondary periodontal involvement

Primary periodontal lesion with secondary endodontic involvement

True combined lesion

CASE REPORT

A 22-year-old patient reported to the Department of Periodontics with a complaint of pain in the lower right back tooth region associated with pus discharge since 1 month. On intraoral examination, an intraoral sinus was found to be present in relation with 46 [Figure 1]. A radiograph was taken with a gutta percha cone inserted in the sinus so as to gauge the path of the sinus tract as shown in Figure 2. It was found that the sinus was associated with the mesial root of 46. IOPA also showed widening of periodontal ligament space in relation with the mesial root and radiolucency in the furcation area. The horizontal probing depth (HPD) with Naber's probe and vertical probing depth (VPD) with the UNC-15 probe were measured which were found to be 6 mm and 4 mm, respectively. Probing was standardized by fabricating an acrylic stent as shown in Figures 1 and 3. The patient was then referred to department of conservative dentistry to check for tooth vitality. Electric pulp testing was done to check for tooth vitality, which confirmed that the tooth was nonvital.

Figure 1

VPD of 4 mm with UNC-15 probe

Figure 2

Radiograph showing gutta percha when inserted though the sinus tract extending till the mesial root of 46

Figure 3

HPD of 6 mm with Naber's Probe

Treatment planning was done taking into consideration that the tooth was nonvital with a prevailing sinus tract and grade II furcation involvement as well.

Endodontic treatment was taken up first and the patient was followed up for 3 months. At the end of third month, IOPA was taken with 46 which showed that the furcation involvement still prevailed [Figure 4]. On clinical examination, it was observed that there was no change in the soft tissue measurements. Therefore, periodontal regenerative surgery using dental putty was planned for treatment of furcation defect [Figure 5 and 6].

Figure 4

Obturated 46 with radiolucency still evident after 3 month

Figure 5

Furcation defect with 46

Figure 6

Graft material in place at the defect

Surgical procedure

After taking care of asepsis and sterilization the surgery was planned. The area selected for surgery was anesthetized using xylocaine with adrenaline 1:200,000. A full thickness flap was raised at the buccal aspect following intracrevicular incision and vertical releasing incision. A vertical releasing incision was placed extending into the alveolar mucosa not closer than one tooth to the involved area, i.e. 46. Full thickness flap was raised till the base of furcation defect followed by split thickness flap beyond the mucogingival junction. This was done so as to facilitate the coronal positioning of flap, there by resulting in complete coverage of the defect and the material used. After reflection thorough degranulation and debridement was done at the defect area using Gracey's curette # 13 and 14. Also thorough scaling and root planning was carried out on the exposed root surface area of the defect.

Dental putty graft material with osteoconductive and osteostimulative properties was placed and stabilized in the furcation area. Primary soft tissue closure of the flap was done with nonresorbable black silk (3–0) suture using interrupted suturing technique [Figure 7].

Figure 7

Immediate postoperative

Post-op instructions

The patient was advised proper plaque control, and was prescribed 0.12% chlorhexidine mouthwash for rinsing twice daily. The sutures were removed 10 days after surgery and the patient was advised to brush at the surgical site using a postsurgical brush for 2 weeks. The patient was also advised to continue mouthwash for another 3 weeks.

The patient was put on regular recall at 1, 3, 6, and 9 months. A bioactive glass resulted in a substantial amount of bone fill in the furcation. After 9 months, the probing depth was found to reduce by 3 mm. The post-op radiograph shows bone fill in the furcation defect as shown in Figure 8.

Figure 8

Radiograph showing restored 46 with bone regeneration in the furcation area

DISCUSSION

When a clinician cannot make a definitive diagnosis in the case of an endo-perio lesions, it may be prudent for him or her to initiate either of the treatment modalities and hope for repair. However, this could be overcome by proper history taking and sequential treatment planning.

When the etiology is purely endodontic, calcium hydroxide can be used as an intracanal medicament. It is an excellent medicament in general, because it is bactericidal, anti-inflammatory and proteolytic; it inhibits resorption; and it favors repair. It is especially effective in endodontic lesions with extensive periapical pathology and pseudo pockets, because of its temporary obturating action which would inhibit periodontal contamination of the instrumented canals via patent channels of communication. This regimen usually will resolve the pseudo pocket within a few weeks.

However, lesions which are not true combined lesions, little or no improvement would be seen with the periodontal perspective after endodontic treatment, leaving a very poor and often hopeless prognosis. But with the advent of new regenerative materials, however, successful periodontal treatment of such lesions has been possible.

In this report the pulp vitality test which showed the nonvital nature of the tooth was a pivoting finding suggesting the primary endodontic involvement. Generally, in a case of combined endo-perio lesion, an adequate endodontic therapy would result in healing of the endodontic component, and the prognosis would finally depend on the efficacy of periodontal repair/regeneration initiated by either of the treatment procedures. In this case, following endodontic treatment the periodontal lesion did reduce to an extent on radiographic evaluation after 3 months but did not subside completely with no change in the clinical parameters. This confirmed a secondary periodontal involvement along with primary endodontic component.

Clinical studies with bioactive glass particulate have been gaining momentum in recent scenario. Bioactive glass shows both osteoconductive and osteostimulatory effects. The pore size (90–710 μm) allows optimal space for vascularization. It enhances bone formation by ionic dissolution of the ceramic particles such that the silica gel layer forms over the particles on contact with body fluids. Over this silica gel layer, a calcium phosphate layer forms, which is quickly converted into a hydroxycarbonate apatite layer. This apatite layer has been shown to be identical to bone mineral and to provide the surface for osteoblast cell attachment and bone deposition.[6]

The results of this case report suggest that bioactive glass in the form of putty resulted in a significant amount of bone fill and reduction in HPD. This was in accordance with the studies by Yukna et al.[7] and Anderegg et al.[8] Also studies by Raja et al.[9] and Humagain et al.[10] using bioactive glass showed significant improvement in the clinical parameters when used in furcation defects.

CONCLUSION

The healing of an endodontic lesion is highly predictable, but the repair or regeneration of periodontal tissues is questionable if associated with it. Endodontic therapy mostly should precede periodontal pocket elimination procedures in the case of a primary endo and secondary periodontal involvement; however, endodontic therapy would result only in resolution of the endodontic component of involvement and would have a little effect on the periodontal lesion.[9] Therefore a thorough diagnostic examination usually will indicate the primary etiology and, thereby, direct the proper course of treatment plan as presented in this case.

It could also be concluded that bioactive glass in the form of putty which was primarily due to 21% of glycerin added to 69% of bioactive glass and 10% of poly ethylene glycol, made it feasible for manipulation of the material and effective defect fill. Therefore within the limits of this study it can be concluded that bioactive glass is effective as a bone graft substitute in treatment of periodontal component of the endodontic lesion.