Atraumatic surgical extrusion using periotome in esthetic zone: A case series.

Several techniques have been proposed for clinical crown lengthening procedures. Crown lengthening in esthetic zone can be classified in two basic types: Restorative and non-restorative cases after the crown lengthening is executed. Atraumatic surgical extrusion using a specially designed instrument called periotome was performed in four cases on isolated teeth in esthetic zone. The technique presented is an alternative approach to periodontal surgical procedures consisting orthodontic extrusion and osseous recontouring. It does not result in functional or esthetic deformities especially in the anterior esthetic zone.

INTRODUCTION

Clinical crown lengthening refers to procedures designed to increase the extent of supragingival tooth structure for restorative or esthetic purposes.[1] The need for crown lengthening is dictated by dental and patient factors. Clinicians have to make the best treatment decisions by addressing the biological, functional, and esthetic requirements of every patient.[2]

When crown lengthening is planned to increase the length of affected available tooth, some biologic and anatomic considerations need to be considered and if not encroached upon this may lead to periodontal breakdown.[34] According to Gargiulo et al., the “biological width” varied in his histological study, but the average was 0.69 mm mean sulcus depth, 0.97 mm epithelial attachment and 1.07 mm for connective tissue attachment. This then totals 2.73 mm mean length of the dentogingival complex.[45]

Owing to the basic principle of biologic width, it has been proposed that there should be atleast 3 mm of supracrestal tooth tissue between the bone and the margin of the proposed restoration. The anatomical considerations that need to be considered when a patient is being assessed for crown lengthening are: Anatomy of the root (length and shape), furcation position; lip line (at rest and smiling); interdental bone width; soft and hard tissue anatomy and muscle insertions; width of attached gingival tissue.[56]

The indications of crown lengthening are:[78] Deep subgingival carious lesion; tooth fracture; to enhance retentive quality of restorations; endodontic perforations; root resorption-; unequal gingival levels; Esthetically short crowns; and altered passive eruption.

Clinical crown lengthening in esthetic zone can be classified mainly into restorative and non-restorative cases based on the need of restoration after crown lengthening. The treatment approaches differ significantly both in restorative and non-restorative cases.Although the procedures as shown in Table 1[91011] are extensively used, there are obvious disadvantages to each technique. Surgical crown lengthening by gingivectomy can be used only when there is a sufficient amount of keratinized tissue and hyperplasia of gingiva. The main disadvantage of the apically positioned flap surgery is its contraindication in the isolated esthetic zone. Repeated fiberotomy, necessity of retention phase after extrusion and the tendency to relapse are the main disadvantages of orthodontic extrusion.[911]

Table 1

The following are the clinical crown lengthening techniques in esthetic zone

In cases of deep subgingival carious lesion, subgingival tooth fractures and in cases where extensive osseous resective surgeries are contraindicated, the periotome extrusion procedure have been proposed with predictable esthetic and functional outcome.[812] Surgical extrusion by periotome technique also avoids the consequences of extensive resective surgery and orthodontic extrusion like uneven gingival margins, loss of interdental papilla, relapse and several fiberotomy sessions.[911]

The present case series reports four cases wherein atraumatic surgical extrusion technique was used for clinical crown lengthening in anterior esthetic zone with 2 years follow-up after surgical procedure to assess for bone formation in the extruded areas and to check for any esthetic or functional deformities induced by this procedure.

CASE REPORTS

Four-patients, between the age group of 25 and -35 years visited the Department of Periodontics, C.K.S. Teja Institute of Dental Sciences and Research, Tirupathi, Andhra Pradesh, India, with the chief complaint of “Short teeth” (fractured due to trauma and caries). Due to the loss of confidence and embarrassment within the society, these patients requested for any cosmetic therapy that would enhance the esthetics on smiling and during speech.

The patient's history revealed that the short teeth were due to trauma and carious lesion. Clinical examination revealed that the fracture of the teeth was due to accidental trauma and carious lesions with a healthy periodontium. Their medical history was non-contributory. The patients were in good general health and there were no contraindications for surgeries. After careful clinical and radiographic examination, the best suited patients were selected for clinical crown lengthening.

Considering the patients concern, (detailed information regarding periotome surgical extrusion, and the advantage of this technique over other procedures was explained to the patient) and the extrusion by periotome instrument reestablishes the new biologic width without any need of extensive resective surgery with pleasing final esthetics and overall reduction in treatment time, we decided the atraumatic surgical extrusion procedure in all the four patients.

Surgical procedure

Complete scaling and oral hygiene instructions advised 1 week prior to the surgical procedure. Antisepsis was carried out through aqueous solution of 0.12% chlorhexidine. After administering local anesthesia with 2% lidocaine, intrasulcular incisions were extended to each side of the adjacent teeth to raise a full thickness flap. All the granulation tissue was thoroughly debrided with area specific curettes.

Root canal treatment was done prior to surgical extrusion. After root canal treatment, coronal seal is obtained by composite restoration. There was no difficulty in obtaining a definitive coronal seal as the fracture margin was at gingival tissue.

The distance from the tooth fracture margin to the surrounding crest of alveolar bone was measured with William's graduated periodontal probe or UNC-15 probe (University of North Carolina) to calculate the amount of extrusions necessary. The blade of the periotome was placed in the periodontal ligament space of the tooth to be treated and manipulated in a “walking motion” to luxate the tooth. The tooth was carefully extruded to the desired position using a hemostat and placed at a level such that the fracture margin was situated atleast 3-5 mm from the alveolar crest. The simple interrupted sutures were employed for the closure of flaps.

Immobilization of the tooth can be achieved by interdental suturing and by the placement of a periodontal pack for 1 week. Although splinting is necessary, it is not advocated because splinting does not improve periodontal healing. Slight mobility during the periodontal healing period will be favorable for preventing resorption and ankylosis.

All the patients were instructed to rinse the mouth with 0.12% chlorhexidine for the following 2 weeks after surgery. Analgesics and antibiotics were prescribed post-operatively and the sutures were removed after 10 days. All the patients were recalled for checkup every 1 week for 1 month and then for every 1 month, up to 6 months post-operatively. Clinical and radiographic examinations were performed to assess changes in the bleeding on probing, mobility, periapical bone formation and percussion sounds of the tooth were noted during the recall visits.

After a 2-3 week post-surgery period, temporary crowns may be used until there has been full healing and the gingival margin is in a stable position. Patient referred to the restorative dentist for fixed prosthesis with zirconia crown after 6 months of surgical extrusion, only when there was no mobility, bleeding on probing and pocket depth clinically [Figures 1 and 2].

Figure 1

(a) Set of periotome instruments, (b) Severing the periodontal ligament by placing the periotome in periodontal ligament space, (c) Tooth is extruded by tissue forceps to the desired length, (d) 3 months post-operative view, (e) 6 months post-operative view with prosthesis

Figure 2

Radiographs (a) Pre-operative view, (b) During Root canal treatment, (c) 1 month post-operative, (d) 3 months postoperative, (e) 6 months post-operative, (f) 1 year post-operative, (g) 1 year and 6 months post-operative view

Periapical radiographs at 6 months, 1 year and 2 years shown radiopacity with new bone formation in the periapical area with normal periodontal ligament space. Radiographs did not show any crestal bone resorption in the post-operative radiographs by periotome extrusion technique.

Case 1

A healthy 29-year-old man with a horizontal fracture of the maxillary right lateral incisor was referred to the Department of Periodontics, for a clinical crown lengthening procedure. On clinical examination, the involved tooth was fractured at the level of interdental papilla. After administering local anesthesia, the tooth was extruded with the help of periotome and the fractured margin was placed approximately 5 mm above the level of the marginal gingiva.

An increase in radiographic density suggesting the new bone formation was observed around the periapical area at the 3-month post-operative examination and there was no mobility and any root reorption. Permanent crown was given at 6 months after the surgery.

Case 2

A 35-year-old, non-smoker with a horizontal fracture of the maxillary left central incisor referred to the Department of Periodontics by prosthodontist for clinical crown lengthening. The involved tooth was in a submerged state, and the clinical and radiographic evaluation revealed a fractured tooth margin below crestal bone. The decision was made to perform surgical extrusion for clinical crown lengthening and subsequent crown replacement. The tooth was extruded and placed at a level such that the fracture margin was situated at least 3 mm from the bone crest.

Tooth mobility and gingival inflammation decreased gradually during the 2nd week of post-operative recall. After 3 and 6 months follow-up, there was mere absence of tooth mobility and inflammation. Patient was given a fixed crown after the complete reduction of tooth mobility clinically.

Case 3

A 26-year-old patient, gave a history of trauma (bike accident) 3 weeks back and he had not visited for any dental treatment before he visited Department of Periodontics for clinical crown lengthening in relation to maxillary central incisors. Careful clinical and radiographic evaluations were performed prior to the surgical procedure for the sake of case selection. Mild and continuous types of pain were experienced by the patient over the past 3 weeks.

On intraoral examination, there was tenderness on percussion and gingivitis with no mobility in relation to 11 and 21. Radiographic examination revealed no periapical pathology. Both 11 and 21 were vital with heat and cold tests.

Root canal treatment was done prior to surgical extrusion. After root canal treatment in relation to 11 and 21, coronal seal is obtained by composite restoration. There was no difficulty in obtaining a definitive coronal seal as the fracture margin was at gingival tissue. Patient was given a fixed crown after the complete reduction of tooth mobility clinically after s 6 months.

Case 4

A 25-year-old patient, referred for crown lengthening in relation to maxillary left central incisor due to the insufficient clinical crown height for a restorative purpose. On thorough clinical and radiographic survey, we decided to go for surgical extrusion by specially designed periotome instrument.

The tooth was endodontically treated and routine oral prophylaxis was carried out prior to the surgical extrusion. The tooth was extruded and placed at a level such that the fracture margin was situated at least 5 mm from the bone crest. After 1 month post-operative period, there was minimal gingival inflammation, tooth mobility and there was increase in bone density in the periapical area. After 6 months post-operative period there was no bleeding on probing and mobility clinically and there was complete new bone formation in the periapical area, which helps the tooth to function normally and the patient was referred to the Department of Conservative Dentistry for restorative phase. Thus with this treatment regime final esthetics was maintained.

DISCUSSION

Clinical crown lengthening in the esthetic areas requires a more elaborate and sophisticated diagnostic process, and treatment modality selection.[1314155] When choosing surgical crown lengthening in the esthetic zone extreme care should be taken because it will often result in asymmetry of the gingival line[141617] . The most likely specialist to perform crown lengthening procedure has been shown to be a Periodontist, who plays a key role in the clinical crown lengthening.[1718]

Several techniques have been proposed for clinical crown lengthening procedures.[1819] Particularly in the anterior esthetic regions, the preservation of gingival margin and interdental papilla is required in order to obtain satisfactory final esthetic outcome.[2021]

To overcome the disadvantages of resective osseous surgery and orthodontic extrusion, like loss of papillae, uneven gingival margins, poor crown root ratio and the need for several fiberotomy sessions and relapse tendency, we decided to use a specially designed periotome surgical extrusion technique in the anterior esthetic zone.[91022]

Surgical extrusion by many authors was done by ostectomy at the root apex and pushing the root apex until the desired position is achieved. Following extrusion, bone graft should be placed to achieve stability. Tooth luxation was first performed by Khanberg. He introduced careful and gentle luxation of the tooth until desired position is achieved. Khanberg technique advocates only root luxation until the desired position is required without any ostectomy and use of bone grafts at root apex when compared to other transplantation techniques. Whereas periotome technique uses a specialized instrument, which easily luxates the tooth by severing the periodontal ligament and also has the advantage of not disturbing the alvelolar crest margin as in case of other luxation techniques.

Periotome is a specially designed instrument for atraumatic extrusion and the technique has the advantages of minimizing the risk of dehydration of periodontal ligament and the root never extruded out of the socket during the entire surgical procedure. Hence, the healing pattern is normal as the vitality of the periodontal ligament and the cementblastic layer is maintained. It helps in preventing resorption and ankylosis during and after the follow-up period. The basic principle of surgical extrusion technique is to place the affected tooth structure in a more desired position, which helps in reestablishment of biologic width.[11232425]

Table 2 describes the advantages and disadvantages of surgical extrusion, periotome extrusion, orthodontic extrusion, intentional replantation and gingivectomy/ostioplasty/odontoplasty. Table 2 highlights the possible advantages of periotome extrusion over intentional replantation.

Table 2

Advantages and disadvantages of various crown lengthening procedures

CONCLUSION

One of the best advantages of the surgical extrusion by periotome technique is the reduction of the overall treatment time when compared to orthodontic extrusion technique. Periotome surgical extrusion is more conservative in the maintenance of bone architecture when compared with osseous resection. The proposed technique in these case reports is an alternative to osseous resection and orthodontic tooth extrusion.

Thus, this technique can be used successfully to treat a severely damaged tooth, especially in the anterior esthetic zone.