Ridge Augmentation by Guided Bone Regeneration Technique

Journal of Dental Sciences and Oral Rehabilitation, April-June 2014;5(2):99-102 99

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Ridge Augmentation by Guided Bone Regeneration Technique1Kausar Parwez Khan, 2Shankar T Gokhale, 3Mohd Amjad Tahseen, 4Sidharth Shankar, 5Garima Singh, 6Priya Saxena

ABSTRACTResorption of the edentulous or partially edentulous alveolar ridge or bone loss due to periodontitis or trauma frequently com­promises­fixed­prosthesis­placement.­Therefore,­augmen­tation­of­an­insufficient­bone­volume­is­often­indicated­to­attain­predictable­ long­term­ functioning­ and­ an­ esthetic­ treatment­outcome.­Guided­bone­regeneration­ (GBR)­ techniques­have­been used for vertical and horizontal ridge augmentations with accep­table­results.­The­principle­of­guided­bone­regeneration­can be applied for localized ridge augmentation in a staged app­roach.­The­technique­is­based­on­the­principle­of­guided­bone­regeneration­utilizing­barrier­membranes.­In­the­present­article,­the­GBR­surgical­procedure­is­presented.­In­addition,­the­different aspects of the surgical technique needed to achieve a predictable­success­are­also­discussed.

Keywords: Guided­bone­regeneration,­Guided­tissue­rege­ne­ration,­Ridge­augmentation,­Bone­graft,­Membrane.

How to cite this article: Khan­KP,­Gokhale­ ST,­Tahseen­MA,­Shankar­S,­Singh­G,­Saxena­P.­Ridge­Augmentation­by­Guided­Bone­Regeneration­Technique.­J­Dent­Sci­Oral­Rehab­2014;5(2):99­102.

Source of support: Nil

Conflict of interest: None

INTRODUCTION

Resorption of alveolar bone following loss of teeth is an inevi table outcome. In cases with trauma or congenital defects, this resorption is further increased. The term ‘loca­lized alveolar ridge defect’ refers to volumetric deficit of bone and soft tissue within the alveolar process. The most commonly used classification for ridge defect is the Seibert’s nomen clature. Another classification was given by Allen that classifies the defects from Type A to Type C (Table 1).1,2

Various techniques for ridge augmentation include distra c tion osteogenesis, guided bone regeneration and piezo surgery. The distraction osteogenesis and piezosurgical tech ni ques are more invasive techniques compared to guided

CASE REPORT

1,3­6Postgraduate­Student,­2Professor1­6Department­of­Periodontology­and­Implantology,­Institute­of­Dental­Sciences,­Bareilly,­Uttar­Pradesh,­India

Corresponding Author:­ Kausar­Parwez­Khan,­Postgraduate­Student,­Department­of­Periodontology­and­Implantology,­Institute­of­Dental­Sciences,­Bareilly,­Uttar­Pradesh,­India,­e­mail:­kausar­5983@gmail.com

10.5005/jp-journals-10039-1022

bone regeneration (GBR) procedure. Guided bone regenera­tion is based on principles of guided tissue regeneration3

(GTR). Guided tissue regeneration was first developed in the early 1980s by Nyman et al.3 Melcher described the concept of selective cell repopulation of defects to enhance healing.4

Exclusion of fast­growing epithelium and connec tive tissue from a periodontal wound for 6 to 8 weeks allows the slower growing tissues, including osteoblasts, cementoblasts and perio dontal ligament cells occupy the space adjacent to the tooth.3,5 Guided bone regeneration concept employed the same principles of specific tissue exclusion but was not asso ciated with teeth. Thus, the term applied to this tech­nique was GBR. This case report presents GBR proce dure for management of alveolar ridge defects and its out come after 6 months.

Principles of Guided Bone Regeneration6

To achieve better clinical outcomes, the GBR barrier should possess the following properties:

Cell Exclusion

In GBR, the barrier membrane is used to prevent gingival fibroblasts and/or epithelial cells from gaining access to the wound site and forming fibrous connective tissue.

Tenting

The membrane is carefully fitted and applied in such a man­ner that a space is created beneath the membrane, completely isolating the defect to be regenerated from the overlying soft tissue.

Scaffolding

This tented space initially becomes occupied by a fibrin clot, which serves as a scaffold for the ingrowth of progenitor cells. In GBR, the cells will come from adjacent bone or bone marrow.

Stabilization

The membrane must also protect the clot from being disturbed by movement of the overlying flap during healing. It is therefore often, but not always, fixed into position with sutures or mini bone screws.

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Framework

Where necessary, as in nonspace maintaining defects, such as dehiscence or fenestration, the membrane must be supported to prevent collapse.

CASE REPORT

An 18-year-old boy reported to the department of perio-dontics with the chief complaint of replacement of upper left front tooth. The patient gave the history of trauma 6 months back following that the tooth got avulsed. The patient was systemically healthy. On intraoral examination, upper left central incisor was found missing and ridge deficiency was also seen in the same region (Fig. 1). Ridge defect was

combined horizontal and vertical (Seibert’s Class III).The 2-dimensional periapical radiograph of the patient showed that there was association of osseous defect comprising of differential bone loss in the same region (Fig. 2).

Later, comprehensive treatment plan was done, after 4 weeks of completion of phase I therapy, the case was scheduled for surgical procedure in anticipation of ridge augmen tation. Full thickness flap was raised by giving crestal incision in the region of the missing tooth 21 and continued by giving sulcular incision to the adjacent teeth for proper accessibility (Fig. 3). After complete debridement and isolation, defect was found to be of both horizontal and vertical pattern falling under Siebert’s Class III classifica­tion of volumetric deficit of bone and soft tissue within the alveolar process (Fig. 3). An AlloplastBioGraft bone graft was placed into defect and care was taken not to overfill the defect and over the grafted area, resorbable guided tissue regeneration membrane (Periocol GTR) was stabi­lized by giving periosteal suturing (Figs 4 and 5). Finally flap was closed by simple interrupted sutures and perio-dontal dressing Coe-Pak was given over the surgical site (Figs 6 and 7). Postoperative instructions were given and

Fig. 1: Preoperative image showing ridge defect in 21 region

Table 1:­Seibert’s­and­Allen’s­classification­of­ridge­defects

Criteria for classification Seibert’s nomenclature

Allen’s nomenclature

Horizontal or buccal tissue loss with normal ridge height

Class­I Type­B

Vertical tissue loss with normal ridge height

Class­II Type­A

Combined horizontal and vertical bone loss

Class­III Type­C

Fig. 2: Preoperative IOPAR of 21 region

Fig. 3: Mucoperiosteal flap reflection showing ridge defect Fig. 4: Placement of bone graft (BioGraft HA)

Ridge Augmentation by Guided Bone Regeneration Technique

Journal of Dental Sciences and Oral Rehabilitation, April-June 2014;5(2):99-102 101

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Fig. 5: Placement of GTR membrane Fig. 6: Placement of suture

Fig. 7: Periodontal dressing placed Fig. 8: Postoperative view after 1 week

Fig. 9: Postoperative view after 6 months Fig. 10: Radiographic view after 6 months of surgery

also adviced Amoxicillin (500 mg), three times daily for 5 days, and Ibuprofen (400 mg) thrice daily was prescribed for 3 days along with 10 ml of chlorhexidine (0.2%) mouthwash twice daily for 14 days.

The patient was recalled after 1 week for suture removal. Healing was satisfactory with no postsurgical compli cations.

He was recalled after 1 and 6 months for further evaluation and maintenance showing appre ciable improve ment in ridge both vertically as well as labiolingually (Figs 8 and 9). Post­operative radiograph (6 months) also showed appreciable improve ment in bone regeneration (Fig. 10). Then finally fixed prosthesis was given to the patient (Fig. 11).

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DISCUSSION

The most commonly seen localized alveolar ridge defects are the combined Class III defects (56% of cases) followed by horizontal Class I defects (40% of the cases). Vertical defects were reported to be found in 4% of the patients.7 Large vertical and horizontal bone defects pose a prosthodontic challenge as it is difficult to restore esthetics and function along with the complete closure of the defect. Such clinical conditions are not successfully treated by conventional fixed or removable prosthesis alone.8 Guided bone regeneration can be successfully used in either a simultaneous approach or a staged approach.9 Four prerequisites need to be fulfilled for predictable success with GTR:7

a. Achievement of primary soft tissue healing: When a soft tissue dehiscence occurs, the exposure of the membrane leads to its contamination with bacteria from the oral cavity and frequently to an infection in the membrane site.

b. Use of an appropriate barrier membrane: The structure of the membrane should not allow the penetration of cells through the membrane, which is an important factor for its success as a physical barrier.

c. Stabilization and dose adaptation of the membrane to the surrounding bone: Close adaptation is necessary to achieve a sealing effect to prevent the ingrowth soft tissue cells derived from the gingival connective tissue, because these cells are able to compete with bone­forming cells in the created space underneath the membrane. In addition, stabilization of the membrane is useful for maintaining close adaptation of the membrane to the bone during wound closure.

d. Creation and maintenance of a secluded space: The use of an appropriate supporting device is useful in surgical sites without an intact buccal bone wall for natural space making.

Autogenous bone grafts stabilize the blood clot, are bio­com patible and absolutely safe from the standpoint of disease transmission, and have good space maintaining capacity.

Additional factors important for achieving complication­free primary soft tissue healing are meticulous and careful handling of the soft tissues, precise wound closure with matt­ress and interrupted sutures, and appropriate post operative treatment and medication.7 Mineralized and demi ne ralized freeze­dried bone allografts have been utilized as a mem­brane­supporting device in ridge augmentation procedures with encouraging clinical results.10 For achie ving predictable results, a sufficiently long healing period is important. Sites of early membrane removal attain less gain in bone height.11

CONCLUSION

The guided bone regeneration procedure is a surgical proce­dure of choice for localized hard tissue ridge augmentation. A predictable result can be achieved if the prescribed surgi­cal protocol is followed. However, the surgical procedure is technically demanding and requires a precise and systematic surgical technique. Furthermore, the method is not comple-tely developed yet. Therefore, the GBR technique should be used with extreme care for predictable results.

REFERENCES

1. Seibert JS. Reconstruction of deformed, partially edentulous ridges, using full thickness onlay grafts. Compend Contin Educ Dent 1983;4(5):437-453.

2. Allen EP, Gainza CS, Farthing GG, Newbold DA. Improved technique for localised ridge augmentation. A report of 21 cases. J Periodontol 1985;56(4):195-199.

3. Nyman S, Karring T, Lindhe J, Planten S. Healing following implantation of periodontitis­affected roots into gingival connective tissue. J Clin Periodontol 1980;7(5):394-401.

4. Melcher AH. On the repair potential of periodontal tissues. J Periodontol 1976;47(5):256-260.

5. Karring T, Nyman S, Lindhe J. Healing following implantation of periodontitis affected roots into bone tissue. J Clin Periodontol 1980;7(2):96-105.

6. Farzad M, Mohammadi M. Guided bone regeneration: A literature review, J Oral Health Oral Epidemiol 2012;1(1):3-18.

7. Abrams H, Kopczyk RA, Kaplan AL. Incidence of anterior ridge deformities in partial edentulous patients. J Prosthet Dent 1987; 57(2):191-194.

8. Philip G, Dayakar MM, Gupta S, Khattri S. Preprosthetic soft tissue ridge augmentation using modified roll technique: a case report. Indian J Dent Sci 2013 Dec;5(5):82-83.

9. Buser D, Dula K, Belser U, Hirt HP, Berthold H. Localized Ridge Augmentation Using Guided Bone Regeneration: Surgical Procedure in the Maxilla. Int J Periodont Rest Dent 1993;13:29-45.

10. Nevins R, Mellonig JT. The advantages of localized ridge augmen tation prior to implant placement: A staged event. Int J Periodont Rest Dent 1994;14:97-111.

11. Simion M, Saldoni M, Rossi R, Zaffe D. A comparative study of the effectiveness of e-PTFE membranes with and without early exposure during the healing period. Int J Periodont Rest Dent 1994;14:167-180.

Fig. 11: Prosthesis placement after 6 months