Dr. Amit Patel, UK. Private Practice. Birmingham, United Kingdom. FIG. 1: ONE-, TWO- AND THREE-WALL PERIODONTAL BONE DEF
Periodontal regeneration
Where we started and where we are going Dr. Amit Patel, UK Private Practice Birmingham, United Kingdom
Regenerative surgical procedures have long been considered a suitable method for restoring lost periodontal structure and functional attachment using the regeneration of cementum, periodontal ligament, and alveolar bone. But how did the regenerative concept develop? And what can we expect in the future?
proper function and aesthetics in patients affected by periodontitis. Accordingly, it has been argued that periodontally compromised teeth should be treated for as long as possible and should only be extracted when periodontal and endodontic treatments are no longer possible.1,2 The extraction of teeth affected by periodontitis will not resolve the underlying host response problems contributing to the disease. Moreover, periodontally compromised but treated teeth are known to have survival rates equal to the survival rates of implants in well-maintained patients.3
ourselves on a daily basis is: should we extract the tooth and replace it with a dental implant? This is a difficult question to answer, as both clinicians and patients are becoming aware that implants are not a permanent solution. Nowadays peri-implantitis reports are increasing, and many factors influence its risk, including bacterial and possible occlusal factors. But when one looks at the evidence, a tooth can last a lifetime if maintained correctly by both the patient and the clinician.
Every dentist aims to improve and restore
Therefore, the question we should ask
In the past, periodontal regeneration was considered a treatment modality that allowed the patient to keep a tooth that was periodontally involved. The concept arose from the understanding of the healing of a periodontal pocket based on the studies of Murray et al., Hurley et al., and Melcher et al., where they noted that the epithelium had a protective role for the root surface.4-6 The authors also showed that the rapid proliferation of the epithelium and gingival connective tissue formed long junctional epithelium. Later, a study by Nyman et al. demonstrated that the isolation of epithelium and gingival connective tissue from a periodontal defect using a barrier allowed the periodontal defect to heal with bone, periodontal ligament and cementum.7 This study
FIG. 1: ONE-, TWO- AND THREE-WALL PERIODONTAL BONE DEFECTS.12
Illustration: Quaint
ONE WALL DEFECT
TWO WALL DEFECT
THREE WALL DEFECT
The concept of periodontal regeneration in the beginning
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FIG. 2: MINIMALLY INVASIVE APPROACH FOR PERIODONTAL REGENERATION IN A VERTICAL BONY DEFECT
A 41-year old non-smoking female developed generalized chronic periodontitis. She underwent a course of successful non-surgical therapy. Only one localized periodontal pocket did not resolve: the
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upper left lateral retained a vertically bony defect. Periodontal regeneration was discussed as an option to improve the long-term prognosis. Therefore, a minimally invasive surgical technique
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E
C
D
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H
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Photos: Amit Patel
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was utilized preserving the papillae. The bony defect was curetted, and the root surface was prepared for enamel matrix proteins and the placement of Geistlich Bio-Oss®.
| A Clinical situation before treatment: buccal view of an 8 mm pocket at the maxillary left site #11, mesial. | B Periapical long cone radiograph showing the vertical bony defect. | C No pocketing at site upper left one. | D Minimally invasive surgical technique: buccal incision. | E Minimally invasive surgical technique: flap is raised palatally. | F A two wall vertical defect is observed. | G Enamel matrix protein is placed into the defect. | H Geistlich Bio-Oss® is placed into the defect. | I Suturing with 5/0 polypropylene non-resorbable sutures (Laurell Gottlow Suture). | J Clinical situation 1-week post-op and suture removal. | K Buccal view at 1-year follow-up. | L Occlusal view at 1-year follow-up. | M-N No pocketing resolution of the vertical defect is observed at 1-year follow-up. | O Periapical long cone radiograph showing resolution of the vertical bony defect.
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GEISTLICH NEWS 1-2018
“The question we should ask ourselves on a daily basis is: should we extract the tooth and replace it with a dental implant? This is a difficult question to answer.”
References 1
Lang NP, et al.: Ann Periodontol 1997; 2(1): 343-356.
2 Schwarz F, et al.: Peri-implant Infection: Etiology, Diagnosis and Treatment. Quintessence Publishing. 2007. 3 Roccuzzo M, et al.: Journal of Clinical Periodontology 2011; 38(8): 738–45. 4 Murray G, et al.: American Journal of Surgery 1957; 93: 385–387. 5 Hurley LA, et al.: The Journal of Bone and Joint Surgery 1959; American volume 41-A: 1243–1254. 6 Melcher AH, Dreyer CJ: Journal of Bone and Joint Surgery 1962; 44B: 424. 7 Nyman S, et al.: J Clin Periodontol 1980; 7(5): 394-401.
heralded the technique of Guided Tissue Regeneration (GTR) for periodontal regeneration by first utilizing a non-resorbable expanded polytetrafluoroethylene (ePTFE) and later a resorbable collagen membrane placed over a periodontal defect,8 sometimes filled with a bone graft.9,10
lagen membrane. On the other hand, if the bony defect is localized, then curetting the defect and assessing if the clot can be stabilized by the flap alone or by placing a bovine bone graft, sometimes mixed with enamel matrix proteins, enhances the outcome though less invasive periodontal regeneration. (Fig. 2)
Current concept
Future perspectives
The bony defects that allow greater predictably of periodontal regeneration are three- and two-wall defects.(Fig. 1) Three-wall defects provide the highest amount of regeneration due to the number of walls surrounding the bony defects able to stabilize the blood clot for proper healing and maturation and able to contribute the most bone cells for bony healing at the site. Over time surgical technique and technology have advanced to the point where we are now raising the tissues only slightly using the minimally invasive surgical technique (MIST) as suggested by Cortellini et al.11 The concept focuses on not elevating the gingiva too much to evaluate and treat periodontal defects. If the defect extends to another tooth or is circumferential, then the gingival tissues can be elevated further to expose the defect, and more traditional periodontal regeneration techniques can be performed by placing a bovine bone graft and a col-
Raising large periodontal flaps is turning into a treatment of the past, while performing minimal flaps is growing more common in everyday practice. Due to greater predictably of the techniques and better understanding of the biology of periodontal disease and healing, we can now reduce the morbidity involved with more extensive surgical procedures, and we can avoid placing dental implants in younger patients – improving the prognosis for teeth before considering implants. And it is clear that we need to acknowledge periodontal regeneration as a predictable modality.
8 Scantlebury T, Ambruster J: J Evid Based Dent Pract 2012; 12(3 Suppl): 101-17. 9 Mellonig JT, Bowers GM: J Am Dent Assoc 1990;121(4):497-502. 10 McClain PK, Schallhorn RG: Int J periodontics Restorative Dent 1993;13(1):9-27. 11 Cortellini P, Tonetti MS: J Clin Periodontol 2007; 34(1): 87-93. 12 Goldman HM, Cohen DW: Journal of Periodontology 1958; 29(4): 272-291.
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