With the aim of achieving an optimal esthetic result in implant dentistry, special care is being taken to focus on the details that would lead to this objective. These details may include imitating the natural teeth, by harmonizing the structures around the placed implant. The prosthetic and/or surgical parts of the procedure should be performed to reach an optimal outcome. In order to minimize the resorption of hard and soft tissue, that exists around the newly extracted tooth – to create a natural emergence profile of implant born prosthesis – socket preservation procedures were introduced, however, in case of ridge deficiencies, hard and soft tissue augmentation procedure are indicated. Several approaches have been described in the literature to overcome the complications of alveolar ridge resorption and to preserve the ridge like hard and soft tissue augmentation with GBR, bone substitutes with or without immediate implant placement. An ideal method should always be cost effective and minimally invasive. In this paper, we will present case report using a new approach in socket ridge preservation, which is the socket shield technique (partial root retention).
Immediate implant; Socket-shield technique; alveolar ridge resorption
Healing of extraction sockets are characterized by bone formation within the socket and loss of alveolar ridge width and height externally (1). The alteration of ridge contour may compromise the restoration-oriented three-dimentional positioning of the implant which requires optimal support and stability of surrounding hard and soft tissues (2). In esthetic region, the height and thickness of facial and interproximal bone walls are the important factors for successful pink esthetic outcomes, which are made up by color, shape and character of the marginal peri-implant mucosa and presence of interdental papilla (3). Various techniques have been described in literature to overcome these negative consequences of tooth extraction such as hard and soft tissue augmentation with GBR, bone grafts following extraction with or without immediate implant placement (4). However, immediate implant placement still does not prevent buccal bone resorption as it is a biological phenomenon (5).
Araujo and Lindhe suggested that following tooth extraction, the blood vessels in periodontium to the thin bone walls are severed, thereby causing facial bone plate resorption(6). Thus it can be assumed that retaining a root may alter the occurrence of facial bone resorption.
The “socket shield technique” has demonstrated the potential to prevent buccal tissue from resorption in animal and clinical studies. It is assumed that retaining the root fragment attached to the buccal bone plate in this technique can avoid tissue alteration after tooth extraction. This article presents a 27 year-old healthy female with a fractured upper right lateral incisor which would be replaced by an implant supported single crown. Leaving a partial root fragment at buccal side in combination with immediate implant placement lingual to the retained fragment was performed. One year after implant placement, clinical examination showed healthy peri-implant soft tissue and ridge was preserved. A crown was fabricated and cemented on a titanium abutment. The prosthesis successfully restored function of the patient. Applying socket shield technique and immediate implant placement may be a feasible treatment option in case with high esthetic concern.
THE PRINCIPLE OF SOCKET-SHIELD (SS) TECHNIQUE
a) Preparation of the root of a tooth indicated for extraction in such manner that the buccal/facial root section remains in-situ with its physiological relation to the buccal plate intact.
b) The tooth root section’s periodontal attachment apparatus (periodontal (PDL), attachment fibers, vascularization, root cementum, bundle bone, alveolar bone) remain vital and undamaged to prevent the expected post-extraction socket remodeling and to support the buccal/facial tissues.
c) The prepared tooth root section acts as a socket-shield and prevents the recession of tissues buccofacial to an immediately placed implant.
STEP BY STEP PROCEDURE
a) Local anaesthesia should be administered. The crown of the tooth to be extracted is decoronated with a coarse-grained diamond bur.
b) The root of the tooth is sectioned mesiodistally with a long tapered fissure diamond bur coupled to a hydrated high-speed hand piece into facial and palatal halves followed by conservative extraction of the palatal root fragment using periotome, luxators and forceps preserving the facial root section unmanipulated and attached to the tooth socket.
c) Periotomes can be inserted between the palatal root section and the alveolar socket wall to severe the PDL and the section of root can then be carefully delivered with so as not to disturb the facial root section.
d) The tooth socket’s palatal wall and apex are then curetted to remove any tissue of infective remnants.
e) With the preparation steps complete, the tooth root hereafter was known as the socket-shield (SS).
f) If planned for an immediate implant placement, an ostectomy is then sequentially prepared and a selected implant was inserted palatal to the socket shield.
g) The gap between the shield and implant surface was left to enable blood clot formation.
h) Sockets can be closed with sutures.
Sequence of detailed procedure followed for immediate implant prosthesis using Socket Shield Technique
a) Help ensure physiological preservation of labial and buccal bone structures if implant is placed in contact to the natural tooth fragment (shield) and prevent lamellar bone resorption.
b) Tissue prerservation-preserves healthy periimplant tissues.
c) Buccal shield serves as a guiding structure when placing implants in optimum position.
d) Complete osseointegration can be achieved.
e) Formation of fibrous tissue around implant can be avoided.
f) Cost effective.
g) Minimal invasiveness.
h) Minimal material requirement (no bone substitute, GTR etc).
i) Offers a feasible option for vertically fractured teeth.
j) Helps maintain aesthetics.
DISADVANTAGES AND LIMITATIONS :
a) Resorption associated with usual biological long term complication that may occur especially in the presence of pre existing or developing periodontal or endodontic infections or inflammations of the retained root fragments.
b) Technique sensitive. Displacement of buccal root fragment or even buccal lamellar bone.
c) Long term behaviour of the buccal shield has not yet been completely clarified.
This case illustrates an experimental technique for preserving a buccal root segment in conjunction with immediate implant placement and provisionalisation. The socket shield technique may be valuable technique to minimize buccal contour changes after tooth extraction, leading to increased volume stability of the mucosa adjacent to the inserted implant. However, it is important to note that this technique should not be used in daily practice until long term multicentre studies are available.
1. Schropp L, Wenzel A, Kostopoulos L, Karring T. Bone healing and soft tissue contour changes following single-tooth extraction : a clinical and radiographic 12-month prospective study. Int J Period Restro Dent 2003; 23: 313-23.
2. Buser D, Martin W, Belser UC. Optimizing esthetics for implant restorations in the anterior maxilla: anatomic and surgical considerations. Int J Oral Maxillofac Implants 2004; 19 Suppl : 43-61.
3. Belser UC, Grutter L, VailatiF, Bornstein MM, Weber HP, Buser D. Outcome evaluation of early placed maxillary anterior single-tooth implants using objective esthetic criteria: a cross-sectional, restrospective study in 45 patients with a 2- to 4-year follow-up using pink and white esthetic scores. J Periodontol 2009; 80:140-51.
4. Wadhwani P, Goyal S, Tiwari S, Syed S, Paul T, Komal A. Socket Shield Technique : A New Concept of ridge preservation. Asian Journal of Oral Health & Allied Sciences. 2015;5(2):55.
5. Chen CL, Pan YH. Socket Shield Technique for Ridge Preservation: A Case Re-port. J Prosthodont Implantol. 2013;2(2) :16-21.
6. Araujo MG, Lindhe J. Dimensional ridge alterations following tooth extraction. An experimental study in the dog. J Clin Periodontol 2005; 32:212-8.
7. Gluckman H, Du Toit J, Salama M (2015) The socket shield technique to support the buccofacial tissues at immediate implant placement. International dentistry-african edition 5 (3)