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 Table of Contents  
ORIGINAL ARTICLE
Year : 2017  |  Volume : 9  |  Issue : 5  |  Page : 180-186  

Assessment of regeneration of bone in the extracted third molar sockets augmented using xenograft (CollaPlugTN Zimmer) in comparison with the normal healing on the contralateral side


1 Department of Oral and Maxillofacial Surgery, Rajah Muthiah Dental College, Chidambaram, Tamil Nadu, India
2 Department of Dental Surgery, Dhanalakshmi Srinivasan Medical College, Perambalur, Tamil Nadu, India
3 Prosthodontics, Rajah Muthiah Dental College, Chidambaram, Tamil Nadu, India
4 SRM Dental College, Kattankulathur, Tamil Nadu, India

Date of Web Publication27-Nov-2017

Correspondence Address:
Murugan Ranganathan
Department of Oral and Maxillofacial Surgery, Rajah Muthiah Dental College, Chidambaram, Tamil Nadu
India
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/jpbs.JPBS_176_17

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   Abstract 


Introduction: Alveolar bone resorption is a significant clinical problem. Bone loss in third molar region following extraction or surgical removal not only leads to periodontal problems in second molar region but also it may lead to some serious problems like increased incidence of angle fractures. In order to reduce the risks following third molar surgery, the socket should be augmented with bone grafts. In recent days guided tissue regeneration is the most accepted and successful technique followed many authors and its efficacy has been proved. Materials and Methods: Based upon our clinical experience, the use of bio absorbable collagen wound dressing such as CollaPlugTN has achieved quick healing and more primary wound coverage. Amongst the graft materials collagen is preferable due to its high biocompatibility and hemostatic ability. This study was done to assess the regeneration of bone in the extracted third molar sockets using xenograft (CollaPlugTN-Zimmer) which was compared with the normal healing on the contra lateral side. The assessment was done to analyze post-operative healing complications and to compare the bone density formed between control site and implant site radiologically. Conclusion: On this basis of this study, the use of collaplugTN appears to be beneficial to the patient in postoperative wound healing and also for better bone formation. The use of this material was advantageous because of its simplicity of application cost effectiveness and availability. There is enhanced wound healing and early bone formation.

Keywords: Socket augmentation, efficacy of collagen, xenograft in socket augmentation


How to cite this article:
Ranganathan M, Balaji M, Krishnaraj R, Narayanan V, Thangavelu A. Assessment of regeneration of bone in the extracted third molar sockets augmented using xenograft (CollaPlugTN Zimmer) in comparison with the normal healing on the contralateral side. J Pharm Bioall Sci 2017;9, Suppl S1:180-6

How to cite this URL:
Ranganathan M, Balaji M, Krishnaraj R, Narayanan V, Thangavelu A. Assessment of regeneration of bone in the extracted third molar sockets augmented using xenograft (CollaPlugTN Zimmer) in comparison with the normal healing on the contralateral side. J Pharm Bioall Sci [serial online] 2017 [cited 2019 Jan 22];9, Suppl S1:180-6. Available from: http://www.jpbsonline.org/text.asp?2017/9/5/180/219295




   Introduction Top


In this emerging field of guided tissue regeneration (GTR), lots of nonresorbable and resorbable collagen membranes have been used along with the bone grafts, either allograft or xenograft,[1] and their efficacy has been proved by many authors. Collagen is one of the most useful biomaterials with excellent biocompatibility and safety due to its biological characteristics, such as biodegradability and weak antigenicity.[2]

In the human body, bone plays an important structural role providing the framework protecting vital organs. It helps in facilitating locomotion and other complex functional movements such as mastication.[3] Structurally, bone is a complex and constantly changing tissue which is capable of self-repair and adaptation to new loads. Two fundamental concepts, modeling and remodeling, are used to describe the dynamic nature of bone. Modeling is the process whereby, in response to some stimulus or physical force, a bone may change in three-dimensional size or shape. An example is the change observed in alveolar bone resorption following the loss of teeth.

The loss of bone following tooth extraction is a significant clinical problem. Bone loss in the third molar region, following extraction may not only lead to periodontal problems[4],[5] in the second molar region but also it may lead to some serious problems such as increased incidence of angle fractures.[6] To reduce the risks following third molar surgery, the socket should be augmented with bone grafts. The literature has shown that early bone loss can be significantly reduced by advanced socket management. The process of socket grafting is not technically difficult but does require an understanding of wound healing and an appreciation of the biological properties of the products available for socket grafting. In recent days, GTR is the most accepted and successful technique followed many authors and its efficacy has been proved.[7]

In this emerging field of GTR, lots of nonresorbable and resorbable collagen membranes have been used along with the bone grafts, either allograft or xenograft, and their efficacy has been proved by many authors. Among the graft materials, collagen is preferable due to its high biocompatibility and hemostatic ability that can enhance platelet aggregation and thus facilitate clot formation and wound stabilization. Based on our clinical experience, the use of bioabsorbable collagen wound dressing such as CollaPlugTN has achieved quick healing and more primary wound coverage.

Aims and objectives

This study was done to assess the regeneration of bone in the extracted third molar sockets using xenograft (CollaPlugTN Zimmer) which was compared with the normal healing on the contralateral side. The assessment was done to analyze postoperative healing complications and to compare the bone density formed between control site and implant site radiologically. The main objectives of the study are: (1) to assess the compatibility of the material with the host tissue, (2) to achieve primary healing, (3) to assess the efficacy of the material in regeneration of bone, and (4) to decrease the intrabony defect distal to second molar. A clinical and radiological comparative study was undertaken to evaluate the osteogenic potential of collagen in the third molar extraction sockets.


   Materials and Methods Top


Materials

In this study, 10 patients of both sexes with symmetrical, bilateral impacted mandibular third molars in the age group of 18–2 years were selected from the Outpatient Department of Oral and Maxillofacial Surgery, Rajah Muthiah Dental College and Hospital, during the period of 2008–2009.

Description of the xenograft

CollaPlugTN (xenograft) (manufacturer - Zimmer)[Figure 1] is an absorbable collagen bone wound dressing. It is a soft, white, pliable, nonfriable sponge. The material retains its structural integrity even when wet. It is very porous. Greater than 90% of the material consists of open pores, which can fill with fluid. It is highly absorbent, holding many times their own weight of saline solution. The basic material from which the absorbable collagen wound dressings are fabricated is collagen obtained from bovine deep flexor (Achilles) tendon. The tendon is one of the purest sources of collagen that can be readily obtained and processed in commercial quantities. Each dressing is packaged individually. An inherent property of native collagen is the ability to promote hemostasis. In contact with blood, collagen is known to cause aggregation of platelets, which bind in large numbers to the collagen fibrils. The aggregated platelets degranulate, releasing coagulation factors that enable, together with plasma factors, the formation of fibrin. The sponge structure of the absorbable collagen wound dressings provides a three-dimensional matrix for additional strengthening of the blood clot which will prevent the epithelial entrapment to the extracted socket. This CollaPlug guides the tissue for regeneration and thus it increases the bone formation. The absorbable collagen wound dressings have been tested for potential allergenic sensitivity and cytotoxicity. The sponges contain no toxic leachables, do not produce tissue irritation, and show no contact sensitization. Passive hemagglutination, which is a sensitive test for potential antigenicity, was used with the absorbable collagen wound dressings as the antigen. There was no agglutination observed.
Figure 1: Absorbable collagen wound dressing – collaplug (trade name)

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Methods

Ten patients aged from 18 to 32 years with impacted mandibular third molars in a symmetrical position according to the classification of Winter and scheduled for extraction were selected for this study. The inclusion criteria were patients with no systemic disorder whose adjacent second molars were intact and well positioned. Pregnant women and smokers were excluded from the study. Patients were extensively informed about the procedures, including the uncertainties of using a new bone regenerative material. They were asked for their full cooperation during treatment and research on a voluntary basis. All received and signed a written informed consent.

Each patient had one of their sockets in the control group and the other in experimental group, and they were selected randomly. In the control group, standard third molar surgical procedures were performed using aseptic protocol. On the other side, the bony defect following extraction of third molar was filled with collagen. This served as the implant side.

Surgical procedure

Routine principles and methodology were followed in surgical removal of third molars in all patients. The socket was irrigated with normal saline and was examined for any remnants of follicular tissue and when present was curetted out. Then, the socket was isolated, and CollaPlugTN (Zimmer) was placed inside the socket gently without compressing it. The material was placed till the level of alveolar crest. The mucoperiosteal flap was approximated and the wound was primarily closed with 3.0 silk sutures. Then, the third molar of the contralateral side was surgically removed. The wound was closed primarily. This served as the control side. Routine postoperative instructions and antibiotics and analgesics were given.

Patients were recalled on the next day postoperatively and then the 2nd and 4th week of postoperative period. The presence of edema and any signs of wound dehiscence or extrusion of the material was observed. The sutures were removed after 7 days. Intraoral periapical radiographs were taken immediate postoperatively and then at the end of 1st week, 4th week, and 12th week of surgery. The radiographs were taken under standardized conditions to obtain an optimal film density and contrast. Long-cone paralleling technique was followed for all intraoral radiographs. Kodak periapical films were used and processed in a standardized way.

Postoperative assessment

The patients were assessed postoperatively for a period of 4 weeks starting from the day of surgery. The assessment was done clinically and radiologically.

Clinical assessment

The patients were recalled on following days: (i) 1st day postoperatively, (ii) 1st week postoperatively, (iii) 2nd week postoperatively, and (iv) 4th week postoperatively. Clinically, the following criteria were assessed: (a) edema, (b) postoperative pain, (c) infection, (d) wound gaping, and (e) extrusion of the material.

Edema

The patients were assessed for the presence or absence of postoperative edema in both control and implant side [Table 1]. If present, it was measured by a measuring tape. Depending on the size of the swelling, it is graded as follows:
Table 1: Edema

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  • Absent
  • Mild <1 cm diameter
  • Moderate <2 cm diameter
  • Severe >2 cm diameter.


On the 1st day postoperatively, six patients had moderate swelling, three had mild swelling, and swelling was not obvious in one of the cases in the implant side. On the control side, one had severe swelling, six had moderate swelling, and three had mild swelling. On the 1st week postoperatively, swelling was totally reduced in eight patients, mild in one patient, and moderate in one patient in implant side. On the control side, swelling was not obvious in six patients and mild in four patients. On the 2nd week postoperatively, there is no obvious swelling seen in none of the patients on both the groups. On clinical follow-up of the 4th week, none of the patients in both the groups had swelling.

Pain

Pain criteria were assessed by the visual analog scale. Depending on the intensity of pain, it was scored as follows: 0 - no pain, 1 - has mild pain, 2 - has moderate pain, and 3 - has severe pain. On the 1st day postoperative period, six patients had moderate pain and four patients had mild pain in implant side. In control side, only three patients had moderate pain and seven patients had mild pain. On the 1st week postoperative period, four patients had moderate pain and six patients had severe pain in implant side. In control side, there was a slight increase in pain for seven patients and all the patients had moderate pain. On the 2nd week of postoperative period, two patients had moderate pain and eight patients had mild pain in implant side. In control side, five patients had moderate pain and five had mild pain. On the 4th week of postoperative period, all the cases had no pain in implant side. In control side, seven had no pain and three had mild pain [Table 2].
Table 2: Pain

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Wound gaping

On the 1st week postoperatively, gaping was not seen in nine cases and gaping was seen in only one patient in implant side. In control side, eight cases showed gaping, and in two cases, there was no gaping seen. On the 2nd week postoperatively, none of the cases in implant side showed gaping, but in control side, six patients had gaping and four showed no gap. On the 4th week postoperatively, there is no gaping seen in all the cases in implant side, but in control side, gaping was seen in two cases [Table 3].
Table 3: Gaping of wound

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Infection was not seen in any of the cases in both control and implant side for a period of 4-week follow-up.

Extrusion of material

None of the cases of implant side reported with extrusion of the material [Table 4].
Table 4: Infection

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Radiographic assessment

Intraoral periapical radiographs of the implant and control sides were taken at regular intervals – immediate postoperative, 1st week postoperative, 2nd week postoperative, and 4th week postoperatively. As the implant material is not a radiopaque material, we cannot differentiate the material from normal bone in the immediate postoperative period. However, over a matter of few weeks, bone formation occurs and is seen radiographically.

  1. Immediate postoperative radiographs of the implant side showed no significant changes, when compared to control side as our material is not radiopaque
  2. On the 2nd week of postoperative follow-up period, there was a marked radiopacity seen in implant side compared to control side. On the 4th week of postoperative follow-up period, the extracted socket shape was not seen in implant side as the socket has been filled with newly formed bone control side showed less radiodensity when compared to implant side.



   Discussion Top


Structurally, bone is a complex and constantly changing tissue which is capable of self-repair and adaptation to new loads. Two fundamental concepts, modeling and remodeling, are used to describe the dynamic nature of bone. Modeling is the process whereby, in response to some stimulus or physical force, a bone may change in three-dimensional size or shape. An example is the change observed in alveolar bone following the loss of teeth. In this case, osteoclastic resorption becomes uncoupled form and outpaces osteoblastic deposition, resulting in a net loss in bone mass. Clinically, this phenomenon is manifest as alveolar ridge resorption.[3]

The backbone of most practices remains dentoalveolar surgery and that too third molar surgery. The efficient delivery of care in this surgical area not only involves accurate diagnosis, effective anesthesia, and skillful surgical technique but also the sequence of normal biologic events that result in a healed extraction site without untoward sequelae.[8] The healing of extraction wounds in experimental animals has been studied in the past by many investigators. Although different investigators have done experimental animal studies in healing of wound following extraction, there are only limited studies observing changes in extraction site of humans. Extraction sites heal in a highly predictable fashion, with little intervention required for clinically acceptable wound healing to occur.[8] The initial step involves the formation of a blood clot in the socket. At the apical aspect of the socket, the clot is rapidly replaced by a highly vascular granulation tissue, accompanied by ingrowth of blood vessels from the periodontal plexus. By about 14 days, this granulation tissue is replaced by an organized connective tissue matrix which is eventually mineralized to form bone. Socket healing progresses in an apical to coronal direction so that by 21 days, approximately two-third of the socket is filled with the connective tissue required to form bone (osteoid). Bone formation begins in the apex, progressing coronally to partially fill the socket with immature bone by 6 weeks.[8] The exact sequence of normal healing does not always occur. In some instances, at the coronal aspect, however, within hours of extraction, migrating epithelium invades the clot, resulting in incomplete bone regeneration in the upper one-third–one-fourth of the socket. As a result, the extraction site heals in a concave fashion. Impaction of debris and bacteria into the healing socket further prevents the formation of bone. Incomplete repair at the coronal aspect of the socket coupled with surgical microtrauma to the facial or lingual cortex results in extensive modeling of the residual alveolar crest. As much as 40%–50% of alveolar width and 20%–30% of height are irreversibly lost in the 1st year following extraction. Progressive atrophy following tooth loss ultimately results in the thin, knife-edge ridge or total loss of the alveolus down to basal bone. The rate of ridge resorption is related to a host of local and systemic factors and may be highly variable.[3]

Surgical removal of the impacted third molar tooth is the most commonly performed operation by oral and maxillofacial surgeons, but like many other clinical problems, the impacted third molar presents more a question of management than of treatment. A retrospective study on mandibular fractures following third molar extraction was done by Lizuka, and they concluded that bone loss following third molar surgery may predispose to fracture of mandible.[6]

A number of augmentation procedures are performed today, including preservation and repair of buccal wall defects of the alveolar ridge after tooth extraction. Bone grafting to augment skeletal healing has become one of the most common surgical techniques in recent years. However, the morbidity and limited availability associated with autografts and the potential for disease transmission, immunogenic response, and variable quality associated with allografts have led to a wide variety of alternative materials. Various bone grafting materials are currently being used in alveolar bone grafting procedures. However, all have limitations in their ability to restore the alveolar ridge adequately. The limitations include inadequate blood supply, inconsistent performance, inability to restore alveolar ridge height, prolonged healing, and potential adventitious agent (viral) transmission (allogenic bone).[9] Characteristics of an ideal bone graft substitute consist of a product that is nontoxic and noncarcinogenic, consistently induces bone formation, is readily available, has an unlimited supply, and is easy to use.[9] Given these limitations and characteristics, the ideal agent to restore the alveolar ridge has not yet been identified. Autogenous bone is considered ideal because of its osteoconductive and osteoinductive properties and because it contains a source of osteoprogenitor cells. It is still considered the gold standard by which other grafting materials are compared. However, the search for a bone graft substitute continues because of the disadvantages such as donor-site morbidity, need for a second surgical site, possible hospitalization, need for a general anesthetic, and a limited amount of graft available dependent on the donor site chosen.

Among these bone grafting techniques, GTR or bone regeneration is more emerging and most accepted technique in socket augmentation.[10],[11] GTR has nowadays become an essential therapeutic procedure not only for the treatment of periodontal bone defects but also for bone and peri-implant defects and for bone augmentation procedures before implant placement. In the latter situation, it is sometimes termed guided bone regeneration (GBR) or guided bone augmentation. The technique is based on the concept of preventing the apical downgrowth of the gingival epithelium inside the osseous defect, creating a secluded space that can be colonized by regenerative potential cells, such as PDL fibroblasts, cementoblasts, and bone cells. A material that is used as a barrier for GBR/GTR has to satisfy some physicochemical characteristics to provide for biocompatibility, tissue integration, cell occlusivity, space making ability, and also ease of use in the clinic. The first generation of membranes was nonresorbable, mostly made from expanded polytetrafluorethylene.[12] However, one limitation of nonresorbable membranes is the need for a second surgery to remove the barrier. This may injure the obtained regenerated tissue since it is evident that flap elevation results in a certain amount of crestal resorption of the alveolar bone. Furthermore, early spontaneous exposure to the oral environment and subsequent bacterial colonization has been reported to be common problems of nonresorbable membranes, which could necessitate their premature retrieval. To overcome these problems, a variety of synthetic resorbable materials, such as polylactide-based sponges[13] and collagen in different forms, were used. Several studies confirmed that collagen is better in bone formation than polylactide sponge and polyglycolic acids.[13] In this study, we have used type 1 collagen of bovine origin.

Collagen is the most abundant protein in human beings and animals, constituting 20%–30% of the total body protein.[14] It is found in high concentrations in tendon, skin, and bone. For the last decade, collagen has been used extensively for its properties as a biomaterial for such purposes as membranes for the artificial kidney, replacement of the vitreous body of the eye, soft-tissue augmentation, and bone replacement in the mandible. In addition to its very poor antigenicity and because it is an initiator of hemostasis, collagen has been described by many authors as the material of choice for prevention and control of bleeding. This suggests that, because of these properties, collagen may be useful as a dressing after tooth extraction and perhaps in the prevention of localized osteitis.

Collagen is proven to have osteogenic potential in dogs.[15] Güngörmüs and Kaya did a histological study to conclude that type I collagen provides a more rapid regeneration in human bone defects.[16] Due to ethical reasons as our patients are not in the need of implants in the third molar region, we were not able to perform histological study.

The gaping of wound is a most frequent feature found postoperatively after third molar removal. In our study, only one patient from implant side showed gaping, but eight patients on control side showed gaping. The favorable result obtained on the implant side is attributed to the underlying collagen which gives support to the approximated flap and also probably due to the influence of platelets in the healing process. The gaping of wound in the control side may be due to the absence of clot and seepage of oral fluids through the approximated flap.

The study done by Adeyemo et al. suggested that 12% of people are having alveolar osteitis following extraction of teeth.[17] In our study, it was observed that there was no infection seen in both implants and control sides. On the implant side, it may be attributed to the absence of dead space, good primary healing of the soft tissues, and administration of systemic antibiotics. On the control side, the absence of infection in all probabilities may be due to constant irrigation of the socket to remove the accumulated food particles and also administration of systemic antibiotics.


   Conclusion Top


In our study, none of the cases showed extrusion of the material in implant site. This shows the biocompatibility of the material. The clinical ease to use this material is also one of the noticeable factors. The collagen being a radiolucent material, radiographic evaluation was not feasible immediately after impaction in our study. Bone formation was seen slightly higher in implant site than the control site on the 4th week of postoperative period. As suggested by Güngörmüs and Kaya, collagen kept in implant site quickened the healing process and the bone defects had filled in very short period. There was a progressive increase in the diffuse radiopacity in the implant side when compared to control side which is indicative of fresh bone formation. This shows that there was early and faster bone formation on the implant side when compared to the control side.

On this basis of this study, the use of CollaPlugTN appears to be beneficial to the patient in postoperative wound healing and also for better bone formation. CollaPlug was placed as filler and scaffold to facilitate bone formation and promote wound healing in the socket following surgical removal of impacted third molar. Clinical evaluation showed good healing, primary closure on the implant side with no postoperative care while the control side required constant postoperative irrigation of the socket.

Radiographic analysis showed that there was faster formation of bone in the implant side compared to the control side and absence of intrabony defect distal to second molar on the implant side. The use of this material was advantageous because of its simplicity of application cost-effectiveness and availability. There is enhanced wound healing and early bone formation.

As our study consists of only ten patients, the fate of collagen material and its role in bone formation needs to be investigated further with long-term follow-up and with a larger sample. The clinical application of collagen should not only be restricted with third molar augmentation but also it should be used with other socket augmentations.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.



 
   References Top

1.
Indovina A Jr., Block MS. Comparison of 3 bone substitutes in canine extraction sites. J Oral Maxillofac Surg 2002;60:53-8.  Back to cited text no. 1
    
2.
Lee CH, Singla A, Lee Y. Biomedical applications of collagen. Int J Pharm 2001;221:1-22.  Back to cited text no. 2
    
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Bartee BK. Implant site development and extraction site grafting. Osteogenics Clinical Education, 2009. Osteogenics Biomedical inc.  Back to cited text no. 3
    
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Kugelberg CF. Periodontal healing after impacted lower third molar surgery. Int J Oral Surg 1985;14:29-40.  Back to cited text no. 4
    
5.
Richardson DT, Dodson TB. Risk of periodontal defects after third molar surgery: An exercise in evidence-based clinical decision-making. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2005;100:133-7.  Back to cited text no. 5
    
6.
Lizuka T. Mandibular fractures following third molar extraction – A retrospective clinical and radiological study. Int J Oral Maxillofac Surg 1997;26:338-43.  Back to cited text no. 6
    
7.
Colangelo P, Piattelli A, Barrucci S, Trisi P, Formisano G, Caiazza S. Bone regeneration guided by resorbable collagen membranes in rabbits: A pilot study. Implant Dent 1993;2:101-5.  Back to cited text no. 7
    
8.
Boyne PJ. Osseous repair of the postextraction alveolus in man. Oral Surg Oral Med Oral Pathol 1966;21:805-13.  Back to cited text no. 8
    
9.
Scabbia A, Trombelli L. A comparative study on the use of a HA/collagen/chondroitin sulphate biomaterial (Biostite) and a bovine-derived HA xenograft (Bio-Oss) in the treatment of deep intra-osseous defects. J Clin Periodontol 2004;31:348-55.  Back to cited text no. 9
    
10.
Dodson TB. Reconstruction of alveolar bone defects after extraction of mandibular third molars: A pilot study. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 1996;82:241-7.  Back to cited text no. 10
    
11.
Barber HD, Lignelli J, Smith BM, Bartee BK. Using a dense PTFE membrane without primary closure to achieve bone and tissue regeneration. J Oral Maxillofac Surg 2007;65:748-52.  Back to cited text no. 11
    
12.
Mehlisch DR, Leider AS, Roberts WE. Histologic evaluation of the bone/graft interface after mandibular augmentation with hydroxylapatite/purified fibrillar collagen composite implants. Oral Surg Oral Med Oral Pathol 1990;70:685-92.  Back to cited text no. 12
    
13.
Taira M, Araki Y, Nakao H, Takahashi J, Hyon SH, Tsutsumi S. Cellular reactions to polylactide-based sponge and collagen gel in subcutaneous tissue. J Oral Rehabil 2003;30:106-9.  Back to cited text no. 13
    
14.
Patino MG, Neiders ME, Andreana S, Noble B, Cohen RE. Collagen: An overview. Implant Dent 2002;11:280-5.  Back to cited text no. 14
    
15.
Araújo MG, Lindhe J. Ridge preservation with the use of Bio-Oss collagen: A 6-month study in the dog. Clin Oral Implants Res 2009;20:433-40.  Back to cited text no. 15
    
16.
Güngörmüs M, Kaya O. Evaluation of the effect of heterologous type I collagen on healing of bone defects. J Oral Maxillofac Surg 2002;60:541-5.  Back to cited text no. 16
    
17.
Adeyemo WL, Ladeinde AL, Ogunlewe MO. Clinical evaluation of post-extraction site wound healing. J Contemp Dent Pract 2006;7:40-9.  Back to cited text no. 17
    


    Figures

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    Tables

  [Table 1], [Table 2], [Table 3], [Table 4]



 

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