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ORIGINAL ARTICLE
Year : 2014  |  Volume : 3  |  Issue : 5  |  Page : 28-36

Comparison of β-tricalcium phosphate and autogenous bone graft with bioabsorbable membrane and autogenous bone graft in the treatment of intrabony periodontal defects: A clinico-radiographic study


1 Department of Periodontology, GITAM Dental College and Hospital, Visakhapatnam, Andhra Pradesh, India
2 Department of Periodontology, Best Dental Science College and Hospital, Madurai, Tamil Nadu, India

Date of Web Publication10-Mar-2014

Correspondence Address:
Narendra Reddy Motakatla
Room No. 3, Ultra's Best Dental Science College, Ultra Nagar, Madurai - 625 104, Tamil Nadu
India
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/2277-8632.128487

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  Abstract 

Aim: The aim of this study was to compare clinically and radiographically, the regenerative potential of β- tricalcium phosphate and autogenous bone graft with a bioabsorbable membrane and autogenous bone graft in the treatment of intrabony periodontal defects.
Materials and Methods: A total of 24 sites from 12 patients showing bilateral or contralateral intrabony defects were selected and randomly divided into experimental site A (CERASORB® + autogenous bone graft) and experimental site B (BIOMEND + autogenous bone graft) by using the split mouth design. Clinical parameters like plaque index, was recorded at 1, 3, 6, 12 months and probing pocket depth (PPD), clinical attachment level (CAL) and gingival recession were recorded at baseline, 6 and 12 months along with radiographs to evaluate defect fill, change in alveolar crest height and percentage of defect fill.
Statistical Analysis: For intragroup variations-Student paired t-test, for comparison between the two groups-unpaired t-test and for the comparison of plaque index at different time intervals-Wilcoxon matched pairs test were used.
Results: Both groups showed clinically and statistically significant reduction in PPD and gain in CAL with no statistical significance. Radiographically, in site A there was significant defect fill of 69.58% and 79.24% at 6 and 12 months. In site B, a defect fill of 71.29% and 82.77% was seen at 6 and 12 months.
Conclusion: Both groups showed the potential of enhancing the periodontal regeneration; however, on comparison between the two groups, the results obtained of the BIOMEND + autogenous bone graft group were slightly better, although statistically not significant.

Keywords: Autogenous bone graft, biomend, cerasorb, composite graft, guided tissue regeneration, intrabony defect, periodontal regeneration


How to cite this article:
Rao KP, Bari K, Motakatla NR, Penmatsa T. Comparison of β-tricalcium phosphate and autogenous bone graft with bioabsorbable membrane and autogenous bone graft in the treatment of intrabony periodontal defects: A clinico-radiographic study. J NTR Univ Health Sci 2014;3, Suppl S1:28-36

How to cite this URL:
Rao KP, Bari K, Motakatla NR, Penmatsa T. Comparison of β-tricalcium phosphate and autogenous bone graft with bioabsorbable membrane and autogenous bone graft in the treatment of intrabony periodontal defects: A clinico-radiographic study. J NTR Univ Health Sci [serial online] 2014 [cited 2019 Nov 21];3, Suppl S1:28-36. Available from: http://www.jdrntruhs.org/text.asp?2014/3/5/28/128487


  Introduction Top


The ultimate goal of periodontal treatment is the regeneration of tissues that have been lost due to periodontal disease. Substantial histological and clinical evidence over the last two decades indicates that the regeneration of lost periodontal tissues due to periodontitis can be achieved in humans. Two clinical approaches have been routinely used for the regeneration of lost periodontal tissues: Bone grafting and guided tissue regeneration (GTR) with barrier membranes.

The use of barrier membranes has allowed the selective repopulation of the root surface by progenitor cells, which have the potential for regeneration. Bioabsorbable type I Collagen membranes obtained from bovine tendon have been used in periodontal intrabony defects successfully when compared with flap debridement alone or with bone grafts alone. GTR membranes have been shown to regenerate the lost attachment apparatus when used in combination with autogenous bone grafts. [1]

The use of autogenous bone grafts is still considered as a gold standard in reconstructive procedures. These grafts can be used to regenerate lost bone in intraosseous defects, augment severely atrophic edentulous alveolar ridges, reconstruct alveolar defects in cleft palate patients. [2] The results of most studies show that the placement of bone grafts produce a more favorable probing pocket depth reduction, clinical attachment level (CAL) gain and increased bone fill as they may prevent collapse of the flap, thus enhancing wound stability and providing space for the regeneration process to occur. [3]

Meanwhile, the uses of alloplastic materials, which are synthetic, inorganic, biocompatible bone-graft substitutes, represent a possible alternative for the treatment of intrabony defects. Tom Driskell proposed the use of a ceramic form of β-tricalcium phosphate (β-TCP) to repair hard tissue avulsive wounds and orofacial fractures in the early 1970s. [4] The osteoconductive action of pure phase β-TCP has gained increased attention due to its porous micromorphology, interconnecting pore structure and full resorbability, which is synchronous with bone remodeling. Use of β-TCP has shown significant clinical improvements in grafted sites compared to non-grafted sites in controlled clinical studies. [5]

The combination of β-TCP and autogenous bone in the treatment of intraosseous periodontal defects has not been evaluated till date. The aim of this study was to compare the combination of β-TCP and autogenous bone in the treatment of intrabony periodontal defects with the established technique of GTR and autogenous bone.


  Materials and Methods Top


Patients for this study were selected from the Out-patient Department of Periodontics and Oral Implantology. A total of 12 patients were treated in the present study, which utilized a split-mouth design. The inclusion criteria were: (1) Patients of age group between 20 and 60 years. (2) In good systemic health. (3) Patients with moderate to severe chronic periodontitis with pocket depth ≥5 mm, having at least two intrabony defects on contralateral sides of same arch or in opposite arches. (4) Radiographic evidence of the intrabony defect. (5) Patients who had not received any type of periodontal therapy for the past 6 months. The exclusion criteria were: (1) Patients unable to perform routine oral hygiene procedures. (2) Patients with uncontrolled diabetes, on anticoagulant/immunosuppressive therapy and with any other systemic disease. (3) Patients who are known smokers. (4) Patients with known allergy to materials being used.

Informed consent was obtained from patients and ethical clearance was taken from the ethical committee prior to the commencement of the study.

12 three-wall periodontal defects designated as experimental site A were treated with β-TCP (Cerasorb® , Curasan AG, Kleinostheim, Germany) plus autogenous bone graft (test), compared with 12 contra-lateral defects treated with a bioabsorbable membrane (Biomend , Zimmer Dental, Carlsbad, USA) and autogenous bone graft (control), which were designated as experimental site B. Autogenous cortical bone was harvested using a bone scraper (MCT, Korea) [Figure 1].
Figure 1: Mini bone scraper-schematic illustration of harvesting autogenous bone graft

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Measurements

After the fabrication of a customized acrylic stent with a groove for better standardization, the probing depth (PD) and CAL were recorded at baseline and at 6 and 12 months after surgery. A William's graduated periodontal probe was used for all measurements [Figure 2]. Gingival recession was measured using the acrylic stent on the middle third of the buccal surface of the crown at baseline, 6 and 12 months post-operatively. Plaque index was measured at baseline, 1, 3, 6 and 12 months. [6] Radiographic bone fill was calculated by subtracting the distance from cemento-enamel junction to the base of the defect at 6 and 12 months from baseline measurements.
Figure 2: Groove on acrylic stent for better probe angulation during measurements-experimental site A

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Initial treatment and surgical protocol

At the first appointment, oral hygiene instructions were given to all patients. Following this, all the patients underwent full-mouth scaling and root planning. After adequate anesthesia, an intrasulcular incision was given and a full thickness flap was reflected [Figure 3]. A papilla preservation incision was done at sites where possible by giving a semilunar incision dipping apically at least 5 mm from the line angles of the teeth and the flap was reflected. [7] Degranulation, scaling and root planning were completed with gracey curettes (Hu-Friedy, USA). For the site A, bone graft was harvested from the adjacent area using a bone scraper and was mixed with β-TCP in 1:1 ratio [Figure 4] and [Figure 5]. This combined graft was then packed into the defect [Figure 6]. Flaps were sutured with horizontal mattress sutures [Figure 7]. A periodontal dressing was placed over the surgical wound. The same surgical protocol was followed for site B and a bioresorbable type-I collagen membrane (Biomend ) was placed over the autogenous bone graft material [Figure 8], [Figure 9], [Figure 10]. All the patients received post-operative instructions, including rinsing with 0.12% chlorhexidine (twice daily for 2 weeks) and antibiotic and anti-inflammatory medications for 1 week. The periodontal dressing was removed after 1 week and the patients were recalled at 1, 4 and 8 weeks for supragingival plaque removal. Patients were then recalled at 1, 3, 6 and 12 months post-surgery for recoding clinical and radiographic parameters.
Figure 3: Full thickness flap raised-experimental site A

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Figure 4: Harvesting autogenous bone graft-experimental site A

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Figure 5: Tricalcium phosphate and autogenous bone graft composite graft prepared

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Figure 6: Composite graft packed into defect-site A

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Figure 7: Experimental site A suturing done

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Figure 8: Experimental site B autogenous bone graft placed

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Figure 9: Experimental site B guided tissue regeneration membrane in place

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Figure 10: Experimental site B suturing done

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Interpretation of radiographs

Intra oral periapical radiographs were taken at baseline and 6 and 12 months post-operatively for each defect using long cone paralleling projection technique [Figure 11], [Figure 12], [Figure 13], [Figure 14], [Figure 15], [Figure 16]. Interpretation of radiographs was carried out by means of Image J® analysis software for linear measurements.
Figure 11: Radiograph at baseline-experimental site A

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Figure 12: Radiograph at 6 months-experimental site A

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Figure 13: Radiograph at 12 months-experimental site A

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Figure 14: Radiograph at baseline-experimental site B

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Figure 15: Radiograph at 6 months-experimental site B

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Figure 16: Radiograph at baseline-experimental site B

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Statistical analysis

All the clinical, radiological parameters recorded were evaluated using the following statistical analysis:

  1. For intragroup variations, Student paired t-test was performed.
  2. For comparison between the two groups/inter-group unpaired t-test was performed.
  3. For comparison of plaque index at different time intervals Wilcoxon matched pairs test was performed.



  Results Top


All 12 patients completed the 12-month study period. Both test and control group sites healed uneventfully. The soft tissue response, in both test and control groups, was excellent without any flap dehiscence or infection.

The mean plaque index score reduced to 52% at 1 month, 58% at 3 months, 57% at 6 months and 56% at 12 months when compared from baseline. All the mean values were statistically significant from baseline (P < 0.05)

Both test and control groups showed significant pocket depth reduction at 6 and 12 months when compared with baseline. The mean pocket depth reduction at the site A was of 3.91 ± 0.99 mm (49.47%) and 4.58 ± 1.08 mm (57.89%) at 6 and 12 months post-operatively and at site B was 4.08 ± 0.79 mm (52%) and 4.33 ± 1.37 (56%) at 6 and 12 months post-operatively. The difference between the groups was statistically not significant [Table 1].
Table 1: Comparison of site a and site b with respect to mean probing pocket depth scores at baseline, 6 months and 12 months by unpaired t-test

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At the site A, the baseline means CAL score was 8.50 ± 1.62 mm. At 6 months, it reduced to 4.66 ± 1.23 mm and at 12 months it reduced to 3.83 ± 0.93 mm with a mean reduction of 4.7 ± 1.43 mm (55%). At site B the baseline score was 7.91 ± 1.50 mm. It reduced to 4.0 ± 1.12 mm and 3.83 ± 0.9 mm at 6 and 12 months respectively with a mean reduction of 3.91 ± 0.79 mm (49.47%) at 6 months and 4.08 ± 1.37 mm (51.57%) at 12 months. All mean values at site A and B were statistically significant (P < 0.05) [Table 2] and [Figure 17].
Table 2: Comparison of site a and site b with respect to mean clinical attachment level scores at baseline, 6 months and 12 months by unpaired t-test

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Figure 17: Graphs showing mean defect fill and clinical attachment level

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On comparison between the sites, the mean difference in gingival recession at 6 and 12 months was 0.16 mm and 0.09 mm respectively, which were statistically not significant.

Radiographically, the bone fill at site A and at site B was recorded as 3.05 ± 1.2 mm (69%) and 3.26 ± 1.04 mm (71%), respectively, after 6 months, post-operatively. Similarly after 12 months bone fill at site A and at site B was 3.48 ± 1.22 mm (79%) and 3.84 ± 0.96 mm (82%) respectively. In both groups, mean radiographic bone fill was statistically significant at 6 and 12 months as compared from baseline [Table 3] and [Figure 17].
Table 3: Comparison of site a and site b with respect to percentage of defect fill at 6 and 12 months by unpaired t-test

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On intergroup comparison, the difference in defect fill was statistically not significant.


  Discussion Top


The traditional treatment procedures, which aim at treating periodontal disease, did not result in a true periodontal regeneration. To achieve this goal, extensive research has been done to develop more appropriate regenerative techniques.

A number of periodontal regenerative methods have been tried for regeneration of lost periodontal tissues, including root conditioning procedures, bone grafts and bone substitutes, GTR and biologic mediators.

Although there is no risk for cross-infection or immunogenic reaction with autogenous materials, their limited availability and the necessity of a donor site and thus, often a second surgical site, may limit their use. Use of mini bone scrapers is preferred in our study as autogenous bone can be collected from the same surgical site. The clinical results of Carraro et al. were more favorable with autogenous bone grafts as compared to open flap debridement alone in hundred infrabony pockets. [8] The efficacy of combinations of GTR membranes and autogenous bone grafts was compared by Chen et al. [9] It was found that autogenous bone graft and GTR has an increased bone content compared with GTR alone.

Autogenous bone grafts also have the potential disadvantage of involving a higher degree of resorption of the graft material which might adversely affect the bone fill achieved. Similar to xenografts and allograft materials, the major advantage of alloplasts over autogenous grafts is their easy availability. Thus, a trend towards the use of xenografts or allografts, which result in a greater amount of bone fill as a result of a lesser degree of resorption during the healing period, could be observed in bone augmentation procedures. [10] According to some histologic studies, healing may occur by encapsulation of these graft materials, with or without minimal bone formation. [11]

Autogenous grafts are osseoinductive and result in the formation of new bone faster than xenograft and alloplast materials. [12] It was suggested that a mixture of autogenous bone and these materials should be used to overcome the lack of osseoinductivity of xenografts and alloplastic materials and to reduce the amount of bone resorption observed with pure autogenous grafts. Limited clinical data exist on the use of composite grafts in the treatment of periodontal defects. Composite grafts demonstrated a degree of volume stability similar to xenogenic grafts during the healing period. [10] The penetration of host bone into the inner part of the graft material is related to the porosity of the material. Cortical bone is composed of a dense osteoid matrix and therefore, difficult to achieve angiogenesis. Combining β-TCP to cortical bone shavings obtained with a bone scraper may aid in the penetration of new blood vessels and also reduce the density of the cortical bone component of the graft. Stahl and Froum evaluated histologically the healing response to the placement of TCP implants and found that the gain in CAL is due to healing by long junctional epithelial adhesion. [13] Strub et al. in their human study compared TCP with allograft and found a measurable bone fill of 1.2 mm with TCP and 1.5 mm with allograft which was statistically not significant. [14] Metsger et al. reviewed the effective use of TCP ceramic as a graft-TCP, when used to repair marginal periodontal defects, which showed a degree of repair that was equal to or exceeded that obtained using autogenous bone. [15] The bone fill values in this study were higher than those from the study of Snyder et al. [16] (2.8 mm), Baldock [17] (1.8 mm) and Stavropoulos [18] (1.0 ± 0.7 mm). β-TCP was used for the treatment, showing that autogenous bone may have a supra-additive effect on the outcome of the treatment.

The reduction in mean PD in this study was in agreement with the study where a mean PD reduction of 4.5 mm was seen where β-TCP graft was used in the treatment of intrabony defects. [17]

In this study β-TCP and autogenous bone were used in combination as composite graft material. There have been no studies in the use of TCP and autogenous bone in combination for the treatment of intrabony defects. A autogenous bone to hydroxyapatite (HA) ratio varying from 1:1 to 1:2 has been recommended, to avoid excessive fibrous encapsulation of the HA granules. [19] As there is no information about the ideal ratio for autogenous bone β-TCP in the treatment of intrabony defects, a 1:1 ratio has been used in this study.

By using these grafts in combination, it was possible to evaluate if they had any synergistic effect when used together in the treatment of periodontal intrabony defects. β-TCP is prone to normal osteoclastic resorption. In combination with autogenous bone grafts, it can provide an additional stimulus for osteoconduction and can act as an expander. This can lead to a better bone regeneration by synergistic enhancement of osseoinduction and osseoconductive actions of auto and allografts. The advantages of this additive as supporting material for the particulate autogenous bone should be compared with the best possible results, which can be obtained with the use of autogenous bone grafts with the combination of GTR. Clinical research in periodontal regeneration has suggested that one of the most predictable techniques in improving the CALs and bone fill is by using a combination of a graft material and GTR. [20]

The use of various graft materials in combination with collagen membranes seems to improve clinical outcomes for periodontal osseous defects. McClain and Schallhorn showed that attachment levels were maintained more predictably in sites treated with a combined graft and GTR therapy than with GTR alone over a 5-year period. [21] Hence, GTR treatment was used to compare the outcome of β-TCP with autogenous bone in this study.

The pocket depth reduction and mean CAL gain in this study at site B is similar to what were obtained using bioabsorbable membranes along with autogenous bone graft in the study of Orsini et al. where there was a pocket depth reduction of 4.34 mm and a mean CAL gain of 3.58 mm. [22]


  Conclusion Top


Periodontal regeneration is a complex process, influenced by a multitude of surgical and mechanical factors as well as complex interactions between different cell types. The finding of this study indicates that the use of β-TCP in combination with autogenous bone graft material is beneficial for treatment of periodontal intrabony defects and is comparable to GTR with autogenous bone graft. There is a possible advantage of combined use of grafts and membranes in defects since composite grafts and as well as membrane composites may mutually increase mechanical and wound stability and thus, lead to a better treatment outcome. Long-term follow-up and larger sample size would further validate this study.

 
  References Top

1.Chen CC, Wang HL, Smith F, Glickman GN, Shyr Y, O'Neal RB. Evaluation of a collagen membrane with and without bone grafts in treating periodontal intrabony defects. J Periodontol 1995;66:838-47.  Back to cited text no. 1
    
2.Habal MB. Different forms of bone grafts. In: Habal MB, Reddi HD, editors. Bone Grafts and Bone Substitutes. Saunders: Philadelphia; 1992. p. 6-8.  Back to cited text no. 2
    
3.Reynolds MA, Aichelmann-Reidy ME, Branch-Mays GL, Gunsolley JC. The efficacy of bone replacement grafts in the treatment of periodontal osseous defects. A systematic review. Ann Periodontol 2003;8:227-65.  Back to cited text no. 3
    
4.Driskell TD, O'Hara MJ, Sheets HD Jr, Greene GW Jr, Natiella JR, Armitage J. Development of ceramic and ceramic composite devices for maxillofacial applications. J Biomed Mater Res 1972;6:345-61.  Back to cited text no. 4
    
5.Döri F, Arweiler N, Gera I, Sculean A. Clinical evaluation of an enamel matrix protein derivative combined with either a natural bone mineral or beta-tricalcium phosphate. J Periodontol 2005;76:2236-43.  Back to cited text no. 5
    
6.Silness J, Loe H. Periodontal disease in pregnancy. II. Correlation between oral hygiene and periodontal condtion. Acta Odontol Scand 1964;22:121-35.  Back to cited text no. 6
    
7.Takei HH, Han TJ, Carranza FA Jr, Kenney EB, Lekovic V. Flap technique for periodontal bone implants. Papilla preservation technique. J Periodontol 1985;56:204-10.  Back to cited text no. 7
    
8.Carraro JJ, Sznajder N, Alonso CA. Intraoral cancellous bone autografts in the treatment of infrabony pockets. J Clin Periodontol 1976;3:104-9.  Back to cited text no. 8
    
9.Chen ST, Darby IB, Adams GG, Reynolds EC. A prospective clinical study of bone augmentation techniques at immediate implants. Clin Oral Implants Res 2005;16:176-84.  Back to cited text no. 9
    
10.McAllister BS, Margolin MD, Cogan AG, Buck D, Hollinger JO, Lynch SE. Eighteen-month radiographic and histologic evaluation of sinus grafting with anorganic bovine bone in the chimpanzee. Int J Oral Maxillofac Implants 1999;14:361-8.  Back to cited text no. 10
    
11.Saffar JL, Colombier ML, Detienville R. Bone formation in tricalcium phosphate-filled periodontal intrabony lesions. Histological observations in humans. J Periodontol 1990;61:209-16.  Back to cited text no. 11
    
12.Lohmann CH, Andreacchio D, Köster G, Carnes DL Jr, Cochran DL, Dean DD, et al. Tissue response and osteoinduction of human bone grafts in vivo. Arch Orthop Trauma Surg 2001;121:583-90.  Back to cited text no. 12
    
13.Stahl SS, Froum S. Histological evaluation of human intraosseous healing responses to the placement of tricalcium phosphate ceramic implants. I. Three to eight months. J Periodontol 1986;57:211-7.  Back to cited text no. 13
    
14.Strub JR, Gaberthüel TW, Firestone AR. Comparison of tricalcium phosphate and frozen allogenic bone implants in man. J Periodontol 1979;50:624-9.  Back to cited text no. 14
    
15.Metsger DS, Driskell TD, Paulsrud JR. Tricalcium phosphate ceramic - A resorbable bone implant: Review and current status. J Am Dent Assoc 1982;105:1035-8.  Back to cited text no. 15
    
16.Snyder AJ, Levin MP, Cutright DE. Alloplastic implants of tricalcium phosphate ceramic in human periodontal osseous defects. J Periodontol 1984;55:273-7.  Back to cited text no. 16
    
17.Baldock WT, Hutchens LH Jr, McFall WT Jr, Simpson DM. An evaluation of tricalcium phosphate implants in human periodontal osseous defects of two patients. J Periodontol 1985;56:1-7.  Back to cited text no. 17
    
18.Stavropoulos A, Windisch P, Szendröi-Kiss D, Peter R, Gera I, Sculean A. Clinical and histologic evaluation of granular Beta-tricalcium phosphate for the treatment of human intrabony periodontal defects: A report on five cases. J Periodontol 2010;81:325-34.  Back to cited text no. 18
    
19.Cobb CM, Eick JD, Barker BF, Mosby EL, Hiatt WR. Restoration of mandibular continuity defects using combinations of hydroxylapatite and autogenous bone: Microscopic observations. J Oral Maxillofac Surg 1990;48:268-75.  Back to cited text no. 19
    
20.Cortellini P, Bowers GM. Periodontal regeneration of intrabony defects: An evidence-based treatment approach. Int J Periodontics Restorative Dent 1995;15:128-45.  Back to cited text no. 20
    
21.McClain PK, Schallhorn RG. Long-term assessment of combined osseous composite grafting, root conditioning, and guided tissue regeneration. Int J Periodontics Restorative Dent 1993;13:9-27.  Back to cited text no. 21
    
22.Orsini M, Orsini G, Benlloch D, Aranda JJ, Lazaro P, Sanz M, et al. Comparison of calcium sulfate and autogenous bone graft to bioabsorbable membranes plus autogenous bone graft in the treatment of intrabony periodontal defects: A split-mouth study. J Periodontol 2001;72:296-302.  Back to cited text no. 22
    


    Figures

  [Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5], [Figure 6], [Figure 7], [Figure 8], [Figure 9], [Figure 10], [Figure 11], [Figure 12], [Figure 13], [Figure 14], [Figure 15], [Figure 16], [Figure 17]
 
 
    Tables

  [Table 1], [Table 2], [Table 3]



 

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