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Table of Contents   
ORIGINAL RESEARCH  
Year : 2022  |  Volume : 33  |  Issue : 2  |  Page : 152-157
Evaluation of biphasic hydroxapatite and β-tricalcium phosphate as a bone graft material in the treatment of periodontal vertical bony defects – A clinical and digital radiological measurement study


1 Department of Periodontology, Eklavya Dental College and Hospital, Kotputli, Rajasthan, India
2 Department of Oral Medicine and Radiology, Bhojia Dental College and Hospital, Baddi, Himachal Pradesh, India
3 Department of Orthodontics, Resident, Georgia School of Orthodontics, Georgia, USA
4 Department of Oral Medicine and Radiology, SCB Dental College, Cuttack, Odisha, India
5 Department of Oral Pathology and Microbiology, Institute of Dental Sciences, Bhubaneswar, Odisha, India

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Date of Submission09-Mar-2019
Date of Decision25-May-2022
Date of Acceptance04-Jul-2022
Date of Web Publication13-Oct-2022
 

   Abstract 


Aims and Objective: The present study aimed to evaluate 2 bone graft materials, that is, biphasic hydroxyapatite and β-tricalcium phosphate, in the treatment of periodontal vertical bony defects. In term of attachment level, probing depth and radiographic bone level changes. Also, a new digital method of radiographic assessment was used for measurement of vertical bone defect. Material and Methods: Ten subjects with periodontitis and having two or more vertical bony defects were enrolled in the study. Patients were classified randomly into 2 groups. Group I consisted of the experimental site where defect was filled with biphasic hydroxyapatite and β-tricalcium phosphate graft and Group II consisted of control site where only the open flap debridement (OFD) was carried out. Clinical parameters were evaluated at baseline, 3 and 6 months; Radiographs were taken at baseline and 6 months after surgery. Results: Overall, by the end of 6 months, biphasic hydroxyapatite and β-tricalcium phosphate and OFD treatment groups exhibited a significant reduction in probing depth almost by 75% and gain in clinical attachment level at follow-up. In the biphasic hydroxyapatite and β-tricalcium phosphate group, radiographic bone level gain appeared to be greater than in the OFD group. Conclusion: In the present study, biphasic hydroxyapatite and β-tricalcium phosphate have shown promising results and have showed reduction in probing depth, a resolution of osseous defects and gain in clinical attachment level when compared to open flap debridement.

Keywords: β-tricalcium phosphate, hydroxyapatite, open flap debridement, vertical defect

How to cite this article:
Gupta AK, Arora KS, Aggarwal P, Kaur K, Mohapatra S, Pareek S. Evaluation of biphasic hydroxapatite and β-tricalcium phosphate as a bone graft material in the treatment of periodontal vertical bony defects – A clinical and digital radiological measurement study. Indian J Dent Res 2022;33:152-7

How to cite this URL:
Gupta AK, Arora KS, Aggarwal P, Kaur K, Mohapatra S, Pareek S. Evaluation of biphasic hydroxapatite and β-tricalcium phosphate as a bone graft material in the treatment of periodontal vertical bony defects – A clinical and digital radiological measurement study. Indian J Dent Res [serial online] 2022 [cited 2022 Nov 29];33:152-7. Available from: https://www.ijdr.in/text.asp?2022/33/2/152/358442



   Introduction Top


Periodontitis is the most prevalent disease worldwide in term of periodontal disease. It is an infectious disease involving the gingival tissue along with involvement of bone which is the primary cause of tooth loss.[1] Periodontal therapy aims to eliminate inflammation and arrest the destruction of soft tissue and bone and facilitate the regeneration of the lost tissue if possible.[2]

Conventional therapies are primarily focused on scaling and root planing, curettage, gingivectomy, surgical access flaps and resective osseous surgeries. These methods induce repair by formation of a long junctional epithelium.[3] But, with changing trends there has been a shift from the conventional methods of treatment and now the concept of regeneration is being opted in practice.[4] Regenerative therapy includes the use of open flap curettage with root planing, chemical root biomodification, guided tissue regeneration with barrier membranes and various bone grafts.[5]

In mid 1970s, several bone regenerative materials have been tested including calcium phosphates, which has excellent tissue compatibility and without eliciting inflammation or foreign body response. Two types of calcium phosphate ceramics have been used, which are hydroxyapatite and tricalcium phosphate.[6],[7]

Hydroxyapatite has calcium to phosphate ratio of 1.67, whereas tricalcium phosphate has a ratio of 1.5. The former is generally non-bioresorbable and the latter is partially resorbable. Hydroxyapatite is the principal constituent of bone and teeth and has ability to induce bone growth when used as graft material and its density determine strength of graft and extent of vascular growth. On the other hand, β-tricalcium phosphate biodegrades 10-20 times faster but in an unpredictable way. The results are superior remodelling than hydroxyapatite during final stage of bone formation.[5],[8]

Ossifi (equinox medical technologies, Holland) (synthetic hydroxyapatite and beta tricalcium phosphate) is a biphasic calcium phosphate consisting of hydoxyapatite and β-tricalcium phosphate in a biocompatible weight % ratio of 70:30 (approximately), which is also believed to be non-toxic, non-resorbable, non-inflammatory and bioactive. Moreover, it causes no immunological foreign body or irritating response and has excellent osteoconductive ability. Also, the number of studies conducted using this material is very limited. Thus, the present clinical and radiographic study aimed to evaluate this bone graft materials, that is, hydoxyapatite and β-tricalcium phosphate in the treatment of vertical bony defects.


   Material and Methods Top


The present study was carried out after approval of the ethical committee of Rajasthan Dental College and Hospital, Jaipur vide letter no. RDCH/ST/2014/314 dated 03.07.2014. After discussion and approval from a statistician, 10 patients (twenty defects) diagnosed with chronic generalized periodontitis having two or more vertical defects were selected for this study from the out-patient department. The patients diagnosed as having chronic periodontitis with at least two periodontal pockets with probing depth of ≥4 mm and radiographic evidence of vertical bone loss, patients with good general health and without any history of systemic diseases, and patients with no endodontic or periapical pathology of the involved teeth and mobility not greater than grade II were included in the study. Patients who showed unacceptable oral hygiene, pregnant or lactating women, heavy smokers (more than 20 cigarettes per day), patients with systemically compromised status and patients who were otherwise contraindicated for surgery were excluded from the study.

A written signed informed consent was taken from the patient, explaining the nature of the study and surgical procedure. First, the clinical parameters at baseline were assessed using Plaque index (Silness and Loe, 1964) and Gingival bleeding index (Loe and Silness, 1963). The probing pocket depth was measured using UNC-15 probe with occlusal stent, the clinical attachment level was measured using UNC-15 probe with occlusal stent and Intraoral Periapical radiographs (long cone paralleling technique).

Secondly, the radiographic parameters were assessed by intraoral periapical radiographs using Kodak RVG 5100 which were taken at baseline and six months. The Rinn XCP-ORA holding paralleling device (Dentsply) was used to expose the radiographs. The images were stored in JPEG format and were displayed on the monitor at 5x magnification using Adobe Photoshop 7 computer software. 0.5-mm grid was made on JPEG images, and all linear measurements were made using Auto- CAD 2006 software.

Pre-surgical protocol consisted of phase 1 therapy and the maintenance phase. Following an initial examination and treatment planing discussion, all the selected patients subjected to full mouth scaling, root planing and curettage with oral hygiene instructions. Occlusal adjustment was carried out wherever indicated. Re-evaluation was done after initial therapy. Routine haematological examination and serological examination including screening for HIV and Hepatitis-B was also carried out. All the sites were subjected to record the clinical and radiographic parameters.

During the surgical phase the selected sites were randomly assigned to either experimental [Figure 1] or control site [Figure 2]. The defect site was exposed by reflection of full thickness mucoperiosteal flap and were cleared of granulation tissue followed by thorough root planing and irrigation with normal saline. At the experimental site, the defect was filled with Ossify particles size (0.25-1.0 mm). The material was placed from the base of the defect coronally to the approximate level of the crest or the remaining osseous walls. The operative site was closed with 4-0 black silk sutures and protected with a non-eugenol dressing (Coe-Pack). The control sites were left unfilled after surgical debridement and thorough root planing and irrigation of surgical wound with normal saline. The mucoperiosteal flaps were repositioned and secured in place using black braided (4-0) interrupted silk sutures (Mersilk) to obtain primary closure of the interdental space and protected with a non-eugenol dressing (Coe-Pack). All patients were prescribed an analgesic Diclofenac sodium 50 mg twice a day and Amoxycillin 500 mg antibiotic thrice a day for 5 days.
Figure 1: (a) Probing pocket depth at baseline; (b) Sulcular incision with No. 12 BP blade; (c) Defect distal aspect of #tooth43; (d) Site after placement of graft; (e) Interrupted sutures placed; (f) Placement of Peridontal pack; (g) Probing pocket depth at 6 months; (h) Pre-operative radiograph; (i) Post-operative radiograph (at 6 months)

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Figure 2: (a) Probing pocket depth at baseline; (b) Sulcular incision with No. 12 BP blade; (c) Defect w.r.t. distal aspect of #tooth 36; (d) Interrupted sutures given; (e) Placement of Periodontal pack; (f) Probing pocket depth at 6 months; (g) Pre-operative radiograph; (h) Post-operative radiograph (at 6 months)

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Post-surgery, the patient was recalled after 24 hours to check for any post-surgical complication. One week following surgery, the dressing and sutures were removed, and surgical site was irrigated thoroughly with saline. Symptoms regarding discomfort, pain, and sensitivity were asked from the patient. If any sign of swelling, infection, particle migration, flap displacement, hematoma, and necrosis was noted, the dressing was replaced for another one week. Patients were instructed to rinse with Chlorhexidine (0.2%) mouthwash twice daily for another week. Recall appointments were made at 3 months and 6 months. At each visit, oral hygiene instructions were reinforced and the surgical sites were professionally irrigated with normal saline. Clinical parameters (plaque index, gingival index, probing pocket depth, clinical attachment level) were repeated for both control and experimental sites similar to previous presurgical measurement. At the end of six months post therapy patients were also evaluated radiographically.

The data obtained was collected using Microsoft Excel (Microsoft Office, Illinois, USA), which was subject to statistical analysis using Statistical Package for Social Sciences (SPSS version 19).


   Results Top


Out of total 10 subjects, 6 were males with a mean and standard deviation of 33 ± 3.225 and a median of 32 and 4 were females with a mean and standard deviation of 35.5 ± 5.26 and a median of 36.

Wilcoxon Signed Rank Test was applied for comparison of plaque index values at different intervals. Comparative analysis of baseline and 3 months revealed significant difference between both. Comparative analysis of baseline and after 6-month also revealed significant difference between both [Table 1].
Table 1: Plaque Index (Silness and Loe, 1964) and Gingival Bleeding Index (Loe and Silness, 1963)

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Wilcoxon Signed Rank Test was used for comparison of gingival index values which revealed significant difference between baseline and 3 months and baseline and 6 months [Table 1].

Probing pocket depth

  1. Intragroup observations: Paired t-test was applied for intragroup comparison of probing pocket depth for experimental site and control site. A statistically highly significant reduction was seen in probing pocket depth in both the groups when the baseline was compared with healing after 3 and 6 months, respectively. The Mean and Standard Deviation for experimental group at Baseline, 3 months and 6 months was 7.1 ± 1.729, 4.8 ± 1.033 and 3.8 ± 0.9189, respectively. The Mean and Standard Deviation for control group at Baseline, 3 months and 6 months was 6 ± 1.155, 4.5 ± 0.9718 and 4 ± 0.6667, respectively.
  2. Intergroup observations: The intergroup comparison of experimental and control site was carried out using Paired t-test which indicated a non-significant difference between the 2 site after 3 months. But, after 6 months, the values indicated a significant difference (p < 0.05).


However, overall in the experimental group, the decrease in probing depth between baseline and six months postoperative was 44.70% as compared to control group which showed a decrease of 31.37%. Thus, comparing the experimental and control group, we comment that the decrease in probing depth in control group was less than experimental group which was also statistically significant (p < 0.05).

Clinical attachment level

  1. Intragroup observations: Paired t-test was applied for intragroup comparison of clinical attachment levels for both experimental site and control site. For control site a statistically highly significant improvement was seen in clinical attachment when baseline was compared with healing after 3 and 6 months, respectively. Similarly, for the experimental site a highly significant statistical value was recorded and there was significant improvement in clinical attachment at 3- and 6-month intervals. The Mean and Standard Deviation for experimental group at Baseline, 3 months and 6 months was 7.9 ± 2.846, 5.6 ± 2.066 and 4.6 ± 1.838, respectively. The Mean and Standard Deviation for control group at Baseline, 3 months and 6 months was 5.9 ± 1.287, 4.5 ± 0.9718 and 4 ± 0.6667, respectively.
  2. Intergroup observation: The intergroup comparison of experimental and control site was carried out using Unpaired t-test. After 3 months interval a statistically non-significant difference was observed between the 2 sites. But, at an interval of 6 months a significant difference was observed.


Thus, comparing the control and experimental group, the gain in clinical attachment from baseline to six months postoperatively was found to be 41.07% for experimental group whereas for control group it was 29.87% only. Thus, we can comment that the gain in clinical attachment level in experimental group was more than the control group which was statistically significant (p < 0.042).

Radiographic measurements

  1. Cemento-enamel Junction-Bone Defect (CEJ-BD): The CEJ-BD evaluation was carried out using a Paired t-test which revealed a statistically significant value for both the control and experimental site [Table 2].
  2. Linear Bone Growth: The linear bone growth was evaluated using an Unpaired t-test which indicated a significant difference between the 2 sites (p < 0.002) [Table 3].
  3. Percentage Bone Fill: The comparison between the control and experimental site was done using Unpaired t-test which indicated a highly significant difference between the two.
Table 2: Mean Radiographic Cemento-Enamel Junction to Bone Defect (CEJ-BD) measurement in Control and Experimental Site

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Table 3: Mean radiographic Linear Bone Growth and Percentage Bone Fill (%BF) in Control and Experimental Site

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On analysis of all the above findings, it was observed that OssifyTM showed better results than the open flap debridement alone, when evaluated both clinically and radiographically.


   Discussion Top


Periodontal diseases result in loss of attachment apparatus and periodontal therapy aims in regeneration of this attachment including formation of cementum, periodontal ligaments and alveolar bone. In a quest to achieve attachment, various implant materials have been investigated, wherein studies indicate autogenous bone grafts are gold standard for grafting procedures, but with limited use because of difficulty in procurement and need for additional surgery.[7],[9] Thus, alloplastic materials were searched as a substitute which are biocompatible, bio-degradable, and possess good osteogenic potential.[10] Synthetic hydroxyapatite is the most biocompatible substance known for use in hard tissue implantations. They can become functionally integrated with natural bone with no fibrous tissue encapsulation and cause no alteration of bone mineralization process.[11],[12],[13],[14]

Ossify has shown to fulfil the requirements for synthetic biomaterials being biocompatible, non-toxic, resorbable, non-inflammatory, cause no immunological, foreign-body, or irritating response and have excellent osteoconductive ability. It has also shown definite excellence than other bone graft materials or flap debridement alone in some previous studies.[11],[15],[16],[17]

There was a statistically significant reduction in the Plaque Scores from baseline to 3 months and 6 months in both the experimental group and the control group. This reduction can be attributed to the rigorous oral hygiene maintenance regime and regular follow up visits and reinforcement of oral hygiene instructions followed by the patients throughout the study period. These results are comparable to the previous studies done by Oreamuno et al. 1990[18] and Bansal et al. 2014.[19] On the contrary, a study conducted by Dayashankar et al.[20] 2017 showed that there was a significant reduction in plaque scores in test groups and no significant results were obtained in the control group.

There was a statistically significant reduction in the gingival index scores from baseline to 3 months and 6 months in both the Experimental and the Control groups. The definite reductions exhibited could be due to surgery and frequent supportive therapy provided. These results are comparable to the previous studies done by Bansal et al. 2014.[19] and Dayashankar et al. 2017.[20]

Statistically significant reduction in the probing depths was observed in both the experimental and the control groups. However, the experimental group demonstrated more reduction of the probing depths compared to the control group at 6 months interval. Decrease in probing depth in experimental site between baseline and six months postoperative was 44.70% as compared to control group which showed a decrease of 31.37%. This decrease in probing depth in control group was less than experimental group which was statistically significant also. This compares favourably with the studies done earlier by Kreji et al. in 1987, Nery et al. in 1990, Stahl and Forum in 1991, Galgut in 1992, Yukna et al. in 2002, Bansal et al. 2014 and Dayashankar et al. 2017.[12],[13],[14],[15],[19],[20] However, in a similar study conducted by Shah et al. 2021[4] a significant decrease in Probing Pocket Depth was observed when compared to the control group.

Our study demonstrated a statistically significant increased gain in the clinical attachment levels in both the experimental and the control groups. The comparable attachment gain in the Control group could be attributed to the formation of the long junctional epithelium instead of increased bone fill and tissue repair as seen in the experimental group. However, the nature of this attachment could not be elicited as it required histologic evaluation. This finding is consistent with the studies of Bowen et al. in 1989, Nery et al. in 1990, Stahl and Forum in 1991, Galgut in 1992, Yukna et al. in 2002, Bansal et al. 2014, Shah et al. 2021.[4],[12],[14],[15],[19]

Radiographic parameters included linear bone growth and percentage of bone fill. Linear Bone growth (LBG) = (CEJ to base of defect at 6 months) – (CEJ to base of defect at baseline) is the amount of linear defect depth fill from baseline to 6 months post-operatively. Comparative analysis of mean percentage change in defect fill for both the sites revealed about 42.57% bone fill for experimental site, whereas in control site 20.04% of bone fill was observed, thus showing that the experimental site had higher percentage of defect fill than control site which was statistically significant. These findings are consistent with that of Meffert Roland et al. in 1985, Nery et al. in 1990, Stahl and Forum in 1990, Galgut in 1992 and Yukna in 2002 and Bansal et al. 2014 and Dayashankar et al. 2017.[11],[12],[14],[15],[19],[20]

Overall, the results indicated that bone graft biphasic hydroxyapatite and β-tricalcium phosphate (Ossify) produced a more favourable clinical attachment level gain, probing pocket depth reduction and increased bone fill when compared with open flap debridement alone.


   Conclusion Top


Although this new combination of synthetic hydroxyapatite and β-tricalcium phosphate (Ossify™) has shown promising results on clinical and radiographic evaluation it would be inappropriate to draw definite conclusions from the present study without histological examination. Further long-term studies are required to clarify the beneficial effects of Ossify in treating periodontal intrabony defects.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.



 
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Shah AG, Prabhu K S, Janitha S. Clinical evaluation of oily calcium hydroxide suspension alone and in combination with β-tricalcium phosphate in the treatment of periodontal intrabony defects. Indian J Multidiscip Dent 2019;9:70-6.  Back to cited text no. 4
  [Full text]  
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Galgut PN, Waite JM, Brook Shaw JP, Kingston CP. A 4-year controlled clinical study into the use of a ceramic hydroxyapatite implant material for the treatment of periodontal bone defects. J Clin Periodontol 1992:19;570-7.  Back to cited text no. 12
    
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Kreji CB, Bissuda NF, Farah C and Geenwell H. clinical evaluation of porous and non –porous hydroxyapatite in the treatment of human periodontal bony defects. J Periodontol 1987;58:521-8.  Back to cited text no. 13
    
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Stahl SS, Froum SJ, Tarnow D. Human clinical and histologic responses to the placement of HTR polymer particles in 11 intrabony lesions. J Periodontol 1990;62:269-74.  Back to cited text no. 14
    
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Nery EB, Lee KK, Czajkowski S, Dooner JJ, Duggan M, Ellinger RF et al. A veterans administration cooperative study of biphasic calcium phosphate ceramic in periodontal osseous defects. J Periodontol 1990;61:737-44.  Back to cited text no. 15
    
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Aichelmann- Reidy ME, Yukna RA. Bone replacement grafts- the bone substitutes. Dent Clin of North Am 1998;42:491-504.  Back to cited text no. 16
    
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Kohad RM, Shetty S, Yeltiwar RK, Vaidya SN. A new synthetic hydroxyapatite – the right answer to bone regeneration. J Ind Soc Periodontol 2001;4:6-11.  Back to cited text no. 17
    
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19.
Bansal R, Patil Sudhir, Chaubey KK, Thakur RK, Goyel P. Clinical evaluation of hydroxyapatite and β-tricalcium phosphate composite graft in the treatment of intrabony periodontal defect: A clinico-radiographic study. J Indian Soc Periodontol 2014;18:610-7.  Back to cited text no. 19
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20.
Dayashankar CP, Deepika PC, Siddaramaiah B. Clinical and radiographic evaluation of citric acid-based nano hydroxyapatite composite graft in the regeneration of intrabony defect – A randomized control trial. Contemp Clin Dent 2017;8:380-6.  Back to cited text no. 20
[PUBMED]  [Full text]  

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DOI: 10.4103/ijdr.IJDR_234_19

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