Randomized Controlled Study on Effect of Concentrated Growth Factors on Crestal Bone Levels and Peri-implant Bone Density in Dental Implants

Abstract

Introduction:

Modern dentistry aims to restore the comfort and health of the stomatognathic system. Dental implants have emerged as a promising option for this purpose. Concentrated growth factors (CGFs) have been suggested to enhance the healing of bone grafts and enhance the integration of implants into the bone. Growth factors are proteins which regulate the complex process of wound healing. They play an important role in cell migration, cell proliferation, and angiogenesis in the tissue regeneration phase. CGF was first developed by Sacco in 2006. It can be used as a barrier membrane to accelerate soft-tissue healing. CGF does not require any chemical or anticoagulants, and hence, it is free from viral transmission diseases. Crestal bone levels, peri-implant bone density, bleeding, probing depth, mobility, occlusion factors, restoration adequacy, radiographic images, oral hygiene, and patient health status are some of the important parameters for determining longevity of success rates in implant dentistry. This study will assess the peri-implant bone density and crestal bone levels with and without the use of CGF.

Aim:

To evaluate the effect of CGFs on peri-implant bone density and in the preservation of crestal bone levels around dental implants.

Materials and Methods:

• Sampling procedure: Random selection of population (Sealed envelope method)

• Number of groups: Two-Control group (Group 1) and Experimental group (Group 2)

• Sample size: 20

For Group 2, implants were placed with CGF. For Group 1, implants were placed without CGF. The peri-implant bone density and bone levels were measured by Digora and signora software.

Results:

The mean crestal bone loss on the mesial aspect of implants placed in Group 2 is 0.294 mm and Group 1 is 0.345 mm, and the mean crestal bone loss on the distal aspect of implants placed in Group 2 is 0.320 mm and in Group 1 is 0.331 mm. There are no many significant differences on mesial and distal aspects around implants between the two groups Intragroup comparison of bone density values in Group 1 shows the mean difference from baseline to 1 month is 0.6, and after three and 6 months periods are 1.1 and 1.1, respectively, which indicates not much significant improvement in bone density values in Group 1. Intergroup comparison shows a significant difference between both the groups starting from as early as the 1^st month.

Conclusion:

The results of this study indicate that CGF is significantly better in the regeneration of bone around the implants when comparing with nonCGF groups. Although CGF showed improvement in bone formation, there are no many differences in crestal bone level changes on mesial and distal sides of the implants between the two groups.

INTRODUCTION

Modern dentistry aims to restore the comfort and health of the stomatognathic system. Dental implants have emerged as a promising option for this purpose.[1]

A dental implant is a prosthetic device made of alloplastic material(s) implanted into the oral tissues beneath the mucosal or/and periosteal layer, and on/or within the bone to provide retention and support for a fixed or removable dental prosthesis; a substance that is placed into or/and on the jaw bone to support a fixed or removable dental prosthesis.

A typical implant consists of a titanium screw (resembling a tooth root) with a roughened or smooth surface. The majority of dental implants are made out of commercially pure titanium which is available in four grades depending upon the amount of carbon and iron contained. More recently, grade 5 titanium is being used increasingly. Grade 5 Titanium, Titanium 6Al-4V alloy (signifying the titanium alloy containing 6% Aluminum and 4% vanadium alloy) is believed to offer similar osseointegration levels as commercially pure titanium. Ti-6Al-4V alloy offers better tensile strength and fracture resistance. Implant surfaces may be modified by plasma spraying, anodizing, etching, or sandblasting to improve the osseointegration potential of the implant.[2]

Osseointegration or osteointegration refers to a direct bone-to-metal interface without the interposition of nonbone tissue. This concept has been described by Branemark, as consisting of a highly differentiated tissue making “a direct structural and functional connection between ordered, living bone, and the surface of a load-carrying implant.”[3]

Professor Per-Ingvar Branemark (1952) working in the laboratory of the vital microscopy, University of Goteberg, Sweden, accidentally discovered that titanium bonded well with bone; a phenomenon which was later termed as osseointegration.[4]

The osseointegration of dental implants is critically dependent on their surface properties.[5]

Growth factors

Growth factors are proteins which regulate the complex processes of wound healing.[6] Growth factors play a main role on cell migration, cell proliferation, and angiogenesis in the tissue regeneration phase.[7]

Concentrated growth factors (CGFs) have been suggested to enhance the healing of bone grafts and enhance the integration of implants into the bone. CGF was first developed by Sacco in 2006.[7]

The four main categories identified as parameters for success related to the implant level, peri-implant soft-tissue level, prosthesis level, and the patient's subjective assessment.[8] The aim of this study was to assess the peri-implant bone density and crestal bone levels around implants with and without the application of CGFs.

MATERIALS AND METHODS

IRB approval

Before the start of the study, the methodology was presented to the IRB, and approval was obtained.

Reg No/Date: 2014-MD-Brl-VEN-02; 14.3.2015

Sampling procedure: Random selection of population (sealed envelope method)

Number of groups: Two-control group (Group 1) and experimental group (Group 2)

Sample size: 20

Inclusion criteria

• Subjects with missing teeth

• Physically healthy individuals (ASA I/II)

• Subjects who had given signed informed consent [Figure 1].

Figure 1.

Implant patient

Exclusion criteria

• Medically compromised individuals

• Subjects with medication known to interfere with wound and bone healing.

Implant placement protocol: (experimental)

Osteotomy preparation was done following standard surgical protocols with adequate irrigation. For this group, implants were placed with CGF [Figure 2].

Figure 2.

Implant placement procedure

Concentrated growth factor production technique

CGF is produced by collecting the patient's blood into 10 ml test tubes [Figure 3], which are immediately centrifuged with the MEDIFUGE SILFRADENT centrifuge [Figure 4]. Up to 8 test tubes can be taken at any one time, with no need to add any other substances, and single centrifugation will yield 3 fractions in each test tube. The coagulation may be used in the form of a membrane, by compressing it, or in fragments created by fragmenting the coagulation itself [Figures 5 and 6].

Figure 3.

Withdrawing blood for concentrated growth factor

Figure 4.

Medifuge centrifug

Figure 5.

Concentrated growth factors

Figure 6.

CGF in centrifuged blood

Once filled, the test tubes are quickly placed into the rotor of the Medifuge (Silfradent, Italy) [Figure 4] centrifuge accelerator, without shaking them.

Implant placement procedure

Before the surgery, careful and detailed planning was done to identify vital structures such as the inferior alveolar nerve or the sinus, as well as the shape and dimensions of the bone to properly orient the implants for the most predictable outcome. Two-dimensional radiographs, such as orthopantomography and periapical radiographs were made before the surgery. The placement of a dental implant requires preparation of the bone using precision drills with highly regulated speed and torque to prevent overheating or putting too much pressure on the bone [Figure 7]. It is important for the patient to follow postoperative instructions closely to maximize implant success [Figure 8].

Figure 7.

Armamentarium

Figure 8.

After implant placement

Post surgical and recall level radiographs

Orthopantomogram and intraoral periapical radiographs using radiovisiography were taken after each implant placement. Orthopantomogram and radiographs were taken at the baseline, after 1^st month, 3^rd, and 6^th months.

Data collection phase

The peri-implant bone density and crestal bone levels were measured at 0, 1^st, 3^rd, and 6^th months of implant placement.

Analysis of bone density

The peri-implant bone density was assessed using DIGORA software [Figure 9]. Digora software has increased sensitivity in the detection of bone changes noninvasively.[9] Four digitalized OPG are taken at prescheduled intervals. Nine points were marked around implants (Mesially four points, distally four points, and apically one point). Mesial four points M1, M2, M3, M4 were placed in the precise positions between thread no. 2 and 3, 4 and 5, 6 and 7, and 8 and 9 of the implant on the mesial aspect and Distal four points D1, D2, D3, and D4 were placed in similar points on the distal aspect and point A was marked 1 mm apically from the apex of the implant. The images were compared at different intervals using DIGORA Software. The radiographic density differences between each interval were evaluated and analyzed.

Figure 9.

Measurement of bone density by Digora software

Analysis of crestal bone level

The crestal bone levels were assessed using digitalized Orthopantomogram (Signora) [Figures 10 and 11]. The top surface of the implant was used as the reference line and the first bone-implant contact on mesial and distal aspects was used as the bone level indicator.[10] Perpendicular lines were dropped from the reference line and the bone level on the mesial and distal sides of the implant, and the distance was measured to the nearest 0.01 mm with the image tool (Signora). The readings were recorded at baseline, 1 month, 3 months, and 6 months for all groups. All measurements were performed by an instructed dental student and checked by another investigator under the supervision of the main investigator of the study. The mean bone loss was calculated. These readings were then analyzed statistically.

Figure 10.

Measurement of crestal bone (maxilla)

Figure 11.

Measurement of crestal bone (mandible)

Statistical analysis

In this study, Student's t-test (paired and unpaired) was used. Paired t-test is used to measure at two different points from the data collected from subjects, whereas unpaired t-test was used to measure from two different and independent subjects. The readings obtained were analyzed by SPSS software (Version 19.0) CHICAGO, United States of America, and paired and unpaired t-tests were used to evaluate the intra- and inter-group differences in bone density around implants and unpaired t-test was used to compare the differences between two groups in crestal bone levels. The values of periimplant bone density were compared with baseline at 1 month, at 3 months, and at 6 months within the same group; and between groups, and crestal bone level values were compared at baseline, 1 month, 3 months, and 6 months between groups. The P value was taken significantly at P < 0.05 and highly significant at P < 0.01.

RESULTS

Out of the twenty implants which were placed for the study, 10 implants (50%) were placed without CGFs (Group 1) and 10 implants were placed with CGFs (Group 2). The results were tabulated and statistically analyzed.

Differences in the crestal bone levels were not statistically significant at all the time intervals (From baseline to 1^st month, 3^rd month, and 6^th month) [Tables 1 and 2]. Inter-group comparison (Group 1– without CGF, Group 2– with CGF) of mean bone level for Group 1 from mesial baseline to 1^st month, 3^rd month_, and 6^th month were 0.120, 0.213, and 0.345, respectively, and Group 2 at 1^st, 3^rd month_, and 6^th month were 0.074, 0.171, and 0.294, respectively [Table 3]. Mean bone level for Group I from distal baseline to 1^st month, 3^rd, and 6^th months were 0.133,0.248, and 0.331, respectively and Group 2 at 1^st, 3^rd, and 6^th months were 0.100, 0.222, and. 320, respectively [Table 3]. On analyzing the results statistically, there was no statistically significant difference between the two groups [Table 4].

Table 1.

Crestal Bone Values and Differences at Baseline, 1^st , 3^rd & 6^th Month ( Without CGF)

Implant without CGF (Group 1) ( readings in mm)
Baseline readin		At 1st month		At 3rd month		At 6th month		Diff btwn baseline and 1st month		Diff btwn baseline and 3rd month		Diff btwn baseline and 6th month
Mesial	Distal	Mesial	Distal	Mesial	Distal	Mesial	Distal	Mesial	Distal	Mesial	Distal	Mesial	Distal
1.19	1.53	1.24	1.61	1.31	1.68	1.42	1.72	0.05	0.08	0.12	0.15	0.23	0.19
2.05	1.73	2.16	1.81	2.21	1.92	2.28	1.99	0.11	0.08	0.16	0.19	0.23	0.26
3.09	3.02	3.14	3.14	3.21	3.19	3.32	3.21	0.05	0.12	0.12	0.17	0.23	0.19
1.5	2.83	1.78	2.91	2.04	3	2.33	3.06	0.28	0.08	0.54	0.17	0.83	0.23
2.98	2.97	3.02	3.35	3.08	3.35	3.13	3.43	0.04	0.38	0.1	0.38	0.15	0.46
0.82	1.23	0.98	1.34	1	1.44	1.21	1.54	0.16	0.11	0.18	0.21	0.39	0.31
0.76	2.27	0.98	2.33	1.1	2.42	1.21	2.51	0.22	0.06	0.34	0.15	0.45	0.24
2.19	2.51	2.28	2.56	2.32	2.62	2.49	2.76	0.09	0.04	0.13	0.11	0.3	0.25
2.17	1.26	2.31	1.42	2.44	1.52	2.63	1.57	0.14	0.16	0.27	0.26	0.46	0.31
1.78	2.59	1.84	2.81	1.95	3.28	1.96	3.46	0.06	0.22	0.17	0.69	0.18	0.87

Table 2.

Crestal Bone Values and Differences at Baseline, 1^st , 3^rd & 6^th Month ( With CGF)

Implant with CGF (Group 2) ( in mm)
Baseline reading		At 1st month		At 3rd month		At 6th month		Diff btwn baseline and 1st month		Diff btwn baseline and 3rd month		Diff btwn baseline and 6th month
Mesial	Distal	Mesial	Distal	Mesial	Distal	Mesial	Distal	Mesial	Distal	Mesial	Distal	Mesial	Distal
4.19	4.72	4.21	4.82	4.32	4.84	4.46	4.86	0.02	0.1	0.13	0.12	0.27	0.14
4.34	3.72	4.42	3.81	4.51	3.94	4.62	3.96	0.08	0.09	0.17	0.22	0.28	0.24
3.46	3.24	3.52	3.34	3.61	3.52	3.84	3.56	0.06	0.1	0.15	0.28	0.38	0.32
1.26	1.57	1.31	1.68	1.34	1.71	1.38	1.73	0.05	0.11	0.08	0.14	0.12	0.26
1.95	3.45	1.98	3.54	2.19	3.67	2.5	3.69	0.03	0.09	0.24	0.22	0.55	0.24
1.5	2.04	1.62	2.15	1.74	2.29	1.84	2.34	0.12	0.11	0.24	0.25	0.34	0.3
1.4	0.66	1.52	0.76	1.62	0.98	1.73	1.06	0.12	0.1	0.22	0.32	0.33	0.4
1.1	1	1.13	1.1	1.21	1.31	1.37	1.37	0.03	0.1	0.11	0.31	0.27	0.37
1.22	2.59	1.34	2.68	1.37	3.02	1.39	3.16	0.12	0.09	0.15	0.03	0.17	0.57
3.25	2.16	3.36	2.27	3.47	2.49	3.48	2.52	0.11	0.11	0.22	0.33	0.23	0.36

Table 3.

Inter Group Comparison of Crestal Bone Values

	Groups	n	Mean	Std. Deviation	Mean difference	P
Mesial baseline to 1 mont diff	without CGF	10	0.120	0.081	0.046	0.13
	With CGF	10	0.074	0.041
Distal baseline to 1 mont diff	without CGF	10	0.133	0.101	0.033	0.32
	With CGF	10	0.100	0.008
Mesial baseline to 3 mont diff	without CGF	10	0.213	0.137	0.042	0.38
	With CGF	10	0.171	0.057
Distal baseline to 3 mont diff	without CGF	10	0.248	0.173	0.026	0.68
	With CGF	10	0.222	0.098
Mesial baseline to 6 mont diff	without CGF	10	0.345	0.202	0.051	0.50
	With CGF	10	0.294	0.119
Distal baseline to 6 mont diff	without CGF	10	0.331	0.205	0.011	0.88
	With CGF	10	0.320	0.117

*Unpaired t test

Table 4.

Comparison of Mesial & Distal Baseline To 1^st, 3^rd & 6^th Month (Group 1 &2 )

Bone density values without CGF and with CGF at 1^st, 3^rd and 6th month intervals were given [Tables 5 and 6]. The mean bone density in Group 1 at baseline, 1^st month, 3^rd month, and 6^th month was 0.60, 1.10, and 1.10 and in Group 2, it was 2.60, 5.70, and 5.7, respectively [Tables 7 and 8]. In group 1, the difference between baseline and 1^st month, baseline and 3^rd month, and baseline and 6^th month was 0.6, 1.1, and 1.1, respectively, and for group 2 it was 2.6, 5.7, and 5.7, respectively [Tables 7 and 8]. On analyzing the results statistically, there was a statistically significant difference between baseline and 1^st month, baseline and 3^rd month, and baseline and 6^th month in group 2, but in group 1, the differences were not statistically significant [Table 9].

Table 5.

Bone Density Values Without CGF ( Readings at Baseline, 1^st Month , 3^rd& 6^th Month)

without CGF
Baseline reading	At 1st month	at 3rd month	at 6th month	Diff btwn baseline and 1st month	Diff btwn baseline and 3rd month	Diff btwn baseline and 6th month
198	199	200	200	1	2	2
200	201	202	202	1	2	2
206	205	205	205	-1	-1	-1
162	162	163	163	0	1	1
161	162	163	163	1	2	2
164	165	166	166	1	2	2
160	161	160	160	1	0	0
192	193	192	192	1	0	0
182	183	184	184	1	2	2
184	184	185	185	0	1	1

Table 6.

Bone Density Values With CGF ( Readings at Baseline, 1^st Month , 3^rd & 6^th Month)

With CGF
Baseline reading	At 1st month	at 3rd month	at 6th month	Diff btwn baseline and 1st month	Diff btwn baseline and 3rd month	Diff btwn baseline and 6th month
198	201	204	204	3	6	6
196	199	202	202	3	6	6
200	202	205	205	2	5	5
161	163	166	166	2	5	5
162	165	168	168	3	6	6
160	162	165	165	2	5	5
162	165	168	168	3	6	6
192	195	198	198	3	6	6
182	185	188	188	3	6	6
183	185	189	189	2	6	6

Table 7.

Intra Group Comparison of Bone Density ( With & Without CGF)

Paired Samples Statistics
Group			n	Mean	Sth. Deviation	Mean difference	P
1.00	Pair 1	Baseline reading	10	180.90	17.94	0.6	0.02
		At 1st month	10	181.50	17.74
	Pair 2	Baseline reading	10	180.90	17.94	1.1	0.01
		At 3rd month	10	182.00	17.73
	Pair 3	Baseline reading	10	180.90	17.94	1.1	0.01
		At 6th month	10	182.00	17.73
2.00	Pair 1	Baseline reading	10	179.60	16.81	2.6	<0.001
		At 1st month	10	182.20	16.92
	Pair 2	Baseline reading	10	179.60	16.81	5.7	<0.001
		At 3rd month	10	185.30	16.94
	Pair 3	Baseline reading	10	179.60	16.81	5.7	<0.001
		At 6th month	10	185.30	16.94

Table 8.

Inter Group Comparison of Bone Density ( With & Without CGF)

Bone density - Between group comparison
	Group	n	Mean	Sth. Deviation	Mean diff	P
Diff btwn baseline and 1st month	1.00	10	0.60	0.70	2	<0.001
	2.00	10	2.60	0.52
Diff btwn baseline and 3rd month	1.00	10	1.10	1.10	4.6	<0.001
	2.00	10	5.70	0.48
Diff btwn baseline and 6th month	1.00	10	1.10	1.10	4.6	<0.001
	2.00	10	5.70	0.48

Table 9.

Comparative analysis of Bone density from Baseline to 1^st, 3^rd & 6^th month (Group 1 & 2)

DISCUSSION

The primary function of a dental implant is to act as an abutment for a prosthetic device, similar to a natural tooth root and crown.[11]

Osseointegration is defined as a direct structural and functional connection between ordered, living bone and the surface of a load-carrying implant.[12] Fugazzotto et al., demonstrated the efficacy of cylinder implant used in D4 bone. It was documented that implant success rates were much lower in D4 bone than in D1, D2, and D3.

Beginning in the 1990s, till today growth factors have emerged as the “ Holy Grail “ in wound healing.[13] Researches by Dong-seok sohn and others showed that CGFs improve bone formation and play a vital role in the osseointegration of implants. Growth factors play a major role to repair or generate tissues. Most of the growth factors are in blood plasma and platelets. Hence, platelet concentrates contain sufficient growth factors such as platelet-derived growth factors (PDGF), transforming growth factors (TGF-β), insulin-like growth factors-I, epidermal growth factors, vascular endothelial growth factors, and basic fibroblast growth factors.[14]

CGFss are known to have higher tensile strength, higher concentration of growth factors, and higher viscosity than platelet-rich fibrin (PRF), platelet-rich plasma (PRP), and hence, compressed CGF can be used as barrier membrane with growth factors as alternative collagen membrane. This barrier membrane induces the faster formation and fast tissue healing.[14]

Need for using concentrated growth factor

CGFs [Figures 5 and 6] is well-known to accelerate new bone formation. Other blood derivatives like PRP use complex protocols to prepare and chemical additives. CGFs overcome these disadvantages. CGF does not require any chemical or allergenic additives such as Bovine thrombin or anticoagulants, so is free from viral transmission diseases. CGF is 100% autologous fibrin.[7] CGF can be used alone or with a bone graft.[15] CGF with fibrin-rich blocks induces fast new bone formation.[16]

Other growth factors

Platelet rich plasma and its preparation

PRP is a rich source of growth factors [Figure 12].[17] It is an autologous source of platelet-derived growth factor and TGF-β.[18] PRP [Figure 12] enhances both hard and soft-tissue healing through concentrated platelets.[19] PRP gel is formed by mixing PRP with thrombin and calcium chloride.[20] Concentrated PRP can be prepared by further centrifugation of PRP.[21] PRP modulates cell proliferation in a cell type-specific manner.[22] The use of PRP in combination with autologous bone led to increased bone regeneration and bone density.[23] Further PRP in combination with mesenchymal stem cells enhances bone formation.[24]

Figure 12.

Platelet rich plasma

Plateler-rich fibrin

A PRF blood clot contains 4% red blood cells, 95% platelets, and 1% white blood cells [Figure 13].[25] PRF can be used along with bone grafts which promotes bone growth and maturation.[26]

Figure 13.

Platelet rich fibrin

Platelet-derived growth factor

It is considered to be the main healing hormone and has been evaluated in the large number of studies. In bone culture, PDGF stimulates mitogenic and chemotactic activities as well as protein synthesis.[27] PDGF found in other cells such as macrophages, endothelial cells, monocytes, and fibroblasts.[28]

Transforming growth factor–β

It is present at the level of the bone matrix. It promotes angiogenesis and extracellular matrix production.[29]

Mode of action of concentrated growth factor

CGF, like PRF, does not require the addition of bovine thrombin or any anticoagulants. Furthermore, altered protocols in obtaining the blood sample and in the centrifuging procedure compare with PRF. Unlike PRF however, CGF uses variable rpm from 2400 to 2700 rpm to separate cells in the venous blood, resulting in fibrin-rich blocks that are much larger, denser, and richer in growth factors than common PRF. This shows the better regenerative capacity and higher versatility when using the fibrin-rich block.[5]

Crestal bone loss around dental implants is considered to be one of the major problems and its preservation around the implant is very essential for the long-term success of implant restoration. The amount of crestal bone lost during the 1^st year after the implant placement affects the implant longevity. According to the established criteria for the assessment of implant survival and success, in the 1^st year the marginal bone level change should be <1.5 mm. Smith and Zarb concluded that alveolar bone loss should be <0.2 mm is one of the criteria for implant success.[30]

In this study, the mean crestal bone loss on the mesial aspect of implants placed with CGF (Group II) is 0.294 mm and without CGF (Group I) is 0.345 mm and the mean crestal bone loss on the distal aspect of implants placed with CGF (Group 2) is 0.320 mm and without CGF (Group 1) is 0.331 mm [Table 3]. Although the difference is within the success criteria of the implant (mean crestal bone loss <1.5 mm in 1 year), there are not many significant differences on mesial and distal aspects around implants between the two groups [Tables 3 and 4]. These results were in accordance with the pilot study done by Anshul Chugh et al., on radiological evaluation of marginal bone around dental implants.[29]

Another part of the study was done to analyze the effect of CGFs on peri-implant bone density. A total of 20 implants placed with and without CGFs and differences in the bone density values were analyzed from baseline to 1 month, 3 months, and 6 months.

Intragroup comparison of bone density values without CGF (Group 1) shows the mean difference from baseline to 1 month is 0.6, and after three and 6 months periods are 1.1 and 1.1, respectively which indicates not much significant improvement in bone density values without CGFs. On the other hand, the mean difference of the bone density values with the presence of CGFs (Group 2) from baseline to first, third, and 6^th months are found to be 2.6, 5.7, and 5.7, respectively indicates a marked increase in density values around the implants [Tables 7 and 8]. Intergroup comparison shows a significant difference between both the groups starting from as early as the 1^st month [Table 9].

The present study is in accordance with the similar studies conducted by Renu Kundu et al., with PRP on bone and implant stability revealed marked improvement in implant stability. However, the distinction is that, with CGF, the level of enhancement acquired is phenomenon and starts at the early stages of bone healing and osseointegration. Furthermore, the bone density is enhanced above the baseline level, which could mean that bone mineralization is also enhanced by CGF. A more focused study on that subject may shine light in this area.

CONCLUSION

The results of this study indicate that CGF is significantly better in the regeneration of bone around the implants when comparing with nonCGF groups. Although CGF showed improvement in bone formation, there are no many differences in crestal bone level changes on mesial and distal sides of the implants between the two groups. Alhough the present study was done with a 6 follow-up and the osseous regeneration was only measured indirectly over computer-aided software (Digora), CGF did attribute to be a much simpler and a better platelet concentrate, in promoting osseous regeneration. CGF also aided in increasing the density of the bone around the implant from baseline to a much higher level. This attribute could be used in cases where bone mineralization is compromised. However, the exact action of CGF on bone mineralization needs to be studied further.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.