UNIVERSIDADE ESTADUAL PAULISTA

“JÚLIO DE MESQUITA FILHO”

Instituto de Ciência e Tecnologia

Campus de São José dos Campos

ORIGINAL ARTICLE DOI: https://doi.org/10.4322/bds.2023.e3987

Braz Dent Sci 2023 Oct/Dec;26 (4): e3987

Bone density and implant stability with advanced platelet-rich

ﬁbrin in immediately loaded- implant assisted mandibular

overdentures

Densidade óssea e estabilidade dos implantes com ﬁbrina rica em plaquetas avançada em overdentures mandibulares com

carga imediata

Eman Sabry Ata ALLAH1 , Fadel Elsaid ABD ELFATAH2 , Hoda Mohamed Amin RASHED2 , Mona Talaat Mohamed HASSIB3 

1 - Kafr El-shiekh University, Faculty of Dentistry. Kafr El-shiekh, Egypt.

2 - Tanta University. Faculty of Dentistry. Tanta, Egypt.

3 - Kafr El-shiekh University, Faculty of Medicine, Diagnostic Radiology. Kafr El-shiekh, Egypt.

How to cite: Allah ESA, Abd Elfatah FE, Rashed HMA, Hassib MTM. Bone density and implant stability with advanced platelet-rich brin in

immediately loaded- implant assisted mandibular overdentures. Braz Dent Sci. 2023;26(4):e3987. https://doi.org/10.4322/bds.2023.e3987

ABSTRACT

Objective: The aim of this study is to determine the effect of Advanced Platelet-Rich Fibrin on bone density

and implant stability in immediately loaded- implant-assisted mandibular overdentures (Split-mouth study).

Material and Methods: Ten completely edentulous patients received two implants in the mandibular canine

region and locator attachments were used to retain immediately loaded- implant mandibular overdentures.

Each patient served in two Groups, one Group for each side. One side of the mandible received an implant with

topical application of Advanced Platelet-Rich Fibrin in the implant osteotomy site (Group I) and the other site

received an implant without application of Advanced platelet-rich brin (Group II). Each patient was examined

clinically for implant stability using Osstell Mentor device and radiographically by ultra-low dose CT scan to

measure bone density around the implant at baseline, three, six months, and one year. Results: There were

no statistically signicant differences (P>.05) in bone density and implant stability among the studied Groups

during one year follow-up period. Conclusion: Advanced Platelet-Rich Fibrin has no effect on bone density and

implant stability in immediately loaded implant-assisted mandibular overdenture.

KEYWORDS

Advanced platelet-rich brin; Bone density; Immediately loaded implant; Implant stability; Locator attachment;

Mandibular overdentures.

RESUMO

Objetivo: O objetivo deste estudo é determinar o efeito da Fibrina Rica em Plaquetas Avançada na densidade

óssea e estabilidade dos implantes em Overdentures mandibulares com carga imediata (estudo de boca dividida).

Material e Métodos: Dez pacientes edêntulos foram submetidos à instalação de dois implantes mandibulares na

região dos caninos e pilares locator foram utilizados como sistema de retenção para as overdentures mandibulares

com carga imediata. Cada paciente participou nos dois grupos, sendo um grupo para cada lado. Um lado da

mandíbula recebeu implante com aplicação tópica de Fibrina Rica em Plaquetas Avançada no local do sítio

cirúrgico do implante (Grupo I) e o outro local recebeu implante sem aplicação de Fibrina Rica em Plaquetas

Avançada (Grupo II). Cada paciente foi examinado clinicamente quanto à estabilidade do implante usando o

dispositivo Osstell Mentor e radiogracamente por tomograa computadorizada de ultrabaixa dose para medir

a densidade óssea ao redor do implante no início do estudo, três, seis meses e um ano. Resultados: Não houve

diferenças estatisticamente signicativas (P>0,05) na densidade óssea e na estabilidade do implante entre os

Braz Dent Sci 2023 Oct/Dec;26 (4): e3987

Allah ESA et al.

Bone density and implant stability with advanced platelet-rich fibrin in immediately loaded- implant assisted mandibular overdentures

Allah ESA et al. Bone density and implant stability with advanced platelet-rich

ﬁbrin in immediately loaded- implant assisted mandibular

overdentures

INTRODUCTION

Mandibular dentures pose challenges

related to poor stability and retention [1]. Dental

implants have greatly improved outcomes of

treatment in an edentulous patient. In many

developed countries, the two--implant for

the mandibular overdenture is considered a

minimum standard of care [2]. Mandibular

implant over denture has many benets such as;

improving stability, retention, chewing ability,

speaking, and decreasing the resorption of the

residual ridge [3].

Various loading protocols for dental implants

have been studied. Immediate loading protocol

may reduce some patient burdens such as

multiple visits, costs, waiting for the final

restoration, inconvenience, and morbidity

related to multiple surgical phases [4,5]. Many

attachments were used according to inter-arch

space. Locator attachments were indicated in

cases of limited inter-arch space and provided an

adequate means of retention in such cases [6].

Besides, the common challenges of immediate

loading, the repeated removal of overdenture

may be detrimental to early osseointegration.

The healing phase after implant installation is a

critical phase for immediate loading protocol so

it must be carefully monitored [7].

The Osseointegration of dental implants

is defined as the apparent direct attachment

or the connection of osseous tissue to an inert,

alloplastic material without intervening brous

connective tissue [8]. The biological fixation

of the implant is an early formation of peri-

implant bone trabeculae, which conrms tissue

anchorage. Biological xation is different from

primary stability. Implant primary stability is a

mechanical xation, which is obtained during the

insertion of the implant. Secondary stability is

biological stability obtained by bone regeneration

and remodeling [9].

There are several procedures to improve

osseointegration such as the application of

Bone morphogenetic proteins, Melatonin, and

Advanced-Platelet-Rich Fibrin (A-PRF). Bone

morphogenetic proteins are the growth factors

that are naturally found within the bone matrix

and they play a role in the regulation of bone

volume and bone regeneration. The applications

of recombinant human bone morphogenetic

proteins onto the implant surface before threading

the implant into the osteotomy site may improve

osseointegration and implant stability [10].

Melatonin hormone stimulates the synthesis

of type I collagen bers and acts on osteoclasts to

reduce the resorption of the osseous matrix. Local

administration of melatonin in the osteotomy

site increases bone density and improves the

osseointegration processes around immediate-

loaded implant supported overdentures [11].

A-PRF is the last generation of platelet

concentrates. Platelet concentrates are autologous

biological products generated from the blood of

patients and are rich in platelets and growth factors

(GFs). Soft and hard tissue regeneration can be

improved by using platelet concentrates alone or

as an adjunctive treatment in dentoalveolar and

maxillofacial surgeries [12,13].

Bone density can be measured by Hounseld

Unit (HU), which is the calibrated grey value. HU is

relatively consistent across different Multi-Detector

Computed Tomography (MDCT) scanners, unlike

CBCT. In addition, the calibration of HU is an

integrated part of quality control in MDCT. Ultra-

low dose- CT examination of the jaws may decrease

the effective dose to be equal to the full mouth

examination utilizing intra-oral lms [14,15].

Resonance frequency analysis (RFA) is

a noninvasive-diagnostic system, which can

measure implant stability through structural

and vibration principle analysis. RFA is simpler,

more objective, and more reliable than the

other noninvasive-diagnostic systems. Based on

RFA, Implant stability quotient (ISQ) values are

displayed on Osstell apparatus for measuring

implant stability [16,17].

grupos estudados durante o período de acompanhamento de um ano. Conclusão: A Fibrina Rica em Plaquetas

Avançada não tem efeito na densidade óssea e na estabilidade de implantes em Overdentures mandibulares

com carga imediata.

PALAVRAS-CHAVE

Densidade óssea; Estabilidade do implante; Fibrina rica em plaquetas avançada; Implante com carga imediata;

Overdentures mandibulares; Pilar locator.

Braz Dent Sci 2023 Oct/Dec;26 (4): e3987

Allah ESA et al.

Bone density and implant stability with advanced platelet-rich fibrin in immediately loaded- implant assisted mandibular overdentures

Allah ESA et al. Bone density and implant stability with advanced platelet-rich

ﬁbrin in immediately loaded- implant assisted mandibular

overdentures

This study aimed to determine the effect of

Advanced-Platelet-Rich Fibrin on bone density and

implant stability in immediately loaded implant-

assisted mandibular overdentures clinically and

radiographically using Osstell and ultra-dose

CTscan at baseline, three, six months, and one year.

The null hypothesis of this study was that there

was no effect of Advanced Platelet-Rich Fibrin on

bone density and implant stability in immediately

loaded -implant-assisted mandibular overdenture.

MATERIALS AND METHODS

Ethical considerations

The purposes of the study, the nature of

implant surgery, possible risks, complications, the

photography of the procedure, and the frequency

of exposure to radiation were explained to

the patients. Informed consent was obtained

according to guidelines on human research

adopted by the Research Ethics Committee,

Faculty of Dentistry, Tanta University which

approved the performance of this study after

fulfilling the necessary requirements of the

committee with code # RP-2-20-3.

Sample size calculation

The total sample size in this study is ten patients

based on the data taken from a previous study

which eevaluatedclinically and radiographically

the effect of leukocyte platelets-rich brin (L-PRF)

on the stability and crestal bone resorption of early

loaded implants [18]. The signicance level was

0.05, the power sample size was more than 0%

for this study and the condence interval was 95%

and the actual power was 96.08%. The sample

size was calculated using a computer program G

power version 3.

The formula for sample size was:

( )

Z P 1P

Sample Size ×× −

(1)

where: Z = Z value (1.96 for 95% condence

level); p = percentage picking a choice, expressed

as decimal; c = condence interval, expressed

as decimal.

Patient selection

Ten completely edentulous patients

(age Group 50-65 years) were selected from

the outpatient clinic of the Department of

Prosthodontics, Faculty of Dentistry, Tanta

University, to participate in this study. Inclusion

criteria were that the patients were free of any

systemic diseases that affect bone and soft tissue

healing, and had normal maxilla-mandibular

relationships with limited inter-arch space

where locator attachments were indicated.

The mandibular intercanine region had sufcient

bone to be appropriate for the planned implants.

The patients had the psychological and physical

ability to tolerate implant surgery. Exclusion

criteria were a history of chemotherapy or

radiotherapy, para-functional occlusal habit,

bad oral hygiene, and heavy smoking. These

factors have adverse effects on osseointegration

and this study aims to clarify the effect of A-PRF

on bone density and implant stability without

risk factors. The selected criteria were reported.

Five patients with these selected criteria came to

the Department of Prosthodontics every month.

Opaque-sealed envelopes were used for simple

randomization of the subjects.

Study design

This study was a split-mouth study; for each

patient, two dental implants were inserted in the

mandibular inter-foraminal area at the canine

region. Each patient served into two Groups, one

Group for each side. One side of the mandible

received an implant with topical application of

A-PRF in the implant osteotomy site (Group I)

and the other site received an implant without

application of A-PRF (Group II). The trial was

triple-blinded as patients did not know which side

A-PRF inserted into also observer/radiologist and

statistician were blinded.

Surgical and prosthetic procedure

Conventional complete denture was

constructed and was delivered for each patient.

Duplication of the lower denture was made for

the construction of a radiographic stent. Pre-

operative CBCT with radiographic stent was

obtained for each patient to evaluate the ridge

width, height, bone quality, and quantity at

canine regions of mandible [19].

The radiographic stent was modified for

use as a surgical guide for freehand drilling by

removing the lingual flange and leaving the

labial ange in the anterior region. Before the

Braz Dent Sci 2023 Oct/Dec;26 (4): e3987

Allah ESA et al.

Bone density and implant stability with advanced platelet-rich fibrin in immediately loaded- implant assisted mandibular overdentures

Allah ESA et al. Bone density and implant stability with advanced platelet-rich

ﬁbrin in immediately loaded- implant assisted mandibular

overdentures

operation, it was kept in 2% glutaraldehyde for

24 hours [20].

Pre-operative medications were prescribed

for all patients. Augmentin1g cap (Augmentin

cap, GlaxoSmithKline, England) was prescribed

every 12 hours before the operation and one

week after surgery. Patients were motivated to

maintain good oral hygiene and instructed to

use 0.12% Chlorohexidine mouthwash before

surgery.

The non-limiting surgical guide was inserted

to identify the implant site and was then removed.

Bard-barker blade no.15 was used to make

crestal incisions one cm mesial and distal to the

planned implant site. A mucoperiosteal elevator

was used to reect the ap. A bone le was used

to atten the crestal bone and smooth any sharp

bone edges.

For each patient, two dental implants

(Superline, Dentium Medical Devices Tec.

Company, Korea) were inserted in the mandibular

canine region. The implants were 3.6 mm in

diameter and 12 mm in length.

The protocol [20] for implant osteotomy

site preparation:

1- The pilot drill (diameter 2.2 mm) was used

to initiate the drilling in vertical direction

with moving-up and down. A reduction

handpiece and electric motor at speed of

2000 rpm (for D1 and D2) were used with

copious amounts of chilled saline external

irrigation until reached the length of 9 mm

at both osteotomy sites;

2- The paralleling pins were used to detect the

parallelism and alignment of the osteotomy

sites. Drilling was completed until reached

12 mm depth;

3- The second drill (diameter 2.6 mm) and

nal shaping drill (diameter 2.85 mm for

3.6 mm xture) were used for widening the

osteotomy. The Countersink of diameter 3.6

was used in highly dense bone D1 and D2

mm for 3.6 mm xture at about 8 mm length.

Meanwhile, the osteotomy site was prepared;

Advanced PRF (A-PRF) was prepared by centrifuge

a plain glass tube lled with 10 ml blood from

patients’ brachial veins through laboratory mini-

centrifuge (Centrifuge model no.800D, Delta Lab

Company, China) for 14 minutes with a speed of

1500 rpm. Another glass tube of 10 mL of saline

was used in the centrifuge in order to act as a

counterbalance [21].

After centrifugation, A-PRF gel was at

the top and erythrocytes were at the bottom.

(Figure 1a) A-PRF membrane was obtained and

was cut into small sections using sterile scissors.

The membrane of A-PRF was laid on the orice of

the osteotomy site and was squeezed into the site

by threading the implant into the site (Group I)

(Figure 1b) However, the implants were installed

directly in the osteotomy sites at the right side

(Group II). The implants were installed into the

osteotomy sites by screwdriver and then by hand

ratchet until the implant platform became ushed

with the bone (Figure 2).

Prior to immediate loading, implant pri-

mary stability was assessed by Osstell Mentor

device (Osstell Mentor, Gothenburg, Sweden)

(Figure 3). Primary stability is a signicant fac-

tor for success of the dental implant and crucial

with immediately loaded implants. The goal

Figure 1 - (a) Preparation of A-PRF; (b) Membrane of A-PRF was laid

on the oriﬁce of the osteotomy site and was squeezed into the site

by threading implant into the site.

Braz Dent Sci 2023 Oct/Dec;26 (4): e3987

Allah ESA et al.

Bone density and implant stability with advanced platelet-rich fibrin in immediately loaded- implant assisted mandibular overdentures

Allah ESA et al. Bone density and implant stability with advanced platelet-rich

ﬁbrin in immediately loaded- implant assisted mandibular

overdentures

of primary stability is keeping micromovement

within accepted levels between 50 and 150 μm.

Primary (mechanical) stability leads to reaching

secondary (biological) stability. ISQ values above

65 are considered acceptable for immediate load-

ing if were not reached shifting to delayed loading

were preferred [22,23].

Locator abutments (Positioner abutment,

Dentium Medical Devices Tec. Company, Korea)

were mounted into the implants. each ap was

repositioned and primary closured was carried

by using interrupted 4\0 silk suture (Figure 4).

After surgery, Augmentin 1g every 12 hours

and Ibuprofen 400mg every 8 hours were

prescribed for one week. During the rst 24 hours,

patients were instructed to apply cold packs extra

orally at the operative site. On the second day,

they were instructed to use Chlorhexidine 0.12%

mouthwash every 8 hours and rinse with warm

saline until the rst postoperative week ended.

Patients were instructed to eat a soft diet and

avoid hard food during the healing period. After

one week, the sutures were removed.

Within two weeks post-operatively, the

pick-up procedure for the immediate loading

mandibular overdenture (Figure 5) was

completed as follow: a white block-out spacer

was adapted over the corresponding locator

abutment. The Locator metal housing with

processing insert was positioned over the locator

abutment and was marked. The undersurface of

the mandibular denture at the abutment sites

was sufciently relieved. Two small holes were

made in the lingual surface of the denture to

permit the escape of excess acrylic resin material

through the pick-up procedure. The denture was

tried to ensure complete seating. Locator metal

housing was picked up to the undersurface of

the lower denture using self-cure acrylic resin,

while the patient occluded in centric relation.

The block-out spacer was removed. Male nylon

inserts replaced the processing inserts. These

inserts were provided in different colors ivory,

orange, and blue with extra light retention, light

retention and medium retention, respectively.

The ivory insert was used rst then replaced by an

orange insert and a blue insert when the retention

reduced. The occlusion was checked for any

occlusal premature contacts and the overdenture

was polished. Patients were instructed to follow

strict oral hygiene measures. The patients were

recalled every 3 days in the first 3 weeks for

denture adjustment and occlusal renement.

Implant stability

Implant stability was measured by Osstell

Mentor device during the follow-up period. Locator

attachment (Positioner abutment, Dentium Medical

Figure 2 - Diagram showing the application of advanced PRF into the implant site.

A-PRF: Advanced PRF.

Figure 3 - Measuring implant primary stability by Osstell Mentor

device.

Braz Dent Sci 2023 Oct/Dec;26 (4): e3987

Allah ESA et al.

Bone density and implant stability with advanced platelet-rich fibrin in immediately loaded- implant assisted mandibular overdentures

Allah ESA et al. Bone density and implant stability with advanced platelet-rich

ﬁbrin in immediately loaded- implant assisted mandibular

overdentures

Devices Tec. Company, Korea) was unscrewed by

a screwdriver. The smart peg was attached to the

implant by nger-tight and stimulated magnetically

by a measuring probe. The ISQ values were

recorded and the mean values of two perpendicular

measurements were obtained. The smart peg was

removed then the locator attachment was screwed.

Measurements were recorded on the day of surgery,

3, 6 months and 1 year for each implant [24].

Radiographic assessment

Radiographic examinations were carried out

by CT scanner (Aquilion One, 320 Multi -Detector,

Toshiba Medical Systems, Japan) using ultralow

dose protocol on the day of surgery, 3, 6 months,

and 1 year. Scan parameters were tube voltage of

80 kV, tube current of 50 mAs, pitch of 0.5mm,

and Field of view was about (7.5cmx10cm).

CT dose index volume was approximately

2.50 mGy [15].

Model Based Iterative Reconstruction

(MBIR) with a standard kernel was used to

reconstruct images. Using MBIR produces

images with less noise allowing even further

dose reductions than the traditionally used

filtered back projection. Peri implant bone

density was measured by Houseeld units (HU).

Measurements were performed at 0.5 mm away

from each surface of each implant to diminish

the scattered radiation effect. The bone densities

were measured on the sagittal and coronal views

(Figure 6). The mean values of readings were

used for statistical analysis.

Statistical analysis

Data from the study were collected, tabulated

and statistically analyzed. Data were fed to the

computer and analyzed using IBM-SPSS software

package version 20.0. (Armonk, NY: IBM Corp).

Quantitative data were described using range,

mean and standard deviation. Signicance of

the obtained results was judged at the 5% level.

The used tests were: ANOVA with repeated

measures for normally distributed quantitative

variables, to compare between more than two

periods, and Post Hoc test (Bonferroni adjusted)

for pairwise comparisons. Student t-test was

Figure 4 - Locator abutments were mounted into the implants.

Figure 5 - (a) Locator metal housing with white block-out spacer in

place; (b) Locator metal housing was picked up.

Braz Dent Sci 2023 Oct/Dec;26 (4): e3987

Allah ESA et al.

Bone density and implant stability with advanced platelet-rich fibrin in immediately loaded- implant assisted mandibular overdentures

Allah ESA et al. Bone density and implant stability with advanced platelet-rich

ﬁbrin in immediately loaded- implant assisted mandibular

overdentures

used to compare between two studied Groups.

P < 0.05 was considered to be statistically

signicant.

RESULTS

The results showed that implant stability

changed over time in both Groups. There was

a statistically significant difference between

baseline, 3, 6 months and 1 Year where

P<0.001 for both Groups. The mean and

standard deviation values of implant stability

decreased at three months of follow-up period

and then increased at six months and 1 year in

both Groups (Table I).

Using the student t-test to compare between

two Groups regarding implant stability revealed

that there was no statistically signicant difference

between Group I and Group II at all follow-up

periods. At baseline p0= 0.584, at three months

p0=0.677, at six months p0=0.600, at 1 year

p0=0.496 (Table I).

The results showed that peri-implant bone

density changed over time in both Groups.

The mean and standard deviation values of

peri-implant bone density in both Groups

decreased at three months of follow-up period

and then increased at six months and 1 year.

There was a statistically signicant difference

Table I - Comparison between the two studied Groups concerning implant stability throughout the evaluation periods

Implant stability

Group I Group II p-value

(t)

Mean ± SD. Mean ± SD.

Baseline 75.90 ± 4.53 74.80 ± 4.29 0.584 (0.557)

3 months 70.50 ± 3.41 69.80 ± 3.97 0.677 (0.423)

6 months 73.30 ± 3.47 72.40 ± 4.06 0.600 (0.533)

1 year 76.40 ± 3.86 75.20 ± 3.85 0.496 (0.695)

p1-value (F) <0.001* (48.916*) <0.001* (49.713*)

Baseline – 3 months <0.001* <0.001*

Baseline – 6 month 0.002* 0.041*

Baseline – 1 year 1.000 1.000

3 months –6 month 0.002* <0.001*,

3 months – 1 year <0.001* <0.001*,

6 months – 1 year <0.001* <0.001*

t: Student t-test; F: F test (ANOVA) with repeated measures, Signiﬁcant between periods was done using Post Hoc Test (adjusted Bonferroni);

P: p value for comparing between both Groups in each period; p1: p value for comparing between the studied periods. *Statistically signiﬁcant

at p ≤ 0.05.

Figure 6 - Measuring peri-implant bone density.

Braz Dent Sci 2023 Oct/Dec;26 (4): e3987

Allah ESA et al.

Bone density and implant stability with advanced platelet-rich fibrin in immediately loaded- implant assisted mandibular overdentures

Allah ESA et al. Bone density and implant stability with advanced platelet-rich

ﬁbrin in immediately loaded- implant assisted mandibular

overdentures

between baseline, 3, 6 months and 1 Year where

P<0.001 for both Groups (Table II).

Using the student t-test to compare between

two Groups regarding peri-implant bone density

revealed that there was no statistically signicant

difference between Group I and Group II at all

follow-up period. At baseline p0=0.947, at three

months p0 =0.911, at six months p0=0.908, at

1 year p=0.818 (Table II).

DISCUSSIONS

This study was a split-mouth design because

it permits reducing variability and bias through

self-controls increasing the statistical efciency.

It allows the greatest opportunity for comparability

and reduces the sample size [25]. However, it was

found that due to the mechanical connection of

the two implants of different intervention Groups

by superstructures, loads on one implant would

be transferred to the other; which may result in

carry-across effects. Carry-across effects on results

cannot be tested or assessed [26].

Two implants have been considered as

the minimum request for mandibular implant

overdenture treatment with a high success rate

and a cost-effective treatment for edentulous

individuals [27]. Immediate loading protocol

was followed in this study because it improves

the quality of life and patient satisfaction by

decreasing the rehabilitation time [28,29].

However regarding two-implant mandibular

overdenture with various loading protocols and

locator attachments, the implant survival rates

for locator with immediate loading were less than

that with delayed loading [30].

Advanced Platelet-Rich Fibrin was applied in

this study because it is an autologous bioactive

material that can accelerate soft and bone tissue

healing in implant surgery. Components of A-PRF

are fibrin, Leukocytes, and platelets. Growth

factors are released from activated platelets in

A-PRF and promote cell proliferation, collagen

synthesis, and osteoid production. Enhanced

implant osseointegration could make early and

immediate loading more predictable [31,32].

For this study, implant stability was

measured in ISQ value by the Osstell apparatus.

Osstell ISQ measurements are quantitative,

highly reliable, and reproducible measurements

for implant stability so were used to assess the

osseointegration, immediate load possibility, and

follow-up [33]. ISQ values in this study were

above 65 at the insertion of implants (implant

primary stability), which supports the use of

immediate loading [34].

CBCT has many applications for different

aspects of implantology either pre-surgical or post-

surgical such as assessing anatomical structures,

bone volume, shape, quality, static surgical guide

fabrication, dynamic guided surgery, the evaluation

of graft healing, and assessing complications related

to neurovascular trauma [35,36].

This study focused on monitoring the

changes in bone density and their relation to

immediate loading after the application of A-PRF

in osteotomy sites. Understanding these changes

Table II - Comparison between the two studied Groups concerning peri- implant bone density throughout the evaluation periods

Bone density

Group I Group II

p-value(t)

Mean ± SD. Mean ± SD.

Baseline 1297.9 ± 108.6 1301.3 ± 115.4 0.947 (0.068)

3 months 1253.1 ± 112.3 1258.8 ± 111.9 0.911 (0.114)

6 months 1289.7 ± 99.38 1294.9 ± 100.0 0.908 (0.117)

1 year 1320.1 ± 97.95 1330.5 ± 101.1 0.818 (0.234)

p1-value(F) <0.001* (37.999*) <0.001*(41.753*)

Baseline – 3 months <0.001* <0.001*

Baseline – 6 month 1.000 1.000

Baseline – 1 year 0.016* 0.036*

3months –6 month 0.002* 0.001*

3 months – 1 year <0.001* <0.001*

6 months – 1 year 0.001* <0.001*

t: Student t-test; F: F test (ANOVA) with repeated measures, Signiﬁcant between periods was done using Post Hoc Test (adjusted Bonferroni);

P: p value for comparing between both Groups in each period; p1: p value for comparing between the studied periods. *Statistically signiﬁcant

at p ≤ 0.05.

Braz Dent Sci 2023 Oct/Dec;26 (4): e3987

Allah ESA et al.

Bone density and implant stability with advanced platelet-rich fibrin in immediately loaded- implant assisted mandibular overdentures

Allah ESA et al. Bone density and implant stability with advanced platelet-rich

ﬁbrin in immediately loaded- implant assisted mandibular

overdentures

is necessary to achieve improvements in implant

survival rate [37].

This study did not depend on CBCT for

the evaluation of bone density throughout

follow-up periods for many reasons such as;

the lack of standardized grey value, limitations

of reconstruction algorithms currently applied,

and asymmetrical patient position. In addition,

CBCT lack Hounseld scoring (standardized grey

level calibration). Hounsfield units have been

designed for medical CT but are not applicable

for CBCT. Compared with Hounseld units for

medical CT, grey values for CBCT device has been

found to be unreliable and only can be used as a

qualitative method to determine the change of

the bone around dental implants with signicant

variations [38].

The radiographic images in this study during

follow-up were derived from ultra-low-dose Multi-

Slice Computed Tomography scans, because

Multi-Slice Computed Tomography (MSCT) is

the gold standard for measuring bone density

based on Hounseld values. In addition, the mean

absorbed dose using an ultra-low dose- MSCT of

2.5 mGy is equivalent to a full mouth survey with

intra-oral lms [39]. Density estimation errors

due to differences in angulation of scanning by

MSCT are less than CBCT. Misalignment during

scanning is affected by different types of sources.

MSCT scan uses a fan beam source, but CBCT

uses a cone beam source [40].

A statistically significant decrease was

recorded in implant stability from baseline to

3 months for both Groups. Implant stability

quotient (ISQ) values were to some extent low,

but within the acceptable range. The explanation

for that decreasing may be related to the

transformation from primary stability to secondary

stability in this phase; initial bone remodeling

is characterized by increasing osteoclastic

activity that led to decrease the bone-implant

anchorage [41]. In addition, the immediate

loading of non-splinted implants might increase

micro-movements and marginal bone loss

affecting implant stability. These results were

in agreement with other studies of immediate

loading for lower overdentures [42,43].

When comparing the two groups, there was

no statistically signicant difference between both

Groups at each follow-up period. These results

were in agreement with another study, which

reported the long-term effect of PRF on implant

stability [44].This can be related to A-PRF which

has an effect on osseous regeneration during

the early stage of the healing process. A- PRF

released the greatest amount of platelet-derived

growth factor AB and transforming growth

factor beta 1 on days 7 and 14, respectively.

On 14 days, A- PRF demonstrated the highest

alkaline phosphatase activity and A- PRF

treated osseous cells demonstrated the peak of

mineralization [45,46].

The results of this study were in disagreement

with other studies, which reported that PRF may

improve implant stability and the PRF Group had

higher ISQ values in comparison to non-coated

implants. This improvement can be explained

as they tracked the effect of PRF on the implant

stability during the early phase of osseointegration

at 1, 4, and 6 weeks with a lack of long-term

follow-up [47,48]. Kalash S et al. [49] reported

that A-PRF may cause improvement in implant

stability at 3 months and 6 months of follow-up.

This can be attributed to the use of xenograft in

combination with A-PRF around dental implants

in their study.

On comparison between both Groups at

all follow-up periods, no statistically signicant

difference regarding bone density was reported.

These results were in harmony with the study of

Alhaj et al. [50] who examined the efciency of

using an advanced platelet-rich brin–autogenous

bone graft mixture around immediately placed

dental implants in the mandibular molar

region. They reported no difference regarding

bone density when using this mixture around

immediately placed implants. The explanation

may be that the growth factors are released

rapidly leading to the short-term effect of PRF

on osseointegration [25]. In addition, the dense

clotting of platelets and brin on titanium surface

was 1000 times weaker with platelet concentrates

than with whole blood [51].

On the other hand, El Shafei et al. [52]

investigated the effect of using PRF alone and PRF

loaded with simvastatin (a pharmacological drug)

on bone changes around implant. They reported

that PRF loaded with simvastatin enhances bone

healing, particularly in patients with compromised

bone quantity or quality. Another experimental

study by To et al. [53] investigated A-PRF clots

in sockets of beagle dogs after tooth extraction

examined osteopontin and osteocalcin activities

during bone formation in the socket by using

Braz Dent Sci 2023 Oct/Dec;26 (4): e3987

Allah ESA et al.

Bone density and implant stability with advanced platelet-rich fibrin in immediately loaded- implant assisted mandibular overdentures

Allah ESA et al. Bone density and implant stability with advanced platelet-rich

ﬁbrin in immediately loaded- implant assisted mandibular

overdentures

immunouorescence staining, and evaluated the

bone formation ratio by histological analysis.

The study results showed that the application

of A-PRF may enhance and accelerate new bone

formation by increasing osteoblastic activity.

Tracking the effect of A-PRF during the early

phase of osseointegration (short-term follow-up)

and small sample size are limitations of our study.

Further studies using different forms of platelet-

rich brin could be recommended.

CONCLUSIONS

Advanced Platelet-Rich Fibrin has no

effect on implant stability and bone density in

immediately loaded- implant-assisted mandibular

overdenture. Application of Advanced Platelet-

Rich in implant osteotomy site does not improve

the implant stability in immediately loaded-

implant assisted mandibular overdenture cases.

Author’s Contributions

ESAA: Conceptualization, Resources, Data

Curation, Methodology, Writing – Original

Draft Preparation. FEAE: Conceptualization,

Supervision, Methodology, Writing – Review &

Editing. HMAR: Conceptualization, Methodology,

Supervision, Writing – Review & Editing. MTMH:

Conceptualization, Methodology, Supervision,

Writing – Review & Editing.

Conict of Interest

None.

Funding

None.

Regulatory Statement

This study was conducted in accordance with

all the provisions of the local human subject’s

oversight committee’s guidelines and policies of

the ethical committee; Faculty of Dentistry, Tanta

University. The approval code # RP-2-20-3

REFERENCES

1. Cooper LF. The current and future treatment of edentulism.

J Prosthodont. 2009;18(2):116-22. http://dx.doi.org/10.1111/

j.1532-849X.2009.00441.x. PMid:19254301.

2. Feine JS, Carlsson GE, Awad MA, Chehade A, Duncan WJ,

Gizani S,etal. The McGill consensus statement on overdentures.

Mandibular two-implant overdentures as ﬁrst choice standard

of care for edentulous patients. Gerodontology. 2002;19(1):3-4.

PMid:12164236.

3. Kutkut A, Bertoli E, Frazer R, Pinto-Sinai G, Fuentealba Hidalgo R,

Studts J. A systematic review of studies comparing conventional

complete denture and implant retained overdenture. J

Prosthodont Res. 2018;62(1):1-9. http://dx.doi.org/10.1016/j.

jpor.2017.06.004. PMid:28666845.

4. Emami E, Cerutti-Kopplin D, Menassa M, Audy N, Kodama N,

Durand R, et al. Does immediate loading affect clinical and

patient-centered outcomes of mandibular 2-unsplinted-implant

overdenture? A 2-year within-case analysis. J Dent. 2016;50:30-6.

http://dx.doi.org/10.1016/j.jdent.2016.04.009. PMid:27112723.

5. Abdelfattah F, Elsegai A, Yousef A, Mohyeldin A. Evaluation of

two different occlusal concepts used in immediately loaded

mandibular implant overdenture. Egypt Dent J. 2008;54:1435-47.

6. Miler AMQP, Correia ARM, Rocha JMC, Campos JCR, da Silva

MHGF. Locator® attachment system for implant overdentures:

a systematic review. Stomatologija. 2017;19(4):124-9.

PMid:29806650.

7. Cao ZL, Li X, Lin LJ, Chen YH. Immediate or delayed loading

protocols for two-implant mandibular overdentures: a systematic

review and meta-analysis of randomized controlled trials. J

Prosthet Dent. 2021;126(6):742-8. http://dx.doi.org/10.1016/j.

prosdent.2020.09.011. PMid:33139056.

8. Academy of Prosthodontics. The Academy of Prosthodontics

Foundation. The Glossary of Prosthodontic Terms: ninth Edition. J

Prosthet Dent. 2017;117(5S):e1-105. http://dx.doi.org/10.1016/j.

prosdent.2016.12.001. PMid:28418832.

9. Guglielmotti MB, Olmedo DG, Cabrini RL. Research on implants

and osseointegration. Periodontol 2000. 2019;79(1):178-89.

http://dx.doi.org/10.1111/prd.12254. PMid:30892769.

10. Ragheb NA, Rekaby A, Farahat A. Bone morphogenetic protein

effect on implant stability and bone height in immediately

loaded implant supported mandibular overdenture (randomized

clinical trial). Int Dent Med J Adv Res. 2017;3(1):1-7. http://dx.doi.

org/10.15713/ins.idmjar.60.

11. Rostom DA, Ela AA, Abdalla MF. Eff ect of melatonin on

osseointegration of immediate loading implant supported

mandibular over denture: randomized clinical trail. Int Dent Med J

Adv Res. 2016;2(1):1-5. http://dx.doi.org/10.15713/ins.idmjar.55.

12. Augustina EF, Rivai NR, Gifary HM. The expression of matrix

metalloproteinase-13 (MMP-13) on xenograft and PRF in bone

regeneration. Braz Dent Sci. 2023;26(2):e3366. http://dx.doi.

org/10.4322/bds.2023.e3366.

13. Prakash S, Thakur A. Platelet concentrates: past, present and

future. J Maxillofac Oral Surg. 2011;10(1):45-9. http://dx.doi.

org/10.1007/s12663-011-0182-4. PMid:22379320.

14. Widmann G, Bischel A, Stratis A, Kakar A, Bosmans H, Jacobs

R,etal. Ultralow dose dentomaxillofacial CT imaging and iterative

reconstruction techniques: variability of Hounsfield units and

contrastto-noise ratio. Br J Radiol. 2016;89(1060):20151055.

http://dx.doi.org/10.1259/bjr.20151055. PMid:26859336.

15. Widmann G, Al-Shawaf R, Schullian P, Al-Sadhan R, Hörmann R,

Al-Ekrish AA. Effect of ultra-low doses, ASIR and MBIR on density

and noise levels of MDCT images of dental implant sites. Eur

Radiol. 2017;27(5):2225-34. http://dx.doi.org/10.1007/s00330-

016-4588-8. PMid:27655306.

16. Zanetti EM, Pascoletti G, Calì M, Bignardi C, Franceschini G.

Clinical assessment of dental implant stability during follow-up:

what is actually measured, and perspectives. Biosensors

(Basel). 2018;8(3):68. http://dx.doi.org/10.3390/bios8030068.

PMid:30011870.

Braz Dent Sci 2023 Oct/Dec;26 (4): e3987

Allah ESA et al.

Bone density and implant stability with advanced platelet-rich fibrin in immediately loaded- implant assisted mandibular overdentures

Allah ESA et al. Bone density and implant stability with advanced platelet-rich

ﬁbrin in immediately loaded- implant assisted mandibular

overdentures

17. Gupta RK, Padmanabhan TV. An evaluation of the resonance

frequency analysis device: examiner reliability and repeatability

of readings. J Oral Implantol. 2013;39(6):704-7. http://dx.doi.

org/10.1563/AAID-JOI-D-11-00099. PMid:21970725.

18. Ragab OM, El Nahass H, Shoeib M. Effect of L-PRF on stability

of early loaded immediate implants. Cairo Dent J. 2013;29:1-8.

19. Borg H, Amin H, Elshiekh M. Comparative study of inter-implant

distance measurements (Cone beam versus clinical methods).

Egypt Dent J. 2017;63:487-91.

20. Moy PK, Beumer J 3rd, Pozzi A. Fundamentals of implant

dentistry: surgical principles. 1st ed. USA: Quintessence

Publishing Co., Inc.; 2017. p. 104-22.

21. Ghanaati S, Booms P, Orlowska A, Kubesch A, Lorenz J, Rutkowski

J,etal. Advanced platelet-rich fibrin: a new concept for cell-

based tissue engineering by means of inflammatory cells. J

Oral Implantol. 2014;40(6):679-89. http://dx.doi.org/10.1563/

aaid-joi-D-14-00138. PMid:24945603.

22. Meredith N, Book K, Friberg B, Jemt T, Sennerby L. Resonance

frequency measurements of implant stability in vivo. A cross-

sectional and longitudinal study of resonance frequency

measurements on implants in the edentulous and partially

dentate maxilla. Clin Oral Implants Res. 1997;8(3):226-33. http://

dx.doi.org/10.1034/j.1600-0501.1997.080309.x. PMid:9586467.

23. Misch CE, Wang HL, Misch CM, Sharawy M, Lemons J, Judy

KWM. Rationale for the application of immediate load in implant

dentistry: part I. Implant Dent. 2004;13(3):207-17. http://dx.doi.

org/10.1097/01.id.0000140461.25451.31. PMid:15359155.

24. Baltayan S, Pi-Anfruns J, Aghaloo T, Moy PK. The Predictive

value of resonance frequency analysis measurements in the

surgical placement and loading of endosseous implants. J Oral

Maxillofac Surg. 2016;74(6):1145-52. http://dx.doi.org/10.1016/j.

joms.2016.01.048. PMid:26917203.

25. De Oliveira Fernandes GV, Malta Santos NB, Correia de Sousa MF,

Fernandes JCH. Liquid platelet-rich fibrin coating implant surface

to enhance osseointegration: a double-blinded, randomized

split- mouth trial with 1-year follow-up. Int J Oral Maxillofac

Implants. 2022;37(1):159-70. http://dx.doi.org/10.11607/

jomi.9107. PMid:35235635.

26. Qin D, Hua F, Yue H, Yan Q, He H, Tu YK. The reporting

and methodological quality of split-mouth trials in oral

implantology: A methodological study. Clin Oral Implants

Res. 2022;33(12):1282-92. http://dx.doi.org/10.1111/clr.14011.

PMid:36251569.

27. Gotfredsen K, Wiskott A, Working Group 4. Consensus report

- reconstructions on implants. The Third EAO Consensus

Conference 2012. Clin Oral Implants Res. 2012;23(Suppl

6):238-41. http://dx.doi.org/10.1111/j.1600-0501.2012.02549.x.

PMid:23062146.

28. Liu W, Cai H, Zhang J, Wang J, Sui L. Effects of immediate and

delayed loading protocols on marginal bone loss around implants

in unsplinted mandibular implant-retained overdentures:

a systematic review and meta-analysis. BMC Oral Health.

2021;21(1):122. http://dx.doi.org/10.1186/s12903-021-01486-3.

PMid:33731092.

29. Refaie A, Zohdy M, Aboelfadl A, Wahsh M. Effect of different

immediate implant loading protocols on peri implant soft

tissue health. Braz Dent Sci. 2020;23(4):7p. http://dx.doi.

org/10.14295/bds.2020.v23i4.1998.

30. Aldhohrah T, Mashrah MA, Wang Y. Effect of 2-implant

mandibular overdenture with different attachments and loading

protocols on peri-implant health and prosthetic complications:

a systematic review and network meta-analysis. J Prosthet

Dent. 2022;127(6):832-44. http://dx.doi.org/10.1016/j.

prosdent.2020.12.016. PMid:33546861.

31. Masuki H, Okudera T, Watanebe T, Suzuki M, Nishiyama

K, Okudera H, et al. Growth factor and pro-inflammatory

cytokine contents in platelet-rich plasma (PRP), plasma rich in

growth factors (PRGF), advanced platelet-rich fibrin (A-PRF),

and concentrated growth factors (CGF). Int J Implant Dent.

2016;2(1):19. http://dx.doi.org/10.1186/s40729-016-0052-4.

PMid:27747711.

32. Shetye AG, Rathee M, Jain P, Agarkar V, Kaushik S, Alam M. Effect

of advanced platelet-rich fibrin and concentrated growth factor

on tissues around implants in maxillary anterior region. J Indian

Prosthodont Soc. 2022;22(2):169-78. http://dx.doi.org/10.4103/

jips.jips_301_21. PMid:36511028.

33. Herrero-Climent M, Santos-García R, Jaramillo-Santos R, Romero-

Ruiz MM, Fernández-Palacin A, Lázaro-Calvo P,etal. Assessment

of Osstell ISQ’s reliability for implant stability measurement: a

cross-sectional clinical study. Med Oral Patol Oral Cir Bucal.

2013;18(6):e877-82. http://dx.doi.org/10.4317/medoral.19120.

PMid:24121909.

34. Javed F, Romanos GE. The role of primary stability for

successful immediate loading of dental implants. A literature

review. J Dent. 2010;38(8):612-20. http://dx.doi.org/10.1016/j.

jdent.2010.05.013. PMid:20546821.

35. Jacobs R, Salmon B, Codari M, Hassan B, Bornstein MM.

Cone beam computed tomography in implant dentistry:

recommendations for clinical use. BMC Oral Health. 2018;18(1):88.

http://dx.doi.org/10.1186/s12903-018-0523-5. PMid:29764458.

36. Awaad NM, Elsadek MA, El Kady DM. Prosthetic maintenance

assessment for implant fixed complete dentures and implant

overdentures: a randomized clinical trial. Braz Dent Sci.

2023;26(2):e3736. http://dx.doi.org/10.4322/bds.2023.e3736.

37. Hasan I, Dominiak M, Blaszczyszyn A, Bourauel C, Gedrange T,

Heinemann F. Radiographic evaluation of bone density around

immediately loaded implants. Ann Anat. 2015;199:52-7. http://

dx.doi.org/10.1016/j.aanat.2014.02.009. PMid:24690291.

38. Bornstein MM, Horner K, Jacobs R. Use of cone beam computed

tomography in implant dentistry: current concepts, indications

and limitations for clinical practice and research. Periodontol

2000. 2017;73(1):51-72. http://dx.doi.org/10.1111/prd.12161.

PMid:28000270.

39. Homolka P, Gahleitner A, Kudler H, Nowotny R. A simple method

for estimating effective dose in dental CT. Conversion factors

and calculation examples for a clinical low dose protocol. Röfo

Fortschr Geb Röntgenstr Nuklearmed. 2001;173(6):558-62.

http://dx.doi.org/10.1055/s-2001-14991. PMid:11471298.

40. Genisa M, Rajion Z, Mohamad D, Pohchi A, Kadir M, Shuib S.

Effect of different angle scanning on density estimation based on

hounsfield unit on CT and CBCT. Sains Malays. 2015;44(9):1331-7.

http://dx.doi.org/10.17576/jsm-2015-4409-16.

41. Guglielmotti MB, Olmedo DG, Cabrini RL. Research on implants

and osseointegration. Periodontol 2000. 2019;79(1):178-89.

http://dx.doi.org/10.1111/prd.12254. PMid:30892769.

42. da Silva RJ, Semprini M, da Silva CHL, Siéssere S, Chimello

DT, Bataglion C, et al. Resonance frequency analysis of

overdenture retainer implants with immediate loading.

Gerodontology. 2012;29(2):e408-12. http://dx.doi.org/10.1111/

j.1741-2358.2011.00488.x. PMid:21557763.

43. Andrade GS, Kalman L, Lo Giudice R, Adolfi D, Feilzer AJ, Tribst

JPM. Biomechanics of implant-supported restorations. Braz Dent

Sci. 2023;26(1):e3637. http://dx.doi.org/10.4322/bds.2023.

e3637.

44. Diana C, Mohanty S, Chaudhary Z, Kumari S, Dabas J, Bodh

R. Does platelet-rich fibrin have a role in osseointegration of

immediate implants? A randomized, single-blind, controlled

clinical trial. Int J Oral Maxillofac Implants. 2018;47(9):1178-88.

http://dx.doi.org/10.1016/j.ijom.2018.01.001. PMid:29402513.

Braz Dent Sci 2023 Oct/Dec;26 (4): e3987

Allah ESA et al.

Bone density and implant stability with advanced platelet-rich fibrin in immediately loaded- implant assisted mandibular overdentures

Allah ESA et al. Bone density and implant stability with advanced platelet-rich

ﬁbrin in immediately loaded- implant assisted mandibular

overdentures

45. Kobayashi E, Flückiger L, Fujioka-Kobayashi M, Sawada K,

Sculean A, Schaller B, et al. Comparative release of growth

factors from PRP, PRF, and advanced-PRF. Clin Oral Investig.

2016;20(9):2353-60. http://dx.doi.org/10.1007/s00784-016-

1719-1. PMid:26809431.

46. He L, Lin Y, Hu X, Zhang Y, Wu H. A comparative study of

platelet-rich fibrin (PRF) and platelet-rich plasma (PRP)

on the effect of proliferation and differentiation of rat

osteoblasts in vitro. Oral Surg Oral Med Oral Pathol Oral

Radiol Endod. 2009;108(5):707-13. http://dx.doi.org/10.1016/j.

tripleo.2009.06.044. PMid:19836723.

47. Öncü E, Erbeyoğlu AA. Enhancement of immediate implant

stability and recovery using platelet-rich fibrin. Int J Periodont

Restor Dent. 2019;39(2):e58-63. http://dx.doi.org/10.11607/

prd.2505. PMid:28196154.

48. Tabrizi R, Arabion H, Karagah T. Does platelet-rich fibrin increase

the stability of implants in the posterior of the maxilla? A split-

mouth randomized clinical trial. Int J Oral Maxillofac Implants.

2018;47(5):672-5. http://dx.doi.org/10.1016/j.ijom.2017.07.025.

PMid:29269149.

49. Kalash S, Aboelsaad N, Shokry M, Choukroun J. The efficiency

of using advanced PRF-xenograft mixture around immediate

implants in the esthetic zone: a randomized controlled clinical

trial. BioCensus. 2017;9(4):317-22. http://dx.doi.org/10.23805/

JO.2017.09.04.02.

50. Alhaj F, Shokry M, Attia N. The efficiency of using advanced

Platelet-Rich fibrin–Autogenous bone graft mixture around

immediately placed dental implants in mandibular molar

region: (Randomized controlled clinical trial). Egypt Dent

J. 2018;64(3):2023-35. http://dx.doi.org/10.21608/

edj.2018.76743.

51. Thor A, Rasmusson L, Wennerberg A, Thomsen P, Hirsch

JM, Nilsson B, et al. The role of whole blood in thrombin

generation in contact with various titanium surfaces.

Biomaterials. 2007;28(6):966-74. http://dx.doi.org/10.1016/j.

biomaterials.2006.10.020. PMid:17095084.

52. El Shafei SF, Raafat SN, Amin AH, Rizk FN. Effect of local

application of platelet-rich fibrin scaffold loaded with

simvastatin on peri-implant bone changes. J Indian Prosthodont

Soc. 2022;22(2):152-60. http://dx.doi.org/10.4103/jips.

jips_258_21. PMid:36511026.

53. To M, Su CY, Hidaka K, Okudera T, Matsuo M. Effect of advanced

platelet-rich fibrin on accelerating alveolar bone formation in

dogs: a histological and immunofluorescence evaluation. Anat

Sci Int. 2019;94(3):238-44. http://dx.doi.org/10.1007/s12565-

019-00479-1. PMid:30747352.

Eman Sabry Ata Allah

(Corresponding address)

Kafr El-shiekh University, Faculty of Dentistry, Department of Prosthodontics, Kafr

El-shiekh, Egypt.

Email: e.sabry.575@gmail.com

Date submitted: 2023 Aug 08

Accepted submission: 2023 Oct 16