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.2024.e4186
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Braz Dent Sci 2024 Apr/June;27 (2): e4186
This is an Open Access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in
any medium, provided the original work is properly cited.
Effect of loading protocol on peri-implant marginal bone loss:
randomized clinical trial
Efeito do protocolo de carregamento na perda óssea marginal peri-implantar: ensaio clínico randomizado
Yasser Sobhy ABDUL-RAOUF1 , Amina Mohamed HAMDY1 , Maged Mohamed ZOHDY1 , Soha OSAMA NABIH1
1 - Ain Shams University, Faculty of Dentistry, Fixed Prosthodontics. Cairo, Egypt.
How to cite: Abdul-Raouf YS, Hamdy AM, Zohdy MM, Osama Nabih S. Effect of loading protocol on peri-implant marginal bone loss:
randomized clinical trial. Braz Dent Sci. 2024;27(2):e4186. https://doi.org/10.4322/bds.2024.e4186
ABSTRACT
Objective: This clinical study was conducted to evaluate the effect of loading protocol using hybrid ceramic resinous
material on marginal bone loss. Material and Methods: This study was conducted in the xed prosthodontics
department, at Ain Shams University on 30 titanium endosseous tapered threaded implants which were placed
in 30 patients in the upper premolar area. Patients were divided randomly according to the loading protocol
into 3 groups (10 patients each): Group I (IFLV): patients received CAD/CAM polymer inltrated ceramic
(VITA-ENAMIC) crowns (immediate functional loading), Group II (IFLP): patients received CAD/CAM PMMA
crowns (in occlusion for 3 months) followed by CAD/CAM polymer inltrated ceramic (VITA-ENAMIC) crowns
(functional loading), and Group III (INFLP): patients received CAD/CAM PMMA crowns (out of occlusion for
3 months) followed by CAD/CAM VITA-ENAMIC crowns (functional loading). Results: After three months;
the highest value of marginal bone loss (mm) was found in IFLV, followed by IFLP, while the lowest value was
found in INFLP. After six months, the highest value was found in IFLP, followed by IFLV, while the lowest value
was found in INFLP. Also, after twelve months, the highest value was found in IFLV, followed by IFLP, while the
lowest value was found in INFLP. Marginal bone loss values were within the accepted values for clinical success
for all the tested groups. Conclusion: Immediate non-functional loading provided more acceptable outcomes
than immediate functional loading. Also, immediately functional and non-functional implant loading using hybrid
ceramic as permanent material has shown promising results with proper patient selection.
KEYWORDS
Bone loss; CAD/CAM; Ceramic; Hybrid; Loading.
RESUMO
Objetivo: Este estudo clínico foi realizado para avaliar o efeito do protocolo de carregamento utilizando material
resinoso cerâmico híbrido na perda óssea marginal. Material e Métodos: Este estudo foi realizado no departamento
de prótese xa da Universidade Ain Shams em 30 implantes endósseos cônicos de titânio que foram instalados
em 30 pacientes na região de pré-molares superiores. Os pacientes foram divididos aleatoriamente de acordo
com o protocolo de carregamento em 3 grupos (10 pacientes cada): Grupo I (IFLV): os pacientes receberam
coroas usinadas em CAD/CAM de cerâmica inltrada com polímero (VITA-ENAMIC) (carga imediata), Grupo II
(IFLP): os pacientes receberam coroas usinadas em CAD/CAM de PMMA (em oclusão por 3 meses) seguidas por
coroas de cerâmica inltrada com polímero (VITA-ENAMIC) (carga funcional), e Grupo III (INFLP): os pacientes
receberam coroas usinadas em CAD/CAM de PMMA (infraoclusão por 3 meses) seguido de coroas de VITA-ENAMIC
(carga funcional). Resultados: Após três meses; o maior valor de perda óssea marginal (mm) foi encontrado
no IFLV, seguido pelo IFLP, enquanto o menor valor foi encontrado no INFLP. Após seis meses, o maior valor
foi encontrado no IFLP, seguido do IFLV, enquanto o menor valor foi encontrado no INFLP. Além disso, após
doze meses, o maior valor foi encontrado no IFLV, seguido pelo IFLP, enquanto o menor valor foi encontrado no
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Abdul-Raouf YS et al.
Effect of loading protocol on peri-implant mar ginal bone loss: randomized clinical trial
Abdul-Raouf YS et al. Effect of loading protocol on peri-implant marginal bone loss:
randomized clinical trial
INTRODUCTION
Loss of teeth may affect the quality of
patient’s life esthetically, functionally, and
biologically [1]. Traditionally, these teeth were
restored with either a fixed or a removable
prosthesis. However, both of these restorative
options have some drawbacks related to the
health of the oral tissues and reduced patient
satisfaction [2]. Therefore, dental implants were
introduced to provide an alternative for replacing
missing teeth [3]. Implants come in a variety of
shapes and sizes to suit the missing teeth and
the types of prostheses used. Their surfaces
have been improved to enhance the Osseo-
integration. Instead of surfaces being smooth or
machined, they are roughened by sandblasting
and acid etching, which increases the surface
area to which bone can attach [4]. The implant
design “threaded type implants” are generally
recommended due to their mechanical retention
properties, which minimize micromotion and
improve primary stability [5].
In natural teeth, the impact energy of the
masticatory forces is absorbed by the periodontal
ligament [6]. Dental implants are not surrounded
by a resilient periodontal ligament therefore the
forces will be transmitted directly to the bone [7].
The increased amount of stress on the bone can
induce resorptive remodeling and mechanical
failure of the implant [8]. The desire for fewer
surgical interventions and shorter implant
treatment times has led to the development
of revised placement and loading protocols.
A healing period of 4–6 months was proposed to
ensure osseointegration of dental implants [9].
With the improvements in oral implantology,
the traditional protocol for implant dentistry
has been constantly reevaluated. Recent steps
include a reduction of the treatment time through
the immediate placement of implants into fresh
extraction sockets [10] and by loading the
implants immediately [11]. Immediate loading
protocols have been extensively discussed in the
literature and found to be a viable treatment
approach in selected cases [11]. This clinical
study was conducted to evaluate the effect of
loading protocol using hybrid ceramic material
on marginal bone loss using three protocols:
Immediate functional implant loading - using
hybrid ceramic material, Immediate functional
implant loading - using PMMA provisional
material followed by delayed functional loading
using hybrid ceramic material, Immediate
non-functional implant loading - using PMMA
provisional material followed by delayed
functional loading using hybrid ceramic material.
The null hypothesis of this research suggested
that different immediate functional loading
protocols wouldn’t have an effect on the marginal
bone loss.
MATERIAL & METHODS
This investigation was a randomized
double-blinded clinical trial where both the
clinician and the patients were blinded during
the randomization process . Patients were
assigned into three groups using simple allocation
sequence concealment by a computer- generated
random number sequence . It was conducted in
the outpatient clinic of the xed prosthodontics
department, Ain Shams University on a series
of 30 titanium endosseous tapered threaded
implants (two-piece) which were placed in
30 patients in the upper premolar area. It was
approved by the ethics committee of the faculty
of dentistry Ain Shams University (FDASU-
RECR021805). A total sample size of 30 patients
(10 in each group) was sufficient to detect a
power of 71%, and a signicance level of 5%.
It was calculated by G*Power (Version 3.1.9.2).
Patients were selected according to certain
inclusion and exclusion criteria. Inclusion criteria
involved: patients between the age of 25 and 40,
systemically healthy, missing upper premolar
not less than 1 year, bounded by natural teeth
anteriorly and posteriorly, sufcient bone width
INFLP. Os valores de perda óssea marginal estavam todos dentro de valores aceitáveis para sucesso clínico para
todos os grupos testados. Conclusão: A carga funcional não imediata proporcionou resultados mais aceitáveis
do que a carga imediata. Além disso, o carregamento funcional imediato e não imediato de implantes utilizando
coroas nais de cerâmica híbrida mostrou resultados promissores com a seleção adequada dos pacientes.
PALAVRAS-CHAVE
Reabsorção óssea; CAD/CAM; Cerâmica; Híbrido; Carregando.
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Abdul-Raouf YS et al.
Effect of loading protocol on peri-implant mar ginal bone loss: randomized clinical trial
Abdul-Raouf YS et al. Effect of loading protocol on peri-implant marginal bone loss:
randomized clinical trial
and height to receive an implant of minimum
diameter of 3.75 mm, bone quality either D2 or
D3 as assessed by CBCT (determined using the
Hounseld scale, which is a quantitative scale
provides an exact density value for each tissue
type. On the Hounseld scale, the air has a value
of −1000 (black on the grayscale), while bone
presents values from +700, for spongy bone, to
+3000, for dense bone), good oral hygiene with
healthy gingiva, canine-guided occlusion, and
the implant should be placed in healed bony site
with a ridge width of at least 5.5mm. While the
exclusion criteria were: patients with metabolic
bone disorders, presence of para-functional habits
such as bruxism, deep bite, smokers, and and
mentally disturbed patients.
Implants were placed in the upper premolar
area. The patients were divided randomly
(randomized double blinded clinical trial)
according to the loading protocol into 3 groups
(10 patients each): Group I (IFLV): patients
received CAD/CAM polymer inltrated ceramic
VITA-ENAMIC crowns (VITA Zahnfabrik H.
Rauter GmbH & Co.KG Spitalgasse Germany)
(immediate functional loading), Group II (IFLP):
patients received CAD/CAM PMMA crowns (Vipi
block, vipi, Brasil) (in occlusion for 3 months)
followed by CAD/CAM polymer infiltrated
ceramic (VITA-ENAMIC) crowns (functional
loading), and Group III (INFLP): patients received
CAD/CAM PMMA crowns (out of occlusion
for 3 months) followed by CAD/CAM polymer
infiltrated ceramic (VITA-ENAMIC) crowns
(functional loading).
Precise medical, dental, and family histories
were taken from all patients through a direct
interview and a questionnaire sheet. Thorough
clinical examination including extra and intra-
oral examinations. Bone sounding was done to
the edentulous area and periodontal probing of
adjacent teeth. A diagnostic le of the patient and
pre-operative photographs of the patients were
performed. Clinical photographs were taken for
each patient using a digital camera including the
implant site and at least one adjacent tooth on
each side, the reference teeth should be visible
well enough to ensure comparability.
Cone beam computed tomography (CBCT)
was used to evaluate the bone height and width
in the area of interest, and also to assess the
position of the maxillary sinus and bone quality
of the alveolar ridge had been assessed. CBCT
was used to select the proper implant diameter
and length with a safety margin of intact bone
2 mm between the implant and the oor of the
maxillary sinus and 1.5 mm between the implant
and the adjacent teeth was left [12].
The planning software (Blue Sky Bio
software) was used to simulate implant placement
on the 3D model using CBCT data. Two-piece
implants (Neo CMI implant, Neo Biotech implant,
Korea) were used in the study. Implant Kit:
Neobiotech IS Full Kit ver.5 surgical tray kit
(Neobiotech Inc., Los Angeles, USA) and Dentis
simple guide surgical kit (Dr. Amr EL Khadem,
Cairo, Egypt) were used for implant placement.
Then drilling was done through the guide using
Dentis simple guide kit, as demonstrated in
Figure 1. During drilling no lateral movement
was done. Only vertical motion is allowed to
avoid detachment or fracture of the metal sleeves.
Insertion Torque was checked with the
30N/cm torque wrench, as observed in Figure 2.
A post-operative CBCT was made for the patient
after implant insertion to ensure the proper
positioning of the implant within the bone. On the
same day of the surgery, the nal impression was
taken. Single step impression technique with an
Open tray technique using vinyl polysiloxane
impression material, Panasil impression material,
(Kettenbach LP, Huntington Beach, USA) was
used. The Access hole for the impression coping
Figure 1 - Drilling through the guide.
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Abdul-Raouf YS et al.
Effect of loading protocol on peri-implant mar ginal bone loss: randomized clinical trial
Abdul-Raouf YS et al. Effect of loading protocol on peri-implant marginal bone loss:
randomized clinical trial
(transfer coping) was prepared in the rigid
impression tray. The guide screw was tightened
using the hex driver. The putty impression
material was mixed according to manufacturer
instructions and loaded in the tray at the same
time the light body impression material was auto-
mixed and applied around the impression post.
The loaded tray was seated inside the patient’s
mouth parallel to the long axis of the teeth and
held in place without exerting pressure until the
material was set.
The internal hex of the implant was irrigated
and the healing cap was screwed inside the
implant using the hex driver. The implant-level
replicas (laboratory analogs) were screwed into
the impression copings with the hex driver.
The soft tissue cast (gingival mimic) was used
for the proper emergence profile. Abutments
were rst screwed to the analogs, then occlusal
reduction for the abutments was made to create a
2mm occlusal clearance to receive the restoration.
Designing of the crowns was done using Exocad
2016 software .
In Group I (IFLV): the occlusal parameters
during the CAD procedure were adjusted to
establish a light occlusal contact in centric
maximum intercuspation. After the milling
procedure, final adjustments of the crowns
were performed inside the patient’s mouth with
200-micron articulating paper to remove any
heavy contacts. An additional occlusal checking
was performed with 40 micron and 12 micron
articulating paper respectively to ensure that
a light occlusal marking was achieved on the
implant restoration while heavy markings were
achieved by the adjacent natural teeth.
The palatal cusps of the restorations
occluded in the central cusp or the fossae of
their counterparts while the buccal cusps were
free from any contact (Figure 3).
Group II (IFLP): patients received CAD/
CAM PMMA crown (in occlusion for 3 months)
followed by CAD/CAM VITA ENAMIC crown
(functional loading).
Group III (INFLP): patients received CAD/
CAM PMMA (out of occlusion for 3 months).
The occlusal parameters during the CAD
procedure were adjusted to have no occlusal
contact in centric occlusion or lateral excursive
movements. After the milling procedure, nal
adjustments of the crowns were performed
inside the patient’s mouth with articulating paper
to ensure no contact in centric and eccentric
movements. After 3 months the crown was
replaced by CAD/CAM VITA ENAMIC crown
(functional loading) (Figure 4).
Immediate loading of the implants was done
within maximum of 2 days. After the fabrication
Figure 2 - Checking primary stability with the 30N/cm torque
wrench.
Figure 3 - Functional occlusion design.
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Abdul-Raouf YS et al.
Effect of loading protocol on peri-implant mar ginal bone loss: randomized clinical trial
Abdul-Raouf YS et al. Effect of loading protocol on peri-implant marginal bone loss:
randomized clinical trial
of the restoration, the healing caps were removed
from the patient’s mouth and the nal abutments
were removed from the cast and tightened
over the implants with the hex driver, then the
restorations were placed over the corresponding
abutments and checked for contact, occlusion
and shade. PMMA crowns were replaced after
3 months in groups INLP and IFLP by Vita
Enamic crowns after taking a new impression
and fabrication of the nal restoration.
Bone height measurements: An immediate
post-operative CBCT was taken after implant
placement to serve as a baseline for further
investigations. Three CBCTs were taken at
three months, six months, and one year.
These CBCTs were compared to the baseline
CBCT took immediately post-operative to
measure the marginal bone loss. A comparison
of marginal bone loss was performed by the
superimposition of the CBCTs and measuring the
amount of bone loss. Surface based registeration
method were used which relies on automated
superimposition to determine the best surface
t registeration .The measurements were taken
from the crest of the ridge until the apex of the
implant. The raw DICOM data set obtained from
the CBCT scanning was imported to a specialist
third party software for secondary reconstruction
and the results obtained were compared to each
other (Figures 5, 6, 7 and 8).
Statistical methods
Numerical data were presented as mean and
standard deviation values and were explored for
normality by checking the data distribution and
using the Shapiro-Wilk test. Data were normally
distributed and were analyzed using one-way
ANOVA followed by Tukey’s post hoc test for
intergroup comparisons and repeated measures
ANOVA followed by Bonferroni’s post hoc test for
intragroup comparisons. The signicance level
was set at p<0.05 within all tests. Statistical
analysis was performed with R statistical analysis
software version 4.1.3 for Windows R-core Team.
RESULTS
According to Table I and Figure 9, after three
months; the highest value of marginal bone loss
(mm) was found in group I (IFLV) (0.96±0.03),
followed by group II (IFLP) (0.94±0.03), while
the lowest value was found in group III (INFLP)
(0.57±0.06). Post hoc pairwise comparisons
showed group (III) to have a signicantly lower
value than other groups (p <0.001) while there
was no signicant difference between group I
and group II.
While after six months, the highest value was
found in group II (IFLP) (1.29±0.02), followed
by group I (IFLV) (1.28±0.07), while the lowest
value was found in group III (INFLP) (0.74±0.07).
Post hoc pairwise comparisons showed group (III)
to have a signicantly lower value than other
groups (p <0.001) while no signicant difference
was detected among group I and group II. Also,
after twelve months, the highest value was found
in group I (IFLV) (1.62±0.15), followed by group
II (IFLP) (1.61±0.15), while the lowest value was
found in group III (INFLP) (1.06±0.05). Post
hoc pairwise comparisons showed group (III)
to have a signicantly lower value than other
groups (p <0.001) while there was no signicant
difference between group I and group II.
According to Table II and Figure 10, in group
(I) (IFLV) there was a signicant difference between
values measured at different intervals (p<0.001).
Figure 4 - Non-functional occlusion design.
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Effect of loading protocol on peri-implant mar ginal bone loss: randomized clinical trial
Abdul-Raouf YS et al. Effect of loading protocol on peri-implant marginal bone loss:
randomized clinical trial
The highest value was measured after 12 months
(1.62±0.15), followed by 6 months (1.28±0.07),
while the lowest value was found after 3 months
(0.96±0.03). Post hoc pairwise comparisons
showed values measured at different intervals to be
signicantly different from each other (p<0.001).
Figure 5 - Buccal, palatal, mesial and distal CBCT measurements at baseline.
Figure 6 - Buccal, palatal, mesial and distal CBCT measurements at 3 months.
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Effect of loading protocol on peri-implant mar ginal bone loss: randomized clinical trial
Abdul-Raouf YS et al. Effect of loading protocol on peri-implant marginal bone loss:
randomized clinical trial
In group (II) (IFLP) there was a signicant
difference between values measured at different
intervals (p<0.001). The highest value was
measured after 12 months (1.61±0.15), followed
by 6 months (1.29±0.02), while the lowest value
was found after 3 months (0.94±0.03).
Figure 7 - Buccal, palatal, mesial, and distal CBCT measurements at 6 months.
Figure 8 - Buccal, palatal, mesial, and distal CBCT measurements at 12 months.
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Abdul-Raouf YS et al.
Effect of loading protocol on peri-implant mar ginal bone loss: randomized clinical trial
Abdul-Raouf YS et al. Effect of loading protocol on peri-implant marginal bone loss:
randomized clinical trial
In group (III) (INFLP) there was a signicant
difference between values measured at different
intervals (p<0.001). The highest value was
measured after 12 months (1.06±0.05), followed
by 6 months (0.74±0.07), while the lowest value
was found after 3 months (0.57±0.06).
DISCUSSION
Implants with platform switched design was
used in this study in order to switched implants
maintain better bone Levels [13]. The maxillary
premolar area was chosen as the area of interest in
the study as it combines the high concern of both
esthetics and function [14]. Flapless technique,
surgical stents and guided surgeries based on
CBCT images allowed ideal placement of implant
according to the the planned restorations to
facilitate the establishment of favorable forces on
the implant and prosthetic part as well as ensure
favorable esthetic outcome [15,16].
All patients received the same treatment
protocol performed by a team of implantologist,
periodontist and laboratory technician. There was
a lack of standardized method in evaluation of the
marginal bone loss in the previous literature [17].
However, CBCT software was able to superimpose
the different 3D images to provide an accurate
measurements of the amount of bone loss during
the one year follow up period of the study [15].
Temporary crown materials have routinely
been used for immediate restoration and
immediate loading of dental implants as they
are well known to develop soft tissue contours
and maintain the inter dental papilla during
Table II - Mean, Standard deviation (SD) values for intragroup comparison of marginal bone loss (mm)
Groups
Marginal bone loss (mm) (Mean ± SD)
p-value
3 months 6 months 12 months
Group (I) 0.96±0.03C1.28±0.07B1.62±0.15A<0.001*
Group (II) 0.94±0.03C1.29±0.02B1.61±0.15A<0.001*
Group (III) 0.57±0.06C0.74±0.07B1.06±0.05A<0.001*
Means with different superscript letters within the same row are statistically significantly different*. significant (p ≤ 0.05). ns: non-significant
(p>0.05).
Figure 9 - Bar chart showing average marginal bone loss (mm) in
different groups.
Figure 10 - Bar chart showing average marginal bone loss (mm) in
different intervals.
Table I - Mean, Standard deviation (SD) values for the intergroup comparison of marginal bone loss (mm)
Time
Marginal bone loss (mm) (Mean ± SD)
p-value
Group (I) Group (II) Group (III)
3 months 0.96±0.03A0.94±0.03A0.57±0.06B<0.001*
6 months 1.28±0.07A1.29±0.02A0.74±0.07B<0.001*
12 momths 1.62±0.15A1.61±0.15A1.06±0.05B<0.001*
Means with different superscript letters within the same row are statistically significantly different *. significant (p ≤ 0.05). ns: non-significant
(p>0.05).
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Effect of loading protocol on peri-implant mar ginal bone loss: randomized clinical trial
Abdul-Raouf YS et al. Effect of loading protocol on peri-implant marginal bone loss:
randomized clinical trial
the healing period [14]. PMMA is one of the
most widely used industrial polymeric materials
because of its good biocompatibility, reliability,
dimensional stability, absence of taste, odor,
tissue irritation and toxicity, insolubility in
body uids, relative ease of manipulation, good
aesthetic appearance, and color stability [18,19].
It is supplied in the form of blanks. It has a
modulus of elasticity of 3 GPa [20].
The null hypothesis was rejected as the
different immediate functional loading protocols
have variable effects on the marginal bone loss
around dental implants. In this study, groups
comparison showed a statistically signicant higher
amount of bone loss in group I and group II when
compared to group III. This is not in agreement
with Singh et al. [21]. Chrcanovic et al. [22],
Vogl et al. [23], Suito et al. [24], Sato et al. [25],
and Donati et al. [26] have found no statistically
signicant difference in marginal bone loss between
functional and non – functional loading.
This study is in agreement with
Ramachandran et al. [27] who conducted a
study in 2016 to assess the alveolar bone density
around immediate functional and immediate non-
functional loading. They found that immediate
functional loading resulted in a signicantly larger
amount of bone demineralization at the alveolar
crest when compared to immediate non-functional
loading as the micromotion caused by immediate
functional loading affects the osseointegration
by the formation of brous tissue between the
implant and the bone under functional loading
leading to more bone resorption. This study is
also in agreement with Margossian et al. [28]
who conducted a clinical study on the two-year
success rates of immediately functionally and
non-functionally loaded implants and concluded
that the success rate of immediately loaded
implants is comparable to conventional loading
if not loaded in occlusion.
Regarding PMMA restorations, our study
showed that PMMA crowns had an acceptable
amount of marginal bone loss when used in
immediate functional implant loading. This is in
accordance with Bijjargi et al. [29] who performed
a 2D finite element model to investigate the
stresses transmitted by various restorative
materials through implants in the bone. In the
acrylic crown, the forces were more evenly
distributed resulting in less stress concentration,
especially at the neck of the implant. Thus it
can be hypothesized that the lower modulus
of elasticity of the acrylic crowns will lead to a
more favorable stress distribution and ultimately
a more favorable outcome.
Regarding Vita Enamic restorations, our
study showed that Enamic crowns had an
acceptable amount of marginal bone loss when
used in immediate functional implant loading
comparable to that of PMMA temporary crowns,
this may be attributed to the shock absorbing
feature (damping effect) of these materials [30]
leading to less load transfer from the restoration
to the surrounding bone. This was in agreement
with several studies [31-34] which concluded
that polymer-based ceramic restorations have
a considerably higher capacity to dissipate
energy elastically than glass or oxide ceramic
restorations. Vita Enamic crowns in group I
showed higher values of marginal bone loss than
PMMA crowns in group II caused by the higher
modulus of elasticity for Vita Enamic crowns
than PMMA crowns with no signicant difference
between both groups.
All of the three groups showed a statistically
significant higher value of bone loss from
3 months to one year in accordance with previous
studies [15]. Mean marginal bone loss for group
I was (1.62) mm and for group II was (1.56) mm
and (1.06) mm for group III where all implants
showed marginal bone loss within the normal
accepted values (lower than 2 mm at the 1 year
follow up period) [16],
Neither implants fail nor crowns fractures
were noticed during the 1 year follow up period
showing a survival rate of 100%.
The limited number of patients, accurate
observation of patient inclusion/exclusion
criteria, the area of interest limited to the upper
premolar area, conservative surgical technique,
strict periodontal and prosthetic monitoring, and
short observation period, could be considered
important limitations and co-factors for a high
short-term successful rate observed in the study
groups.
CONCLUSION
Within the context and limitations of this
study, the following was concluded:
Statistically significant difference was
found between immediate functional and
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Effect of loading protocol on peri-implant mar ginal bone loss: randomized clinical trial
Abdul-Raouf YS et al. Effect of loading protocol on peri-implant marginal bone loss:
randomized clinical trial
non-functional loading protocols. This study
might indicate that immediate non-functional
loading provides more acceptable outcomes
than immediate functional loading. Immediate
functional and non-functional implant loading
using hybrid ceramic as permanent material has
shown promising results with proper patient
selection. Marginal bone loss values were all
within the accepted values for clinical success for
all the tested groups.
Author’s Contributions
YSAR: Conceptualization, Methodology,
Software, Validation, Formal Analysis, Investigation,
Resources. AMH: Visualization, Supervision,
Project Administration, Funding Acquisition. MMZ:
Writing – Review & Editing. SON: Data Curation,
Writing – Original Draft Preparation.
Conict of Interest
The authors declare that they have no
competing interests.
Funding
This study was self-funded.
Regulatory Statement
This research was reviewed and approved by
the ethics committee of the faculty of dentistry
Ain Shams University (FDASU-RECR021805).
List of Abbreviations
CAD/CAM: Computer Aided Design / Computer
Aided Manufacturing
PMMA: Poly Methyle Methacrylate
CBCT: Cone Beam Computed Tomography
IFLV: Immediate Functional Loading by Vita
Enamic crown
IFLP: Immediate Functional Loading by PMMA
crown
INFLP: Immediate Non-Functional Loading by
PMMA crown
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Yasser Sobhy Abdul-Raouf
(Corresponding address)
Ain Shams University, Faculty of Dentistry, Fixed Prosthodontics, Cairo, Egypt.
Email: yassnkt@gmail.com
Date submitted: 2023 Dec 09
Accept submission: 2024 Apr 05
