The Effects of Ion Beam-Assisted Deposition of Hydroxyapatite on … · 2019-06-28 · The Effects...

The Effects of Ion Beam-Assisted Deposition

of Hydroxyapatite on the Rough Surface of

endosseous Implants in Minipigs

Min-Kyoung Kim

The Graduate School

Yonsei University

Department of Dental Science

The Effects of Ion Beam-Assisted Deposition

of Hydroxyapatite on the Rough Surface of

Endosseous Implants in Minipigs

A Dissertation Thesis

Submitted to the Department of Dental Science,

the Graduate School of Yonsei University

In partial fulfillment of the

Requirements for the degree of

Doctor of Philosophy of Dental Science

Min-Kyoung Kim

September 2007

This certifies that the dissertation thesis

of Min-Kyoung Kim is approved.

Thesis Supervisor: Seong-Ho Choi

Chong-Kwan Kim

Kyoo-Sung Cho

Kyoung-Nam Kim

Yong-Keun Lee

The Graduate School

Yonsei University

September 2007

감사의감사의감사의감사의 글글글글

정말 부족한 저의 논문이 지난 3년간의 결실을 맺었습니다. 부끄러웠습니다. 그

러나 제게는 든든한 지원군이 있었습니다.

부족한 논문을 끊임없는 지도와 격려를 아끼지 않으신 최성호 교수님께 깊은

존경과 감사를 드립니다. 그리고 바쁘신 와중에도 깊은 관심과 세심함으로 작은

부분까지 챙겨주신 김종관 교수님, 조규성 교수님, 채중규 교수님, 김경남 교수님,

이용근 교수님, 그리고 미국에 계신 김창성 교수님께 진심으로 감사드립니다.

아울러 같이 실험을 도와주시고 논문 진행과정에 많은 조언을 해주신 정의원

교수님, 실험을 함께해 준 이중석 선생과 치주과 의국원들께 감사의 말씀을 전합

니다.

그리고, 이 자리에 오기까지 곁에서 든든한 힘이 되어준 이승하 원장과 나의 친

구들에게 진심으로 감사드립니다.

마지막으로 나의 든든한 버팀목 부모님과 사랑하는 나의 가족들에게 감사의 마

음을 전하며 이 논문을 바칩니다.

2007년 8월

저자 씀

i

Table of Contents

AbstractAbstractAbstractAbstract (English)(English)(English)(English) �� iii

I. Introduction �� 1

II. Materials and methods �� 4

1. Animals �� 4

2. Hydroxyapatite coating �� 4

3. Surgical protocol �� 5

4. Resonance frequency analysis (RFA) �� 6

5. Histologic analysis �� 7

III. Results �� 8

1. Clinical findings �� 8

2. Resonance frequency analysis (RFA) �� 8

3. Histologic findings�� 9

4. Histomorphometric analysis �� 10

IV. Discussion �� 12

V. Conclusion �� 16

References �� 17

Figure legends �� 22

Figures �� 24

Abstract (Korean) �� 28

ii

List of Figures

Figure 1. Photographic image of five different surface fixtures �� 24

Figure 2. Photograghic image of the implant surgery �� 24

Figure 3. Histological view of the machined surface �� 24

Figure 4. Histological view of the anodized surface �� 25

Figure 5. Histological view of the anodized plus IBAD surface �� 25

Figure 6. Histological view of the SLA surface �� 26

Figure 7. Histological view of the SLA plus IBAD surface �� 26

List of Tables

Table 1. RFA value of healing periods of 4 weeks group �� 9

Table 2. RFA value of healing periods of 8 weeks group �� 9

Table 3. Bone to implant contact �� 11

Table 4. Bone density �� 11

iii

AbstractAbstractAbstractAbstract

The Effects of Ion Beam-Assisted Deposition of

Hydroxyapatite on the Rough Surface of Endosseous Implants

in Minipigs

Objectives: This study compared the effects of coating implants with

hydroxyapatite (HA) using an ion beam-assisted deposition (IBAD) method those

prepared with machined, anodized and sandblasted and large-grit acid etched (SLA)

surfaces in minipigs, and verified excellency of coating method with HA using IBAD.

Material and Methods: Four male Minipigs (Prestige World Genetics, Korea), 18

to 24 months old and weighing approximately 35 to 40 kg, were chosen. All premolars

and the first molars of the maxilla were carefully extracted on each side. The implants

were placed on the right side after a healing period of eight weeks. The implant

stability was assessed by resonance frequency analysis (RFA) at the time of placement.

Forty implants were divided into five groups; machined, anodized, anodized plus

IBAD, SLA and SLA plus IBAD surface implants. Four weeks after implantation on

the right side, the same surface implants were placed on the left side. After four weeks

of healing, the minipigs were sacrificed and the implants were analyses by RFA and

histological analysis.

Results: RFA showed a mean implant stability quotient (ISQ) of 75.625 ± 5.021,

76.125 ± 3.739 ISQ and 77.941 ± 2.947 at placement, after four weeks healing and

after eight weeks, respectively. Statistical analysis showed no significant differences

iv

in the values between the 5 groups. Neither for the time intervals could a significant

difference be found. Histological analysis of the implants demonstrated newly formed,

compact, mature cortical bone with a nearby marrow spaces. HA coating didn’t

separate from the implant surfaces coated HA using IBAD. In particular, the SLA

implants coated with HA using IBAD showed an improved contact osteogenesis, with

a coverage of the implant surface with a bone layer as a base for intensive bone

formation and remodeling. No inflammatory infiltrates were present around the

implants.

Conclusion: We could conclude that rough surface implants coated HA by IBAD

demonstrated improved biocompatibility, and clinical and histologic analysis showed

no differences with other established implant surfaces.

Key Words: ion beam-assisted deposition method, hydroxyapatite, rough surface

implant, minipigs

- 1 -

The Effects of Ion Beam-Assisted Deposition of

Hydroxyapatite on the Rough Surface of Endosseous Implants

in Minipigs

Min-Kyoung Kim, D.D.S., M.S.D.

Department of Dental Science

Graduate School, Yonsei University

(Directed by Prof. Seong-Ho Choi, D.D.S., M.S.D., Ph.D.)

I. Introduction

Over the past 20 years, the number of dental implant procedures has increased

steadily worldwide, reaching approximately one million dental implantations per year.

The clinical success of oral implants is associated with their early osseointegration.

Rough-surfaced implants favor both bone anchoring and biomechanical stability.

The surface characteristics of dental implants are recognized as one of the most critical

factors stimulating the osseointegration process (Albrektsson et al., 1981). For this

reason, several attempts have been made to modify the implant surface composition

and morphology in order to optimize implant-to-bone contact and improve

osseointegration.

Many studies have focused the effect of increasing the surface microroughness on

bone apposition (Buser 2001). Compared with other types of surfaces, a sandblasted

- 2 -

and acid-etched (SLA) surface has demonstrated enhanced bone apposition in

histomorphometric analyses (Buser et al., 1991; Cochran et al., 1998) as well as higher

removal torque values in biomechanical testing (Wilke et al., 1990; Li et al., 2002),

thereby allowing a reduced healing period of 6 weeks in patients with a normal bone

density, and exhibiting success rates of approximately 99 % after a follow-up of up to

5 years (Roccuzzo et al., 2001; Bornstein et al., 2003).

Currently, hydroxyapatite (HA) is widely used to implants as a coating material on

implants for fixation and faster bone healing (Cook et al., 1987). However, the HA

coating layer has chemical nonuniformity, poor mechanical properties and low

adhesion strength between the metal and HA coating (Van et al., 1995). To resolve

these problems, coating methods using ion beam-assisted deposition (IBAD) have

been developed (Cui et al., 1997).

In 2000, Lee et al. improved the bonding strength of plasma-sprayed HA coating

through an interlayer coating of biocompatible (Ti, Zr, Ir) oxides and (Ti, Zr) nitrates.

They are reported that the various Ca, P ratios of calcium phosphate films were

formed by e-beam evaporation, and that the films had an excellent bonding strength

and showed different dissolution behaviors depending on the Ca and P ratio (Lee et al.,

2000).

Zhao et al. reported that the IBAD methods improved the binding strength,

particularly the biological seal at the cervical level of the implant (Zhao et al., 2004).

Liu et al. suggested that IBAD enhanced the tensile bond strength which was

attributed to the possible chemical bonding (Liu et al., 2000).

- 3 -

Comut et al. reported that there were no significant differences in the orientation of

the collagen fibers but there were significant effects of inflammation on the connective

tissue attachment level around the IBAD implant (Comut et al., 2001).

Park et al. suggested a HA coating using IBAD may improve the bone response to

a grit-blasted implant surface and have synergic effects, and a thin HA coating might

have favorable effects that are independent of the causing surface roughness (Park et

al., 2005). Hence, many authors have suggested that combining rough surface and HA

deposition using an IBAD method will have synergic effects. Therefore, the

implants were coated with HA using the IBAD method and compared with machined,

anodized and SLA surface implant without a HA coating.

This study compared the effects of coating implants with hydroxyapatite (HA)

using an ion beam-assisted deposition (IBAD) method with implants prepared using

machined, anodized and SLA surfaces, and verified excellency of coating method with

HA using an IBAD.

- 4 -

II. Materials & methods

1. Animals

Four male Minipigs (Prestige World Genetics, Korea), 18 to 24 months old and

weighing approximately 35 to 40 kg, were chosen. The animals had intact dentition

and healthy periodontium. Animal selection and management, surgical protocol, and

preparation were carried out according to routines approved by the Animal Care and

Use Committee, Yonsei Medical Center, Seoul, Korea.

2. Hydroxyapatite coating (Lee et al., 2002; Park et al., 2005; Lee et al., 2003)

Preparation of the evaporant

Evaporants used for coating were made by adding a 17.5 % mass ratio of calcium

oxide (CaO) powder (Cerac, Milwaukee, WI) to HA powder (Alfa Aesar, Ward Hill,

MA). The mixture was ball milled in ethyl alcohol for 24 hours using aluminum oxide

(Al 2O3) balls as media. The powder mixtures were then sintered in air at 1,200 for ℃

24 hours to make the evaporants. Roughing evaporation was carried out using a

mechanical rotary pump to acquires an initial vacuum of 5 × 10-2 mmHg, which was

reducted to 10-7 mmHg using a cryopump (Helix Technology, Mansfield, MA). Before

deposition, the surface of the implants was cleaned for better adhesion using an ion

beam (120V, 2A) extracted from an end-hall-type ion gun (Mark II, Commomwelth

- 5 -

Scientific, Alexandria, VA). For evaporation, the voltage of the electron beam

(Telemark, Fremont, CA) was 8.5 kV. The current was initially 0.06 to 0.08 A, and

was increased to 0.15 A. The substrate holder was rotated at a speed of 8 rpm during

deposition to improve the uniformity of the coating layer. The thickness of the coating

layer, which was measured using a surface profiler (Model P-10; Tencor, Santa Clara,

CA) was 1 ㎛.

3. Surgical protocol

The teeth were extracted under general anesthesia and sterile conditions in an

operating room using Atropine 0.05 ㎎/㎏ SQ, Rompun® 2 ㎎/㎏, Ketamine 10

㎎/㎏ IV. Minipigs were placed on a heating pad, intubated, administered 2 %

enflurane, and monitored with an electrocardiogram. After disinfecting the surgical

sites, 2 % lidocane HCl with epinephrine 1:100,000 were administered by infiltration

at the surgical sites. Crevicular incisions were made, and all premolars and the first

molar were carefully extracted on right and left sides. Prior to extraction, P2-P4 and

M1 were sectioned in order to avoid root fracture. The flaps were sutured with vertical

mattress 5-0 resorbable sutures (Vicryl; Ethicon, Norderstedt, Germany). On the day

of surgery the dogs received antibiotics Cefazoline 10 ㎎/㎏ IV.

The implants were placed on the right side using the same surgical conditions as

used for tooth extraction, after a healing period of 8 weeks. A crestal incision was

made in an attempt to preserve the keratinized tissue. The mucoperiosteal flaps were

- 6 -

carefully reflected on the buccal and palatal aspects. The edentulous ridge was

carefully flattened on each side of the posterior maxilla preparing the implant sites

with spiral drills and taps. The implant stability was assessed by resonance frequency

analysis (RFA) at the time of placement. The flaps were closed with 5-0 resorbable

sutures. The post-operative care was carried out as for tooth extraction. The sutures

were removed after 7 to 10 days. A soft diet was provided throughout the study period.

Forty implants in this study were divided into 5 groups; machined, anodized,

anodized plus IBAD, SLA and SLA plus IBAD surface implants (Figure 1, 2). Four

weeks after implantation on the right side, the same implants were placed on the left

side. After 4 weeks of healing, the minipigs were sacrificed by an overdose of the

anesthetic drugs, and resonance frequency analysis, histologic analysis were

performed. The sections were analyzed under a microscope for any new bone

formation, bone to implant contact and bone density. Block sections including the

segments with implants were preserved and fixed in 10 % neutral buffered formalin.

The specimens were dehydrated in ethanol, embedded in methacrylate, and

sectioned in mesio-distal plane using a diamond saw (Exakt®). From each implant site,

the central section was reduced to a final thickness of approximately 20㎛ by

microgrinding and polishing with a cutting-grinding device (Exakt®). The sections

were stained in hematoxiline-eosine.

4. Resonance frequency analysis (RFA)

- 7 -

RFA was performed to measure implant stability using an OsstellTM mentor

instrument (Integration Diagnostics AB, Göteborg, Sweden). Implant stability was

measured in implant stability quotient (ISQ) units and was registered two times during

the treatment: (1) at implant placement, (2) sacrificement time. Attach the

measurement probe directly to the instrument. Attach a Smartpeg to an implant. Turn

on the instrument by pressing any key. Hold the probe steadily, aiming the probe tip at

the small magnet on the top of the Smartpeg, as close as possible without touching it.

When the ISQ-value is detected, the instrument beeps and presents the value. Short

beeps are signalling the measurements. The mean ISQ values were calculated for each

minipig and time point.

5. Histologic analysis

The general histological findings were observed using stereoscope and microscope.

The histomorphometric measurements were performed.

Bone-to-implant contact was measured using the most coronal two threads and the

most apical two threads and the bone density was measured within the same area.

- 8 -

III. Results

1. Clinical findings

During the postoperative healing period, healing was uneventful but 8 fixtures

failed; one from each of the machined, anodized and SLA plus IBAD, and two from

the SLA, and three from anodized plus IBAD surfaces. There were no signs of

inflammation observed around implants.

2. Resonance frequency analysis (RFA)

RFA showed a mean implant stability quotient (ISQ) of 75.625 ± 5.021, 76.125 ±

3.739 ISQ and 77.941 ± 2.947 ISQ at placement, after four weeks healing and after

eight weeks healing respectively (Table 1, 2). There were no remarkable differences in

RFA between the 5 groups. SLA plus IBAD group showed higher RFA value than

SLA group. But statistical analysis showed no significant differences in the ISQ values

between the 5 tested surfaces. There was no difference between the tome intervals.

- 9 -

Table 1. RFA value of healing periods of 4weeks groupTable 1. RFA value of healing periods of 4weeks groupTable 1. RFA value of healing periods of 4weeks groupTable 1. RFA value of healing periods of 4weeks group

RFA at implant placementRFA at implant placementRFA at implant placementRFA at implant placement RFA at healing period of 4weeksRFA at healing period of 4weeksRFA at healing period of 4weeksRFA at healing period of 4weeks

Surface Surface Surface Surface

characteristicscharacteristicscharacteristicscharacteristics

No. of No. of No. of No. of

implantsimplantsimplantsimplants

Mean Mean Mean Mean ±±±± SD SD SD SD No. of No. of No. of No. of


Mean Mean Mean Mean ±±±± SD SD SD SD

machinedmachinedmachinedmachined 4444 78.0078.0078.0078.00 ±±±± 2.162.162.162.16 4444 75.2575.2575.2575.25 ±±±± 5.505.505.505.50

anodizedanodizedanodizedanodized 4444 77.2577.2577.2577.25 ±±±± 2.752.752.752.75 3333 78.3378.3378.3378.33 ±±±± 2.82.82.82.89999

anodized+IBADanodized+IBADanodized+IBADanodized+IBAD 4444 78.7578.7578.7578.75 ±±±± 2.502.502.502.50 3333 77.0077.0077.0077.00 ±±±± 2.62.62.62.65555

SLA SLA SLA SLA 4444 75.7575.7575.7575.75 ±±±± 3.593.593.593.59 2222 72.5072.5072.5072.50 ±±±± 3.53.53.53.54444

SLA+IBADSLA+IBADSLA+IBADSLA+IBAD 4444 70.0070.0070.0070.00 ±±±± 3.743.743.743.74 3333 76.5076.5076.5076.50 ±±±± 3.13.13.13.11111

Table 2. RFA value of healing periods of 8weeks group

RFA at implant plRFA at implant plRFA at implant plRFA at implant placementacementacementacement RFA at healing period of 8weeksRFA at healing period of 8weeksRFA at healing period of 8weeksRFA at healing period of 8weeks








machinedmachinedmachinedmachined 4444 76.7576.7576.7576.75 ±±±± 4.274.274.274.27 3333 76.676.676.676.67 7 7 7 ±±±± 1.51.51.51.53333

anodizedanodizedanodizedanodized 4444 75.5075.5075.5075.50 ±±±± 5.45.45.45.45555 4444 78.5078.5078.5078.50 ±±±± 1.291.291.291.29

anodized+IBADanodized+IBADanodized+IBADanodized+IBAD 4444 72.0072.0072.0072.00 ±±±± 9.769.769.769.76 2222 73.5073.5073.5073.50 ±±±± 4.954.954.954.95

SLA SLA SLA SLA 4444 75.2575.2575.2575.25 ±±±± 6.906.906.906.90 4444 78.7578.7578.7578.75 ±±±± 3.593.593.593.59

SLA+IBADSLA+IBADSLA+IBADSLA+IBAD 4444 77.0077.0077.0077.00 ±±±± 1.81.81.81.83333 4444 79.7579.7579.7579.75 ±±±± 1.21.21.21.26666

3. Histologic findings

No inflammatory reaction was observed around the implants except for the apical

portion of some implants. Histologic analysis of the implants demonstrated newly

- 10 -

formed, compact, mature cortical bone with a nearby marrow space (Figure 3, 4, 5, 6,

7). No apical epithelial migration was observed. In the cortical portion, bone

remodeling areas were present with many newly formed Haversian canals. Only in a

few areas of the interface was it possible to observe an osteoblast rim. In the apical

portion, newly formed bone trabeculae were present, which were composed mostly of

woven bone, and only a small quantity of preexisting lamellar bone was present. Bone

was in direct apposition to the titanium surface. In particular, the anodized, SLA

implants coated with HA using the IBAD method showed an improved characteristic

of contact osteogenesis in the soft bone, with the implant surface covered with a bone

layer as a base for intensive bone formation and remodeling after 4, 8 weeks (Figure 5,

7). Especially SLA surface implants coated with HA using the IBAD method have a

greatest effects.

The HA coating did not separate from the implant surfaces coated HA using IBAD.

The junctional epithelium established the attachment to the implant surface,

whereas the collagen fibers and fibroblasts of the connective tissue seal were oriented

parallel to the implant.

4. Histomorphometric analysis

Table 3, 4 shows the histomorphometric data from the analysis. In the bone-to-

implant contact and bone density, the SLA plus IBAD groups were greater than the

other groups. However, statistical analysis showed no significant differences in the

- 11 -

bone to implants contacts and bone density between the 5 tested surfaces. There was

no difference between the time intervals.

Table 3. Bone to implant contact

4 weeks4 weeks4 weeks4 weeks 8 weeks8 weeks8 weeks8 weeks






machinedmachinedmachinedmachined 4444 0.43 0.43 0.43 0.43 ±±±± 0.38 0.38 0.38 0.38 3333 0.42 0.42 0.42 0.42 ±±±± 0.24 0.24 0.24 0.24

anodizedanodizedanodizedanodized 3333 0.20.20.20.24444 ±±±± 0.1 0.1 0.1 0.12222 4444 0.34 0.34 0.34 0.34 ±±±± 0.3 0.3 0.3 0.35555

anodized+IBADanodized+IBADanodized+IBADanodized+IBAD 3333 0.10.10.10.14444 ±±±± 0.1 0.1 0.1 0.15555 2222 0.25 0.25 0.25 0.25 ±±±± 0.35 0.35 0.35 0.35

SLA SLA SLA SLA 2222 0.0.0.0.30303030 ±±±± 0. 0. 0. 0.10101010 4444 0.30.30.30.35555 ±±±± 0.1 0.1 0.1 0.18888

SLA+IBADSLA+IBADSLA+IBADSLA+IBAD 3333 0.45 0.45 0.45 0.45 ±±±± 0. 0. 0. 0.20202020 4444 0.70.70.70.75555 ±±±± 0.6 0.6 0.6 0.62222

Table 4. Bone density.

4 weeks4 weeks4 weeks4 weeks 8 weeks8 weeks8 weeks8 weeks








machinedmachinedmachinedmachined 4444 0.20.20.20.22222 ±±±± 0.1 0.1 0.1 0.19999 3333 0.40.40.40.43333 ±±±± 0.3 0.3 0.3 0.37777

anodizedanodizedanodizedanodized 3333 0.0.0.0.20202020 ±±±± 0.0 0.0 0.0 0.09999 4444 0.31 0.31 0.31 0.31 ±±±± 0.30 0.30 0.30 0.30

anodized+IBADanodized+IBADanodized+IBADanodized+IBAD 3333 0.10.10.10.16666 ±±±± 0. 0. 0. 0.20202020 2222 0.42 0.42 0.42 0.42 ±±±± 0.4 0.4 0.4 0.49999

SLA SLA SLA SLA 2222 0.26 0.26 0.26 0.26 ±±±± 0.17 0.17 0.17 0.17 4444 0.0.0.0.40404040 ±±±± 0.24 0.24 0.24 0.24

SLA+IBADSLA+IBADSLA+IBADSLA+IBAD 3333 0.48 0.48 0.48 0.48 ±±±± 0.2 0.2 0.2 0.23333 4444 0.0.0.0.50505050 ±±±± 0.1 0.1 0.1 0.19999

- 12 -

IV. Discussion

Hydroxyapatite (HA, Ca10(PO4)6(OH)2) is structurally and chemically similar to

the mineral constitute of the hard tissues, and is commonly used as a coating material

on titanium implants to considerably improved the biological affinity and activity to

the surrounding bone tissues. However, the commercially available plasma-sprayed

HA coating produces some defects such as poor adherence to the substrate, chemical

inhomogeneity, and high porosity (Friedman et al., 1994; Van et al., 1995). In addition,

the presence of residual stress in the HA coating results in crack nucleation due to a

large grain size and growth in the post-processing of the HA coatings, implantation

and postoperative surgery, or even in the detachment of the HA coatings fragments,

which can irritate the bone tissues. Various HA coating methods using IBAD have

been developed in an attempt to solve these problems.

The minipig model was chosen because it has a bone formation rate equal to that

of humans (Nkenke et al., 2003). Moreover, the minipig shows similar bone quality

and quantity to humans. This study used delayed-placement protocol but with a short

healing period. The implant stability values were high immediately after implant

placement but they decreased during the first 3 months of the healing period. The first

3 months after placement appear to be the the most vulnerable phase for implant

failure when unrestricted functional loading is initiated (Lazzara et al., 1998;

Roccuzzo et al., 2001). Some implants were exposed, which was attributed to the

initiation of unrestricted functional loading with an additional effect of poor oral

- 13 -

hygiene. There were some cases of failure. A maximum safety margin is only

achieved after a healing interval of 4 months. After this healing period, unrestricted

functional loading of the implants is possible with minimal potential for implant

failure (Nkenke et al., 2005).

Many investigators suggested that a higher removal torque value might lead to the

more predictable use of shorter implants, to a support of a prosthesis with fewer

implants, or to shorter healing periods. Statistical analysis did reveal any significant

differences in RFA values between the 5 tested surfaces and time intervals. This mighr

be due to small sample size. Single RFA measurements of an implant do not allow

assessment of its current status or a prediction of its performance. Repeated

measurements over a longer period of time and larger sample size would be necessary.

Other studies reported that the torque value was not a reliable predictor of the

implant survival during the follow-up period. Low torque values were not inevitably

followed by implant failure, and high torque values (> 50 Ncm) did not always

guarantee implant survival. In this study, it showed over 70 Ncm torque value. And we

found that cortical bone resorption appeared around implants. It hindered rather than

helped the success. It seemed that high torque values over 70Ncm were one of the

failure causes. Therefore, it is believed that the RFA value can only be used as an

indication for potential success.

No inflammatory reaction was observed around the implants except for the apical

portion of some implants, which might be due to sinus perforation. The HA coating

didn not separate from the implant surfaces. It seemed that HA coating method using

- 14 -

IBAD shows a increase adhesion strength between metal and HA. Bone was in direct

apposition to the titanium surface. The implants coated with HA using the IBAD

method showed an improved characteristic of contact osteogenesis, with a coverage of

the implant surface with a bone layer as a base for intensive bone formation and

remodeling in 4, 8 weeks. In particular, the SLA surface implants coated with HA

using the IBAD method showed the most significant bone formation. Significant

enhancement of new bone apposition to the SLA surface implants coated with HA

using the IBAD method as well as bone healing and contact osteogenesis was

observed at both 4 and 8 weeks. It was reported that a fibrin network is laid upon the

titanium dioxide surface and its associated adsorbed molecules, which facilitates the

attachment of local osteoblasts (Sodek and Cheifetz, 2000). SLA surface implants

coated with HA using the IBAD method would promote direct contact osteogenesis. It

was assumed that any combination effects of SLA and HA could enhance the surface

reactivity with the surrounding tissues. However, further studies will be needed to test

this hypothesis and determine the precise mechanism of the molecular interaction. The

standard SLA surface has already led to a decrease in the healing periods from 3

months to 6 weeks (Roccuzzo et al., 2001; Cochran et al., 2002). In addition, Buser et

al. reported that chemically modified SLA can allow for a further decrease in the

healing period as a routine procedure in 2004 (Buser et al., 2004).

Therefore, these results suggest that the use of SLA surface implants coated with

HA using the IBAD method might result in a reduced healing period.

The effects of the IBAD deposition method on the implant stability and

- 15 -

osseointegration were assessed in minipigs. According to the results, we could

conclude that rough surface implants coated HA by IBAD demonstrated improved

adhesion strength between metal and HA coating. And it showed no significant

differences in clinical finding, RFA value, histologic analysis with other rough surface

implant. In particular, the SLA surface implants coated with HA using the IBAD

method could reduce healing periods of the standard SLA implants. However, the

research design does not permit conclusions regarding the long-term treatment

outcome with these implants. Therefore, further longer-term studies with a larger

number of implants will be needed for clinical using.

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V. Conclusion

We could conclude that rough surface implants coated HA by IBAD demonstrated

improved biocompatibility, and clinical and histologic analysis showed no differences

with other established implant surfaces.

Especially SLA surface implants coated with HA using the IBAD method could

reduct healing periods of the standard SLA implants. But the research design does not

permit conclusions regarding long-term treatment outcome with implants. Further

long-term studies are needed for clinical using.

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REFERENCES

Albrektsson T, Branemark PI, Hansson HA, Lindstrom J (1981). Osseointegrated

titanium implants. Requirements for ensuring a long-lasting, direct bone-to-implant

anchorage in man. Acta Orthopedica Scandinavica 52(2):155-70.

Bornstein MM, Lussi A, Schmid B, Belser UC, Buser D (2003). Early loading of

titanium implants with a sandblasted and acid-etched (SLA) surface. 3-year results of

a prospective study in partially edentulous patients. International Journal of Oral &

Maxillofacial Implants 18:659–666.

Buser D (2001). Titanium for dental applications (II): implants with roughened

surfaces. In: Titanium in medicine. Brunette DM, Tengvall P, Textor M, Thomson P,

editors Berlin: Springer, pp.876-888.

Buser D, Broggini N, Wieland M, Schenk RK, Denzer AJ, Cochran DL, Hoffmann B,

Lussi A, Steinemann SG (2004). Enhanced bone apposition to a chemically modified

SLA titanium surface. Journal of Dental Research Jul;83(7):529-33.

Buser D, Schenk RK, Steinemann S, Fiorellini JP, Fox CH, Stich H (1991). Influence

of surface characteristics on bone integration of titanium implants. A

histomorphometric study in miniature pigs. Journal of Biomedical Materials Research

- 18 -

Jul;25(7):889-902.

Cochran DL, Buser D, ten Bruggenkate CM, Weingart D, Taylor TM, Bernard JP,

Peters F, Simpson JP (2002). The use of reduced healing times on ITI implants with a

sandblasted and acid-etched (SLA) surface: early results from clinical trials on ITI

SLA implants. Clinical Oral Implants Research Apr;13(2):144-53.

Cochran DL, Schenk RK, Lussi A, Higginbottom FL, Buser D (1998). Bone response

to unloaded and loaded titanium implants with a sandblasted and acid-etched surface:

a histometric study in the canine mandible. Journal of Biomedical Materials Research

Apr;40(1):1-11.

Comut AA, Weber HP, Shortkroff S, Cui FZ, Spector M (2001). Connective tissue

orientation around dental implants in a canine model. Clinical Oral Implants Research

Oct;12(5):433-40.

Cook SD, Kay JF, Thomas KA, Jarcho M (1987). Interface mechanics and histology

of titanium and hydroxyapatite-coated titanium for dental implant applications.

International Journal of Oral & Maxillofacial Implants 2(1):15-22.

Cui FZ, Luo ZS, Feng QL (1997). Highly adhesive hydroxyapatite coatings on

titanium alloy formed by ion beam assisted deposition. Journal of Materials Science.

- 19 -

Materials in Medicine Jul;8(7):403-5.

Friedman RJ, Black J, Galante JO, Jacobs JJ, Skinner HB (1994). Current concepts in

orthopaedic biomaterial and implant fixation. Instructional course lectures 43:233-55.

Lazzara RJ, Porter SS, Testori T, Galante J, Zetterqvist L (1998). A prospective

multicenter study evaluating loading of osseotite implants two months after

placement: one-year results. Journal of Esthetic Dentistry 10(6):280-9.

Lee IS, Kim HE, Kim SY (2000). Studies on calcium phosphate coating. Surface and

Coating Technology 131: 181-6.

Lee IS, Whang CN, Kim HE, Park JC, Song JH, Kim SR (2002). Various Ca/P ratios

of thin calcium phosphate films. Materials science and engineering C 22; 15-20.

Lee IS, Whang CN, Lee GH, Cui FZ, Ito A (2003). Effects of ion beam assist on the

formation of calcium phosphate film. Nuclear instruments and methods in Physics

Research B 206, 522-526.

Li D, Ferguson SJ, Beutler T, Cochran DL, Sittig C, Hirt HP (2002). Biomechanical

comparison of the sandblasted and acid-etched and the machined and acid-etched

titanium surface for dental implants. Journal of Biomedical Materials Research

- 20 -

60:325–332.

Liu JQ, Luo ZS, Cui FZ, Duan XF, Peng LM (2000). High-resolution transmission

electron microscopy investigations of a highly adhesive hydroxyapatite

coating/titanium interface fabricated by ion-beam-assisted deposition. Journal of

Biomedical Materials Research Oct;52(1):115-8.

Nkenke E, Lehner B, Fenner M, Roman FS, Thams U, Neukam FW, Radespiel-Troger

M (2005). Immediate versus delayed loading of dental implants in the maxillae of

minipigs: follow-up of implant stability and implant failures. International Journal of

Oral & Maxillofacial Implants Jan-Feb;20(1):39-47.

Nkenke E, Lehner B, Weinzierl K, Thams U, Neugebauer J, Steveling H, Radespiel-

Troger M, Neukam FW (2003). Bone contact, growth, and density around

immediately loaded implants in the mandible of mini pigs. Clinical Oral Implants

Research Jun;14(3):312-21.

Park YS, Yi KY, Lee IS, Han CH, Jung YC (2005). The effects of ion beam-assisted

deposition of hydroxyapatite on the grit-blasted surface of endosseous implants in

rabbit tibiae. International Journal of Oral & Maxillofacial Implants 20:31-38.

Roccuzzo M, Bunino M, Prioglio F, Bianchi SD (2001). Early loading of sandblasted

- 21 -

and acid-etched (SLA) implants: a prospective split-mouth comparative study.

Clinical Oral Implants Research 12:572–578.

Sodek J, Cheifetz S (2000). Molecular regulation of osteogenesis. In: Bone

engineering Davis JE, editor. Toronto: em squared inc., pp. 31-43.

Van DK, Schaeken HG, Wolke JCG, Maree HM, Habraken, Verhoeven J, Jansen JA

(1995). Influence of discharge power level on the properties of hydroxyapatite films

deposited on Ti6Al4V with RF magnetron sputtering. Journal of Biomedical Materials

Research 269-76.

Wilke HJ, Claes L, Steinemann S (1990). The influence of various titanium surfaces

on the interface shear strength between implants and bone. In: Clinical implant

materials. Adv Biomater. Vol. 9. Heimke G, Soltesz U, Lee AJC, editors. Amsterdam:

Elsevier Science Publishers B.V., pp. 309–314.

Zhao BH, Bai W, Cui FZ, Feng HL (2004). Microcosmic analysis of TCP/HA coating

with micro-pores on titanium by IBAD method. Shanghai Kou Qiang Yi Xue

Oct;13(5):385-8.

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Figure Legends

Figure 1. Photographic image of five different surface Fixtures. Machined, anodized,

anodized plus IBAD, SLA, SLA plus IBAD.

Figure 2. Photograghic image of the implant surgery. Machined, anodized, anodized

plus IBAD, SLA, SLA plus IBAD were installed.

Figure 3. Histological view of the machined surface.

a. Overall view. (magnification ×8)

b. Newly formed bone covers most of the rough surface of the implant and the

existing bony compartment. (magnification ×100)

Figure 4. Histological view of the anodized surface.

a. Overall view. (magnification ×8)

b. A thin rim of newly formed bone is observed. (magnification ×100)

Figure 5. Histological view of the anodized plus IBAD surface.

a. Overall view (magnification ×8)

b. New bone formation occurs from the surface of the implant to the lateral direction.

(magnification ×100)

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Figure 6. Histological view of the SLA surface.


b. Thick dense bone is observed around the implants and nearby marrow bone


Figure 7. Histological view of the SLA plus IBAD surface.


b. Improved characteristic of contact osteogenesis, with coverage of the implant

surface with a bone layer as a base for intensive bone formation and remodeling.


c. The osteoblasts are arranged along the implant surface followed by newly formed

osteoid alongside the woven bone parallel to the osteoblasts. (magnification ×200)

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Figures I

Figure Figure Figure Figure 1111

Figure Figure Figure Figure 2222

Figure Figure Figure Figure 3 (a, b)3 (a, b)3 (a, b)3 (a, b)

(a) (b)

- 25 -

Figures II

Figure 4. (a, b)

(a) (b)

Figure 5. (a, b)

(a) (b)

- 26 -

Figures III

Figure 6. (a, b)

(a) (b)

Figure 7. (a, b,c)

(a) (b)

- 27 -

Figures IV

(c)

- 28 -

국문요약국문요약국문요약국문요약

거친표면거친표면거친표면거친표면 매식체에매식체에매식체에매식체에 ion beam assisted deposition ion beam assisted deposition ion beam assisted deposition ion beam assisted deposition법으로법으로법으로법으로

수산화인회석수산화인회석수산화인회석수산화인회석 처리처리처리처리 시의시의시의시의 효능효능효능효능

< 지도교수 최성호최성호최성호최성호 >

연세대학교 대학원 치의학과

김김김김 민민민민 경경경경

현재 65% 이상의 일반의들이 임상에서 통상적인 치료로 치과 임플란트를

제공하고 있을 정도로 임프란트는 보편적인 치료가 되었다. 기존 임프란트에 더

빠른 치유와 확실한 골유착을 위한 여러 시도가 시행되고 있다. 이 연구의 목적은

거친 표면 임프란트에 수산화인회석을 ion-beam assisted deposition법으로 처리

시의 임상적, 조직학적 효능에 대하여 비교, 분석하는 것이다.

총 4마리의 미니 돼지에서, 모든 상악 소구치와 제1대구치를 발거하고

8주동안 치유시킨 후, machined, anodized, sandblasted and acid-etched (SLA)

표면군과 anodized 표면과 SLA 표면에 수산화인회석을 ion-beam assisted

deposition (IBAD) 법으로 처리한 임프란트군을 식립하여, 4주, 8주 치유 후

희생하여 resonance frequency analysis (RFA) 분석과 조직학적 및 조직계측학적

분석을 시행하였다.

실험 결과, SLA표면에 수산화인회석을 IBAD 법으로 처리한 군이 높은 결과를

보이나 RFA value에서는 통계학적인 차이를 보이지는 않았다. 조직학적으로는

염증소견은 없고 전반적인 골치유 양상과 골재생이 보였으며, 8주군은 4주군에

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비하여 좀 더 성숙된 양상을 보였다. 모든 군에서 상당량의 신생골과 골유착이

관찰되었다. 특히 SLA 표면에 수산화인회석을 IBAD법으로 처리한 군에서는

개선된 접촉 골재생 (contact osteogenesis) 양상을 보이고 있다. 이는 치유기간의

단축을 유도할 수 있는 가능성을 제시하고 있다.

이상의 결과를 통해, SLA 표면에 수산화 인회석을 IBAD 법으로 처리를 하면

수산화 인회석의 금속과의 결합력을 증가시켜 코팅력을 개선시킬 수 있다는

결론을 얻었다.

핵심되는핵심되는핵심되는핵심되는 말말말말 : ion-beam assisted deposition, 수산화인회석, 거친표면 임플란트, 미니돼지

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