[e-mail]

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??????(1)
Radiation Biology ??????
????? ?????? ?????
07-31211012755
yukkwa_at_kmu.edu.tw
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1. ????
2. ??
3. ????

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References
1. Harring JI Jansen L Dental radiography-
principle techniques 2nd edition, Chapters
2,3,5-9, 22, 23 p. 11-34, 35-46, 63-80, 81-90,
91-107, 108-122, 123-153, 342-362, 363-383
2. Eric Whaites Essentials of dental radiography
radiology 3rd edition, Chapter 5, p.
33-49
3. ??? ?????? 1st edition, p. 109-13
4. White Pharoah Oral radiology principle
interpretation, 5th edition, Chapter 6, p.
94-109
5. Kaohsiung Medical University, Oral Pathology
Department
6. Manufacturers data sheet
7. Cha JY, Mah J, Sinclair P. Incidental findings
in the maxillofacial area with 3- dimensional
cone-beam imaging. Am J Orthod Dentofacial Orthop
20071327-14
8. Web et al. Background radiation levels
medical exposure in Australia. Radiation
Protection in Australia. 19991525-32
9. Farman AG. ALARA still applies. Oral Surg Oral
Med Oral Pathol Oral Radiol 2005100395-6
10. White Pharoah Oral radiology principle
interpretation, 6th edition, Chapter 2, p.
19-22
11. http//www.icrp.org/ICRP publication 125
12. zh.wikipedia.org/zh-tw
13. big5.ce.cn
14. tupian.baike.com
15. www.fly168.com.tw/
16. What you need to know about cancer. Sci Am
199628928-119
4
????????-??(1)

• ??(Sv)??????SI??,1985?????????(rem)? 1??100??
  Sievert????????????????????????????,?????????????
  ,??1928???????X?????????????1950??? ICRP
  (International Commission of Radiological
  Protection??????????)???

Ref 11
5
????????-??(2)

• ?????????????? ? ????????????????/??????/?(???
  ???????1? 8760 h)

6
??????(1)

• ????????????????????????????2.4???(mSv),????????
  ????????????????gtgt??????2000???,????????????????
  ????????,?????5µSvgt??????,0.04-1mSv?????
• ????????????????????????????(????????260mSv
  )????????????????????????????

7
??????(2)

• ??????????,???????????????
• ?????????????????????????
• ??????
• ?????????????????????????
  ,???????????????????
• ???????(3)
• ???????
• ????????????
• ????????(???????)
• ???????????????????????

8
??????

• ????????????????????????????????????????????????(
  ???????),???????????(????????)???????,???????????
  ???????,??????????-238??45??????,???????????12.5
  ????-40????????8
• ???????????-14(????)??-226(?-238?????)??-222(?-22
  6?????)???????????,????????????

9
????????

• ???????????(??????),???????,??????????????????????
  30????-40(40K)?10??(10-9g)?-14(14C)?
• ????????????????????-40,???4,000?40K?????,???????
  ????????????40K???ß?????14C?10?,14C?????????ß??1,
  200?
• ???14C????????????,??????DNA??????DNA??
  14C????50???,?????????

10

• ?????? ????34???X??????????????????2.0???????X
  ?????????? 0.06???---??????????34???X??(0.06 x
  34 2.04mSv)40????1334???X????(40 x 2/0.06
  1333.3mSv)
• ??????-??,???? 0.05???

Ref 15
11

• ?????????? ??0.0165?????????ICRP
  NO.26????????0.0165/??--???????????????0.0165????
  ???X???????????????--0.01?????--0.54?????--0.
  66?????--1.4???????--2.55???

12

• ??X????????????????????X??????????--
  ?????????????????????????,????????????????????,?
  ????????????1/180,????????1/3000??,??X??????????

13
??X??

• ??????????????????200
• PS.?????????????????????? 2/3650.0055mSv
  ???200???????1.1mSv(ICRP annual dose limit for
  general public
  1mSv)

??????????????????200
??????????????????200
Ref. 5
14
??X??
???????????????66

• ???????????????66

PS.???????? 3??????? ???66???????
0.0055 x 3 x 66 1.1mSv
Ref. 5
15
????(1)

• ???????,????????????????????????????????????????
  ????,??????????(X?????????a???p?????????)????????
  ????????????????

16
????(2)

• ??????,10?????????????????????,????????????????
  ????????????????????????

Refs 13, 14
17
????(3)

• ?????????????????,??????????????????????,?????????
  ?,????????,?????????????????-14
• ????????????,?????????????????????????????????????
  ???????????????,??-14????????,????????

18
?????????????

• 1945/7/16?????????????1989??,??????2000????????
  ?????????????80????1964/10/16???????????????,1966
  /10/27??????????,1966?12?28?????????,1967/6/17????
  ???????,1984/12/19???????????,1988?9/29/??????????
  
• ??????1054?,???????????????????????10
  ??????????,??????,??????????????
  ??????????????????(1992? (????????))
• ??????715?,?????????????????????????
  ?,??????????????????????(1990?)
• ??????210?,?????????(1996?)
• ??45?,21??????,9???????,???????????
  (1991?)
• ??45?,??????????????(1996?)
• ??6?(1998?)
• ????6?(1998?)
• ??3?(2013?)

19
????(1945-2013)
Ref 12
20
???????
????? ???? ??
???????(???????) ????????? ???,1978?????
???????(???????) ????????? ???,1981?????
???????(????????) ????????????? ???,1984?????
??????? ????????? ?1999????
???????
? ??? ? ??? ? ???
???31????435??????(2012/8)
Ref 12
21

• CHANGES IN DEOXYRIBONUCLEIC ACID (DNA) ON
  RADIATION
• Breakage of one or both DNA strands
• Cross-linking of DNA strands within the helix
  to other DNA strands or to proteins
• Change or loss of a base
• Disruption of hydrogen bonds between DNA strands

22

• CHROMOSOME ABERRATIONS ON RADIATION

A, Irradiation of cell after DNA synthesis
results single-arm (chromatid) aberration
Cell cycle. A proliferating cell moves in the
cycle from mitosis to Gap 1 (G1) to the period of
DNA synthesis (S) to Gap 2 (G2) to the next
mitosis
B, Irradiation before DNA synthesis results
double-arm (chromosome) aberration.
Refs. 10, 16
23

• DETERMINISTIC STOCHASTIC EFFECTS OF RADIATION

Radiation injury to organisms (1) Killing of
large numbers of cells (deterministic effects) or
(2) Sublethal damage to individual cells results
in cancer formation or heritable mutation
(stochastic effects).
Ref. 10
24

• RELATIVE RADIOSENSITIVITY OF VARIOUS CELLS

Ref. 10
25

• RELATIVE RADIOSENSITIVITY OF
  VARIOUS ORGANS

Ref. 10
26

• ???????????????,????????? ??0.25mm?????
• ????????????

Ref. 5
27

• ???? ????????????,?????,???
• ???(Monte Carlo)??????(transmission rate)
  ?????

P ??????,???(????????????)? ?0.1
r/?,????(??????????)??0.01 r/? d
?X?????????(??) W ????,??X??????,?mAmin/????,
???X?????mA,????,????????,
????????? U ????,??????????,???1/16,??
??,???1/4,????X???????????
Ref. 3
28

• T ????,????????????,????,?
  ?????????????,?????
• ????
• ?????T1, ?????????????????
• ????????????????????????
  ???????????????????
• (2) ?????T1/4,????????????????
• ?????????????????????????
• ?????????????
• (3) ?????T1/16,???????,????????
• ???????????????

Ref. 3
29
??X??????,??A?????,A??????X???70kVp,10mA,??????10?
?,X?????A?????1m?????A?,????????
Ref. 3
30
X???70kVp,10mA,??????10min,X?????A????(d)?1m
P??????? d W U A???? T???????
0.1
10mA 10min 100mA-min/?
Ref. 3
31
X???70kVp,10mA,??????10min,X?????A????(d)?1m
P??????? d1m d21 W 10mA 10min
100mA-min/? U A???? T???????
0.1
0.004
1/4
1
Ref. 3
32
B 0.004
0.5mm
?2
?1
Ref. 3
33

• ??X???????????,????,??????
• 4???,??16????????????,X??
• 70kVp??,100????,70kVp??,180????

• ?? ??????90?135????3???4????
• ???8???9????

Ref. 3
34

• ???????????---????? ---????X????????X??--??????
  160???/???2???80???/??, ??????????6??1.5???/??
  ,??????????

35
?? ??????????,????????????,
????X???,?????????????
?????,????,????????????
???,?????????,?????????
?,????????,????????????
??????(TLD)
Ref. 5
36

• ???? ????

37
1. Patients 2. Radiation workers 3. General
public
13 mSv in any consecutive 3 months
Ref. 2
38
Radiation absorbed dose Amount of energy absorbed
from the radiation beam per unit mass
(joules/kg) 1 Gray (Gy) 100 rads
(1cGy 1 rad)
Equivalent dose radiation absorbed dose x
quality factor (Sievert, Sv)
X-rays, ? rays, ? particles Q1 Fast neutrons
protons Q10 ? particles
Q20
Ref. 2
39
Typical Doses during Radiographic Examinations
Effective Dose (mSv)
Dental
0
2
4
6
8
10
12
Web et al. Background radiation levels and
medical exposure in Australia, Radiation
Protection in Australia, 199915(2)25-32
Ref. 8
40
Ref. 2
41
Improve in Radiation Relative Dosage for
Intra-Oral Radiography (1919-2005)
100
80
60
Relative Dose
40
20
0
1919
1925
1941
1955
1981
1991
2005
Time frame (Year)
Since 1919 a reduction in the dosage of ionizing
radiation needed to produce an intraoral x-ray
image is 2 orders of magnitude
Ref. 9
42
? ?

• ??X????????????????????????????

Ref. 5
43
Summaries
Knowing

1. ????
2. ??
3. ????

44
??X??????

• ??X?(Plain radiography)
• ??X?????(Special radiography)
• ????????(Computed tomography CT)
• ??????????(Cone-beam computed tomography CBCT)

45
??X?PLAIN RADIOGRAPHY
??X?????SPECIAL RADIOGRAPHY

• How many types?

46
????????COMPUTED TOMOGRAPHY (CT)

• Hounsfield (1972?)???????X????????,??X???????,????
  ???????????????,??????????????????????(?????????)?
  ????

Ref. 6
47
1. ????
????????????????? CB-CT????1????????Volume
Data????Multi-Slice?,?X?Y?Z?????????,??Voxel??????
,??????????????????,???,?????????????,???????????
????(MPRMulti Planar Reconstruction),?3D?????????
???
Ref. 6