01 Andreasen_Etiology and pathogenesis of traumatic dental injuries A clinical study of 1298...

8/19/2019 01 Andreasen_Etiology and pathogenesis of traumatic dental injuries A clinical study of 1298 cases_1970_Eur J Oral…

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Scand. J dent. Res. 1970: 78: 329-342

Etiology and pathogenesis oftraumatic dental injuries

A clinical study o f 1,298 cases

J. 0 NDREASENDental Department, University Hospital (Rigshospitalet), and Department of

Oral Pathology, Royal Denta l College, Copenhagen, Denmark

Abstract - The etiology and pathogenesis of traumatic dental injuries were studied onthe basis of a hospi tal material of 1,298 patients 908 males and 390 females). A totalnumber of 3,026 injured teeth were treated, including 787 primary and 2 239 permanentteeth. Repeated dental injuries were found in 24 of the cases. All traumas wereclassified according to the type of injury affecting the lips, oral mucosa, tooth-sup-porting structures, and hard dental tissues. The type of injury seems to be related tothe dentit ion, with traumas predominantly involving the tooth support ing structuresin the primary dentition. The origin of trauma was allotted into 9 groups, partly onthe basis of a presumed difference in energy of the impact as well as a difference inthe resiliency of the impact. A statistical analysis revealed significant differences in the

injury pattern between the d ifferent trauma groups. The relation between lip injuriesand injuries to tooth or tooth-supporting structures was analyzed separately. It appearedfrom this analysis that the lips may act as an impact absorber reducing the chanceof trown fracture and increasing the risk of luxation and alveolar fracture.

(Received for publication 20 February, accepted 23 April 1970

Traymatic dent al injuries leave t he den-tal grofession with severe therapeuticproblems. The population risk for sus-taining traumatic dental injuries hasbeen shown to be of an impressive mag-nitude. Thus a study by Schutzmannsky(1963) showed that 1 3 % of examinedschool children at the age of 18 yearshad been exposed to dental injuries dur-ing adolescence.

Whereas numerous studies have dealtwith the treatment procedures of theseinjuries, the etiology and pathogenesishave attracted minor interest. Consequ-ently, the purpose of the present study

was to examine the following items:'(1) The relationship between origin of

trauma and subsequent injury pat-tern to the oral structures,

(2) The interrelationship between in-juries to the mineralized oral tissues(i. e. hard dental tissue and support-in g bone) and th e sof t tissues (i. e.gingiva, oral mucosa, lips, and chin),and

3) The relationship between type ofinjury and other variables such assex, age, tooth location, and denti-tion.

Material and m ethods

The material consists of 1,298 patients

referred to t he Dental Depart ment, Uni-versity Hospital, Copenhagen, for treat-


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330 ANDREASEN

ment of traumatic dental injuries duringthe period 1955 to 1967. The admissionsto the hospital represent mainly severedental injuries whereas minor traumasare usually treated elsewhere. From therecords of these pati ents the followingvariables were registered: age, sex, his-tory of previous dental injuries, cause ofinjury, type and nu mber of teeth in-volved, an d diagnosis of in jur ies affect-ing the lips, chin, oral mucosa, tooth-supporting structures, and hard dental

tissues, using the classification systemproposed by Andreasen (1970).

Th e location of the soft tissue inju rywas registered; as involving the externalor int ernal surface of the upper o r lowerlip, the chin, or th e gingiva. Furthermore,it was noted whether the injury hadcaused swelling, abrasion, or lacerationof soft tissues.

In the statistical analysis of injurypat tern the frequencies of each typ e of

injury was first compared in two groupsusing the u-test (Hald 1952). For com-parison of injury pattern between thetraum a groups, t he U-values were squaredand added; the resulting value is ap-proximately distributed as x (Hald1952). All $compilations and statisticaltests were carried out with th e aid of a nIBM computer.7094.

Results

The sex ratio of treated patients was 908males to 390 females (2.3 : 1) and the agedistribution is shown in Table 1.

Data on previous dental injuries wereavailable f rom the records of 252 cases,and among these 60 patients (24 %) hada history of previous dental traumas.

Th e 1,298 patients represent 3,026 in-jured teeth: 787 primary and 2,239 per-manent teeth. The num ber of involvedteeth varied from one to fifteen in theindividual patient (Table 2). The loca-

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ETIOLOGY A ND PATHOGENESIS OF TRAUMATIC DENTAL INJURIES 331

Table 3

Location of t raumatized primary teeth

05+ 04+ 03+ 02+ 01+ 01 +02 +03 +04 t05

0 2 14 85 27 1 224 96 16 2 0

1 1 4 13 17 24 13 4 0 0

05- 04- 03- 02- 01- -01 -02 -03 -04 -05

* According to the H a d e ~ - u p ystem of dental designation, + signifies the maxilla, he man-dible. If the symbol is placed to the right of the figure, the right side is indicated, and viceversa. 0 before the figure indicates a primary tooth.

Table 4

Location of traumatized permanent teeth~~ ~ ~~ ~ ~

8 + 7+ 6+ 5 + 4+ 3 + 2 + I + + 1 + 2 + 3 + 4 +5 +6 +7 + 8

1 1 2 6 16 31 227 607 639 233 37 15 9 2 5 0~~ ~

0 1 2 6 4 17 6 9 1 0 6 1 0 8 62 14 5 5 8 2 0

9- 7- 6- 5- 4- 3- 2- 1- -1 -2 -3 -4 -5 -6 -7 -8

Table 5Distr ibution of injured teeth according to diagnosis and typ e of dent i t io n

(The number o f diagnoses exceeds th e number of teeth due t o mul t ipl e diagnosesfor some teeth)

All teethrimary Permanent

dentition dentition

Crown fractures without pulp exposure .... 19 (2 %) 433 (19 ) 452 (15 )Crown fractures with pulp exposure ......... 13 (2 %) 172 (8 ) 185 (6 )Crown-root fractures .............................. 14 (2 ) 108 5 ) 122 (4 )Root fractures ....................................... 31 (4 ) 156 (7 ) 187 (6%)Subluxations ............. ............. 97 (1 2%) 336 (15 %) 433 (14 )Intrusive luxations .... 61 (3 ) 186 (6%)Extrusive luxations .... ............. 265 (34 %) 630 (28 ) 895 (30 )Exarticulations ....................................... 101 (L3 ) 350 (16 ) 451 (15 )Fractures of the labial or lingual bone plate

and/or alveolar socket ........................ 33 (4 ) 109 5 ) 142 5 )Fractures of alveolar process ........ ...... 26 (3 ) 205 (9%) 231 (8%)Fractures of mandible or maxilla ............. 0 (0%) 35 (2 ) 36 (1 )

Total number of injured teeth . . . . . . . 2,239 3,026

Other irjuries or exact injury not specified 172 (29 ) 334 (15 ) 5 0 6 (20 )

-


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ANDREASEN332

tion of t he affected teeth is given inTables 3 and 4. It appears that no sidepredilection exists, an d th at t he maxil-lary central incisor region is most fre-quently involved in both dentitions. Thetype of injury sustained appears to berelated to the type of dentition, whetherpermanent or primary (Table 5). Thustooth fractures seem to be more commonin the permanent dentition while luxa-tions and especially intrusions dominatein the primary dentition. However, theseresults must be evaluated with caution,due to t he selected natu re of the material.

Complete inform ation on th e origin oftrauma was available in 725 patients.These patients represented 38 differenttypes of trauma ; however, a number ofthese included only a few cases andwere, therefore, discarded from furtheranalysis. The remaining causes of inju rywere allotted into nine main groups, andthe injury patterns were registered with-in these groups . Because of large dif-ferences in types and origin of injuriessustained in the primary and permanentdentition, sepa rate tabulations were madeaccording to type of dentition.

Table 6

Relation between origin o f t rauma and injury pat tern (primary denti t ion)

Crown OTcrown-root sfractures

Root fractures

Luxations ,

Exarticulations

Bone fractures

Gingivalinjuries

Injuries to theupper lip

Injuries to thelower lip

Injuries tothe chin

Total numberof injuries

Average numberof teeth involved

Group 1 :Fall during

No. of No. olpatients teeth

Play

3 510 10

0 00 0

24 468 3 8 8 %

5 51 7 % 10

0 00 0

10 233 4 % 4 4 %

15 295 2 % 5 6 %

5 1217 23 %

3 510 10

29 52

1.8

Group 2:Fall from a

baby carriage

No. of No. oiatients teeth

0 00 0

2 36 5 %

29 5794 % 93 %

2 46 7 %

1 43 % 7 %

9 1829 % 3 0 %13 254 2 % 4 3

4 61 3 % 10

1 13 % 2 %

31 61

2o

Group 3 :Fall on astaircase

No.of No.o,atients teeth

0 00 0

1 25 % 4 %

16 4076 77

3 61 4 % 1 2 %

3 101 4 % 19

6 1429 27

10 2248 42

6 192 9 % 3 7 %

1 45 % 8 %

21 52

2.5

Group 4 :Fa11 against

an object

No. of No. 1batients teeth

1 25 % 5 %

2 49 10

18 328 2 8 0 %

4 81 8 % 2 0 %

0 00 0

4 101 8 % 2 5 %

10 194 5 4 8 %

4 1018 % 2 5 %

0 00 0

22 40

1.8

Total

No. of No. ofJatients teeth

4 74 % 3 %

5 95 % 4 %

87 1758 4 % 8 5 %

14 231 4 % 11

4 144 % 7 %

23 6528 32

43 95

13 4718 23

5 105 % 5

47 q 47 O O

103 205

2.0


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334 A N D R E A S E N

F i g . 1 Direct too th t raum a wi thou t so f t t is sue in ju ry. Th e impact has s t ruck the p ro t rud ingmaxil lary centra l incisors .

Table 8

Chi -square values f o r compar i s on o fL in ju r y pa t t e rnEbe tween d i ff e ren t t r auma g roups

G r o u p 1 G r o u p 2 G r o u p 3 G r o u p 5 G r o u p 6 G r o u p 7 G r o u p 8

G ro up 2 Invo lved pa t ien t s 4 .38Involved tee th 16.56

Group 3 Involved patients 3.72Involv ed teeth 22.27

Gr ou p 4 Invo lved pa t ien t s 3 .15Involved teeth 11.58

Group 6 Involved patientsInvo lved tee th

G r o u p 7 Invo lved pat ientsInvolved teeth

G r o u p 8 Involved patientsInvo lved tee th

Gr ou p 9 Invo lved pa t ien t sInvo lved teeth

4.48

2.03 2.0711.96 13.15

20.16 :

16.34

5.59 18.18 14.20 19.27':'

T h e 5, 1, a n d 0.1 70 levels of s igni f icance a re deno ted *, , a n d ::'"" , r e spect ive ly. T he degreesof f r e e d o m a r e 9 for all va lues .

In Table 6 the result of this analysis is groups. "Fall from a baby carriage"listed for the primary dentition. In the (Gro up 2) show ed many cases with luxa-trauma group "fall during play" (Group tion and bone injuries. "Fall on a stair-1) crown fractures and injuries to the case" (Gr ou p 3) was characterized by achin were more common th an in other frequ ent occurrence of bone fractures


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ETIOLOGY AND PATHOGENESIS OF TRAUMATIC DENTAL IN JURIES 335

Table 9

Associat ion betw een dif ferent injuries affect ing a s ingle too th (primary denti t ion).(The frequency of associated injuries is foun d in th e vertical c olumns. Each column

represents a separate type o f injury t o th e hard dental tissues)

Crown Crown- Root Subluxa- Intrusive Extru- Exarti-Associated injuries to fractures root fractures tions luxations sive culationsinvolved teeth fractures luxations

n = 5 n = 6 n = 1 6 n = 5 8 n = 7 1 n = 1 3 9 n = 5 4

Crown fracturesCrown-root fracturesRoot fracturesSubluxations

Intrusive luxationsExtrusive luxationsExarticulationsFractures of facial

bone plateFractures of alveolar

process

Injuries to the gingivaInjuries to the upper lipInjuries to the lower lipInjuries to the chin

No. of teeth involved

0

0

06

1161

16

002

00

4

02740146

58

1 1 01 0 00 3 40 0 0

00

1 12 5

0 6 016 42 1929 67 2719 28 133 9 3

71 139 54

and lip injuries. “Fall against an object”(Group 4) revealed a n increased numberof . patients with exarticulated teeth.

similar tabulation fo r the permanentdefitition is given in Table 7. A simplefall; e.g. dur ing play, athletics, or fain-ting (Group 5) , was often followed bycrown or crown-root fractures (Fig. l),and the same injury pattern was com-mon among falls associated with bicycleor motor vehicle accidents (Group 6),and in the latter group injuries to thechin was rather common.

“Injuries during fight” (Group 7) seemto favor occurrence of fractures, luxa-tions, a nd bone fractu res at t he expenseof crown fractures. Automobil e accidents(Group 8) appeared to show a specialinjury pattern with bone fractures andinjuries to the lower lip and the chin as

the outstanding lesion. In the traumagroup encountering foreign bodies strik-ing the teeth (Group 9), crown a nd rootfractures as w t l l as injuries to the lowerlip were found very frequently.

A n analysis was performed whichcompared the injury pattern within thevarious trauma groups (Table 8). I t ap-pears from this Table that significantdifferences in injury pattern are seenbetween most of these trauma groups.

A trauma to the oral regions oftenresults in multiple types of injuries tothe individual teeth, affecting both thehard dental tissues and the supportingstructures. In Tables 9 and 10 this injurypattern is shown for the primary andpermanent dentition.

The injuries affecting th e primary den-tition are usually not of a complex


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336 ANDREASEN

Table 10

Associat ion between different injuries affect ing a s ingle to ot h (permanent denti t ion).

(The frequency of associated injuries is found in th e vertical columns . Each columnrepresents a separate type o f injury t o t he hard dental t issues)

Crown Crown- Root Subluxa- Intrusive Extrusive Exarti-Associated injuries to fractures root fractures tions luxations luxations culationsinvolved teeth fractures

n = 357 n = 63 n = 89 n = 205 n = 40 n = 415 n = 196

Crown fractures

Crown-root fractures

Root fractures

Subluxations

Intrusive luxations

Extrusive luxations

Exarticulations

Fractures of facialbone plate

Fractures of alveolarprocess

Injuries to the gingiva

Injuries to the upper lip

Injuries to the lower lip

Injuries to the chin

No. of teeth involved

008 1

32 212 135 211 0

5 3

5 059 6

194 27104 1360 27

357 63

8 321 1

3030

0 040 06 0

6 5

1 1 528 4040 10436 6314 3889 205

121

00

0

13

02614178

40

352

4000

0

24

6915324414877

415

1 1

060

00

29

762

1267031

196

naturh. However, exarticulations are re-latively often accompanied by a rootfracture. In the permanent dentition thecrown an d c;own-root fractu res are usu-ally single lesions, whereas root fractu resare oft en associated with subluxations orextrusive luxatidns. Luxation injuries aswell as exarticulations are usually single

injuries, but a n exception is noted amongintrusions where crown fractures arefrequently the associated injury.

The interrelationship between injuriesto the mineralized oral tissues (i. e. harddental tissues and supporting bone) andsoft tissues was examined separately(Tables 11 an d 12). The results of t hisanalysis are listed for injuries affectingthe primary dentition an d the permanentdentition. I t appears from Table 12 thatcrown ftacture s and root fractures, in ap-

proximately half of th e cases, are ac-companied by a corresponding lip injury.

Crown -root fractures generally show alow frequency of lip inj uries whereasinjuries to the chin are very common(Fig. 2).

Intrusive l uxations are characterized, inthe primary dentition, by a low frequency

of inju ries to the upper lip whereas ahigh frequency of injuries is recordedaffecting the lower lip or the chin.

Subluxations, extrusive luxations, andexarticulations all show, especially in themaxilla, a high frequency of correspond-ing lip in jurie s (Fig. 3 ) .

Fractu res of th e alveolar process areapparently the hard tissue injury mostoften associated with soft tissue injuries,and the majority of these fractures showcorresponding lip lesions (Fig. 4).


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ETIOLOGY AND PATHOGENESIS OF T R A U M AT I C DENTAL I N J U R I E S 337

Table 11

Rela t ion b e tw een ha rd and s o f t t i s sue in ju r i e s (p r imary den t i t io n)

Crownfractures

Crown-rootfractures

Root

fracturesSubluxations

Intrusiveluxations

Extrusiveluxations

Exarticu-lations

Frac ture s offacialbone plate

Fractures ofalveolarprocess

4 1

5 1

15 1

53 4

67 4

135 4

49 5

19 3

6 8

No. of involvedteeth

Maxil- Mandi-lary bularteeth teeth



2 050 0%

0 10% 100%

10 1

67% 100%40 074% 0%28 142% 25%66 149% 25%25 251% 40%

7 037% 0%

6 0100% 0%



3 075% 0%

0 00% 0%6 0

40% 0%12 222% 50%17 225% 50%28 021% 0%13 027 0%4 0

21% 0%

0 80% 100%

[njuries to the chin


2 050 0%

2 04070 0%

1 0

7 % 0%5 19 % 2 5 %3 05 % 0%8 16 % 2 5 %2 14% 20%0 00% 0

0 00 7 0

Fig . 2. Indirect trauma to the chin, transferred to the dental arches, has provoked crown-rootfractures of both maxillary right premolars by forceful occlusion.


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338 A N D R E ASEN

Ta b l e 12

R el a t i o n b e t w e e n h ar d a n d s o f t t i s s ue i n j u r i e s (p e r m a n e n t d e n t i t i o n )

Crownfractures

Crown-rootfractures

Root

fracturesSub-

luxations

Intrusiveluxations

Extrusiveluxations

Exarticu-lations

Fractu res offacialbone plate

Fractures ofalveolarprocess

No. of involvedteeth


319 38

56 7

68 21

159 46

39 1

320 95

178 18

63 22

79 51



17555%26467435

52%9660%1333%

208

11766%35567c

6987%

65 ~

1950%

114%5

248

17%1

100%3638%

950%1359%

2039%



Injurics to the chin


8527%1120%27

40%4328%1641 7 c

10433%6436%2133%

1013%

1950%

229%9

43%2044%

1

4446%

633%1255%

3365 ~

1WC/O

5 5 517% l3fh21 638% X6 ,

4 10

6% 48%,18 2011% 44%8 1

21% 100%42 3513% 377621 1012% 56%)12 919% 40%

20 1025% 20%

D i s c u s s i o n

Statistics concerning different types ofdental injuries may vary according totreatment institution. Thus a previousstudy dealing with the type of dentalinjuries treated by the Municipal SchoolDental Service in Copenhagen (Ravn GRossen 1969), differs significantly fromth e present hospital material, an d a com-parison between the two materials showsthat severe injuries, such as luxationsan d bone injuries, dominate in the hospi-tal material, in contrast to crown frac-tures. Apart from this discrepancy, pre-sumably due to the selection of the pre-sen t material, a num ber of clinical fac-tors are in accordance with previous in-vestigations. This applies for instance to

th e dom inance of males in th e sex ratio( A b r a h a m 1963, B u f f n e r1968, Edward &N o r d 1967, Ellis 1960, Eickenbaum 1963,Gelbier 1967, G r u n d b y 1959, Gaare,Hagen G Kansfad 1958, Hal l e f 1953,Hardwick G N e w m a n 1954, Parkin 1967,Ravn & Rossen 1969, Sundvall-Hagland1964, Wa l l e n f i n 1959) location of in-juries ( A b r a h a m 1963, D o w n 1957, Ellis1960, Gelbier 1967, G r u n d y 1959, Gaare,Hagen G Kansfad 1958, Hal lef 1953,Krefer 1967, N o r d 1966, 1968, Parkin1967, Ravn G Rossen 1969, Schutz-mannsky 1963, Ta a f z 1967, Wa l l e n f i n1959) as well as the high frequency ofrepeated traumas (Gelbier 1967, Hard-

wick G N e w m a n 1954, Ravn & Rossen1969, Sundvall-Hagland 1964).


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340 ANDREASEN

Previous studies have revealed thatdental injuries usually affect only a

single tooth G r u n d y 1959, Ravn & Ros-sen 1969, Schutzmannsky 1963). The pre-sent material showed an average of 2.3injured teeth per individual, a figurepossibly reflecting the more complicatedinjuries treated in th e hospital.

When comparing injuries affectingprimary and permanent teeth (Table 5 ) ,it appears that traumas in the primarydentition are usually confined to thetooth-supporting structures, i. e. luxa-

tions and exarticulations. Thi s is prob-ably related to th e resiliency of thealveolar bone in these age groups , favor-ing dislocations rather than fractures.Gro upi ng of denta l inju ries accordingto type of trauma yields many prob-lems due to the complex etiology. It hasbeen presumed that a number of factorsare responsible for the type of inflictedinjury, such as energy of impact, re-siliency? an d angle of t he impactingobject (Hallet 1953). Most of these fac-tors‘could not be estimated from therecords used in this study. However, thepresent grouping of injury origins pos-sibly reflects differences in energy ofimpact, f o rh t a n c e , Group 5 (fall dur-ing play) p(esumab1y represents a traumatype with less iinpact energy than Group6 and 8 (fall with a bicycle or motorvehicle and automobile accidents). Fur-

therm ore th e factor resilience of the im-pacting object may be responsible forthe different distribution of injurieswithin Group 7 and 9 (injuries duringfight and foreign bodies striking theteeth).

Th e energy of th e impact may be re-sponsible for the higher frequency ofbone fractures in Group 3 (fall on astaircase) as compared to Group 1 (fallduring play). When Group 5 (fall) and

Group 6 (fall with bicycle or motor

vehicle) and Group 8 (automobile acci-dent) are compared, in th e mentioned

order, the probable increase in energyof the tra uma impact seems to be fol-lowed by an increase in bone injurieswhile the frequency of tooth fracturesdecreases. In the latter group the highfrequency of chin injuries is probablyrelated to the collision between thedriver and the steering wheel or pas-sengers’ hitting the dashboard.

The marked difference in injury pat-tern between Group 7 and 9 is possiblyrelated to a difference in the resiliencyof the impacting object. Possibly theforces involved in fight injuries repre-sent a blu nt or padded impact where theforces hitting the tooth are transferredto th e periodontal structures, resultingin l uxations and alveolar fractures. Th ecounterpart to this type of traum a ispossibly an impact caused by a foreignbody’s hitt ing the oral structures (G rou p9). Most of these traumas represent ahard unelastic impact which tends totransmit the energy momentarily to alimited part of the crown area, thusfavoring a crown fracture.

The relationship between injuries tothe hard dental tissues and the support-ing structures, shown in Tables 11 and12, may to some extent be explained bycertain engineering principles. Frontalimpacts to the labial aspect of anteri or

teeth generate forces which tend to dis-place the tooth palatally. If the forcecauses a crown fracture, the greater partof the energy of the impact is expendedto create the fracture and is not trans-mitted to the root portion. This may ex-plain why crown or crown-root fracturesare seldom associated with dislocations.O n the ot her hand, if t he impact doesnot inflict a fracture, the energy is trans-ferred to the periodontal tissues and a

dislocation of th e tooth may occur, ac-


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ETIOLOGY AND PATHOGENESIS OF TRAUMATIC DENTAL I N JURIES 341

cording to the direction of the impact.I t appears from many case histories inthis stu dy and t he figures listed in Table10 that intrusions are the result of a di-rect impact hitting the incisal edge in anaxial direction. The tooth is therebyforced into the supporting bone and thefigures show that the energy of this im-pact, in contrast to other luxation in-juries, is al,so expende d to a fracture ofthe crown.

The location of the impact may deter-

mine the injury to the tooth and itssupporting structures. Thus, if the lipis hit first by t he tra uma, it may possiblyact as an impact absorber reducing thechance of fractur e and increasing th erisk of movement of the entire tooth.This may possibly explain the frequentassociation between lip injuries an d trau-matic lesions involving the supportingstructures, such as subluxations, extru-sive luxations, exarticulations, and frac-

tur es of t he alveolar process..Impacts may act directly or indirectly

upon the dental structures Benneff1963). Thus‘ dire ct rauma occurs when atooth is str uck against an object, e. g.playgrou nd, table, chair, or a fist, whereasan iniirect trauma is inflicted when themandi$ular dent al arch is forcefullyclosed. against th e maxilla, a s may re-sult from a blow on the chin in a fight.The latter type of injury favors crown-

root fractures especially in th e premolarand molar region. This is possibly theexplanation for the high frequency ofcrown-root fractures found related tochin injuries in this study.

Acknowledgments - This investigation wassupported by grants from the Danish StateResearch Foundation and the Danish DentalAssociation, “Fonden ti1 statte for viden-skabelige og praktiske undersagelser indenfortandlzgekunsten”. The statistical calculations

were performed by the Northern EuropeUniversity Computing Center.

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Address:J. 0 AndreasenDen tal DepartmentUniversity Ho spital (Rigshospifalet)9, BlegdamsveiDK-2100, Copenhagen, Denmark

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