Journal of Clinical Periodomology 1983: 10: 443-451 Short Communication Key words: Denial cemenlum - developmenlul dulurbancf - Juvenile pcriodoniiiii - scanning elecirori microsciipy. Accepted for publication January 30, 19S3 Cementum hypoplasia in teeth affected by SVEN LlNDSKOG AND LHIF BLOMLOF Department of Oral Pathology, School of Dentistry, Karolinska Institute and Department of Periodontology, Skanstull, Stockholm, Sweden Abslraci. The cemental surface of teeth affected byjuveniJeperiodontitis was examined using scanning electron microscopy. Molars affected by chronic marginal periodontitis and healthy molars were included as controls. The entire mesial root of teeth affected by juvenile periodontitis showed extensive areas of cementum hypoplasia with exposed dentinal tubules. The hypoplasias were found also on the infracrestal part of the root indicating that they had not been caused by exposure to the oral environment or by any treatment. Csmentum hypoplasias were not found in any teeth from the control material. The impaired periodontal attachment in the faypoplasia may facilitate penetration by the special motile bacteria which have beenfoundinplaquefrom teeth with juvenile periodontitis. Based on the findings in the present study and the hereditary background of juvenile periodontitis it was suggested that development of the disease is initiated by a hereditary developmental disturbance of the cementum. Juvenile periodontitis is a periodontal disease which affects adolescent or young adult in- dividuals (Wannermann 1938, Baer 1971,Saxen 1980a, b). The disease has been shown to occur in two varieties - a generalized form, affecting ali permanent teeth and a localized form, located to only a few permanent teeth. The first visible sign of the localized form of juvenile periodotititis is a rapid loss of alveolar bone around the mesial root of one of the first pertnanent moiars or around the roots of the central incisors {Baer 1971). The disease affects progressively more of the permanent dentition. During recent years treatment with tetracycline and an intense oral hygiene have proved suc- cessful therapies (Lindhe 1982). The etiology and pathogenesis of juvenile periodontitis are not known. Heridity seems to be the factor which shows the strongest correla- tion to development of the disease (Saxen 1980a, c, Fretwell et a!. 1982). However, both bacteriological (Socransky 1970, Newman et al, 1974) and immunoiogical (Lehner et al. 1974) factors have been discussed. The composition of subgingival plaque from teeth with juvenile periodontitis differs from that of teeth with chronic marginal periodontitis (Slots 1976, Wes- tergaard et al. 1978, Liljenberg & Lindhe 1980). The bacteriological and immunoiogical findings do not, however, explain why the local variety of the disease initially affects only permanent first molars or central incisors. In 1923 Gottlieb described the disease now known as juvenile periodontitis as a "diffuse atrophy of the alveolar bone". He later suggested that it was caused by a defect in the dental cementum (Gottlieb 1928). In view of this suggestion of a local etiology we found it of interest to examine the surface of the cementum from teeth affected by juvenile periodontitis.
Department of Oral Pathology, School of Dentistry, Karolinska Institute and Department of Periodontology,Skanstull, Stockholm, Sweden
Abslraci. The cemental surface of teeth affected byjuveniJeperiodontitis was examined using scanningelectron microscopy. Molars affected by chronic marginal periodontitis and healthy molars wereincluded as controls. The entire mesial root of teeth affected by juvenile periodontitis showed extensiveareas of cementum hypoplasia with exposed dentinal tubules. The hypoplasias were found also on theinfracrestal part of the root indicating that they had not been caused by exposure to the oral environmentor by any treatment. Csmentum hypoplasias were not found in any teeth from the control material. Theimpaired periodontal attachment in the faypoplasia may facilitate penetration by the special motilebacteria which have beenfoundinplaquefrom teeth with juvenile periodontitis. Based on the findings inthe present study and the hereditary background of juvenile periodontitis it was suggested thatdevelopment of the disease is initiated by a hereditary developmental disturbance of the cementum.
Juvenile periodontitis is a periodontal diseasewhich affects adolescent or young adult in-dividuals (Wannermann 1938, Baer 1971,Saxen1980a, b). The disease has been shown to occurin two varieties - a generalized form, affectingali permanent teeth and a localized form,located to only a few permanent teeth. The firstvisible sign of the localized form of juvenileperiodotititis is a rapid loss of alveolar bonearound the mesial root of one of the firstpertnanent moiars or around the roots of thecentral incisors {Baer 1971). The disease affectsprogressively more of the permanent dentition.During recent years treatment with tetracyclineand an intense oral hygiene have proved suc-cessful therapies (Lindhe 1982).
The etiology and pathogenesis of juvenileperiodontitis are not known. Heridity seems tobe the factor which shows the strongest correla-tion to development of the disease (Saxen
1980a, c, Fretwell et a!. 1982). However, bothbacteriological (Socransky 1970, Newman et al,1974) and immunoiogical (Lehner et al. 1974)factors have been discussed. The compositionof subgingival plaque from teeth with juvenileperiodontitis differs from that of teeth withchronic marginal periodontitis (Slots 1976, Wes-tergaard et al. 1978, Liljenberg & Lindhe1980). The bacteriological and immunoiogicalfindings do not, however, explain why the localvariety of the disease initially affects onlypermanent first molars or central incisors.
In 1923 Gottlieb described the disease nowknown as juvenile periodontitis as a "diffuseatrophy of the alveolar bone". He latersuggested that it was caused by a defect in thedental cementum (Gottlieb 1928). In view ofthis suggestion of a local etiology we found it ofinterest to examine the surface of the cementumfrom teeth affected by juvenile periodontitis.
444 LINDSKOG AND BLOMLOF
Material and Methods
1 first molar from each of 4 patients, 16-24years of age, was examined using scanningelectroti microscopy. All 4 patietits sufferedfrom juvenile periodontitis according to thecriteria of Saxen (1980b). 1 permanent firstmolar from each of the patients was extractedon account of a complicated furcation involve-ment.
10 first molars from each of 10 patients withchronic marginal periodontitis and 3 firstmolars from 3 yotmg individuals with no sign ofperiodontal disease were studied as controlmaterial. The controls were obtained as autopsymaterial.
Immediately after extraction the teeth wereimmersed in a 10% solution of sodium hypo-
chlorite for 24 h in order to make the rootsurfaces anorganic. They were then dehydrated,critical point dried (Andersson 1951) and sput-ter coated with gold.
Results
The first sign of bone loss was seen around oneof the first permanent molars in all 4 patients{Table l,Figs. 1-4). From the time of the earliestavailable radiographs and onwards progres-sively more teeth had become periodontallyinvolved.
The scanning electron microscopic examina-tion showed distinct morphological differencesbetween cementum from the teeth affected byjuvenile periodontitis and cementum from bothof the control groups. The cemental surface of
Table 1. Summary of records and radiographic findings of the patients affected by juvenile periodontitis at thetime of earliest available radiographs and at present. Age in years, F^female, M = male
Zusammenfassung klinischer und rontgenografischer Befunde von Patienten mit juveniler Parodontitis; zumZeitpunkt des am weitesten zuriickliegenden. zur Verfiigung stehenden und des heutigen Rontgenbefundes. Alter inJahren. F—weiblich. M—mannlich
Resume des donnees et resultats des examens radiographiques chez les patients atteints de parodontite juvenile,a I'epoque oil ont ete prises les premieres radiographies existant (earliest available) et au moment present. Ageen ann^es. E=sujet feminin. M^sujet masculin
Patient
C N .
M.K.
T.E.
Sex
F
F
M
Earliest
Age
18
12
18
!9
available radiographsTeeth showing bone
loss
17, 16, 14,24. 26, 2737, 36, 35, 45, 46. 47
36
16, 26, 36, 46, 47
46
Age
24
16
22
24
Present statusTeeth showing bone
loss
Ail [eeth
16, 26,36,46
16, 26, 36, 35, 3432, 31,41,42,46,47
36,46
Extractedteeth
16
36
26
46
Eigs. 1^4. Earliest available intraoral radiographs of the extracted molars (A) and radiographs taken shortlybefore extraction (B). Figs. 1A & B show patient C.N., Figs. 2A & B patient K.G., Figs. 3 A & B patient M.K. andFigs. 4A & B patient T.E. Arrows indicate level of the alveolar crests on the mesial side of the roots.Die am weitesten zuriickliegenden. zur Verfiigung stehenden intraoralen Rontgenbilder der extrahierten Motaren(A) und Rontgenbilder kurz vor der Extraktion (B). Die Eig. IA & B stammen vom Patienten C.N.. die Eig. 2A & Bvom Patienten K. G.. die Eig. 3A & B vom Patienten M.K. und die Eig. 4A & B vom Patienten T.E. Die Pfeilebezeichnen die Hohe der Knochenleisie mesial der Wurzeln.
Les molaires extraites: premieres radiographies existant (A) et radiographies prises peu de temps avant lesextractions (B). Eig. lA & B: patient C.N., Eig. 2A & B: patient K. G., Eig. 3A & B: patient M.K. et Eig. 4A & B:patient T.E. Les fleches indiquent le niveau de la crete alveolaire du cote mesial des racines.
DENTAL CEMENTUM IN JUVENILE PERIODONTITIS 445
446 LINDSKOG AND BLOMLOF
DENTAL CEMENTUM IN JUVENILE PERIODONTITIS .44?
the teeth affected by juvenile periodontitis periodontitis (Fig. 8). The distal and palatal
showed extensive areas of cementum hypo- roots also showed cementum hypoplasia but to
plasia (Fig. 5). The surface of the hypoplastic a minor extent. Dental calculus was not visible
areas was coarse and lacked cementum with a in any of the teeth with juvenile periodontitis.
normal appearance (Fig. 6). Occasionally den- The suprabony part of the roots with chronic
tinal tubules in cross-section were found in the marginal periodontitis was covered by deposits
deep parts of the hypoplastic areas (Fig. 7). The of dental calculus. The calculus was seen as a
hypoplastic areas were seen on both the supra- fitie granular material (Fig. 9) surrounding
bony and intrabony cemental surface of the large calculus deposits which protruded from a
mesial root in ail of the examined molars. The smooth cementai surface (Fig. 10). The intra-
intraorai radiographs taken at the time of bony cementai surface had an appearance sim-
extraction were used to determine the approx- iiar to the one observed in the non-affected
imate location of the alveolar bone level pro- teeth. However, holes from dissolved Sharpey's
jected on the root surface. In the most apical fibers were not noted (Fig. II).
part of the roots, resorption cavities were found The cementai surface of the non-affected
in 2 of the 4 molars affected by juvenile control teeth showed a mosaic-like pattern with
Fig. 5. Cementai surface in an anorganic preparation from the mesial root of a first permanent molar affected byjuvenile periodontitis. Extensive areas (arrows) on the root surface lacked covering layer of cementum.
Die Zementoberflache eines anorganischen Prdparuies der mesialen Wurzel eines, von juveniler Parodontitisbefallenen, ersien bleibenden Moiaren. An ausgedehnten Regionen (Ffeile) der Wwzeloherflache fehlt die deckendeZementschichi, Messtrich= 100 /int.
La surface du cemeni dans une preparation anorganique provenant de la racine mesiale d'une Un motairepermanente aneinie de parodoniite juvenile, i^asles zones (voir fieches) oil la couche de eement est absente sur lasurface radicutaire. Longueur du irait= 100 fan.
Fig. 6. Detail from Fig. 5 showing part of a cementum hypoplasia (CH). The hypoplastic areas had a coarsesurface and were seen as depressions in the root surface. They were surrounded by cementum with an apparentlynormal morphology, Bar=IO/im.
AusschniU der Fig. 5, der einenTeil der Zeiiienlhypoplasie zeigl (CH). Die hypoplastischen Oberflachen waren raiih.erschienen als Einsenkungen der Wurzeloberfidche und waren von Zemenl mil offenbar normaler Morphologieumgeben. Messtrich = 10 /im.
Detail d'une pariie de la Fig. 5, avec une partie d'une hypopiasie du cement (CH). Les zones hypopiasiiques avaientune surfaee grossiere ei apparaissaieni commc des depressions a la .surface de la racine. Etles etaienl entourees d'uncement semblani avoir une morphologie normale. Longueur du trail= 10 fim.
Fig. 7. Denlinal tubule in the deep part of a cementum hypoplasia from a first permanent molar affected byjuvenile periodontitis. Peritubular dentin (PD) and intertubular dentin (ID). Bar— ! //m.Denliniubu/i in der Tiefe der Zementhypoplasie eines von juveniler Parodoniitis befallenen ersien Moiaren.Pcritubulares Dentin (PD) und intertubulares Dentin (ID). Messtrich~ 1 fim.
Canalicule deniinaire a la partie profonde d'une liypoplasie du cemeni dans une Itre molaire permanenle atleinte deparodoniite juvenile. Dentine pericanaliculaire (PD) ei dentine intercanaliculaire (ID). Longueur du trait — I /xm.
Fig. 8. Resorplion lacuna (RL) on the most apical part of the root surface of a first permanent moiar affected byjuvenile periodontitis. In an anorganic preparation the resorption lacuna had a smooth surface. Bar— iO /im.
lie.wrptionslakune (RL) an dem am weitesten apikal gelegenen Teil der Wurzeloberflache eines von juvenilerParodontitis befallenen ersten bleibenden Moiaren. In einem anorganisehen Prdparat war die Oberfldehe derResorptionslakune glalt. Messtrich —10 /im.
Lacune de resorplion (RL) a la partie la plus apicale de la surface radiculaire d'une hrc molaire permanente atteintede parodontite juvenile. En preparation anorganique, la lacune de resorption presentait une surface Hsse.
448 LINDSKOG AND BLOMLOF
DENTAL CEMENTUM IN JUVENILE PERIODONTITIS 449
grooves and occasional holes from dissolved previously and the observations made in the
Sharpey's fibers (Fig. 12). The cementum had a present study are in accordance with those
similar appearance ail over the root and was findings (Saglie et al. 1974, Friskopp & Ham-
continuous all over the root surface. marstrom 1980, Lindskog 1982).
The cementum hypoplasia was found all over
the root surface including the intraalveolarDiscussion . .j.,. • .• . t. . -.. ^ r i i ^
part . I hjs indicates that it was most likely true
The present study has demonstrated that the hypoplasia and not an artefact caused by any
teeth affected by juvenile periodontitis lacked crevicular bacteria or any treatment such as
cementum on part of their root surface. The scaling. The total lack of cementum as indicated
morphology of the root surface with cemental by exposed dentinal tubules on part of the root
hypoplasia differed markedly from that of surface in teeth affected by juvenile periodonti-
normal cementum and cementum of teeth with tis may be interpreted in two ways. Organic
chronic marginal periodontitis. The cementa! cementum matrix which failed to undergo min-
surfaces from such teeth have been described eralization had been deposited in the hypo-
fig. 9. Supracrestai root surface from a first permanent moiar with chronic marginal periodontitis. Dental
calculus appeared as fine granular deposits (arrows) on a smooth cemental surface. Bar— 10 ^m.
Cher der Knochenleisie liegende Wurzeloberjlache eines ersien bleibenden Molaren mi! chronischer marginaler
Surface radiculaire supra-crestale. sur une J he inolaire permanenre aiieinie deparodoniise marginale chronique. Dulartre dentaire se presenle sous forme de fins depois granuleux (voir fleches) sur une surface cemeiUaire lisse.Longueur du Irait^^ 10 ftm.
Fig. 10. Large deposit of dental calculus (DC) on the suprabony cemental surface of a first permanent molar withchronic marginal periodontitis. The calculus deposits were perforated by numerous hoies from dissolvedorganic material. Bar=iOO/(m.
Umfangreiche Zahnsieinansammlung (DC) auf ciner iiber der Knochenleisie gelegenen Zememoberflache eines
ersien bleibenden Molaren mil chronischer marginaler Farodoniiiis. Die Zahnsieinansammlungen waren von
zahtreichen Lochern perforieri, die durch aufgelosies organisches Material enlsianden sind. Messirich—100 fim.
Importanls depots de lartre dentaire (DC) sur la surface supra-osseiise du cemeni dune lere molaire permanente
alleinte de parodoniite marginale chronique. Les depots de tartre presentaient de nombreusesperforations dues a la
dissolution de la substance organique. Longueur du trait=}00 fim.
Fig. II, Intraalveolar cemental surface from a first molar with chronic marginal periodontitis. The surface wassmooth and had a mosaic-like appearance in an anorganic preparation. Bar= 10 fim.
Inlraalveolare Zemenioberjlaehe eines ersten Molaren mil chronischer marginaler Farodontitis. Die Oberflache
war glati und haite in einem anorganischen Prdparai ein mosaikahnliehes Aussehen. Messlrich= 10 /Am.
Surface cemenlaire intra-atveolaire dune len- molaire presentani une parodontite marginale chronique. La surface
i'taii lisse ei presentait un aspect en mosa'tque en preparaiion anorganique. Longueur du irait — W /im.
Fig. 12. The root surface of a first permanent molar without any signs of periodontai disease in an anorganicpreparation. The cemental surface had a mosaic-like appearance with grooves and occasional holes fromdissolved Sharpey's fibers (arrows). Bar— 10 fim.
Anorganisches Prdparat der Wurzelobcrfldche eines ersien bleibenden Molaren ohne Anzeichen parodonialerKrankheit. Die Zementoberfldchc sah mosaikdhnlich aus mil Unebenheiten und gelegendlichen Lochern vonaufgelosten Sharpey'schen Fasern siammend (Ffeile). Messtrich = 10 fim.
Surface radiculaire d'une hre molaire permanente ne presentant aucun signe de maladie parodontale, vue enpreparation anorganique. La surface du cement presenle un aspect en mosaique et quelques trous. dCls a ladissolution des fibres de Sharpey (voir fteches). Longueur du trait = 10 fim.
450 LINDSKOG AND BLOMLOF
plastic areas, or cementum matrix had never
been present on the root surface. In either case
the hypoplastic areas probably lacked peri-
odonta! attachment with Sharpey's fibers. The
impaired attachment of the teeth to the alveolar
bone may favor penetration by motile bacteria
such as Spirochetes and flagellated rods. These
microorganisms dominate plaque from teeth
with juvenile periodontitis (Slots 1976, Wester-
gaard et al. 1978, Liljenberg & Lindhe 1980).
The finding of cemental hypopiasia in teeth
with juvenile periodontitis may, thus, contrib-
ute to an explanation as to why the disease is
initially located to only a few teeth.
Juvenile periodontitis seems to have a family
tendency (Saxen 1980a, c, Fretwel! et al. 1982).
The incidence rate is low and similar to other
hereditary developmental disturbances of the
teeth such as amelogenesis imperfecta and
dentinogenesis imperfecta (Gorlin & Goldman
1970, Piodborg 1970, Sedano et al. 1977). A few
inherited disorders, e.g. hypophosphatasia,
have been described where cementum hypopia-
sia is found. Patients suffering from hypo-
phosphatasia also show widened periodontal
spaces and premature loss of teeth (Pindborg
1970, Sedano et al. 1977) due to lack of
cementum on the root surface of these teeth.
Widened periodontal spaces have been reported
in cases of juvenile periodontitis (Ghckman
1952). It is, thus, tempting to suggest that the
development of juvenile periodontitis is initiated
by a heriditary developmental disturbance of
the cementum.
Acknowledgement
This investigation was supported by the Swedish
Medical Research Council, Grants No. X06001-
03A and No. 6651-01.
wurde die Oberflache des Wurzelzementes mit Ra-sterelektronenmikroskopie untersucht. Die Kontroll-zahne dieser Studie waren Molaren mit chronischermarginaler Parodontitis, sowie gesunde Molaren. Anden mesialen Wurzeln der Zahne mit juveniler Paro-dontopathie wurden ausgedehnte hypoplastisch ver-anderte Zementregionen mit exponierten Dentintu-buli gesehen. Solche Hypoplasien wurden auch anden apika! der Knochenteiste gelegcnen Wurzelan-teilen gefunden und das bedeuiet, dass sie wederdurch Exposition in das orale Milieu iioch ais Folge-zustand einer Behandlung entstanden sein konnen.An den Zahnen des Kontrollmateriaies wurden inkeinem Fall Zementhypoplasien gel'unden. Es istdenkbar, dass das krankhaft veranderte parodontaieAttachment bei Zementhyperplasien die Penetrationeines speziellen beweglichcn Mikroorganismus er-leichtert, der in der Plaque von Zahnen mit juveniierParodontitis gefunden worden ist. Aufgrund derResultate dieser Studie und des erbliclien Hinter-grundes der juveniien Parodontopathic kann ange-nommen werden, dass die Entwicklung dieser Krank-heit durch eine hereditare Entwicklungsstorung desWurzelzementes eingeleitet wird.
Resume
Hypoplasies du cement dans les dents alleinies deparodoniite juvenileLa surface du cement de dents atteintes de parodon-tite juvenile a ete examinee en microscopie electro-nique a balayage. Des molaires atteintes de parodon-tite marginale chronique et des molaires saines ont enoutre servi de temoins. La totalite de !a racine mesialedes dents atteintes de parodontite juvenile presentaiide vastes zones d'hypoplasie du cement avec denuda-tion de canalicuies dentinaires. On a aussi constate ceshypoplasies sur la partie infra-crestale de la racine, cequi indiquait qu'eltes n'etaient dues ni a l'expositionau milieu buccal ni a un traitement. Dans aucune desdents temoins on n'a constate d'hypopiasie du ce-ment. II est possible que l'attache parodontaie com-promise au niveau des hypoplasies facilite ia penetra-tion des especes de bacteries mobiles qu'on a inises enevidence dans la plaque de dents atteintes de paro-doiitite juvenile. Les resultats de la pr^sente etude etI'aspect hereditaire de la parodontite juvenile sem-blent indiquer que le developpement de cette maladiese pioduit a !a suite d'une alteration hereditaire duprocessus de developpement du cement.
Zusammenfassung
Zemertthypoplasie an Zahnen, die von juveniler Paro-dontitis befallen sindBei von juveniler Parodontitis befallenen Zahnen
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Address:
Sven LindskogKaroiinska InstitutetSchool of DentistryDepartment of Oral PathologyBox 4064S'141 04 HuddingeSweden
