PMID- 18221295
OWN - NLM
STAT- MEDLINE
DCOM- 20081118
LR  - 20081022
IS  - 1600-0765 (Electronic)
IS  - 0022-3484 (Linking)
VI  - 43
IP  - 4
DP  - 2008 Aug
TI  - Cell death and quantitative reduction of rests of Malassez according to age.
PG  - 478-81
LID - 10.1111/j.1600-0765.2007.01050.x [doi]
AB  - BACKGROUND AND OBJECTIVE: Rests of Malassez are clusters of epithelial cells that 
      remain in the periodontal ligament throughout life. However, it has been reported 
      that the number of these structures decreases with age, and some epithelial cells 
      undergo apoptosis in rests of Malassez of young and adult rats. Therefore, the 
      purpose of the present study was to investigate the incidence of epithelial cell 
      death and the quantitative changes in the rests of Malassez in rat molars of 
      different ages. MATERIAL AND METHODS: Fragments containing the upper molars of 
      rats aged 29, 45 and 120 d were fixed, decalcified and embedded for analysis by 
      light microscopy. In the sections stained by hematoxylin and eosin, the number of 
      rests of Malassez and the number of nuclei of these epithelial structures were 
      obtained. Moreover, the nuclei exhibiting typical features of cell death were 
      also counted in each rest of Malassez. The terminal deoxynucleotidyl 
      transferase-mediated dUTP nick end labeling (TUNEL) method for detection of cell 
      death was also carried out. RESULTS: In all groups examined, some rests of 
      Malassez exhibited epithelial cell nuclei with typical features of apoptosis and 
      some of them were also TUNEL positive. From 29 to 120 d of age in rats, the 
      quantitative analysis showed a significant decrease in the total number of rests 
      of Malassez in the cervical, middle and furcation regions of the periodontal 
      ligament. Moreover, a significant decrease of epithelial cell nuclei was 
      concomitant to an increase in the frequency of cell death in the oldest rats. 
      CONCLUSION: These results suggest that epithelial cell death by apoptosis may be, 
      at least in part, responsible for the reduction in the number of rests of 
      Malassez according to age.
FAU - Goncalves, J S
AU  - Goncalves JS
AD  - Department of Morphology, Laboratory of Histology and Embryology, Dental School, 
      Sao Paulo State University (UNESP), Araraquara, SP, Brazil.
FAU - Sasso-Cerri, E
AU  - Sasso-Cerri E
FAU - Cerri, P S
AU  - Cerri PS
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - United States
TA  - J Periodontal Res
JT  - Journal of periodontal research
JID - 0055107
RN  - 0 (Chromatin)
SB  - IM
MH  - Aging/*pathology
MH  - Animals
MH  - Apoptosis
MH  - Cell Count
MH  - Cell Death
MH  - Cell Nucleus/ultrastructure
MH  - Chromatin/ultrastructure
MH  - Epithelial Cells/pathology
MH  - In Situ Nick-End Labeling
MH  - Male
MH  - Microscopy, Electron, Transmission
MH  - Periodontal Ligament/*pathology
MH  - Rats
MH  - Rats, Sprague-Dawley
EDAT- 2008/01/29 09:00
MHDA- 2008/11/19 09:00
CRDT- 2008/01/29 09:00
PHST- 2008/01/29 09:00 [pubmed]
PHST- 2008/11/19 09:00 [medline]
PHST- 2008/01/29 09:00 [entrez]
AID - JRE1050 [pii]
AID - 10.1111/j.1600-0765.2007.01050.x [doi]
PST - ppublish
SO  - J Periodontal Res. 2008 Aug;43(4):478-81. doi: 10.1111/j.1600-0765.2007.01050.x.