Uticaj pozicije demarkacije preparacije zuba na inflamaciju gingive i promenu sastava oralne mikrobne flore
Докторанд
Jovanović, MarijaМентор
Kostić, MilenaЧланови комисије
Kesić, LjiljanaKocić, Branislava
Milašin, Jelena
Đorđević, Nadica
Метаподаци
Приказ свих података о дисертацијиСажетак
The research started from the assumption that the tooth preparation for
a Porcelain-Fused-to-Metal (PFM) crowns with the chamfer finish line
position can cause damage to the surrounding periodontal tissue and a
change of the oral microbial flora composition. The aim of the study
was to examine the clinical parameters of inflammation (gingival index
and gingival bleeding index), cytomorphometric changes of the
gingiva, biochemical parameters of inflammation (interleukin 1β (IL-
1β), vascular endothelial growth factor (VEGF), matrix metalloproteinase
9 (MMP-9) and the presence of periodontopathogens (Porphyromonas
gingivalis, Aggregatibacter actinomycetemcomitans, Tannerella
forsythia, Prevotella intermedia) in the gingival crevicular fluid, as
well as the saliva microbiological composition before and after tooth
preparation and the composition of bioaerosols during the tooth
preparation with the chamfer finish line localized subgingivally and
equigingivally. The subjects were divided in...to two groups depending
of the finish line position of the tooth preparation (subgingival and
equigingival). The results of the study showed tooth preparation leads
to an increase in the gingival index and gingival bleeding index in both
experimental groups, with higher values presenting at subgingival
finish line position. The examined values of the concentration of the
biochemical inflammatory markers IL-1β and VEGF increased
significantly immediately after tooth preparation, and gradually
decreased during the observation period, while there was a decrease in
the MMP-9 concentration. The changes of concentration values of the
biochemical parameters depended on the finish line position with
greater statistical significance at the subgingival position of the tooth
preparation compared to the equigingival. Tooth preparation led to
changes in all cytomorphometric parameters, which indicate gingival
inflammation, with a greater effect caused by the subgingival finish line
position. The exposure of periodontopathogens is statistically significantly
higher in the intervals after tooth preparation, which indicates the
inflammatory potential of the prosthodontic procedure, with a higher
bacteria presence at the subgingival compared to the equigingival position
during the entire examination period. As the distance from the working
field (patients’ oral cavity) increased, the number of bacterial colonies
decreased proportionally in both examined groups. Qualitatively, the most
represented aerobic colonies were Staphylococcus epidermidis, Neisseria
spp, Streptococcus intermedius, while the most represented facultatively
anaerobic bacterial colonies were Haemophilus parainfluanzae and
Streptococcus sanguinis in both examined groups. The qualitative
microbiological composition of the oral cavity is correlated with the presence of colonies originating from bioaerosols. The quantitative
representation of aerobic and facultatively anaerobic microorganisms
in the oral cavity immediately after tooth preparation was lower in both
examined groups with an increase in aerobic and a decrease in
facultatively anaerobic colonies during the observation period. The
study results indicate a reversible gingival tissue inflammation caused
by tooth preparation with a greater changes in the subgingival finish
line position. The reversibility of the resulting changes indicates a low
possibility of permanent periodontal tissue damage caused by daily
prosthodontic procedure. Choosing the appropriate clinical procedure
prevents the development of periodontal diseases, reduces the possibility
of iatrogenic damage that can threaten the therapeutic effect, and
ensures the longevity of fixed prosthodontic restorations.