Changes in subgingival microflora after placement and removal of fixed orthodontic appliances

Abstract

Introduction The placement of fixed orthodontic appliances may lead to increased plaque accumulation and changes in subgingival microflora. Objective The aim of this study was to examine the changes in frequency of subgingival microflora that occur after placement and removal of fixed orthodontic appliance using polymerase chain reaction (PCR). Methods This study included 33 orthodontic patients, who were divided into two groups. Subgingival plaque samples were collected from the right upper incisor (U1) and right upper first molar (U6). In group A, the samples were taken three times: before placement appliance (T1), after one month (T2), and after 3 months (T3). In group B the samples were also taken three times: before appliance removal (T1), after one month (T2), and after three months (T3). PCR method was used to determine the presence of P. gingivalis, A. actinomycetemcomitans, T. forsythia, and P. intermedia. Results In group A the frequency of P. gingivalis showed statistically significant decrease at U1 (p=0.049) and U6 (p=0.008), from T1 to T2, and at U1 (p=0.048) from T1 to T3. In group B only the frequency of T. forsythia showed a statistically significant decrease, at U6 (T1 vs. T2, p=0.004; T1 vs. T3, p=0.0003). Regarding other analyzed bacteria, changes in the presence were noticed but no statistical significance was found. Conclusion Placement of fixed appliances may have an impact on subgingival microflora, but in the first months after the placement and removal of the appliance changes were not significant, probably due to good oral hygiene.

Uvod Postavka fiksnih ortodontskih aparata može dovesti do povećanog nagomilavanja plaka i promena u subgingivalnoj mikroflori. Cilj rada Cilj ovog rada bio je da se ispitaju promene subgingivalne mikroflore nakon postavke i uklanjanja fiksnih ortodontskih aparata primenom reakcije lančanog umnožavanja molekula DNK (engl. polymerase chain reaction - PCR). Metode rada Studija je obuhvatila 33 pacijenta koja su svrstana u dve grupe (A i B). Uzorci plaka su uzeti iz subgingivalnog prostora desnog gornjeg centralnog sekutića (U1) i desnog gornjeg prvog kutnjaka (U6). U grupi A uzorci su uzimani pre postavke fiksnog aparata (T1), mesec dana posle postavke (T2) i tri meseca od postavke (T3). U grupi B uzorci su uzimani pre uklanjanja aparata (T1), mesec dana posle uklanjanja (T2) i tri meseca nakon uklanjanja (T3). Primenom metode PCR analizirano je postojanje mikroorganizama: Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, Tannerella forsythia i Prevotella intermedia. Rezultati U grupi A učestalost P. gingivalis pokazala je statistički značajno smanjenje na oba zuba (U1: p=0,049; U6: p=0,008) u vremenskom intervalu od T1 do T2. Uočeno je i statistički značajno smanjenje zastupljenosti ove bakterije na zubu U1 u intervalu od T1 do T3 (p=0,048). U grupi B samo se učestalost T. forsythia statistički značajno smanjila na zubu U6 u intervalu od T1 do T2 (p=0,004) i od T1 do T3 (p=0,0003). Učestalosti ostalih bakterija u obe grupe ispitanika nisu pokazale statistički značajne promene. Zaključak Postavka fiksnih aparata može da utiče na sastav subgingivalne mikroflore, ali u prvim mesecima nakon postavke i uklanjanja aparata uglavnom nisu uočene statistički značajne promene, verovatno zbog dobre oralne higijene.