OBJECTIVE: The aim of this study was to compare subgingival irrigation with tetracycline hydrochloride (TTC-HCL) as adjunctive treatment to scaling and root planning (SRP) on induced periodontitis in rats. MATERIAL AND METHODS: In 60 rats, periodontal disease was ligature-induced at the mandibular left first molar. After 7 days, the ligature was removed and all animals were submitted to SRP, and divided into 2 groups according to the following treatment: C (n=30) - subgingival irrigation with 1 mL of saline; T (n=30) - subgingival irrigation with 1 mL of TTC-HCL (50 mg/mL). Ten animals in each group were euthanized at 7, 15 and 30 days posttreatment. The histometric values were statistically analyzed (p<0.05). RESULTS: In the histometric analysis, at 7, 15 and 30 days, Group T (0.72±0.05 mm², 0.57±0.14 mm², 0.62±0.07 mm²), showed less bone loss (p<0.05) than Group C (1.35±0.25 mm²; 1.40±0.31 mm²; 1.29±0.27 mm²), respectively. CONCLUSIONS: Subgingival irrigation with TTC-HCL was an effective adjunctive treatment for periodontal disease induced in rats.

OBJECTIVE: The aim of this study was to assess radiographically the effect of photodynamic therapy (PDT) as an adjunctive treatment to scaling and root planing (SRP) on induced periodontitis in dexamethasone-induced immunosuppressed rats. MATERIAL AND METHODS: The animals were divided into 2 groups: ND group (n=60): saline treatment; D group (n=60): dexamethasone treatment. In both ND and D groups, periodontal disease was induced by the placement of a ligature in the left first mandibular molar. After 7 days, ligature was removed and all animals received SRP, being divided according to the following treatments: SRP: saline and PDT: phenothiazinium dye (TBO) plus laser irradiation. Ten animals per treatment were killed at 7, 15 and 30 days. The distance between the cementoenamel junction and the height of the alveolar bone crest in the mesial surface of the mandibular left first molars was determined in millimeters in each radiograph. he radiographic values were analyzed statistically by ANOVA and Tukey's test at a p value <0.05. RESULTS: Intragroup radiographic assessment (ND and D groups) showed that there was statistically signifcant less bone loss in the animals treated with PDT in all experimental periods compared to those submitted to SRP. Intergroup radiographic analysis (ND and D groups) demonstrated that there was greater bone loss in the ND group treated with SRP compared to the D group treated with PDT at 7 and 30 days. CONCLUSION: PDT was an effective adjunctive treatment to SRP on induced periodontitis in dexamethasone-induced immunosuppressed rats.

Este estudo avaliou e comparou in vitro a ocorrência da infiltração marginal em restaurações adesivas, com a utilização de remoção mecânica e químico-mecânica do tecido cariado. Para a proposição, 40 dentes molares humanos extraídos cariados foram divididos em quatro grupos: GI (brocas + Prime & Bond NT + TPH), GII (Carisolv + Prime & Bond NT + TPH), GIII (brocas + SBMP + Z100) e GIV (Carisolv + SBMP + Z100). Após a execução das restaurações e termociclagem, os dentes foram expostos a corante, seccionados e avaliados qualitativamente. Os resultados demonstraram que o sistema de remoção de tecido cariado não influenciou a ocorrência de microinfiltração em quaisquer margens cavitárias. Nas margens dentinárias, a utilização do sistema restaurador Prime & Bond NT + TPH demonstrou menor ocorrência de microinfiltração do que o sistema SBMP + Z100.

This study carried out an in vitro evaluation and comparison of the occurrence of marginal leakage in bonded restorations using mechanical or chemical-mechanical (Carisolv) removal of carious tissue. For that purpose, 40 extracted decayed human molars were divided into 4 groups: GI (burs + Prime & Bond NT + TPH), GII (Carisolv + Prime & Bond NT + TPH), GIII (burs + SBMP + Z100) and GIV (Carisolv + SBMP + Z100). After accomplishment of the restorations and thermal cycling, the teeth were exposed to dye, sectioned and qualitatively evaluated. The results demonstrated that the system of removal of carious tissue did not influence the results of microleakage at any of the cavity margins. At dentinal margins, use of the Prime & Bond NT + TPH restorative system allowed the occurrence of less microleakage than the SBMP + Z100 system.