1.Evaluation of the effects of whitening mouth rinses combined with conventional tooth bleaching treatments
Jaqueline Costa FAVARO ; Omar GEHA ; Ricardo Danil GUIRALDO ; Murilo Baena LOPES ; Andreza Maria Fábio ARANHA ; Sandrine Bittencourt BERGER
Restorative Dentistry & Endodontics 2019;44(1):e6-
OBJECTIVES: The aim of the present study was to evaluate the effect of whitening mouth rinses alone and in combination with conventional whitening treatments on color, microhardness, and surface roughness changes in enamel specimens. MATERIALS AND METHODS: A total of 108 enamel specimens were collected from human third molars and divided into 9 groups (n = 12): 38% hydrogen peroxide (HP), 10% carbamide peroxide (CP), 38% HP + Listerine Whitening (LW), 10% CP + LW, 38% HP + Colgate Plax Whitening (CPW), 10% CP + CPW, LW, CPW, and the control group (CG). The initial color of the specimens was measured, followed by microhardness and roughness tests. Next, the samples were bleached, and their color, microhardness, and roughness were assessed. Data were analyzed through 2-way analysis of variance (ANOVA; microhardness and roughness) and 1-way ANOVA (color change), followed by the Tukey post hoc test. The Dunnett test was used to compare the roughness and microhardness data of the CG to those of the treated groups. RESULTS: Statistically significant color change was observed in all groups compared to the CG. All groups, except the LW group, showed statistically significant decreases in microhardness. Roughness showed a statistically significant increase after the treatments, except for the 38% HP group. CONCLUSIONS: Whitening mouth rinses led to a whitening effect when they were used after conventional treatments; however, this process caused major changes on the surface of the enamel specimens.
Dental Enamel
;
Humans
;
Hydrogen Peroxide
;
Molar, Third
;
Mouth
;
Tooth Bleaching Agents
;
Tooth Bleaching
;
Tooth
;
Urea
2.Effect of post space preparation drills on the incidence of root dentin defects
Thaíse Ayres BEZERRA ZULI ; Orlando Aguirre GUEDES ; Gislaine Figueiredo Zarza ARGUELLO GONÇALVES ; Aurélio Rosa da SILVA JÚNIOR ; Álvaro Henrique BORGES ; Andreza Maria FÁBIO ARANHA
Restorative Dentistry & Endodontics 2020;45(4):e53-
Objectives:
This study investigated the incidence of root dentin defects after the use of different post space preparation (PSP) drills.
Materials and Methods:
Seventy-two bovine incisors were selected and obtained 14-mmlong root sections. Twelve roots served as controls with no intervention (G1). The 60 root canals remaining were instrumented using the crown-down technique with the ProTaper Next system and obturated using the lateral condensation technique. Specimens were randomly distributed into 5 groups (n = 12) according to the operative steps performed: G2, root canal instrumentation and filling (I+F); G3, I+F and PSP with Gates-Glidden drills; G4, I+F and PSP with Largo-Peeso reamers; G5, I+F and PSP with Exacto drill; and G6, I+F and PSP with WhitePost drill. Roots were sectioned at 3, 6, 9, and 12 mm from the apex, and digital images were captured. The presence of root dentin defects was recorded. Data were analyzed by the χ2 test, with p < 0.05 considered to indicate statistical significance.
Results:
Root dentin defects were observed in 39.6% of the root sections. No defects were observed in G1. G5 had significantly more cracks and craze lines than G1, G2, and G3 (p < 0.05), and more fractures than G1, G2, G3, and G4 (p< 0.05). When all root sections were analyzed together, significantly more defects were observed at the 12-mm level than at the 3-mm level (p < 0.05).
Conclusions
PSP drills caused defects in the root dentin. Gates-Glidden drills caused fewer root defects than Largo-Peeso reamers and Exacto drills.
3.Effect of post space preparation drills on the incidence of root dentin defects
Thaíse Ayres BEZERRA ZULI ; Orlando Aguirre GUEDES ; Gislaine Figueiredo Zarza ARGUELLO GONÇALVES ; Aurélio Rosa da SILVA JÚNIOR ; Álvaro Henrique BORGES ; Andreza Maria FÁBIO ARANHA
Restorative Dentistry & Endodontics 2020;45(4):e53-
Objectives:
This study investigated the incidence of root dentin defects after the use of different post space preparation (PSP) drills.
Materials and Methods:
Seventy-two bovine incisors were selected and obtained 14-mmlong root sections. Twelve roots served as controls with no intervention (G1). The 60 root canals remaining were instrumented using the crown-down technique with the ProTaper Next system and obturated using the lateral condensation technique. Specimens were randomly distributed into 5 groups (n = 12) according to the operative steps performed: G2, root canal instrumentation and filling (I+F); G3, I+F and PSP with Gates-Glidden drills; G4, I+F and PSP with Largo-Peeso reamers; G5, I+F and PSP with Exacto drill; and G6, I+F and PSP with WhitePost drill. Roots were sectioned at 3, 6, 9, and 12 mm from the apex, and digital images were captured. The presence of root dentin defects was recorded. Data were analyzed by the χ2 test, with p < 0.05 considered to indicate statistical significance.
Results:
Root dentin defects were observed in 39.6% of the root sections. No defects were observed in G1. G5 had significantly more cracks and craze lines than G1, G2, and G3 (p < 0.05), and more fractures than G1, G2, G3, and G4 (p< 0.05). When all root sections were analyzed together, significantly more defects were observed at the 12-mm level than at the 3-mm level (p < 0.05).
Conclusions
PSP drills caused defects in the root dentin. Gates-Glidden drills caused fewer root defects than Largo-Peeso reamers and Exacto drills.