Study Year of
publication 		Number of patients Country Number of patients Titanium groups Roughness measurement Experimental time/biofilm analysis/microorganisms Main findings
Smooth surface Rough surfaces
Al Ahmad et al. [24] 2010 20 Germany 20 Ti-m: 0.0544 μm TiUnite® (electrochemical anodization): 0.544 μm (minimally rough) Atomic force microscope in a contact mode of
50 x 50 μm2 		3 days;
biofilm thickness and composition analyzed through fluorescence in situ hybridization and confocal laser scanning microscopy;
Eubacteria, Veillonella spp., Fusobacterium nucleatun, Actinomyces naeslundii, Streptococcus spp. 		Neither biofilm thickness nor composition showed statistical difference among smooth and minimally rough titanium surfaces (P > 0.05)
de Freitas et al. [25] 2011 6 Brazil 6 Ti-m: 0.47 μm Ti-Bl: 1 μm (minimally rough);
Ti-HA: 1.27 μm (moderately rough) 		Mechanical profilometer 1 and 3 days;
biofilm composition: microbiological identification test Checkerboard DNA-DNA hybridization; 24 species (ref Sokranski) 		It was not observed statistical significant differences for any species, in relation to the surfaces in the evaluated times (P > 0.05)
Giordano et al. [26] 2011 8 Italy 8 A) Ti-m: 0.306 μm;
B) Ti anodized at
V = 90 V: 0.309 μm;
C) Ti anodized at
V = 130 V: 0.355 μm;
D) Ti-6Al-4V: 0.342 μm;
E) Ti-6Al-4V anodized
at V = 100 V: 0.436 μm 		F) Ti-6Al-4V anodized at V = 120: 0.506 μm Single measurement done on a 1.25 x 1.75 mm area attained using a three-dimensional laser profilometer 1 day;
bacteria density: SEM observation of randomly selected areas (employment of scores 1 - less bacteria, 2 and 3 - more bacteria) 		The minimally rough group
(Ti-6Al-4V anodized at
V = 120) showed the worse contamination, characterized by thicker biofilm formation, when compared to smoother surfaces (P < 0.05)
Zaugg et al. [27] 2016 16 Switzerland 16 A) Ti-m: 0.093 μm;
B) ModMa: 0.287 μm;
C) TAV MG: 0.128 μm 		D) modSLA:
0.896 μm (minimally rough) 		Images were acquired using a confocal microscope and surface roughness was determined using objective lens 1 day;
biofilm formation: safranin staining assay, isothermal microcalorimetry, and SEM 		The minimally rough modSLA surface, but also the smooth surface ModMA showed greater biofilm formation than other smoother surfaces
(P < 0.05)
Hermann et al. [28] 2020 14 Germany 14 A) Ti-m: 0.18 μm;
B) Ti-6Al-4V: 0.16 μm 		A) Ti-p: 1.87 μm Profilometric analysis, made in triplicate for each group 3 days;
detection and absolute quantification of total bacteria (real-time quantitative polymerase chain reaction);
biofilm composition (DNA microarray) 		No statistical differences were observed on bacteria quantification between groups (P > 0.05). 16 bacteria species were identified on titanium specimens and no differences among groups was detached

Ti-m = machined titanium; Ti-Bl = titanium blasted with aluminum oxide particles; Ti-HA = titanium coated with hydroxyapatite; SEM = scanning electron microscopy; ModMa = machined and acid-etched TiZr alloy; TAV MG = machined titanium aluminum vanadium alloy with micro-grooves; modSLA = machined, sandblasted and acid-etched TiZr alloy; Ti-p = pure sand-blasted acid-etched titanium.