# SEM Studies Assessing the Efficacy of Laser Treatment for Primary Teetis: A Systematic Review
## 3 Results
### General Study Outcomes
\begin{table}
\begin{tabular}{c c c c} \hline \hline
**Reference Number** & **Laser Type** & **Investigation** & **Surface Characterization** \\ \hline \multirow{4}{*}{[PERSON] [21]} & Er:YAG & 48 human teeth & (dentin) \\  & Er:YAG & effect on dentin morphology, & When additionally using NaCl 5.25\%, \\  & 200 mJ, 10 Hz & shear bond strength of composite & the surface is smoother, there are more \\  & & resin to dentin & open dental tubules, and there is no \\ \hline \multirow{4}{*}{[PERSON] [22]} & Er:YAG & 80 human teeth (40 primary and 40 permanent) & Visible crater-like cavities with smooth \\  & Er:YAG & 40 permanent) & edges and a rough bottom \\  & 200 mJ, 10 Hz & thermal effects on the pulp & (dentine) \\  & & & No smear layer, open dental tubules \\ \hline \multirow{4}{*}{[PERSON] [23]} & Er:YAG & 120 human teeth & (enamel) \\  & 20 mJ, 10 Hz, 1.20 W & shear bond strength of composite & (dentine) \\  & & resin to dentin & Irregular surface, no smear layer, open \\  & & resin to dentin & dental tubules, no visible \\  & & & surface damage \\ \hline \multirow{4}{*}{[PERSON] [34]} & Er:YAG & 10 human teeth & (enamel) \\  & The laser parameters were & & In the laser-only group, there is an \\  & not described & effect on microhardness & irregular, rough, wrinkled surface with \\  & & & numerous cavitations and craters \\  & & & In the laser + fluorine group, a \\  & not described & effect on microhardness & homogeneous surface with small \\  & & & porosities and no cracks \\  & & & In the fluorine + laser group, a porous \\  & & & surface with numerous cracks \\ \hline \multirow{4}{*}{[PERSON] [24]} & Er:YAG & 21 human teeth & (dentin) \\  & 60 mJ/ 2 Hz (G2), & shear bond strength of composite & Uneven, peeling surface, craters and \\  & 80 mJ/2 Hz (G3), 100 mJ/2 Hz (G4) & & growees present, and areas where laser \\  & & resin to dentin & radiation did not reach \\ \hline \multirow{4}{*}{[PERSON] [25]} & Er:YAG & 48 human teeth & (enamel) \\  & Er:YAG & 48 human teeth & With parameters of 60 mJ/2 Hz, an uneven \\  & 60 mJ/2 Hz (G2), 80 mJ/2 Hz (G3), & 48 human bond strength of composite & Aux, without a specific etching pattern \\  & and 100 mJ/2 Hz (G4) & 48 near bond strength of composite & Aux, irregular surface, visible \\  & & resin to dentin & cracks, and small metal areas, no specific \\  & & & etching pattern \\  & & resin to dentin & With parameters of 100 mJ/2 Hz, \\  & & & anphractic surface with numerous gaps, \\  & & & without a specific etching pattern \\ \hline \multirow{4}{*}{[PERSON] [26]} & Er:YAG & 8 human teeth & (dentine) \\  & 10 Hz/200 mJ, 10 Hz/300 mJ and & & No smear layer in 3 cases. Saly, uneven \\  & 10 Hz/400 mJ & effect on dentin morphology & Aux, open dental tubules \\  & & & cracks and melting present only at \\  & & & parameters 400 mJ/10 Hz \\ \hline \multirow{4}{*}{[PERSON] [13]} & Er:YAG & 30 human teeth & (dentine) \\  & 300 mJ, 4 Hz & microleakage at cavities & No smear layer, exposed denntinal tubules, \\  & 300 mJ, 4 Hz & microleakage at cavities & micro irregularities, greater ablation of \\  & & & intertubular than pertubular dentin \\ \hline \multirow{4}{*}{[PERSON] [31]} & Er,Cr:YSGG & 40 human teeth & (enamel) \\  & 940 nm, 20-Hz; & 40 mechanaege at cavities & Visible cracks on the surface \\  & 2780 nm, 20-Hz, & & \\ \hline \multirow{4}{*}{[PERSON] [35]} & Nd:YAG & 39 human teeth & (dentine) \\  & 064 nm, 100 μs, 100 mJ, 15 Hz,1.5 W & effect on dentin morphology & \\ \hline \multirow{4}{*}{[PERSON] [36]} & Er:YAG & 240 specimens & (dentin) \\  & 2 W, 20 Hz power/cm \({}^{2}\), 100 mJ & shear bond strength of composite & Shear layer completely removed, denntinal tubules partially open \\ \cline{1-1}  & & resin to dentin & \\ \hline \end{tabular}
\end{table} 
Table 3: \(Cont.\)