Inter are still superior and with the result they received in this match, they are still very comfortable with a 4 point difference from Juventus who are in second place. In addition, Lautaro also further distanced himself from the top scorer competition this season because with the 1 goal he scored in this match, he was away from the pursuit of other players in the top score.
Inter wasn't very superior in the match against Lazio but they could play more effective. Lazio played not very badly, they actually could give good challenge to Inter Milan. However, Inter Milan has a better quality of attackers, they sill could score 2 goals although the match was very tight. 4 point difference seems not very safe for Inter Milan, Juventus still has a big chance to overtake it. But winning the match brings positive impacts for Inter players, they will be more confident for the next matches.The difference of 6 points is now too much, especially when his rival is Sassuolo players Berrardi. But the good thing this season is that some of the top scoring candidates this season are dominated by Inter and Milan players 
Do you mean 6 goals differences?Berardi seems hard to overtake the first place (Martinez).
I'm very sure that Martinez will be the top scorer of Serie A this season.