None directly, in the long term. His own proteges undid most of his reforms within a decade of his death.
So the background - Sulla had been Marius' second in command during the Jugurthine War and the war against the Cimbri et al. at the end of the 2nd century, and Marius partner in the war against the Allies at the beginning of the 1st. Marius was the military constant in the northern front; Sulla in the southern front - consuls and other magistrates having limited terms of office they were replaced every year if they didn't die.
Despite having a decent working relationship, the two generals came into conflict over which one would get the command against the Greek king Mithridates, who had taken advantage of Rome's crisis with the allies to seize the eastern provinces. There was some constitutional chicanery, the justice of which probably depends on your own political perspective. Sulla settled the matter by using the army he had commanded during the Social War to march on Rome, run Marius out of Europe, and get the proper legal arrangements made for his command in the East, where he spent the rest of the decade.
When Sulla returned to Italy in 83, he marched on Rome a second time to displace Marius' partisans who had taken control of the city while Sulla had been away (Marius himself had died in the meantime), and took it at the end of 82. He had himself appointed dictator legibus faciendis et reipublicae constituendae causa - for the purpose of making laws and situating the Republic. NB: This isn't a "dictator for life" thing despite the fact that there is no date of expiration of this office. This was appointing a dictator with an agenda (situating the Republic), and when the agenda was completed, in theory the office would expire naturally. Appian, BC 1.98, says Sulla asked for the position with no fixed term but a brief. He certainly didn't treat it like a "for life" appointment, resigning it in 81 and maintaining his position with just the consulship for 80, retiring and dying after holding that office for the usual year.
It was in the office of dictator that Sulla accomplished his reforms. I'm following Harriet Flower's reading of the reforms from her 2010 book. The traditional view is Gabba's; you can get that in the Cambridge Ancient History. That view is that Sulla didn't "reform" anything, but re-entrenched Rome's oligarchic government.
Sulla:
*doubled the size of the Senate, appointing enough to make up a full Senate of about 600, instead of the traditional ~300, at the beginning of the 70s very much degraded by civil war.
*increased the number of quaestors - the first elected office that gained a politician admission to the Senate - and praetors, and formalized the requirements for holding office, including age requirements and mandatory periods before repeating an office. populated the juries with senators (this is why he needed so many more senators - to fill juries)
*Flower says Sulla abolished the censorship and the princeps senatus- others might say the offices fell into disuse.
*completely neutered the tribunes of the Plebs. He removed their ability to propose legislation, hamstrung their veto, and barred anyone who held this position from further political office.
*standardized the roles of the various offices including provincial governors.
This drastically changed the nature of the Senate and of the competition for offices. Before, the Senate had been a deliberative and advisory body made up of former magistrates; now most members had no experience of office, might not be involved either in hearing or speaking in the Senate, and spend large chunks of time in juries. The new size of the Senate was maintained by electing 20(!) quaestors each year; the competition for consul became twice as stiff with 8 new praetors qualifying to run for consul every year.
Here's a quote about how this effected the people:
Ordinary people no longer heard political speeches (contiones) being made from the rostra in the Forum.... Nor could they vote in their own assemblies on legislation drafted by the tribunes of the plebs. In future they were simply called upon to ratify laws that had already been approved by the senate and that were proposed by the highest magistrates. They had lost much of their political presence and their occasions for civic expression....
Flower goes on to point out that the organizing principle of Sulla's government was law instead of custom and tradition; "in other words, lex was to replace mos maiorum." This is a hard break for her; this is Sulla throwing out some 700 years of government by consensus and custom.
Still, this is her verdict:
The innovative nature of Sulla's program can be gauged by the fact that it proved to be essentially unworkable.
People just did not stand for it. Flower notes attempts at repealing these reforms happened almost every year between 78 and 70, with significant programs of repeal winning in 75 and 70; 70 was the year Pompey and Crassus, Sulla's proteges, were consuls. They reinstituted the census, restored the tribunate, and reformulated the juries.
For Flower, Sulla was the last chance at government short of monarchy. The 30 odd years left until Augustus are governments of various strong men or cabals, having almost nothing in common with the Republican government of, say, the Second Punic War. The fact that Sulla's reforms could be undone demonstrates that they were not effective.
I mentioned I was relying heavily on Flower's The Roman Republics. Hers is I think the most recent take on Sulla's constitutional reforms. She's proposing a complete rewriting of the scheme we have of Roman history though; so approach with caution. On Sulla himself, Keavenney's biography, Sulla: The Last Republican, is I think still the last word almost 40 years after K. published it. K. is a complete apologist of Sulla, and makes him into something of a religious prophet. Again, for the orthodox view - that Sulla entrenched the nobility - see the CAH.