Stainless steel crowns (to protect the nerve treatment)
Stainless steel crowns have been a very good choice to restore the primary teeth when the degradation have been severe.
The nickel chrome crown—commonly called the stainless steel crown—has proved to be the most successful restoration for large cavities in primary teeth.
3M ESPE Stainless steal Crowns offer long-term restorations of primary molars.
Actually there are some companies that are trying to make an aesthetic crown for primary posterior teeth.