A recent cross-correlation between the SDSS DR7 White Dwarf Catalog with the Wide-Field Infrared Survey Explorer ( WISE ) all-sky photometry at 3.4 , 4.6 , 12 , and 22 microns performed by Debes et al .
( 2011 ) resulted in the discovery of 52 candidate dusty white dwarfs ( WDs ) .
The 6 \arcsec WISE beam allows for the possibility that many of the excesses exhibited by these WDs may be due to contamination from a nearby source , however .
We present MMT + SWIRC J - and H -band imaging observations ( 0.5-1.5 \arcsec PSF ) of 16 of these candidate dusty WDs and confirm that four have spectral energy distributions ( SEDs ) consistent with a dusty disk and are not accompanied by a nearby source contaminant .
The remaining 12 WDs have contaminated WISE photometry and SEDs inconsistent with a dusty disk when the contaminating sources are not included in the photometry measurements .
We find the frequency of disks around single WDs in the WISE \cap SDSS sample to be 2.6-4.1 % .
One of the four new dusty WDs has a mass of 1.04 ~ { } M _ { \odot } ( progenitor mass 5.4 ~ { } M _ { \odot } ) and its discovery offers the first confirmation that massive WDs ( and their massive progenitor stars ) host planetary systems .