A device for treating patients in need for tissue regeneration comprising: a guided regeneration membrane , said membrane comprising: a perforated region having several holes with a diameter of more than 30 microns; a first side region located at the left side of said perforated region and extending from a left edge of said membrane to a first folding line between said perforated region and said first side region ; and a second side region located at the right side of said perforated region and extending from a right edge of said membrane to a second folding line between said perforated region and said second side region ; wherein said first side region has no pores, or has pores such that the largest pore in said first side region has a diameter of up to 30 microns, wherein said first side region is configured to be folded along said first folding line so as to cover said perforated region , and wherein said second side region is configured to be folded along said second folding line so as to cover said first side region so said right edge of said membrane is adjacent to said first folding line, wherein said first and second side regions form, when folded, a soft tissue blocking region with two parallel layers covering at least a majority of said perforated region , said soft tissue blocking region has no pores or has pores such that the largest pore in said soft tissue blocking region has a diameter of up to 30 microns. a guided regeneration membrane , said membrane comprising: a perforated region having several holes with a diameter of more than 30 microns; a first side region located at the left side of said perforated region and extending from a left edge of said membrane to a first folding line between said perforated region and said first side region ; and a second side region located at the right side of said perforated region and extending from a right edge of said membrane to a second folding line between said perforated region and said second side region ; a first side region located at the left side of said perforated region and extending from a left edge of said membrane to a first folding line between said perforated region and said first side region ; and a second side region located at the right side of said perforated region and extending from a right edge of said membrane to a second folding line between said perforated region and said second side region ; wherein said first side region has no pores, or has pores such that the largest pore in said first side region has a diameter of up to 30 microns, wherein said first side region is configured to be folded along said first folding line so as to cover said perforated region , and wherein said second side region is configured to be folded along said second folding line so as to cover said first side region so said right edge of said membrane is adjacent to said first folding line, wherein said first and second side regions form, when folded, a soft tissue blocking region with two parallel layers covering at least a majority of said perforated region , said soft tissue blocking region has no pores or has pores such that the largest pore in said soft tissue blocking region has a diameter of up to 30 microns. <EOS>