Study: NCT01030666

Intervention type: DRUG
Group type: EXPERIMENTAL
Intervention: Doxycycline
Description: The patients of the doxycycline group will take 200 mg doxycycline once a day for 7 days after regenerative therapy of an infrabony defects.

Intervention type: DRUG
Group type: PLACEBO_COMPARATOR
Intervention: Placebo
Description: The patients of the doxycycline group will take 200 mg placebo once a day for 7 days after regenerative therapy of an infrabony defects.

Intervention type: PROCEDURE
Group type: EXPERIMENTAL
Intervention: modified/simplified papilla preservation flap; scaling
Description: Following an intra-crevicular incision a mucoperiosteal flap was reflected to a height of 5 mm exposing the bony margin of the defect and allowing complete visualization of the infrabony lesion. The flap was designed according to the modified or simplified papilla preservation technique to obtain primary closure of the wound and the membrane respectively. The flap was extended at least one tooth mesially and distally of the defect side. After complete removal of inflammatory granulation tissue, the root surfaces were thoroughly scaled and root planed.

Intervention type: PROCEDURE
Group type: PLACEBO_COMPARATOR
Intervention: modified/simplified papilla preservation flap; scaling
Description: Following an intra-crevicular incision a mucoperiosteal flap was reflected to a height of 5 mm exposing the bony margin of the defect and allowing complete visualization of the infrabony lesion. The flap was designed according to the modified or simplified papilla preservation technique to obtain primary closure of the wound and the membrane respectively. The flap was extended at least one tooth mesially and distally of the defect side. After complete removal of inflammatory granulation tissue, the root surfaces were thoroughly scaled and root planed.

Intervention type: BIOLOGICAL
Group type: EXPERIMENTAL
Intervention: Prefgel/Emdogain
Description: When using EMD the root surfaces facing the infrabony defect were conditioned with EDTA (prefgel; Institut Straumann AG, Basel, Switzerland) for 2 min. first. Then the EDTA was washed out with plenty of saline. After drying the surfaces EMD was applied starting at the bottom of the defect and proceeding coronally.

Intervention type: BIOLOGICAL
Group type: PLACEBO_COMPARATOR
Intervention: Prefgel/Emdogain
Description: When using EMD the root surfaces facing the infrabony defect were conditioned with EDTA (prefgel; Institut Straumann AG, Basel, Switzerland) for 2 min. first. Then the EDTA was washed out with plenty of saline. After drying the surfaces EMD was applied starting at the bottom of the defect and proceeding coronally.

Intervention type: DRUG
Group type: EXPERIMENTAL
Intervention: 0.12% chlorhexidine gluconate solution
Description: Furthermore, all patients were advised to rinse with a 0.12% chlorhexidine gluconate solution (ParoEx; Butler, Kriftel, Germany) for 2 min. twice daily for 5-7 weeksafter surgery.

Intervention type: DRUG
Group type: PLACEBO_COMPARATOR
Intervention: 0.12% chlorhexidine gluconate solution
Description: Furthermore, all patients were advised to rinse with a 0.12% chlorhexidine gluconate solution (ParoEx; Butler, Kriftel, Germany) for 2 min. twice daily for 5-7 weeksafter surgery.

Intervention type: DRUG
Group type: EXPERIMENTAL
Intervention: Ibuprofen 400 mg (if necessary)
Description: 400 mg ibuprofen qd was prescribed for patient's comfort if necessary.

Intervention type: DRUG
Group type: PLACEBO_COMPARATOR
Intervention: Ibuprofen 400 mg (if necessary)
Description: 400 mg ibuprofen qd was prescribed for patient's comfort if necessary.

Intervention type: DRUG
Group type: EXPERIMENTAL
Intervention: 1% chlorhexidine gluconate gel (if necessary)
Description: If soft tissue dehiscence was noted the patient was advised to use a 1% chlorhexidine gluconate gel (Chlorhexamed 1% Gel; GlaxoSmithKline, Bühl, Germany) twice daily

Intervention type: DRUG
Group type: PLACEBO_COMPARATOR
Intervention: 1% chlorhexidine gluconate gel (if necessary)
Description: If soft tissue dehiscence was noted the patient was advised to use a 1% chlorhexidine gluconate gel (Chlorhexamed 1% Gel; GlaxoSmithKline, Bühl, Germany) twice daily