Dutta 2016.

Study characteristics
Methods	Study design: parallel RCT Conducted in: India
Participants	Inclusion criteria Age 17 to 36 years People with a mandibular third molar indicated for extraction Exclusion criteria People with pericoronitis, periapical infection, or lesions with respect to impacted third molars Opposing traumatic occlusion or impinging upper third molars Smokers, alcoholics, and any systemic diseases Females on oral contraceptives Individuals with incomplete follow‐up were excluded from the study Number evaluated: 40 participants/40 teeth
Interventions	A randomised comparative prospective study of platelet‐rich plasma (PRP), platelet‐rich fibrin (PRF), and hydroxyapatite (HA) as a graft material for mandibular third molar extraction socket healing Participants were randomly distributed into 4 groups of 10 participants. Control: extraction socket closed without any graft material PRP‐treated group: extraction socket filled with PRP before closure of the sockets PRF‐treated group: extraction socket filled with PRF before closure of the socket HA‐treated group: extraction socket filled with HA before closure of the socket Extraction of mandibular third molars was done under local anaesthesia using the standard technique. A triangular flap using ward‐I or ward‐II incision or an envelope flap was raised.
Outcomes	Swelling: mean of 3 measurements Pain: VAS based on 6‐point facial Wong‐Baker Scale (cannot be used in data analysis due to lack of clarity) Dry socket: Blum's method Soft tissue healing Radiographic (IOPA) assessment
Notes	Sample size calculation: not reported
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Comment: the method of randomisation is not described
Allocation concealment (selection bias)	Unclear risk	Concealment methods are not described.
Blinding (performance bias and detection bias) patient	Unclear risk	Comment: the participants gave their consent to the procedure, but details are not provided as to how much information they were given. It is also unclear whether the participants in the control and HA groups also had their blood taken (if they were blinded to the group allocation, not having blood taken would indicate what remaining groups they were in).
Blinding (performance bias and detection bias) assessor	Unclear risk	Comment: it is unclear who measured the outcome variables
Incomplete outcome data (attrition bias) All outcomes	Low risk	No dropouts were mentioned.
Selective reporting (reporting bias)	Low risk	All planned outcomes were reported.
Other bias	High risk	Comment: there is a potential source of bias due to inconsistencies in the methodology, namely the surgical approach. The methods state "a triangular flap using Ward‐I or Ward‐II incision or an envelope flap was raised".