Watts 2009.

Methods	Study design: 2‐arm parallel randomised trial Conducted in: USA Number of centres: 1 Setting: hospital Recruitment period: unclear Funding source: not reported
Participants	Inclusion criteria: 12 to 84 months, at least 1 extraction of a primary maxillary tooth, use of a clamp, and at least 1 maxillary tooth needing pulpotomy/crown Number of participants randomised/evaluated: total = 48 (group 1 = 24, group 2 = 24) Group 1: mean age (years) = 3.71 Group 2: mean age (years) = 4.03 25 males, 23 females
Interventions	Group 1: IFL 2% xylocaine with 1:100000 adrenaline Group 2: no LA
Outcomes	Heart rate, respiratory rate, end tidal carbon dioxide
Notes	Induction sevoflurane, maintained with isoflurane/nitrous oxide Co‐interventions: All participants received 1 mg/kg of Keterolac 30 minutes before end of case Declarations of interest: none reported There was a sample size calculation Results were reported separately for different dental procedures
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Quote: "...randomly assigned" Comment: The paper did not state the method of sequence generation
Allocation concealment (selection bias)	Unclear risk	There was insufficient information to make a judgement
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Quote: "The operators, anaesthesiologists and recorders were not blinded" Comment: The study blinded participants. Outcome assessment was considered to be "objective"; therefore; the study authors justified the lack of blinding of personnel
Blinding of outcome assessment (detection bias) All outcomes	High risk	Quote: "The operators, anaesthesiologists and recorders were not blinded" Comment: Outcome assessment was considered to be "objective"; therefore, the study authors justified the lack of blinding of outcome assessment
Incomplete outcome data (attrition bias) All outcomes	High risk	All participants were included in the analysis, but the study authors reported that "only 46 percent of the study data being complete collections per patient"
Selective reporting (reporting bias)	Low risk	The study recorded all expected outcomes
Other bias	Low risk	There was no other apparent bias.

ASA = American Society of Anesthesiology Classification; ASA I = normal, healthy patient; ASA II = patient with mild systemic disease / no functional limitation; CHEOPS = Children's Hospital of Eastern Ontario Pain Scale; ECG = electrocardiogram; EMLA = eutectic mixture of local anaesthetics; FLACC = Faces Legs Activity Crying Consolability; GA = general anaesthesia; IFL = immediate functional loading; ILA = intraoperative local anaesthesia; ITR = intraligamental injection; IV = intravenous; LA = local anaesthetic; MPDS = modified pain/discomfort scale; NLA = no local anaesthesia; PACU = post‐anesthesia care unit; SD = standard deviation; SEM = standard error of the mean; STPPPS = Simplified Toddler Preschooler‐Postoperative Pain Scale; TPPPS = Toddler Preschooler‐Postoperative Pain Scale; VAS = visual analogue scale.