Usually post ERCP pancreatitis is an expected event which occurs very frequently but has a very short duration and no consequence. In case of difficult CBD cannulation, it is possible that the event may be amplified, but I do not know if pancreatic stenting is an effective option and how widely it is used and/or indicated in a subject with biliary obsruction. It depends, in other words, also by the primary indication to ERCP.

Sphincterotomy both biliary and pancreatic carry around 2 - 5% risk of causing pancreatitis. There is good meta-analysis data to support PD stenting in high risk cases such as sphincter of Oddi dysfunction or ampullectomy. Similarly, rectal diclofenac or indomethacin have the same effect. If you are having to perform a pancreatic sphincterotomy then it is likely to be a high risk case and therefore there would be some benefit expected.

The problem with post-ERCP pancreatitis is precisely the opposite of what Dr Ieradi Enzo states - in other words, it is the unpredictable cases of pancreatitis, when only a stent removal has taken place, for example, which cause the real problems, and, though most cases are relatively trivial, post-ERCP pancreatitis can be serious and even fatal, as is well-known. 

In fact, I find that the cases in which one is doing therapeutic pancreatic sphincterotomy are no more likely to get pancreatitis than other, simpler cases.  But I cannot see why you would be wanting to perform a pancreatic sphincterotomy in a case of failed biliary cannulation.  We need to know a bit more about the case to answer more accurately.

The most frequently described risk factors for post ERCP pancreatitis (PEP) are:

• suspected sphincter of Oddi dysfunction

• female gender

• previous pancreatitis

• precut sphincterotomy

• pancreatic contrast injection

(Endoscopy. 2003; 35(10):830-4. Risk factors for pancreatitis following endoscopic retrograde cholangiopancreatography: a meta-analysis)

A systematic review published in 2014 described the overall PEP incidence was 9.7%. Severity of PEP was 5.7% mild, 2.6% moderate and 0.5% severe. The incidence of PEP in high-risk patients was 14.7% and the severity of PEP was mild, moderate, and severe in 8.6%, 3.9%, and 0.8%, respectively, with a 0.2% mortality rate.

(Gastrointest Endosc. 2014. Incidence, severity, and mortality of post-ERCP pancreatitis: a systematic review by using randomized, controlled trials)

The main recommendations of European Society of Gastrointestinal Endoscopy for PEP prophylaxis are:

• routine rectal administration of 100 mg of diclofenac or indomethacin immediately before or after ERCP in all patients without contraindication.

• In addition to this, in the case of high risk for post-ERCP pancreatitis, the placement of a 5-Fr prophylactic pancreatic stent should be strongly considered.

• keep the number of cannulation attempts as low as possible.

• needle-knife fistulotomy should be the preferred precut technique in patients with a bile duct dilated down to the papilla. Conventional precut and transpancreatic sphincterotomy present similar success and complication rates; if conventional precut is selected and pancreatic cannulation is easily obtained, ESGE suggests attempting to place a small-diameter (3-Fr or 5-Fr) pancreatic stent to guide the cut and leaving the pancreatic stent in place at the end of ERCP for a minimum of 12 - 24 hours.

(Endoscopy. 2014 Sep;46(9):799-815. Prophylaxis of post-ERCP pancreatitis: European Society of Gastrointestinal Endoscopy Guideline)

You can also just leave a wire in the pd while you use a second cannula and wire to approach the bile duct, the wire having straightened out the 'kink' in the low cbd/common channel.  You may choose to use this wire to place a pancreatic stent at the end of the procedure, depending on the pancreatitis risks of the patient and the procedure up to that point.  I entirely agree with the rest of Dr Meine's answer, though the risk of pancreatitis in this country is significantly lower than 9.7%. (Williams EJ, Taylor S, Fairclough P et al, Gut 2007;56:821-9)