Excerpt follows // Emphasis added // Source http://canlii.ca/t/gwvp6
 This is a motion brought by the defendant, Dr. Steven Mascarin c.o.b. as Family Dental Centre Inc. for leave to appeal the February 3, 2016 order of Tausendfreund J. dismissing the defendant’s motion for summary judgment.
 The story which gives rise to this action, as gleaned from the material filed by both parties and the decision of the motions judge dated February 3, 2016, includes the following information relevant to this motion for leave to appeal.
 The plaintiffs are husband and wife. On December 2, 2009, they attended the defendant’s dental clinic to inquire about possible tooth implants for the plaintiff, Amos Maracle. The defendant dentist examined Amos Maracle and recommended a procedure for either three or four implants. While still in the dentist’s chair, and with the assistance of his wife, Amos Maracle agreed on a plan for three implants.
 To his surprise, Dr. Mascarin then told Amos Maracle that he would start the procedure that very day.
 Amos Maracle had undergone heart surgery in 2007 and had been treated in 2008 for heart infection. His family physician and his heart specialist, Dr. Campbell, had advised him that it was necessary for him to have antibiotics before undergoing any medical or dental procedure. He was given a prescription for antibiotics and told to take the medication before a scheduled dental appointment.
 The defendant brought the motion for summary judgment heard on January 13, 2016. In support of that motion, the defendant tendered affidavits, in compliance of Rule 53.03 from Dr. Nicolucci on November 2, 2012 and Dr. Zoutman on March 6, 2013.
 These reports of Dr. Nicolucci and Dr. Zoutman state that they are based on their respective reviews of a copy of the defendant dentist’s clinical notes and records. In December of 2015, the Royal College of Dental Surgeons of Ontario advised counsel for the plaintiffs that:
(a) The College requested the original clinical chart from the defendant dentist to assist with its investigation of the complaint which the plaintiff, Amos Maracle, had made to the College, and
(b) The defendant advised the College that his original chart seemed to have gone astray and could not be located.
(a) The amount and type of antibiotic given to Amos Maracle and the length of time the dentist waited before starting the procedure are critical for the causation opinions. That is particularly so, the plaintiffs state, as the defendant asserts that he waited one hour while the plaintiffs’ evidence is that it was but 20 minutes between the time the antibiotics were administered and the procedure started.
 The plaintiffs also note that the discipline record of the defendant dentist with the Royal College of Dental Surgeons of Ontario indicates that in 2005 he had been found guilty for failing to keep records as required by the Regulations of the College and that he was found guilty of falsifying a record.
 On September 24, 2015, a medical-legal report was obtained from an endodontist, Dr. George Just. That report is attached as Exhibit “B” to the affidavit of Lorraine Thomson, sworn January 5, 2016. In that report, Dr. Just concluded that the defendant had breached the standard of care owed to Amos Maracle in that he:
(a) failed to confer with Mr. Maracle’s physician prior to performing a surgical procedure on Mr. Maracle despite his knowledge of Mr. Maracle’s cardiac condition;
(b) failed to have Mr. Maracle rinse with an antibacterial rinse prior to performing implant surgery in order to lower the bacterial blood which is vital in preventing bacterial endocarditis; and
(c) failed to adequately pre-medicate Mr. Maracle 30 minutes to an hour prior to his surgical implant treatment in contravention of the American Heart Association Guidelines.
 Furthermore, Dr. Just comments on the deficiencies he identified in the defendant’s expert reports. First, he took issue with Dr. Blake Nicolucci’s report as it was prepared on the basis that the antibiotics were administered an hour before surgery. The timing issue of Mr. Maracle’s pre-medication was therefore not considered.
 Second, Dr. Just found the opinion of Dr. Zoutman highly speculative. Dr. Zoutman opined that, in administering 2000 mg of amoxicillin, a blood level of 5-6 ug/ml was likely achieved in Mr. Maracle within 20 minutes. In arriving at this opinion, Dr. Zoutman failed to take into account that individuals absorb oral antibiotics at different rates depending on their stomach contents and individual physiology. He states that it is for this reason the American Heart Association Guidelines recommend an hour or at a minimum 30 minutes to account for individual absorption rates. The only way that Dr. Zoutman could prove an adequate level of amoxicillin in Mr. Maracle’s blood in 20 minutes or less would have been by performing a blood draw. However, a blood draw was not done.
 The defendant brought a motion for summary judgment arguing there was no genuine issue requiring a trial as the plaintiffs had failed to provide any admissible expert evidence to establish causation.
 I note that the records, notes and opinions of Dr. Campbell were served by the plaintiffs in October 2013, as attached to the affidavit of the plaintiff Maracle sworn October 8, 2013. They were further served in August of 2015 as attached to the affidavit of Lorraine Thomson sworn August 12, 2015 and further in January 2016 as attached to affidavit of Ms. Thomson of January 5, 2016. Had the defendant been so inclined, he could have sought to examine Dr. Campbell under Rule 39.03 as a witness before the hearing of a pending motion. That had been so as of October 2013. I have no evidence of any requests the defendant may have made in that regard on this motion.
 I also note that the records and notes of Dr. Campbell are admissible as business records made in the usual and ordinary course of a business under s. 35 of the Evidence Act and under s. 52 of that Act as a report obtained by a party to an action signed by a physician and with leave of the Court.
 For reasons stated, I find that the notes, records and opinion of Dr. Campbell are admissible. Accordingly, I am faced on this Summary Judgment motion with two competing sets of medical opinions on the issue of causation. That leads me to comments made by the Ontario Court of Appeal in Rothwell v. Raes, 1990 CanLII 6610 (ON CA),  O.J. No. 2298. Before the court was the issue of causation raised by the appellants who sought to have the court reverse specific findings of fact made by the trial judge in the decision under appeal. The court’s response at para 6 was this:
The question of causation is essentially a question of fact to be determined by the trial judge. It is not for this court to weigh conflicting evidence or to reassess the relative merits of contradictory expert testimony.
These comments on a parallel basis, in my view, apply here on this Summary Judgment motion which turns on the question of causation.
 In submissions, counsel for the defendant argues that the motions judge erred by not referring to paragraph 63 of Westerhof v. Gee Estate. For context, I will also quote paragraph 64 of the decision:
 If participant experts or non-party experts also proffer opinion evidence extending beyond the limits I have described, they must comply with Rule 53.03 with respect to the portion of their opinions extending beyond those limits.
 As with all evidence, and especially all opinion evidence, the court retains its gatekeeper function in relation to opinion evidence from participant experts and non-party experts. In exercising that function, a court could, if the evidence did not meet the test for admissibility, exclude all or part of the opinion evidence of a participant expert or non-party expert or rule that all or part of such evidence is not admissible for the truth of its contents. The court could also require that the participant expert or non-party expert comply with rule 53.03 if the participant or non-party expert’s opinion went beyond the scope of an opinion formed in the course of treatment or observation for purposes other than the litigation. [page 735]
 I do not see how the Court of Appeal leaves any ambiguity about this issue, specifically in their statements from paragraphs 76, 81 and 82 of their decision, as quoted by the motions judge at paragraph 34 of his ruling. The ruling of the motions judge at paragraphs 35 through 40 clearly identifies and answers the issues by applying the principles of law stated in the Westerhof case to the facts in this case. The issues identified in paragraphs 63 and 64 do not apply to Dr. Campbell’s report herein.
Leave to appeal shall not be granted unless,
a. there is a conflicting decision by another judge or court in Ontario or elsewhere on the matter involved in the proposed appeal and it is, in the opinion of the judge hearing the motion, desirable that leave to appeal be granted; or
b. there appears to the judge hearing the motion good reason to doubt the correctness of the order in question and the proposed appeal involves matters of such importance that, in his or her opinion, leave to appeal should be granted.
 I find that the defendant has failed to demonstrate that there is a conflicting decision by another court in Ontario since Westerhof v. Gee Estate, or elsewhere on the matter involved in the proposed appeal that in my opinion would make it desirable that leave to appeal be granted. I find that the Ontario Court of Appeal’s decision in 2015 by Westerhof stands as the defining authority regarding the use of participant expert opinions.
 The defendant has also failed to demonstrate that there appears to be good reason to doubt the correctness of the order in question and that the proposed appeal involves matters of such importance that in my opinion leave to appeal should be granted. The motions judge quoted and relied upon the relevant portions of the Westerhof v. Gee Estate decision, which give clear direction as to the distinction between a participant expert and an expert hired exclusively for the purpose of giving an opinion in the litigation.
 It is somewhat ironic that the process of a motion for summary judgment, which is intended to be a relatively summary process to increase access to justice, was first returnable in October 2013 and together with this motion, has consumed somewhere between 1500 to 1800 pages of written material seriously challenging the capacity of what is normally referred to as a “banker’s” box for holding the file. The oral submissions on this motion took approximately three hours. The process is becoming part of the problem in this case, rather than the solution.
|Citation:||Maracle v Dr. Mascarin c.o.b. as Family Dental Centre Inc., 2016 ONSC 271 (CanLII), <http://canlii.ca/t/gwvp6>, retrieved on 2017-01-14|