Randy Scott, et al., Appellants, v. Ogden Newspapers, Inc., d/b/a The Fairmont Sentinel, Respondent.

 STATE OF MINNESOTA
 IN COURT OF APPEALS
 C8-99-891

Jeffery L. Palmer, et al.,
Appellants,

vs.

John C. Erlandson,
Respondent.

 Filed December 27, 1999
 Affirmed
 Peterson, Judge

Wright County District Court
File No. C9980662

Alf E. Sivertson, Michelle M. Barrette, Sivertson & Barrette, P.A., The Barrister Building, 1465 Arcade Street, St. Paul, MN 55106-1723 (for appellants)

Bruce Jones, Martin N. Burke, Faegre & Benson, L.L.P., 2200 Norwest Center, 90 Seventh Street South, Minneapolis, MN 55402-3901 (for respondent)

Considered and decided by Amundson, Presiding Judge, Peterson, Judge, and Foley, Judge.[*]

 U N P U B L I S H E D   O P I N I O N

 PETERSON, Judge

Appellants Jeffery L. Palmer and Lisa Palmer challenge the district court's dismissal of their medical malpractice action for failure to serve an affidavit of expert identification as required by Minn. Stat. § 145.682, subds. 2(2), 4 (1998). We affirm.

 FACTS

  Jeffery Palmer received dental treatment from respondent John C. Erlandson in July 1996 and experienced complications. The Palmers retained counsel who wrote to Erlandson in October 1997 informing him about the Palmers' malpractice claim and asking him to have his malpractice insurer contact Palmers' attorney. The insurer contacted counsel and requested, among other things, a settlement demand along with any expert reviews of the case.

In response, on January 29, 1998, counsel sent the insurer a settlement demand letter that included the following paragraph:

I have retained Dr. William D. Bethke, D.D.S., S.C., as my expert to review Mr. Palmer's case and render an opinion with respect to the care that was given by Dr. Erlandson. I have enclosed for your reference * * * a copy of Dr. Bethke's December 3, 1997 report. Dr. Bethke's professional opinion is that had Mr. Palmer been premedicated, or if not premedicated, if he had been placed on antibiotics the day of treatment, then Mr. Palmer would not have developed the complications that he did. Further, it is Dr. Bethke's opinion that Dr. Erlandson failed to use that degree of care, skill and learning which is normally used by a dentist practicing general dentistry and that the failure of Dr. Erlandson to place Mr. Palmer on antibiotics was the direct cause of the complications. Dr. Erlandson was negligent and committed malpractice. He is therefore responsible for Mr. Palmer's damages.

Dr. Bethke's December 3, 1997, report was a one-page letter that stated:

Pursuant to your request, I have reviewed Jeffrey Palmer's dental records surrounding the incident with Dr. John Erlandson that occurred on or about July 11, 1996, along with the information provided by Mr. Palmer pertaining to this incident. Given the fact that he presented to Dr. Erlandson's office with an infection radiating to the back of his jaw, and given his limited ability to open completely - a condition called trismus - the appropriate treatment would have been to pre-medicate Mr. Palmer before treatment was started. We would like to see the patient on antibiotics 24 hours before a removal. If that is not possible, we would then do the necessary treatment to relieve the patient of pain, which in this case was the removal of a wisdom tooth. The patient would then be placed on antibiotics the same day for a ten-day regiment: usually 500 mg of Penicillin - 40 tabs.

My opinion is that the patient should have been pre-medicated, and if not pre-medicated, he should have been placed on antibiotics the day of treatment. By failing to do either of these things, Dr. Erlandson failed to use that degree of care, skill and learning which is normally used by a dentist practicing general dentistry. The failure was the direct cause of Mr. Palmer's complications.

The Palmers and Erlandson's malpractice insurer were unable to reach a settlement, and on February 28, 1998, the Palmers served Erlandson with a summons and a complaint. Pursuant to Minn. Stat. § 145.682, subds. 2(1), 3(a) (1998), an affidavit of expert review was served with the summons and complaint.

Erlandson answered the complaint, and the parties' depositions were taken on May 21, 1998. Erlandson acknowledged during his deposition that he had reviewed Bethke's December 3, 1997, report. Following the depositions, the parties' counsel discussed settlement and whether direct negotiations or mediation would be appropriate. There were further discussions about settlement during June 1997, and on August 19, 1998, following a request from defense counsel, Palmers' attorney sent defense counsel a copy of the January 29, 1998, settlement demand letter along with an updated analysis of liability based on the deposition testimony. There were further discussions between counsel about possible mediators, and on October 28, 1998, all counsel agreed upon a mediator and that mediation would take place on December 23, 1998.

On November 20, 1998, Erlandson moved for mandatory dismissal pursuant to Minn. Stat. § 145.682, subd. 6 (1998), because Palmers had failed to serve him with an affidavit of expert identification within 180 days after commencing suit as required by Minn. Stat. § 145.682, subds. 2(2), 4 (1998). On December 4, 1998, Palmers moved for an extension of time to serve the required affidavit. They included with their motion a supplemental affidavit identifying Bethke as their trial expert and a copy of Bethke's December 3, 1997, letter.

The district court denied Palmers' motion for an extension and dismissed their claim against Erlandson with prejudice. The court concluded that dismissal was mandatory because appellants' settlement letters failed to satisfy the requirements of Minn. Stat. § 145.682, subds. 2(2), 4.

 D E C I S I O N

 I.

  Palmers acknowledge that they did not timely serve an affidavit of expert identification, but they argue that the district court abused its discretion by dismissing their claim with prejudice because the information they provided Erlandson within 180 days after commencing suit met the disclosure requirements of Minn. Stat. § 145.682, subd. 4 (1998). Palmers contend that the settlement demand letter they submitted to Erlandson in August 1998, along with a copy of Bethke's December 3, 1997, letter report, contained the information that must be included in an affidavit of expert identification.

A district court's decision to dismiss a medical malpractice action for failing to comply with the disclosure requirements of Minn. Stat. § 145.682 will be reversed on appeal only if the district court has abused its discretion. Sorenson v. St. Paul Ramsey Med. Ctr., 457 N.W.2d 188, 190-91 (Minn. 1990). "Statutory construction, however, is a question of law and subject to de novo review on appeal." Id. at 190.

Within 180 days after commencing a medical malpractice action that requires expert testimony to establish a prima facie case, the plaintiff must serve upon the defendant an affidavit that states

the identity of each person whom plaintiff expects to call as an expert witness at trial to testify with respect to the issues of malpractice or causation, the substance of the facts and opinions to which the expert is expected to testify, and a summary of the grounds for each opinion.

Minn. Stat. § 145.682, subd. 4(a).

This affidavit must be signed by each expert listed in the affidavit and by the plaintiff's attorney. Id. The supreme court has also explained that in the affidavit, plaintiffs must set forth

specific details concerning their experts' expected testimony, including the applicable standard of care, the acts or omissions that plaintiffs allege violated the standard of care and an outline of the chain of causation that allegedly resulted in damage to them.

Sorenson, 457 N.W.2d at 193. It is not sufficient to repeat the facts in the medical records; instead, the affidavit must explain "how the expert will use those facts to arrive at opinions of malpractice and causation." Id. at 192; see also Stroud v. Hennepin County Med. Ctr., 556 N.W.2d 552, 555-56 (Minn. 1996) (following Sorenson).

Failure to provide the affidavit required under Minn. Stat. § 145.682, subd. 2(2), results, upon motion, in mandatory dismissal with prejudice of each cause of action that requires expert testimony to establish a prima facie case. Minn. Stat. § 145.682, subd. 6 (1998); see also Bjorke v. Mayo Clinic, 574 N.W.2d 447, 450 (Minn. App. 1998) (plaintiff's failure to provide either the affidavit of expert review, Minn. Stat. § 145.682, subd. 2(1), or the affidavit of expert identification, Minn. Stat. § 145.682, subd. 2(2), requires mandatory dismissal with prejudice). The supreme court recently stated:

Dismissal is mandated under Minn. Stat. § 145.682, subd. 6 when the disclosure requirements are not met and while we certainly recognize that the statute may have harsh results in some cases, it cuts with a sharp but clean edge. It is the legislative choice to implement the policy of eliminating frivolous medical malpractice lawsuits by dismissal. A showing of good cause for an extension of the 180-day time limit pursuant to Minn. Stat. § 145.682, subd. 4(b) may justify relief from the mandatory filing time required under the statute, but failing that, the statute compels dismissal for failure to timely file the required disclosure.

Lindberg v. Health Partners, Inc., 599 N.W.2d 572, 578 (Minn. 1999).

The documents that Palmers provided to Erlandson failed to meet the requirements of Minn. Stat. § 145.682, subds. 2(2), 4 (1998), in several respects. The documents were not in the form of affidavits or answers to interrogatories, and neither document was signed by both Palmers' expert and their attorney. Minn. Stat. § 145.682, subd. 4(a), explicitly requires that the disclosure of the identity of each expert that the plaintiff expects to call as a witness at trial be in the form of affidavits or answers to interrogatories and be signed by each expert and by the plaintiff's attorney. Also, the documents were not served on Erlandson as required by Minn. Stat. § 145.682, subd. 2(2). Although we recognize that the failure to meet these purely procedural requirements did not affect the content of the documents or the information actually communicated to Erlandson, we cannot ignore these explicit statutory requirements. But our decision does not rest on these procedural defects because we also conclude that the documents did not provide Erlandson with the information that the statute requires to be included in an affidavit of expert identification.

Neither letter identified Bethke as an expert whom Palmers expected to call as an expert to testify at trial. The letters indicate only that Bethke was retained as an "expert to review Mr. Palmer's case and render an opinion." Also, the letters do not state the substance of the facts that Bethke relied on to reach his opinion. Bethke's letter states only that he reviewed Jeffery Palmer's dental records "along with the information provided by Mr. Palmer pertaining to this incident." Bethke does not indicate what facts Palmer provided or explain how he used those facts to arrive at his opinions of malpractice and causation. Bethke does not even identify what complications Mr. Palmer suffered, much less explain how those complications were caused by Erlandson.

Bethke stated that Erlandson's failure to administer antibiotics violated the standard of care, but he failed to provide a summary of the grounds for his opinion that the applicable standard of care required Erlandson to administer antibiotics. The letter does not provide details about Bethke's qualifications to state the applicable standard of care or refer to any authority that indicates the applicable standard of care. By not providing any of this information, the letters failed to meet the requirements of Minn. Stat. § 145.682, subd. 4(a).

 II.

  Palmers argue that the district court abused its discretion by concluding that Erlandson was not estopped from seeking mandatory dismissal pursuant to Minn. Stat. § 145.682, subd. 6. They contend that Erlandson should have been equitably estopped from seeking a dismissal because his affirmative actions throughout the lawsuit, including participation in settlement discussions and court-ordered mediation, led them to believe that the affidavit of expert identification was not going to be an issue.

Equitable estoppel is a doctrine designed to prevent a party from unfairly benefiting from the party's own actions. Bethesda Lutheran Church v. Twin City Constr. Co., 356 N.W.2d 344, 349 (Minn. App. 1984), review denied (Minn. Feb. 5, 1985).

Estoppel is ordinarily a question of fact and the district court's decision will not be disturbed unless it is manifestly and palpably contrary to the evidence.

In re Liquidation of Excalibur Ins. Co., 519 N.W.2d 494, 498 (Minn. App. 1994), review denied (Minn. Oct. 14, 1994). To establish a claim of estoppel, Palmers had the burden of proving that (1) Erlandson knowingly misrepresented a material fact; (2) Erlandson intended to induce action as a result of the misrepresentation; (3) they lacked knowledge of the true facts; and (4) they relied upon Erlandson's misrepresentation to their detriment. Id.

To conclude that Erlandson should be estopped from seeking dismissal we would have to conclude that his participation in settlement discussions and mediation without objecting to Palmers' failure to serve an affidavit of expert identification was an attempt to knowingly misrepresent to Palmers that he considered their settlement demand letter and Bethke's report sufficient to serve as an affidavit of expert identification and thereby induce Palmers to refrain from serving an affidavit. We see no basis for treating Erlandson's participation in the lawsuit without objecting to Palmers' failure to serve the affidavit as a representation of any kind.

Erlandson had no obligation to inform Palmers that they were required to serve an affidavit of expert identification. Therefore, there was no basis for Palmers to draw any meaning from his participation in the lawsuit without informing them that they needed to serve the affidavit. See Stroud, 556 N.W.2d at 557 (fact that a party may rely on the opposing party's withdrawal of a motion to compel answers to interrogatories as signifying acceptance of answers to interrogatories in satisfaction of the requirements of Minn. Stat. § 145.682 does not mean that a party can rely on the opposing party's failure to bring a motion to compel as signifying the same thing where there is no obligation on the opposing party to bring such a motion).

 III.

  Palmers also argue that the district court abused its discretion by not extending the 180-day time period to provide the affidavit of expert identification because Erlandson would not have been prejudiced by an extension.

Minn. R. Civ. P. 6.02 is consistent with and applies to malpractice actions that are subject to the requirements of Minn. Stat. § 145.682. Parker v. O'Phelan, 414 N.W.2d 534, 537 (Minn. App. 1987), aff'd by an equally divided court, 428 N.W.2d 361 (Minn. 1988). Minn. R. Civ. P. 6.02 permits a trial court to extend a time limit under certain circumstances. This court will not reverse a district court's denial of a motion for an extension under rule 6.02 unless the district court abused its discretion. Id.

The time may be enlarged "upon motion made after the expiration of the specified period * * * [if] the failure to act was the result of excusable neglect." Minn. R. Civ. P. 6.02(2). To establish excusable neglect Palmers must demonstrate that (1) they have a reasonable case on the merits; (2) they have a reasonable excuse for failing to meet the time limit; (3) they exercised due diligence after notice of the time limit; and (4) Erlandson will suffer no substantial prejudice. Parker, 414 N.W.2d at 537.

The district court denied Palmers' motion for an extension of time to serve the affidavit of expert identification because it concluded that Erlandson's attorney's failure to warn Palmers that the affidavit may be an issue did not constitute a reasonable excuse for the failure to serve the affidavit. We agree.

As we have already stated in our discussion of estoppel, Erlandson had no obligation to inform Palmers that the affidavit was necessary. The affidavit was required by statute, and it was not reasonable for Palmers to conclude that Erlandson's participation in the lawsuit excused them from complying with the statute. Erlandson never indicated that the affidavit was not necessary. He simply treated the action seriously and took steps to protect his interests. The fact that Erlandson may not be prejudiced by an extension of the time limit does not make his participation in the lawsuit a reasonable excuse for Palmers' failure to comply with the statute.

Affirmed.

[*] Retired judge of the Minnesota Court of Appeals, serving by appointment pursuant to Minn. Const. art. VI, § 10.