Jaquez vs Nguyen et al

TENTATIVE RULING(S) FOR September 1, 2026 Department S37 – Judge Winston Keh This court follows California Rules of Court, rule 3.1308(b) for tentative rulings. (See San Bernardino Superior Court Local Emergency Rule 8.) Tentative rulings for each law & motion will be posted on the internet (https://www.sb-court.org) by 3:00 p.m. on the court day immediately before the hearing.

You may appear in person at the hearing although remote appearance by CourtCall is preferred. (See www.sb-court.org/general-information/remote-access).

If you do not have Internet access or if you experience difficulty with the posted tentative ruling, you may obtain the tentative ruling by calling the department (S-37) at (909) 708-8707 or the Administrative Assistant (909) 708-8756, who prepared the ruling.

If you (or both parties) wish to submit on the Tentative, notify the other party and call the department by 4:00 pm the day before and your appearance may be excused unless the Court orders you to appear.

You must appear at the hearing if you are so directed by the court in the tentative ruling. Be prepared to address those issues set forth by the court in its ruling.

UNLESS OTHERWISE NOTED, THE PREVAILING PARTY IS TO GIVE NOTICE OF THE

RULING.

Jaquez vs Nguyen et al

__________________________________________________________________________

TENTATIVE RULING(S):

RELEVANT FACTS

On March 26, 2024, Plaintiff Oscar Jaquez filed a Complaint against Defendant Sang Woo Kim,

DDS. On June 30, 2025, Plaintiff filed an Amendment to Complaint naming Hoang Nguyen, DDS

as Doe 1. After Nguyen was named, Plaintiff dismissed Defendant Kim on July 14, 2025.

Defendant Hoang Nguyen, DDS answered on September 18, 2025.

Plaintiff alleges one cause of action for dental negligence. Plaintiff alleges that Defendants were

negligent in providing dental care to him in January 2023.

Before the Court is Defendant Nguyen’s motion for summary judgment or, in the alternative,

summary adjudication. Defendant argues that Plaintiff’s negligence cause of action is time-

barred by the statute of limitations. He also contends that Defendant’s treatment of Plaintiff met

the standard of care and that no act or omission by Defendant caused Plaintiff’s injuries.

Plaintiff opposes. Defendant replies.

ANALYSIS

Plaintiff’s Request for Judicial Notice

Plaintiff requests the Court take judicial notice of Exhibits A and B to Defendant’s Compendium

of Exhibits filed in support of his motion for summary judgment. Those exhibits, consisting of

medical records (Exhibit A) and Plaintiff’s deposition (Exhibit B), are not the types of documents

of which the Court may take judicial notice. (Evid. Code, § 452.) The Court therefore DENIES

Plaintiff’s request for judicial notice. Nonetheless, because the documents were filed with

Defendant’s motion, the Court considered them in that context.

General Facts

Defendant offers UFs 1 through 27 generally. Facts that Plaintiff states are disputed are noted as

such.

This case arises from dental treatment provided to Plaintiff in January 2023. (UF 1.) Plaintiff filed

his Complaint on March 26, 2024. More than a year later, on June 30, 2025, Plaintiff filed a Doe

Amendment naming Defendant Hoang Nguyen, DDS. (UF 2.)

On the morning of January 28, 2023, Plaintiff began experiencing excruciating pain in the lower

right side of his mouth. Plaintiff searched for a dental provider and was seen that same day by

Dr. Nguyen. (UF 3.) Plaintiff’s medical history was reported on his intake forms and was marked

all negative, which indicated no blood pressure issues. (UF 4 – disputed.) Plaintiff asserts this is

disputed because the standard of care required obtaining and documenting vital signs before

treatment.

Diagnostic x-rays were taken. Plaintiff was seen by Dr. Nguyen and reported pain on the lower

right side of the mouth. (UF 5.) Plaintiff was missing a right lower back tooth #30 and had a

dental bridge over neighboring teeth #29, #30, and #31. On review of diagnostic imaging, Dr.

Nguyen noted Plaintiff had a lesion on a lower right molar tooth #31. (UF 6.) Dr. Nguyen’s

recommendations were for a root canal for tooth #31, or extraction, due to infection. Plaintiff

opted for extraction of tooth #31, which required cutting and splitting the existing dental bridge

over teeth #29, #30, and #31. (UF 7.)

The risks, benefits, and alternatives of treatment were discussed with Plaintiff, including risks of

potential nerve damage and indefinite paresthesia. Plaintiff provided his informed consent for

extraction of tooth #31 by Dr. Nguyen. (UF 8 – disputed.) Plaintiff asserts that the records do not

document that Plaintiff was informed of the risks and gave informed consent.

Dr. Nguyen proceeded with extraction of tooth #31. (UF 9.) After removal, Plaintiff had unusually

long bleeding at the extraction site. Pressure was applied, and Plaintiff’s blood pressure was

taken and noted to be elevated at 177/107. (UF 10.) Plaintiff was discharged with post-op

instructions to apply pressure if bleeding restarted at home and to present to the ER if the

bleeding did not stop. Plaintiff was prescribed Amoxicillin antibiotics and Norco for pain and was

recommended to see a physician for his blood pressure. (UF 11.)

Later that evening, at 8:30 p.m., Dr. Nguyen called Plaintiff, who reported that the bleeding was

under control and that Plaintiff had started antibiotics and pain medication. (UF 12.) On February

4, 2023, Plaintiff reported to Dr. Nguyen ongoing pain and swelling and that he had not

continued antibiotics. Defendant recommended that Plaintiff continue and finish the course of

Amoxicillin. A prescription for ibuprofen 800 MG was given by Defendant. (UF 13.)

Due to experiencing excruciating pain afterwards, Plaintiff began to suspect something had gone

wrong with the extraction of tooth #31 by Dr. Nguyen. (UF 14.) Plaintiff decided to see other

dental providers for a second opinion due to ongoing pain and numbness. (UF 15.) On February

7, 2023, Plaintiff was seen by another dental provider, Mei Lu, DDS, for comprehensive oral

evaluation and panoramic imaging. (UF 16.) On February 8, 2023, Plaintiff was seen by Dr.

Nguyen and reported worsened pain on the lower right side and numbness to the area.

Recommendations were to wait a week or two to see if numbness and pain resolved and, if no

improvement was seen, for referral to a specialist. (UF 17.)

Plaintiff obtained a second opinion from another dental provider around 10 days after the post

incident. (UF 18.) On February 9, 2023, Plaintiff was again seen by Mei Lu, DDS, and was noted

to have ongoing severe swelling and pain on the right side with right-sided tongue numbness

and lower lip numbness post extraction of tooth #31, and an abscess. Plaintiff was referred to

oral surgery for an infection and inferior alveolar nerve recovery treatment. (UF 19.)

Plaintiff sought treatment from a third dental provider, who indicated Plaintiff had suffered injuries

from the procedure by Defendant. (UF 20.) On February 9, 2023, Plaintiff was seen by Jone Kim,

DDS, MS, and was noted to have numbing in the area following surgical removal of erupted

tooth #31. Plaintiff underwent incision and drainage of an abscess at tooth #31. (UF 21.)

Due to Plaintiff’s ongoing complaints, Plaintiff was sent a prescription for an alternative antibiotic,

Cephalexin 500 mg, on February 10, 2023, by Defendant’s dental office. (UF 22.) On February

24, Plaintiff called Defendant’s office and reported swelling and that the Cephalexin had given

him a rash. Another alternative antibiotic, Azithromycin, was prescribed to Plaintiff by

Defendant’s dental office and recommendations were to return for a follow-up visit. (UF 23.)

On March 3, 2023, Plaintiff was seen by another provider at Defendant’s dental office, x-rays

were taken, and a small root tip of tooth #31 was visible. Plaintiff reported ongoing pain and

infection, numbness to the lower right lip area, and had finished his course of antibiotics. He also

reported that he had been seen for an oral surgery consultation with another provider the day

before on March 2, 2023. The plan was for a further round of antibiotics and to return the next

day to be seen by Defendant. (UF 24.)

On March 4, 2023, Plaintiff was seen by Dr. Nguyen, reported no pain, was feeling much better,

and had continued antibiotics. Dr. Nguyen explained that if pain returned, the root tip for tooth

#31 would need removal. Recommendations were for removal of distal root tip of tooth #31 by

oral surgery. Plaintiff demonstrated understanding but wanted to wait. This was the last time

Plaintiff was seen at Defendant’s office. (UF 25.)

On March 13, 2023, Plaintiff called Defendant’s dental office and requested a refill of antibiotics

and an upcoming March 16, 2023, appointment with oral surgery on “March 16, 223” for removal

of the root of tooth #31. Defendant’s dental office sent prescriptions to the pharmacy. (UF 26 –

disputed because of the typo.) Plaintiff contends Defendant meant to say 2023, not 223.

On March 20, 2023, Plaintiff was seen by Sang Woo Kim, DDS. The notes indicate that Plaintiff

presented with pain on the lower right and reported extraction of tooth #31 with sectioning of an

attached bridge, and thereafter had numbness and ongoing pain from the site tooth #32. The

assessment was infection of tooth #32 with associated right-sided V3 hypoesthesia. (UF 27.)

Discussion

1. Statute of Limitations

Defendant Nguyen offers UFs 28 through 32 in support of his argument that Plaintiff’s sole cause

of action is barred by the statute of limitations.

Code of Civil Procedure section 340.5 provides: “[A]n action for injury or death against a health

care provider based upon such person’s alleged professional negligence” must be brought within

“three years after the date of injury or one year after the plaintiff discovers, or through the use of

reasonable diligence should have discovered, the injury, whichever occurs first.”

There is no dispute here that the one-year period is applicable.

The one-year period under section 340.5 begins when a plaintiff suspects or has reason to

suspect that the plaintiff’s injury was caused by wrongdoing. (Brewer v. Remington (2020) 46

Cal.App.5th 14, 21 (Brewer).)

“‘The term “injury” for purposes of section 340.5 “‘refer[s] to the damaging effect of the alleged

wrongful act and not to the act itself.’ [Citation.] The injury is not necessarily the ultimate harm

suffered, but instead occurs at ‘the point at which “appreciable harm” [is] first manifested.’”

[Citation.] An injury manifests when damage is ‘evidenced in some significant fashion; when the

damage has clearly surfaced and is noticeable.’ [Citation].” (Filosa v. Alagappan (2020) 59

Cal.App.5th 772, 779.)

“Under the one-year limitation period of section 340.5, the plaintiff must bring suit within one year

after he or she discovers, or should have discovered, his or her injury. However, a plaintiff need

not be aware of either the specific facts or the actual negligent cause of the injury. [Citation.] If

the plaintiff has notice or information of circumstances that would put a reasonable person on

inquiry notice, the limitation period is activated. [Citation.] When this occurs, the ‘patient is

charged with “presumptive” knowledge of his negligent injury ... .’ [Citation.]” (Brewer v.

Remington, supra, 46 Cal.App.5th at p. 24.)

The undisputed facts establish that Plaintiff had discovered, or at minimum had reason to

suspect, appreciable harm caused by the extraction on or about February 9, 2023 - well before

one year before he filed his Complaint on March 26, 2024.

Defendant argues Plaintiff discovered, or reasonably should have discovered, his injury when he

visited other dentists for second opinions in February and March 2023. (Mtn. at pp. 10-11.) The

undisputed material facts establish that “[d]ue to experiencing excruciating [pain] after [the

procedure], Plaintiff began to suspect something had gone wrong with the subject extraction of

tooth #31 by Dr. Nguyen,” and “Plaintiff decided to see other dental providers for a second

opinion due to ongoing pain and numbness.” (UF 14, 15.)

Plaintiff saw Dr. Mei Lu, DDS, for comprehensive oral evaluation and panoramic imaging on

February 7, 2023. (UF 16.) Plaintiff then returned to Dr. Nguyen on February 8, 2023. (UF 17.)

On February 9, 2023, Plaintiff was seen again by Dr. Mei Lu, who referred him to oral surgery.

(UF 19.)

Also on February 9, 2023, Plaintiff was seen by Dr. Jone Kim, DDS, MS, and underwent incision

and drainage of an abscess. (UF 21.) Plaintiff communicated with Dr. Nguyen’s office regarding

his antibiotics on February 10 and 24, 2023. (UF 22, 23.) He was seen by another provider at Dr.

Nguyen’s office on March 3, 2023, and he was seen by Dr. Nguyen on March 4, 2023. (UF 24,

25.) Finally, Plaintiff was seen by Dr. Sang Woo Kim, DDS, on March 20, 2023. (UF 27.)

Plaintiff’s own deposition testimony confirms that, by February 9, 2023, he had sufficient

information to place him on inquiry notice of a potentially negligent injury. UF 20 is undisputed

and establishes that Plaintiff sought treatment from a third dental provider who indicated Plaintiff

had suffered injuries from the procedure by Defendant. In support of UF 20, Defendant cited to

Plaintiff’s deposition at pages 22:2-15, in which Plaintiff was testifying about visiting Dr. Jone Kim

and reported that Dr. Kim said, “‘Oh, man.’ ... ‘Man, that guy messed you up,’ ... ‘because he

took a tooth out that probably didn’t even need to come out. It was further back. But not only did

he take your tooth out, the reason you’re all numb is he messed up your nerve.’” (Def’s Ex. B –

Jaquez Depo p. 22:7-13.) Dr. Kim told Plaintiff he needed to go to UCLA. (Id. at p. 22:14.)

Plaintiff testified that Kim “scared the heck of [him]” and told Plaintiff he “better try to get in there

as soon as he can.” (Id. at p. 22:15-20.) From the records and UF 21, Plaintiff saw Dr. Kim on

February 9, 2023.

Even if Dr. Kim did not identify Dr. Nguyen by name, that fact does not alter the accrual of

Plaintiff’s claim. The governing authorities do not require a plaintiff to know the specific facts

constituting negligence or the identity of the precise negligent actor before the limitations period

begins to run. Rather, the period is triggered when the plaintiff discovers, or should have

discovered, the injury and has sufficient information to put a reasonable person on inquiry notice

of wrongdoing. (Brewer v. Remington, supra, 46 Cal.App.5th at p. 24.)

Here, Plaintiff does not dispute that, by February 9, 2023, he had been told that the extraction

had caused nerve damage and that the person who performed the extraction had “messed” him

up. Plaintiff was also directed to seek specialist treatment. These facts, together with Plaintiff’s

continuing pain, numbness, swelling, abscess, and repeated visits to other dental providers,

establish appreciable harm and inquiry notice no later than February 9, 2023.

Plaintiff asserts that two facts are disputed regarding when Plaintiff knew or should have known

about his injury, UFs 28 and 29.

With respect to UF 28, Defendant asserts that Plaintiff was told by later dental providers that the

extraction of tooth #31 by Dr. Nguyen caused resulting nerve damage. (UF 28 – disputed.)

Plaintiff asserts that the dentists did not identify the dentist who did it; they just said the

extraction caused a lot of problems, citing the same deposition testimony of Plaintiff that

Defendant cites in support of UF 28.

First, UF 20, which is that Plaintiff sought treatment from a third dental provider who indicated

Plaintiff had suffered injuries from the procedure by Defendant, is undisputed. In support of UF

20, Defendant cited to Plaintiff’s deposition at pages 22:2-15, in which Plaintiff was testifying

about visiting Dr. Jone Kim and reported that Dr. Kim said, “‘Oh, man.’ ... ‘Man, that guy messed

you up,’ ... ‘because he took a tooth out that probably didn’t even need to come out. It was

further back. But not only did he take your tooth out, the reason you’re all numb is he messed up

your nerve.’” (Def’s Ex. B – Jaquez Depo p. 22:7-13.) Dr. Kim told Plaintiff he needed to go to

UCLA. (Id. at p. 22:14.) Plaintiff testified that Kim “scared the heck of [him]” and told Plaintiff he

“better try to get in there as soon as he can.” (Id. at p. 22:15-20.) From the records and UF 21,

Plaintiff saw Dr. Kim on February 9, 2023.

With respect to the testimony cited in support of UF 28, Plaintiff testified that he went to the

doctor at UCLA. When asked if he was seen by someone at UCLA who told him he had damage,

Plaintiff responded in the affirmative, stating that “they sent me there to see – to get definite

knowledge that I was messed up.” (Def’s Ex. B, p. 23:12-17.) Although not cited by the parties,

when asked when this occurred, he stated it was February but then stated it was tough to get an

appointment, so it was either somewhere near the end of April or beginning of May. (Id. at p.

23:20-24.) He testified that the doctor at UCLA stated he had nerve damage because he had

some work done, the tooth taken out. He also testified that, “It’s the same thing that each one of

those – every single doctor that I saw said the same thing. They all said it. They said that – the

doctor that sent me to UCLA said – you asked about the name – I remember that doctor telling

me – he said, ‘Who took this tooth out for you?’ And I told him the name of the place at the time.

I don’t remember the name right now. But I told him the name of the place, and he said, ‘Just the

name should tell you not to go there’ or something.” (Id. at p. 24:12-21.)

When asked whether the other providers he saw shortly after because he was in excruciating

pain told him “‘Hey, this tooth didn’t need to be taken out, and you have nerve damage,’” he

eventually again discussed Dr. Jone Kim in which Plaintiff testified that Dr. Kim said, “‘Man, that

tooth – that one probably didn’t need to take out. Jacked you up in the process.’ That’s literally

what he said. He said that I got messed up in the process.” (Id. at pp. 25:24-25:2, 25:23-26:2.)

Even if the providers did not identify the specific dentist, Plaintiff does not dispute that at least as

early as Dr. Jone Kim on February 9, 2023, he was told that the person who did the extraction

“messed” Plaintiff up, caused nerve damage, and told Plaintiff he needed to see a specialist right

away. Plaintiff disputes that the later dentists identified Dr. Nguyen, but he does not dispute that

the later dentists told him that the extraction caused nerve damage. (UF 28.)

As for UF 29, Defendant states that due to these statements by later dental providers, Plaintiff

began suspecting wrongful treatment from Dr. Nguyen. (UF 29 – disputed.) Plaintiff asserts he

suspected the person who extracted tooth 31 may have committed malpractice, but that he did

not know who it was.

Again, Plaintiff cites to the same evidence that Defendant cites in support, which is Plaintiff’s

deposition testimony at page 27:3-11, in which Plaintiff was asked when he started thinking

something had gone wrong or something was done that shouldn’t have been done, and he

answered, “Well, because those dentists started telling me something was way wrong that

normally wouldn’t happen. I didn’t know what to think up until then....” (Def’s Ex. B at p. 27:3-8.)

Plaintiff concedes that he “suspected that the person who extracted tooth 31 ma[y] have

committed malpractice,” but contends “[h]e didn’t know who it was.” (UF 29.) The fact Plaintiff

asserts that he did not know the name of the dentist who did the extraction does not make it

disputed that Plaintiff began suspecting wrongful treatment due to the other dentist’s statements.

Plaintiff was told he would need nerve reattachment surgery to treat the resulting numbness by

later providers. (UF 30.) Plaintiff has an independent recollection of Dr. Nguyen, who Plaintiff

recalled as an Asian male dentist, and his initial visit with Dr. Nguyen and the subject extraction.

(UF 31 – disputed.) Plaintiff contends that he did not say he has an independent recollection of

Dr. Nguyen. He knows now that Dr. Nguyen performed the extraction, but he did not know that at

the time. Plaintiff cites his declaration in support.

Plaintiff’s disagreement about when he learned Dr. Nguyen’s identity does not create a triable

issue as to when the injury claim accrued. By February 9, 2023, Plaintiff had experienced

significant and continuing pain and numbness, had sought multiple second opinions, had been

told that the extraction had caused nerve damage, and had been referred to specialist for

treatment. These undisputed facts establish inquiry notice of appreciable harm and possible

wrongdoing.

Plaintiff’s later efforts to identify the precise dentist responsible do not postpone accrual of the

claim. Indeed, Plaintiff continued seeking treatment for the same condition through March 20,

2023. The cause of action therefore accrued no later than March 20, 2023. (Code Civ. Proc., §

340.5.)

Plaintiff filed his Complaint on March 26, 2024, against the dentist who performed the extraction,

albeit named as a Doe Defendant. The filing of Plaintiff’s Complaint was therefore untimely as to

the one-year limitations period.

2. The Naming of the Doe Defendant

Defendant also argues that Plaintiff improperly named Defendant Nguyen as a Doe Defendant

and Plaintiff should not have the benefit of Code of Civil Procedure section 474 because Plaintiff

admitted actual knowledge of Defendant Nguyen’s identity and role in the incident. While Plaintiff

disputes that he had an independent recollection of Dr. Nguyen, Defendant also argues that

Plaintiff had knowledge of Dr. Nguyen’s role in the incident and sufficient information to put a

reasonable person on inquiry notice of potentially wrongful conduct but took no action to name

Dr. Nguyen as a Doe Defendant until June 30, 2025, over two years later. He also argues that

the evidence demonstrates that Plaintiff requested his records from Defendant’s office and

signed an authorization for the release on August 18, 2023.

Plaintiff’s arguments in opposition center on whether Plaintiff reasonably should have identified

Dr. Nguyen as the correct Defendant earlier than the June 30, 2025, Doe amendment to his

Complaint. (Opp. at pp. 5-6.) While not cited in support of a disputed fact, Plaintiff argues that

the records from the day of the January 28, 2023 extraction do not contain the name of a dentist

or signature that was legible, citing Plaintiff’s declaration at paragraph 8. While Plaintiff’s counsel

states that a copy of the records from Nguyen Truong Dental Corp were requested, he states

they were not received, but he admits Plaintiff was able to obtain a copy. (Duke Decl. ¶ 5.)

Plaintiff contends that he reviewed his records with his attorney in preparation for filing suit, and

they saw a note regarding the extraction in Dr. Kim’s records, but the January 28, 2023 record of

the extraction itself did not indicate who performed it. (Opp. at p. 6.)

Dr. Kim is not affiliated with Dr. Nguyen’s office; she is the dentist Plaintiff visited on March 20,

2023, for second (or third) opinion. (UF 27.) In addition, it is undisputed that Plaintiff sought his

records from Defendant’s office in August 2023, and no explanation is provided as to why, with

reasonable diligence, Plaintiff could not have discovered the identity of the dentist who

performed the extraction on January 28, 2023. Notes in these records indicate they were first

given to Plaintiff’s wife in August 2023. (Def’s Ex. A, p. 14.)

Defendant’s reply focuses on the naming of Dr. Nguyen as a Doe Defendant, arguing Plaintiff is

not entitled to the benefit of section 474. (Reply at pp. 3-7.) He argues that on Exhibit A, the

medical records from Defendant, his name appears on pages 3, 10, and 11. This appears to be

in reference to the name of the dental practice, Nguyen Truong Dental Corp, appearing on the

documents. Nonetheless, when Exhibit A is reviewed for the diagnosis on January 28, 2023,

where it states, “Diagnosis by,” Nguyen is written. (Def’s Ex. A at p. 7.) As Defendant also points

out on reply, Dr. Nguyen’s initials are also seen on Exhibit A as the treating provider at pages 2,

6, 7, 8, and 9. When reviewed, the notes that follow for January 28, 2023, are signed by “Dr. N.”

(Id. at p. 8.) Defendant argues in reply that Plaintiff’s ignorance of Dr. Nguyen’s name was not

bona fide, so the June 30, 2025, Amendment to Complaint does not relate back to the

Complaint’s filing date of March 26, 2024. (Reply at pp. 4-5.) Defendant argues that Plaintiff

could not, in good faith, argue that he was ignorant of Dr. Nguyen’s identity until June 2025.

Code of Civil Procedure section 474 provides that “[w]hen the plaintiff is ignorant of the name of

a defendant, he must state that fact in the complaint, ... and when his true name is discovered,

the pleading or proceeding must be amended accordingly.” The purpose of the provision is to

enable a plaintiff who is truly ignorant of a defendant’s name to commence a suit before it is

barred by the statute of limitations. (Austin v. Massachusetts Bonding & Ins. Co. (1961) 56

Cal.2d 596, 602.) If properly amended, the pleading relates back to the date of filing of the

original complaint as to that defendant, provided the plaintiff seeks recovery on the same general

set of facts as the original complaint. (Streicher v. Tommy’s Electric Co. (1985) 164 Cal.App.3d

876, 882.)

The plaintiff’s ignorance of either the defendant’s true identity or the facts giving rise to a cause

of action against that defendant must be real and not feigned; the question of whether the

plaintiff has invoked section 474 in good faith rests with the trial court. (Woo v. Superior Court

(1999) 75 Cal.App.4th 169, 177.) Unless the pleading requirements of section 474 are met, a

plaintiff may not take advantage of the provisions of section 474 and later substitute a person in

the place of a fictitious defendant. (Id. at p. 176.)

Here, the undisputed facts establish that Plaintiff had repeated contact with Dr. Nguyen’s office

and had ample opportunity to determine the identity of the dentist who performed the January

28, 2023 extraction.

The undisputed facts establish that Plaintiff saw Dr. Nguyen, or at least visited or called his

office, on January 28, 2023 (UF 3); February 4, 2023 (UF 13); February 8, 2023 (UF 17);

February 24, 2023 (UF 23); March 3, 2023, although Plaintiff saw another provider at

Defendant’s office that day (UF 24); March 4, 2023 (UF 25); and March 13, 2023 (UF 26).

Additionally, Plaintiff signed an authorization for release of his records from Defendant’s office on

August 25, 2023. (UF 32.)

The records state that Dr. Nguyen performed the diagnosis on January 28, 2023. (Def’s Ex. A at

p. 7.) The handwritten notes regarding the extraction are signed, “Dr. N.” (Def’s Ex. A at p. 8.)

The x-rays are captioned, “Nguyen Truong Dental Corp,” and the provider on the x-rays is listed

as Tiffany Truong. (Def’s Ex. A at p. 11.) The provider’s name on the Amoxicillin prescription is

“Hoang Nguyen.” (Def’s Ex. A at p. 12.)

It is undisputed that, as of the filing of the Complaint, Plaintiff knew his negligence cause of

action was directed to the doctor who performed the extraction on January 28, 2023, and had

the medical records from Defendant’s office for that date. The records identified the dental office

and contained multiple references to Nguyen, including an identification of Nguyen as the doctor

who diagnosed Plaintiff on January 28, 2023, handwritten notes signed “Dr. N.,” and a

prescription identifying “Hoang Nguyen” as the provider.

Under these circumstances, Plaintiff has not established the type of genuine ignorance

contemplated by Code of Civil Procedure section 474. Even accepting Plaintiff’s assertion that

he did not immediately know Dr. Nguyen’s full name, the undisputed evidence demonstrates that

he possessed information that would have enabled him, with reasonable diligence, to identify the

dentist who performed the extraction well before June 30, 2025.

More importantly, however, the Doe issue is not necessary to the disposition of the motion. Even

if Plaintiff were entitled to invoke Code of Civil Procedure section 474 and even if the June 30,

2025, amendment related back to the original Complaint, Plaintiff’s action would remain untimely

because the cause of action accrued no later than March 20, 2023, and the original Complaint

was not filed until March 26, 2024.

Accordingly, Plaintiff cannot avoid the statute of limitations through the Doe amendment.

3. Negligence

A claim for professional negligence requires proving (1) the defendant had a duty to use such

skill, prudence, and diligence as other members of the profession commonly possess and

exercise, (2) the defendant breached that duty, (3) a proximate causal connection between the

negligent conduct and the plaintiff’s injury, and (4) actual loss or damages. (Hanson v. Grode

(1999) 76 Cal.App.4th 601, 606.)

In professional malpractice cases, “expert opinion testimony is required to prove or disprove that

the defendant performed in accordance with the prevailing standard of care, except in cases

where the negligence is obvious to laymen.” (Garibay v. Hemmat (2008) 161 Cal.App.4th 735,

741.) Similarly, medical causation can only be determined through an expert medical testimony.

(Salasguevara v. Wyeth Laboratories, Inc. (1990) 222 Cal.App.3d 379, 385.) An expert’s opinion

that no breach occurred or no causation exists is sufficient to support summary judgment where

the plaintiff fails to submit any opposing expert opinion. (Jambazian v. Borden (1994) 25

Cal.App.4th 836, 850.) However, “an opinion unsupported by reasons or explanations does not

establish the absence of a material fact issue for trial, as required for summary judgment.”

(Kelley v. Trunk (1998) 66 Cal.App.4th 519, 524.)

Defendant offers UFs 33 through 44 in asserting he complied with the standard of care and that

no negligent act or omission by Defendant caused or contributed to Plaintiff’s injuries. The

parties dispute whether Dr. Nguyen was negligent in failing to refer Plaintiff to an oral surgeon on

January 28, 2023 (UF 34); whether Dr. Nguyen adequately informed Plaintiff of the risks of the

procedure (UF 36); whether the extraction itself was not within the standard of care (UF 37);

whether the follow-up care was not within the standard of care (UF 39); and whether to a

reasonable degree of medical certainty, an act or omission by Dr. Nguyen caused or contributed

to Plaintiff’s alleged injuries. (UF 44.)

The parties have submitted competing expert declarations regarding whether Dr. Nguyen’s

actions met the applicable standard of care and caused or contributed to Plaintiff’s injuries.

(Garabedian Decl. ¶ 3; Javidzad Decl. ¶¶ 21-23.) On reply, Defendant does not seek to discredit

Plaintiff’s experts. The question of negligence therefore depends upon disputed material facts,

so Defendant is not entitled to summary judgment on that ground.

This conclusion does not affect the disposition of the motion. Because Plaintiff’s claim is barred

by the statute of limitations, the existence of disputed factual issues concerning the standard of

care, breach, or causation does not preclude judgment in Defendant’s favor.

CONCLUSION

The undisputed evidence establishes that Plaintiff’s professional-negligence claim accrued no

later than March 20, 2023, when, following the January 28, 2023, extraction, Plaintiff had

experienced continuing pain and numbness and had received information from subsequent

dental providers sufficient to put him on inquiry notice of appreciable harm and potential

wrongdoing. (Code Civ. Proc., § 340.5.)

Plaintiff did not file his Complaint until March 26, 2024, more than one year after the cause of

action accrued. His subsequent June 30, 2025, Doe Amendment does not cure the untimeliness

of the action. Moreover, the undisputed evidence does not establish the bona fide ignorance

required to invoke Code of Civil Procedure section 474.

Accordingly, Defendant Hoang Nguyen, DDS’s Motion for Summary Judgment is GRANTED.

The Court need not, and does not, reach the merits of Plaintiff’s claims concerning the applicable

standard of care or causation because the action is barred by the statute of limitations.

Judgment shall be entered in favor of Defendant Hoang Nguyen, DDS and against Plaintiff

Oscar Jaquez.