The relation between dentistry and joint infection

Fraser Macdonald, Dental Tribune International

Thu. 6. November 2025

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LEIPZIG, Germany: As the global population ages, the number of total joint arthroplasties (TJAs), particularly of the hip and knee, correspondingly increases. Between 1% and 2% of these surgical procedures result in peri-prosthetic joint infection (PJI).¹ A substantial body of literature has explored the connections between these life-threatening infections and oral health, though reaching scientific and professional consensus has proved intractable. In this article, the most salient threads in the discussion are explored and the current state of knowledge described.

Postoperative peri-prosthetic joint infection

The onset of PJI varies widely, from within four weeks up to two years postoperatively. The gravity of PJI is clear: it is, according to a recent study, a “rare, but devastating complication” with a mortality rate as high as 11%.² In addition, it poses significant financial and psychological burden. Speaking on this severe diagnosis, Benjamin Kujat, training to be a specialist in orthopaedics and trauma surgery and an active researcher in this field, told Dental Tribune International that “despite the low prevalence of PJI, the resulting limitations and consequences for patients can be devastating. Treatment often requires multiple surgical interventions and weeks of antibiotic therapy, involves prolonged periods of suffering, and usually leads to a markedly worse functional outcome compared with the preoperative condition.” Moreover, the economic burden on the healthcare system is immense. Based on statistical data from 2002 to 2017, the cost of treating peri-prosthetic infections in the US by 2030 has been estimated at US$1.85 billion (€1.53 billion^*).³ Given that each case can cost up to US$100,000 to manage, the financial burden is disproportionately high. Therefore, for both patients and the healthcare system, each case is one too many.

While the majority of these infections originate in the peri-prosthetic tissue, secondary infections may arise from the oral cavity through the bloodstream. In this context, recent research has shown that “oral foci are not primarily causative for EP [endo-prosthesis] infection, but represent an important reservoir for EP colonisation”.⁴ This potential source of infection is of particular concern for dentists. In this respect, Kujat stated that “existing research has shown that there is a significantly higher incidence of joint infections caused by oral bacteria than from other sources. This finding indicates that joint prostheses are at risk of haematogenous infections originating from the oral cavity. Dental procedures are highly relevant because of both their frequency and the lack of awareness of the connection between bacteraemia after dental procedures like extraction and joint infections around artificial surfaces without immune response capabilities. So, in my opinion, dental procedures have a significantly higher risk because they occur very often”. So, where does dentistry fit into the treatment of this complex scenario?

Benjamin Kujat, a specialist-in-training in orthopaedics and trauma surgery and an active researcher in this field. (Image: Benjamin Kujat)

The role of dentistry

Dental procedures are believed to potentially introduce oral bacteria into the bloodstream, creating a risk of colonisation on prosthetic joint surfaces and the subsequent development of PJI. Speaking in a press release accompanying the publication of the American Academy of Orthopaedic Surgeons (AAOS) practical clinical guidelines for the prevention of total hip and knee arthroplasty PJI in patients undergoing dental procedures, board-certified orthopaedic surgeon Dr Yale Fillingham stated that “PJI is one of the most devastating complications for patients following TJA, and we must do everything possible that is supported by evidence to prevent these infections. Given the large number of annual TJA procedures and that most of these patients undergo a dental cleaning at least twice a year, [these guidelines are] relevant to nearly every TJA patient.”⁵ The overarching goal in this respect is for dentists to utilise all means at their disposal in order to prevent the migration of bacteria from the oral cavity to the prosthetic site as a direct result of dental procedures conducted prior to or after the joint replacement surgery. While a variety of measures have been proposed, their efficacy in reducing the risk of PJI, as well as the causal link between dental procedures and PJI more generally, is far from definitive.

A common practice is the use of antibiotic prophylaxis in TJA patients before invasive dental procedures, driven partly by the expectations of both orthopaedic surgeons and their patients. Indeed, as shown in the AAOS guidelines, the annual cost of dental antibiotic prophylaxis in the US alone for patients undergoing TJA is US$59 million.⁶ The question is whether the prophylactic use of antibiotics in this context has any evidence to support it. The literature almost unanimously reports that there is very little connection between invasive dental procedures and the occurrence of PJI and that therefore the prophylactic use of antibiotics in TJA patients is not well supported.

“While obvious dental issues can be examined easily by an orthopaedist, some hidden potential sources of infection can only be diagnosed by a dentist with his or her more specialised tools and experience.” — Benjamin Kujat

A Taiwanese study found that the “risk of PJI is not increased following dental procedures in patients with hip or knee replacement and is unaffected by antibiotic prophylaxis.”⁷ An American study found there to be “no significant positive association between [invasive dental procedures] and subsequent development of [late PJIs] and no significant effect of [antibiotic prophylaxis] in reducing [late PJIs]”,⁸ and another American study similarly found that “antibiotic prophylaxis prior to dental procedures did not decrease the risk of subsequent total hip or knee infection”.⁹ While the scientific verdict is clear, the practice is however likely to continue owing to dentists’ belief in its efficacy, combined with the expectations of orthopaedic surgeons and their patients alike.

Despite the lack of empirical evidence linking the spread of oral bacteria to infection at the prosthetic site, dental screenings are commonly performed prior to TJA to identify potential sources of bacteria that might pose a postoperative risk. As with antibiotic prophylaxis, this strategy has been subject to careful study. An American study that compared over 8,000 patients who underwent a dental screening prior to TJA against a cohort that did not reported that it “did not find that dental clearance decreases the rate of infection and also did not show a difference in organism profile between infections after dental clearance versus no dental clearance”.¹⁰ Similarly, an important German study found “no general association between early infection rate and preoperative oral screening”.¹¹ So, is dental screening of no significance to this type of infection? A vital part of the German study was the comparison of PJI frequency between patients screened by a dentist and those screened by an orthopaedic surgeon. The result of this investigation was that “100% of observed infections in the screening group occurred in the group with previous oral screening by an orthopaedic surgeon”. Kujat explained the technical origins of this finding: “While obvious dental issues can be examined easily by an orthopaedist, some hidden potential sources of infection can only be diagnosed by a dentist with his or her more specialised tools and experience, such as periodontitis, apical lesions or root inflammation.” So, while preoperative dental screening in general may not be associated with the occurrence of infection screening by a dentist appears to significantly affect detection of infection risk.

Another American study explored the relationship between oral health and postoperative PJI not in terms of antibiotics or screening but the absence or presence of natural dentition.¹² The research, which reviewed 1,157 medical charts, found that dentate patients had a nearly threefold higher rate of PJI compared with edentulous patients. The study highlights the need for further investigation into whether dentition status should inform postoperative monitoring protocols or preoperative dental assessment in TJA patients.

While the relationship between dental procedures and joint infection is complex and not entirely understood, most clinicians continue to adopt a conservative, cautious approach to the matter. (Image: prostooleh/Adobe Stock)

A final strategy available to mitigate the risks of bacterial transfer from the oral cavity to the prosthetic site is to delay the joint replacement surgery, thereby eliminating the potential for infection to occur as a result of transient bacteraemia, invasive dental procedures or the treatment of a dental infection. This is an option suggested in the updated AAOS clinical guidelines. In this light, should dentists support the delay of hip and knee replacement surgeries owing to a risk of exposing their patients to bacterial transmission? The AAOS guidelines suggest that non-invasive dental procedures such as scaling may cause brief bacteraemia that resolves within a day, allowing them to be safely performed until the day before elective TJA. In contrast, oral surgical procedures such as extractions require healing of a few days to two weeks. In patients with slower healing, such as those with diabetes, this may extend to three weeks. Since bacteraemia risk decreases once epithelialisation is complete, a three-week waiting period is recommended before proceeding with TJA after oral surgery. Active dental infections require antibiotics and often extraction or root canal treatment, and surgery should be postponed until the infection is fully resolved.

Concluding remarks

Postoperative PJI is a rare but serious complication of TJA, carrying significant medical, financial and psychological burden. While oral bacteria have long been suspected as a source, current evidence shows little causal connection between dental procedures and PJI. Antibiotic prophylaxis and preoperative dental screening, though widely practised, appear to provide minimal benefit, and their routine use rests on weak scientific foundations. Timing remains important: routine dental care is safe immediately before surgery, but oral surgery should precede TJA by three weeks, and active infections must be fully resolved. The debate continues, but caution and individualised care remain central.

Editorial note:

^* Calculated on the OANDA platform for 9 December 2020. A full list of references is available here.