Advancing Implant Dentistry: A Conversation With Dr. Hom-Lay Wang
More than 50 years ago, dentistry was gifted the breakthrough of osseointegration by Prof. Per-Ingvar Brånemark and Prof. André Schroeder. This clinical “miracle,” in which living bone fuses directly to titanium, has transformed dentistry by providing solutions for bone-anchored prosthetic replacement of teeth without compromising the natural dentition.
Unfortunately, there has been a dramatic rise in complications in recent years, with peri-implantitis being the most concerning of all. Recent data indicate that the prevalence of peri-implantitis ranges from 18% to 25% of patients and about 12% to 18% of implants.¹,² Over a four-year period, the incidence of peri-implantitis was reported to be about one in five patients and one in 10 implants, of which about half were new peri-implantitis cases and half were regression of existing peri-implantitis.³ These prevalence rates are alarmingly high and would set alarm bells ringing if similar figures were reported for prosthetic joint replacements in the medical field. The good reputation of implant therapy as a predictable treatment option is at risk.
Why is this happening? First, there was a paradigm shift from machined to micro-rough implant surfaces in the late 1990s because they offer several clinical advantages, such as acceleration of osseointegration, increased boneto-implant contact that improves predictability, especially in low-density bone and with short implants, and shorter healing periods.4 But there was a biological trade-off. If the micro-rough implant surface is exposed to the peri-implant sulcus, it becomes susceptible to biofilm contamination.
Compared with machined surfaces, micro-rough surfaces have significantly greater bacterial adhesion and trigger a stronger immune response.5,6
Several long-term studies showed a clearly higher prevalence of peri-implantitis for implants with a micro-rough surface in the transcrestal area compared with machined surfaces.7-10
In a 2026 review article by Chen et al., 10 leading experts concluded that clinician-related errors during implant therapy are a significant driver of peri-implantitis and, therefore, peri-implantitis should be regarded as a complication of implant therapy rather than a disease in the classical sense.11 The exposure of the micro-rough implant surface to the sulcus was identified as the main predisposing factor for the initiation of peri-implantitis.
As a consequence, the authors recommended the use of implants with a hybrid surface design, as first proposed by Dennis Tarnow in 1993.12 These implants have a micro-rough surface for endosseous anchorage and a machined surface collar. In cases of crestal bone resorption, the machined surface is exposed rather than the micro-rough surface.
The second factor leading to the rise in the prevalence of peri-implantitis is the success of osseointegration itself. With increased predictability of osseointegration and the exceptionally high initial success rates of dental implants, the number of patients receiving implant therapy has increased exponentially over the past two decades. Today, implant therapy is often considered the treatment of choice for the replacement of missing teeth.
The estimated compound annual growth rate in the market for implant therapy is about 8%.13 This translates to a doubling of the market size every nine years, driven by increasing demand for dental implants. Until the turn of the millennium, dental implants were primarily the domain of specialists with expertise in surgery. Since then, there has been an increase in the number of general dental practitioners incorporating the surgical placement of implants into their practices.14 Without comprehensive education and training, there has been an increase in complications, with some dentists attempting complex cases without sufficient experience and expertise. It is very likely that this trend is, in part, responsible for the increased rate of complications and prevalence of peri-implantitis in the market.
Incredibly, a recent study estimated that treatments for peri-implantitis may surpass those for periodontitis in Europe and the U.S. in the near future.15
The third factor in the rise of peri-implantitis prevalence relates to the quality of treatment provided by dentists. As discussed above, the clinical reality is that the majority of peri-implantitis cases are initiated by errors during the surgical placement or subsequent restoration of implants. In a recent report, an overwhelming 71% of peri-implantitis cases could be attributed to treatment errors. In other words, the majority of peri-implantitis cases are iatrogenic in nature.16
This is compounded by another trend in which implant companies and educators promote niche, complex surgical procedures with relatively limited indications as the standard of care – for example, immediate implant placement and immediate restoration or complex guided bone regeneration (GBR) techniques. These surgical procedures require thorough education, a good understanding of tissue biology, excellent surgical skills and talent, and a large enough patient pool to incrementally develop the surgical experience needed to undertake complex procedures and manage complications if they arise. In this respect, good mentoring is critical.
The question is: How can we reduce the high prevalence of peri-implantitis? The obvious solution is better training and education for dentists involved in implant therapy. Unfortunately, many dentists graduate with limited knowledge and practical experience in implant therapy.
Today, too many dentists receive implant education through privately run or short, company-based continuing education programs. These courses often focus on advanced and complex procedures without establishing a solid foundation in the fundamentals of dental implantology. This is clearly insufficient to provide the prerequisites for successful outcomes.
In the long term, the trend should move toward requiring dentists who wish to surgically place implants to undergo education through properly accredited education and training programs that provide mentoring and guidance. There are already some countries – for example, China, Singapore, France and major Middle Eastern countries – that legally restrict surgical implant placement by general dentists until they have secured official, government-approved clinical privileges through accredited postgraduate training.
In the previously mentioned publication by Chen et al. (2026),11 we proposed that early exposure of the micro-rough surface is a primary predisposing factor for peri-implantitis (Figure 1). The following causative factors and co-factors were identified:
Causative factors
1. Implant design
Implants with a micro-rough implant surface increase susceptibility to peri-implantitis when the rough surface is exposed to the sulcus. Hence, dental implants with a hybrid surface design offer the advantage of minimizing the risk of micro-rough surface exposure during healing.
In addition, placement of the micro-rough implant surface approximately 1 mm subcrestally is strongly recommended as a safety buffer. This means that, in patients with more extensive crestal bone remodeling during healing or incomplete bone regeneration at defect sites, the machined implant surface is exposed to the peri-implant sulcus.
2. Surgical risk factors
a. Implants placed into a ridge with reduced crest width (i.e., insufficient thickness of buccal and lingual bone after placement) are at risk of avascular necrosis.17-18 Avascular necrosis results in early crestal bone loss and exposure of the micro-rough implant surface to the sulcus.
b. In cases of a peri-implant bone defect, the surgeon must select an appropriate bone regeneration or bone augmentation procedure to achieve predictable bone augmentation/regeneration of the defect. Too often, poor case selection and poor surgical technique result in incomplete regeneration of the defect, leading to exposure of the microrough surface to the sulcus, which then increases the risk of peri-implantitis.
c. Implant malposition is a recognized cause of an exposed micro-rough implant surface to the sulcus.19 Malposition can occur in three dimensions: orofacially, mesiodistally and coronoapically. In addition, when multiple implants are placed, implant proximity should be avoided because this creates conditions for early crestal bone loss between the implants and will almost certainly make maintenance and home care difficult once the implants are restored. In conclusion, correct 3D implant placement is one of the key factors for implant success.
3 Prosthetic risk factors
a. The design and fit of the prosthesis can have a direct influence on the maintenance of crestal bone. With platform-switching restorations, the abutment should emerge from the implant with a relatively narrow emergence angle. Emergence angles greater than 30 to 40 degrees increase the risk of crestal bone resorption and exposure of the micro-rough implant surface.20
b. Cemented restorations should be avoided. Cement remnants are a significant cause of periimplantitis. 21
c. The fidelity of implant restorations with platform-matching restorations is of great importance because the creation of a micro- or even a macro-gap causes chronic infiltration and subsequent crestal bone loss.22
Co-factors
The following co-factors also may contribute to the development and progression of peri-implantitis when a micro-rough implant surface is exposed.
1. Patient factors
To minimize the risk of peri-implantitis, patient risk factors need to be identified and steps taken to mitigate the risk. Too often, patients are accepted for implant treatment without establishing their level of compliance and understanding of their role in maintaining peri-implant tissue health.
Patients with a history of periodontitis are well recognized as having an elevated risk of developing periimplantitis. This cohort of patients should be managed and monitored very carefully. Uncontrolled systemic factors and habits such as heavy cigarette smoking are also important considerations. In terms of anatomic risk, sites with a lack of keratinized peri-implant mucosa need to be monitored carefully. In the presence of early crestal bone loss, these sites are at risk of developing peri-implantitis.
2. Follow-up and maintenance factors
To maintain peri-implant health, a long-term commitment to supportive care is required. Tailoring maintenance care intervals and treatment interventions according to individual patient risk profiles has been shown to be effective in minimizing biological complications.23
It is important to detect crestal bone loss and changes in the peri-implant soft tissues (keratinized mucosa thickness and width) at an early stage. These early changes necessitate closer monitoring and increased recall frequencies.11
In summary, the majority of cases of peri-implantitis are initiated by surgical and/or prosthetic errors during implant therapy. We need to think of peri-implantitis as a complication of implant therapy rather than a classical disease. The transition to a complication-based model of peri-implantitis represents a paradigm shift in how it is prevented, diagnosed and clinically managed.11
Collectively, all stakeholders in implant dentistry, including clinicians, researchers, educators and implant manufacturers, share an obligation to lower the prevalence of peri-implantitis. Otherwise, the reputation of implant dentistry will be severely compromised.
See article references here.
