Squamous cell carcinoma and dental implants: A systematic review of case reports

Titanium corrosion products from dental implants and their effect on cells and cytokine release: A review

INTRODUCTION

Titanium is considered to be an inert material owing to the ability of the material to form a passive titanium oxide layer. However, once the titanium oxide layer is lost, it can lead to exposure of the underlying titanium substructure and can undergo corrosion.

SUMMARY

The article explores the role of titanium ions and particles from dental implants on cells, cytokine release, and on the systemic redistribution of these particles as well as theories proposed to elucidate the effects of these particles on peri-implant inflammation based on evidence from in-vitro, human, and animal studies. Titanium particles and ions have a pro-inflammatory and cytotoxic effect on cells and promote the release of pro-inflammatory mediators like cytokines. Three theories to explain etiopathogenesis have been proposed, one based on microbial dysbiosis, the second based on titanium particles and ions and the third based on a synergistic effect between microbiome and titanium particles on the host.

CONCLUSION

There is clear evidence from in-vitro and limited human and animal studies that titanium particles released from dental implants have a detrimental effect on cells directly and through the release of pro-inflammatory cytokines. Future clinical and translational studies are required to clarify the role of titanium particles and ions in peri-implant inflammation and the etiopathogenesis of peri-implantitis.

Breast Implants and the Risk of Squamous Cell Carcinoma of the Breast: A Systematic Literature Review and Epidemiologic Study

Squamous cell carcinoma may arise primarily from the breast parenchyma (PSCCB) or from the periprosthetic capsule in patients with breast implants (breast implant-associated squamous cell carcinoma [BIA-SCC]). A systematic literature review was performed to identify all PSCCB and BIA-SCC cases, and to estimate prevalence, incidence rate (IR), and risk. Studies up to November 2023 were searched on PubMed, Web of Science, Google Scholar, and Cochrane Library for predefined keywords. The numerator for PSCCB and BIA-SCC was the number of cases obtained from the literature; the denominator for PSCCB was the female population aged from 18 to 99, and the denominator for BIA-SCC was the population with breast implants. Overall, 219 papers were included, featuring 2250 PSCCB and 30 BIA-SCC cases. PSCCB prevalence was 2.0 per 100,000 (95% CI, 0.2:100,000 to 7.2:100,000) individuals, with a lifetime risk of 1:49,509 (95% CI, 0.2:10,000 to 5.6:10,000); and BIA-SCC prevalence was 0.61 per 100,000 (95% CI, 0.2:100,000 to 1.3:100,000), with a lifetime risk of 1:164,884 (95% CI, 0.2:100,000 to 5.6:100,000). The prevalence of BIA-SCC is 3.33 times lower than that of PSCCB, while the prevalence of breast implant-associated anaplastic large cell lymphoma (BIA-ALCL) is 3.84 times higher than that of primary breast ALCL. When comparing the BIA-SCC prevalence of 1:164,910 individuals with breast implants regardless of texture to the BIA-ALCL prevalence of 1:914 patients with textured implants, the BIA-SCC risk is 180 times lower than the BIA-ALCL risk. BIA-SCC occurs less frequently than PSCCB and considerably less than BIA-ALCL. The association between textured implants and BIA-SCC cases is relevant for patient education regarding uncommon and rare risks associated with breast implants, and ongoing vigilance, research, and strengthened reporting systems remain imperative.

Oral Squamous Cell Carcinoma Mimicking Lichenoid Reaction After Implant Placement: A Case Report

The early detection of oral squamous cell carcinoma (OSCC) poses significant challenges, especially if it mimics a benign condition. This report presents a case of a 79-year-old nonsmoker Saudi male patient with an alveolar lesion that initially resembled an implant-induced reaction but upon biopsy revealed dysplastic squamous epithelium indicative of squamous cell carcinoma (SCC). This case highlights that lesion mimicry, the absence of pain, and low cancer awareness can cause diagnostic delays. Treatment options for OSCC include surgery, chemotherapy, and radiotherapy, with surgery being the primary treatment modality. This case emphasizes the need for heightened vigilance among healthcare providers, regular follow-ups, and enhanced cancer awareness to promote early detection and intervention. Recognizing the diverse clinical presentations of OSCC remains essential for effective management and improved patient outcomes, despite the complexities of its etiology and diagnostic challenges.

The evaluation of the delayed swollen breast in patients with a history of breast implants

Breast implants, whether placed for reconstructive or cosmetic purposes, are rarely lifetime devices. Rupture, resulting from compromised implant shell integrity, and capsular contracture caused by constriction of the specialized scar tissue that normally forms around breast implants, have long been recognized, and remain the leading causes of implant failure. It is apparent, however, that women with breast implants may also experience delayed breast swelling due to a range of etiologic factors. While a majority of delayed seromas associated with breast implants have a benign etiology, this presentation cannot be ignored without an adequate workup as malignancies such as breast implant associated anaplastic large cell lymphoma (BIA-ALCL), breast implant associated diffuse large B-cell lymphoma (BIA-DLBCL), and breast implant associated squamous cell carcinoma (BIA-SCC) can have a similar clinical presentation. Since these malignancies occur with sufficient frequency, and with sometimes lethal consequences, their existence must be recognized, and an appropriate diagnostic approach implemented. A multidisciplinary team that involves a plastic surgeon, radiologist, pathologist, and, as required, surgical and medical oncologists can expedite judicious care. Herein we review and further characterize conditions that can lead to delayed swelling around breast implants.

Squamous cell carcinoma around a subperiosteal implant in the maxilla and the association of chronic mechanical irritation and peri-implantitis: a case report

Background

As carcinogenic risk factors, environmental factors can be classified into physical, biological, and chemical factors. Subperiosteal implants (SIs) are associated with complications, such as framework exposure, infection, and fistula formation. A current hypothesis suggests that chronic mechanical irritation could be a co-factor in carcinogenesis, while peri-implantitis might be an initiating or promoting agent in the development of oral mucosal cancer. Herein, we report a case of squamous cell carcinoma (SCC) around a maxillary SI associated with chronic mechanical irritation and peri-implantitis as physical and biological factors, respectively.

Case presentation

A 74-year-old male patient presented with severe mobility of the SI and an undermined ulcer with induration, accompanied by a palatal fistula and the exposure of the metal framework. The SI had been placed on the maxilla for the occlusal reconstruction of the molar area 20 years ago. An incisional biopsy of the ulcer revealed SCC (cT4aN2cM0). Neoadjuvant chemotherapy was initiated, followed by bilateral neck dissection and partial resection of the maxilla with SI removal. Energy-dispersive X-ray analysis suggested that the SI was fabricated using pure titanium, and titanium was absent in the specimen. Scanning electron microscopy of the SI in contact with the SCC showed a few microcracks, suggesting pitting corrosion.

Discussion

Chronic mechanical irritation due to the mobility of an improperly designed SI can be a physical factor, and prolonged peri-implantitis without regular maintenance can be a biological factor in carcinogenesis. Improperly designed main struts and a large masticatory force in the molar area resulted in deterioration of the retention and mobility of the SI. The screw and framework frequently moved on mastication and came in direct contact with the ulcer as chronic mechanical irritation. Bacterial invasion into the subperiosteal space expanded by the mobility of the metal framework led to peri-implantitis. The influence of chemical factors was considered relatively small in this case since the patient had no history of smoking or drinking, and titanium was absent in the specimen. Therefore, it is conceivable that SCC can arise owing to persistent inflammation caused by chronic mechanical irritation and peri-implantitis as physical and biological factors, respectively.

Lack of association between dental implants and oral squamous cell carcinoma

Design A systematic review of the literature to identify and evaluate the epidemiologic profile, and screen for possible risk factors and spectrum of clinical characteristics of oral squamous cell carcinoma (OSCC) surrounding dental implants, was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement guidelines.Data sources A search of two databases, Medline and CENTRAL, was undertaken, limited to articles published in English from the oldest records until 10 July 2018. Google Scholar was the grey literature searched. The references list in the included articles was assessed for further inclusion suitability.Study selection Participants included patients diagnosed with OSCC surrounding dental implants. The comparator or control was patients diagnosed with OSCC without dental implants. The outcome was epidemiology and carcinogenesis. The considered study designs were case reports, case series and retrospective studies. Article selection was performed by screening titles and abstracts individually by two blind review authors using the Rayyan platform based on the inclusion criteria. Then, the full text of the selected articles was assessed to identify the eligible articles, and the reasons for exclusion were reported. When a consensus was not achieved between the review authors, a third review author, who acted as a tiebreaker, was consulted.Data extraction Two independent review authors extracted the data using a specific extraction form in Microsoft Office Excel (Microsoft Corporation, Redmond, WA, USA). The extraction form consisted of authors, publication year, country, study design, number of cases, age, sex, risk factors, region of interest, the clinical aspect of the lesion, radiographic findings, the period between implant placement and tumour diagnosis, treatment, and follow-up. The time reported in the studies was converted to months for comparison. A third review author validated the accuracy of the information collected.Synthesis Two independent review authors assessed the risk of bias by applying the Joanna Briggs Institute (JBI) Critical Appraisal Checklist (CAP) for Case Reports and the JBI CAP for Prevalence Studies (for example, retrospective studies). Disagreements were resolved by consulting a third co-author. The Grading of Recommendation, Assessment, Development and Evaluation (GRADE) tool evaluated the certainty of the evidence of the main outcomes. A PRISMA flow diagram was presented, and a table summary of descriptive characteristics of the 33 included studies. Among the figures available, bar graphs represented the 'clinical features' according to the previous history of oral potentially malignant disorders and regarding the malignancy of oral potentially malignant disorders. In addition, a stacked line with markers represented the sex of the number of cases, displaying the time until diagnosis after implant placement and the time to disease progression.Data analysis A qualitative synthesis was provided. No quantitative data synthesis nor inter-rater agreement assessment was conducted.Results Thirty-one case reports and two retrospective studies, published between 1983 and 2020, met the eligibility criteria. The total sample consisted of 63 patients (male = 44.5%) with an average of 66.7 years (range = 42 to 90 years). Oral potentially malignant disorders were found in 29 patients (46%), of which 65.5% were female patients. The most common lesions were oral lichen planus and leukoplakia in female patients (52.6% and 31.5%) and male patients (20% and 60%). In 25 patients (39.6%), there was information missing about the presence of potentially malignant oral disorders, and oral hygiene status was reported in only 17.4% of the cases. Fifty-six patients (88.8%) of OSCC with dental implants were located in the mandible, and the most common clinical presentations of OSCC with implants were exophytic mass (46%) and ulceration (36.5%). Peri-implant bone loss assessment was performed in 51 patients (80.9%), of which 44 (86.2%) had peri-implant bone loss. Thus, most of these lesions were originally treated as peri-implantitis.Conclusions Most patients with OSCC next to their dental implants were female patients lacking known risk factors, and the common location was the mandible with an exophytic mass or ulceration presentation. A major concern is that the clinical and radiographic features of OSCC could be misdiagnosed as peri-implantitis. Thus, OSCC should be considered in persistent lesions surrounding dental implants. Several of the included reports were missing previous medical history and follow-up information. Hence, better case series and studies are required to support or reject the notion of an association between dental implants and OSCC.

Primary peri-implant oral intra-epithelial neoplasia/carcinoma in situ: a case report considering risk factors for carcinogenesis

BACKGROUND

Major risk factors for oral squamous cell carcinoma (SCC) are tobacco smoking, a betel quid chewing habit, and heavy alcohol consumption. However, around 15% of oral SCCs cannot be explained by these risk factors. Although oral SCC associated with dental implants is quite rare, there has been a recent gradual accumulation of reports about it. Here, we report a case of primary peri-implant oral intra-epithelial neoplasia/carcinoma in situ (OIN/CIS) in a woman without the major risk factors for oral SCC.

CASE PRESENTATION

A 65-year-old woman was referred to our clinic with a tumor in the right lower gingiva. She had no history of tobacco smoking and only drank socially. Ten years previously, mandibular right posterior teeth had been replaced with an implant-supported porcelain-fused-to-metal restoration in a dental clinic. About 7 years later, she noticed swelling on the lingual side of the gingiva around the implant-supported restoration, and was eventually referred to our clinic with the suspicion of a neoplasia around the dental implant. The upper part of the implant body was exposed on the implant corresponding to the first molar of the right side of the mandible; this was associated with painless, elastic soft, and relatively well circumscribed gingival swelling on the lingual site. A panoramic radiograph showed slight vertical bone resorption around the implants. An incisional biopsy was conducted under the suspicion of neoplasia. Pathological microscopic examination of the biopsy specimen revealed thickened squamous epithelia with slight nuclear atypism and disorders of the epithelial rete pegs. Immunohistochemical findings showed positive staining for keratin 17 and a negative staining mosaic pattern for keratin 13. High p53, p63, and Ki-67 reactivity was also observed. From these findings, OIN/CIS of the gingiva was pathologically diagnosed, and a wide local excision with rim resection of the mandible, including the implants, was performed. The pathological findings for the resected specimen were same as those for the biopsy specimen. After 1 year of follow-up, there was no evidence of recurrence.

CONCLUSION

In this case, prolonged peri-implant mucositis or peri-implantitis may have been a plausible risk factor for carcinogenesis.