Treatment of Peri-Implantitis Using Nonsurgical Debridement with Bioresorbable Nanospheres for Controlled Release of Doxycycline: Case Report

Peri-implantitis is an inflammatory disease characterized by progressive supporting bone destruction.¹ It is caused mostly by bacteria, which adhere and proliferate onto implant surfaces.² Its diagnosis is developed by observing some clinical signs, such as bleeding on probing, suppuration, and progressive probing depths, as well as radiographic signs.^1,3

When dental implants are infected, the causative micro-organisms are usually those implicated in periodontal disease.² It has been observed that reducing bacterial charge in diseased areas leads to stabilization and healing of peri-implant tissues.^4-6 The use of systemic antibiotics is not indicated because most of the manifestations of peri-implantitis are local.⁷ However, the main issue with local antimicrobials concerns the lack of available alternatives worldwide, most of which present low substantivity in the affected sites, resulting in lesions not always being resolved.⁸

To solve this, new controlled-release drug systems have been developed and tested in order to offer a longer duration effect in the target area.^9-11 This case report evaluated the effect on clinical parameters of the association of nonsurgical debridement with a new controlled-release system of doxycycline by bioresorbable polymeric nanospheres.

A 42-year-old nonsmoking white woman was referred to the clinic of Periodontics at Piracicaba Dental School, São Paulo, Brazil, presenting with bleeding and suppuration symptoms on two mandibular implants. She had good oral hygiene and was otherwise in good periodontal health. Clinical examination revealed two implants replacing teeth Nos. 19 and 20. In addition to the bleeding and suppuration on probing, increased probing depths around both implants was observed (Figure 1); however, there was no mobility with either (Table 1).

After this clinical and radiographic examination, the patient was diagnosed with peri-implantitis (Figure 2). Therefore, the bridge was unscrewed and removed for better visualization of the implants, and nonsurgical debridement with a microbrush and sterile saline solution was performed under local anesthesia for 10 minutes per implant, in order to disorganize the peri-implantar biofilm (Figure 3). After debridement, 3 mg of poly(lactide-co-glycolide (PLGA) nanospheres loading doxycycline 10% was administered into the deepest peri-implantar pocket (Figure 4). The bridge was then re-placed and the patient was flagged for supportive therapy.

After 30 days, peri-implant mucosal inflammation was in remission and the patient continued to achieve good plaque control. After 15 months, it was observed that there was no bleeding nor suppuration on probing, and decreases of probing depths on both implants were observed, indicating good progress (Figure 5) (Table 1). Radiographically, no progression of bone resorption was observed around the No. 20 implant (Figure 6).

This case report shows an alternative approach for treating peri-implantitis. It presents clinical results after application of bioresorbable polymeric doxycycline 10% loading nanospheres as an adjunct to nonsurgical debridement of peri-implant pockets.

The use of antibiotics to control peri-implantitis is based on its infectious etiology.⁵ Once bacteria challenge is suppressed, peri-implant tissues may be allowed to heal, reestablishing a healthy condition.^4-6 Either systemic or local antimicrobials can be used to achieve this; however, to avoid patient overexposure to antibiotics, local antibiotic administration is more suitable for adjunctive peri-implantitis treatment because peri-implantitis often occurs locally. One limitation in the use of local antibiotics, however, is their substantivity in peri-implantar pockets. The administration of bioresorbable polymer (PLGA) nanospheres as carriers to control the release of doxycycline into peri-implantar pockets was deemed an appropriate approach to sustainable substantivity, as previous studies had reported improvements after single administration of locally delivered antibiotic in similar types of peri-implant lesions.⁴

The main objective of this approach was to suppress the microbiota.¹² The controlled release of doxycycline occurs as the nanospheres are hydrolyzed and releases the drug to act over the microbiota. This controlled release, nevertheless, can reduce anaerobic population in biofilm without resulting in a change in either the number of resistant bacteria present or the acquisition of antibiotic resistance.¹³

Based on these results, it might be concluded that this association of nonsurgical debridement and local release of doxycycline by bioresorbable nanospheres may improve clinical outcomes without needing a surgical approach, and that this approach may be used for treating some cases of peri-implantitis. The patient in this case remains in supportive therapy in order to avoid recurrence of disease, since the bridge was not changed. Further studies to replicate similar effects of this therapy, however, are warranted.

Lucas Alves Moura, DDS, MS
Department of Prosthodontics and Periodontics
Division of Periodontics
Piracicaba Dental School
State University of Campinas (UNICAMP)
Piracicaba, São Paulo, Brazil

Laboratory of Biomaterials – Pontifical Catholic University of São Paulo (PUC-SP)
Sorocaba, São Paulo, Brazil

Ana Paula Oliveira Giorgetti Bossolan, DDS, MS
Department of Prosthodontics and Periodontics
Division of Periodontics
Piracicaba Dental School
State University of Campinas (UNICAMP)
Piracicaba, São Paulo, Brazil

Eliana Ap. de Rezende Duek, PhD
Laboratory of Biomaterials – Pontifical Catholic University of São Paulo (PUC-SP)
Sorocaba, São Paulo, Brazil

Enilson Antonio Sallum, DDS, MS, PhD
Department of Prosthodontics and Periodontics
Division of Periodontics
Piracicaba Dental School
State University of Campinas (UNICAMP)
Piracicaba, São Paulo, Brazil

Francisco Humberto Nociti Jr, DDS, MS, PhD
Department of Prosthodontics and Periodontics
Division of Periodontics
Piracicaba Dental School
State University of Campinas (UNICAMP)
Piracicaba, São Paulo, Brazil

Márcio Zaffalon Casati, DDS, MS, PhD
Department of Prosthodontics and Periodontics
Division of Periodontics
Piracicaba Dental School
State University of Campinas (UNICAMP)
Piracicaba, São Paulo, Brazil

Antonio Wilson Sallum, DDS, MS, PhD
Department of Prosthodontics and Periodontics
Division of Periodontics
Piracicaba Dental School
State University of Campinas (UNICAMP)
Piracicaba, São Paulo, Brazil