Early management of bone loss around implants using laser therapy: A case report

Introduction

A beautiful radiant smile is one of the greatest assets any person can have. It signifies youth, health, and happiness. Loss of a tooth in the esthetic zone compromises this and in turn has a serious social, emotional, and psychological effect on the person.¹ There are many modalities to replace the missing teeth from removable to fixed prostheses to implants (most favored). Implants provide better retention and esthetics than other modalities. With the aid of various esthetic restorations available, wonderful results can be achieved. Both the pink and white esthetics can be re-established.

When Branemark first started implant placement he advocated placement of implants 6 months post extraction in healed sockets.² Professor Wilfried Schulte from the University of Tubingen of Germany was the pioneer in immediate implant placement called Tubingen immediate implant. These implants were made of ceramic and resulted in fractures but soon titanium implants took over the market. Based on implant placement from the time of extraction, the 3^rd International team of implantology classification was given. Hammerle et al., gave four categories, which were immediate implant placement, early implant placement with soft tissue healing, early implant placement with partial bone healing, and late implant placement.³ This was incorporated in the 3rd volume of the International Team for Implantology ( ITI) guide series.⁴ 

Immediate implant placement gives the best esthetic results, but immediate implant placement has certain drawbacks. These include the increased risk of infection and associated failures if the socket is infected, the need to advance the flap to cover the implants in situations aiming for a submerged implant healing, and an increased risk for compromised esthetic outcomes. ⁵ To overcome some of these potential risks, an early implant placement protocol has been proposed, as it may share some of the advantages of immediate placement. By utilizing the socket walls before they become fully resorbed, they allow primary healing after tooth extraction. This results in achieving enough soft tissues in case of need for flap closure and reducing the risks of infection during implant placement.⁶

With healing, bone loss around the placed implant is inevitable. To diminish this process further adjuvant treatments are required. Laser-supported photodynamic therapy (PDT) focuses on infection control, detoxification of implant surfaces, regeneration of lost tissues, and plaque control regimes via mechanical debridement with or without raising a surgical flap and helping in reducing the chances of developing peri-implantitis.⁷ Implant surface decontamination and resolution of inflammation are the main objectives in the treatment of peri-implantitis. Mechanical decontamination in conjunction with tetracycline-impregnated fibers gives better results indicated by improvement in the pocket depth and bleeding on probing. In PDT, laser light of a specific wavelength with photosensitizer application stimulates photosensitizer dye molecules. This causes a change in the dye molecules from a ground singlet state to an excited triplet state that oxidizes to form highly reactive and cytotoxic singlet oxygen resulting in bacterial cell death. This results in the reduction of microbial load around the implant. ⁸

This case report presents early implant placement with adjuvant laser decontamination and local drug delivery to prevent bone loss around the implant.

Case discussion

A 32-year-old male patient reported to the Department of Prosthodontics with the chief complaint of a fractured fixed partial denture in the upper front teeth region. Clinical examination revealed fractured fixed partial dentures with 11 as the abutment and 21 as the cantilever pontic. Radiographic examination revealed an adequate alveolar bone and an absence of periapical pathology with respect to 11. A fracture line was seen on 11 below the crest of the alveolar bone and was limited to the tooth (Figure 1, Figure 2). After discussing the choices of treatment available, it was decided to extract the tooth and replace it with an endosseous implant. Early implant placement in 11 region and conventional implant placement in the 21 region was planned to avail the benefits like preservation of bone and emergence profile. Implant in the site of 11 was planned to be placed 8 days post extraction to provide time for the gingival soft tissues to heal but avoid further resorption of the residual alveolar bone and a conventional implant was planned in the region of 21. The sizes of the implants were estimated by calculations from the radiograph. The lengths were decided to be 16 mm for 11 and 13 mm for 21 region for achieving primary stability. ( Touareg^tm- S, Adin Dental Implant Systems Ltd )

The root stump was extracted atraumatically 8 days before implant placement without expanding the socket (Fig. 3). Theimplant was then placed,under 2% lignocaine with adrenaline administered as anaesthetic for the anterior superior nerve block and incisive nerve block. A full-thickness flap was raised, granulation tissue and soft tissue remnants in the socket were removed, alveolar bone curettage was performed, and implant sites were irrigated with betadine solution. The implant was placed in a standard sequential drilling procedure directly into the extraction socket. To ensure primary stability, the drilling protocol included under preparation of the implant site without screw tapping or countersinking. The implants were placed using a torque controller. An insertion torque of 50 Ncm was maintained during the placement. Reconstruction of the residual alveolar bone crest was done wherever it was deemed insufficient. The conventional implant was placed in the adjacent edentulous space parallel to the first implant and a radiograph was taken to confirm it. (Fig. 4) 

Demineralized bovine bone (BIO-OSS) was mixed with autogenous bone and covered with a guided tissue regeneration (HEALIGUIDE) membrane (Fig.5, Fig. 6). Flaps were reapproximated and sutured. Amoxicillin with clavulanic acid tablets (625 mg) twice a day for 5 days after surgery, aceclofenac 100 mg twice daily up to 3 days after surgery, and chlorhexidine 0.2% mouthwash twice daily for 2 to 3 weeks were prescribed. A post-operative periapical radiograph was taken after implant placement and one week, one month, and after 6 months. A removable partial denture was provided to the patient for the esthetic coverage till the fabrication of the permanent prosthesis.

During the second stage recall, it was found that the conventional implant suffered 2 mm crestal bone loss and the early placement implant suffered 1 mm bone loss. Therefore, to prevent further detrimental effects laser-supported PDT was planned. Mechanical debridement of the implants was done using an ultrasonic device with saline irrigation and plastic curettes (Fig. 7). Adjunctive sub-mucosal diode laser application with toluidine blue die was carried out according to the instructions of the manufacturer. Tetracycline impregnated fibers (Periodontal Plus AB) were placed in the sulcus following irrigation with chlorhexidine solution ( Fig 8, Fig. 9). The area was closed with periopack to keep the fibers in place and avoid contamination of the field for 5 days. After five days the pack was removed. Following tissue healing, (Fig.10) the implant’s healing abutments were secured on the implants. (Fig. 11) Impressions were made by closed tray technique using vinyl polyvinylsiloxane impression material and prostheses fabricated following delayed implant loading protocol ( Fig. 12).

Discussion

Early implant placement provides an advantage of initial soft and hard tissue healing without causing unfavorable bone loss, loss of keratinized mucosa, and tension-free closure with a shorter treatment period. In the anterior esthetic zone, preservation of the gingival contour and height along with the height and contour of the alveolar bone is essential for the emergence profile of the prosthesis The placement of an implant in the region of the healing socket provides for sufficient blood supply, different growth factors, and preservation of natural emergence profile.^9,10 This facilitates for faster healing and osseointegration.

Studies by Schwartz-Arad et al., (2005) and Fransson et al., (2010) have shown that bone loss of more than 1.5 mm within the 1st year was a sign of impending peri-implantitis and lead to failure of the implant.¹¹ The therapy for preventing further deterioration is through a conservative approach with a combination of scaling, local drug delivery, and PDT. Ultrasonic scaling with Teflon-coated plastic instruments has been suggested to prevent damage to the implant body.¹²

In PDT, a laser of 580 to 1400 nm wavelength produces reactive oxygen species by multiplicity with help of a high-energy, single-frequency light of diode lasers that impacts photosensitizers. Basseti et al., (2013) ¹³ found that photodynamic therapy produced bactericide effects against aerobic and anaerobic bacteria. Reducing the bacterial load reduces the susceptibility to peri-implantitis.

A review by Javed et al., (2013) ¹⁴ suggested the use of local and systemic delivery of drugs like tetracycline and doxycycline along with chlorhexidine application to reduce the amount of bone loss and pocket formation and result in higher implant adhesion.

In the above case, the bone loss around the implant placed in the 21 region was significant hence the conservative approach was considered. First ultrasonic scaling to remove the granulation tissue was carried out followed by photodynamic therapy with a soft tissue laser. The area was then irrigated with chlorhexidine solution and the sulcus around the implant was packed with tetracycline fibers to reduce the bacterial load. This resulted in a marked reduction in signs of gingival inflammation around the implant.

Following this, the porcelain fused metal prosthesis was fabricated. The impressions were made after the healing of the gingival to provide proper esthetic outcomes.

Restoration of the edentulous span in the anterior region requires proper treatment planning keeping in mind the white and pink esthetics. To provide esthetic gingival health, preservation of the underlying hard and soft tissue contour is impeccable. The combination of mechanical debridement, PDT, and placement of tetracycline fibers prevents the progression of peri-implant issues, giving the implants a longer life.

Conflict of interest

None