Treatment options for ailing and failing implants are varied. The clinician should start conservatively and progress to more aggressive therapy. The overall goal of therapy is to establish a functional restoration and acceptable esthetics. Therefore, any therapy provided should arrest further loss of bone support and re-establish a healthy peri-implant mucosal seal. The goal of the treatment of complications and failing implants is to leave the patient with a functional restoration and acceptable esthetics. Therefore, arresting further loss of bone support and reestablishing a healthy peri-implant mucosal seal should be the goal of treatment. Attempts to eliminate osseous defects or to stimulate bone formation to regenerate lost supporting bone would be the ideal goal.
Non-Surgical Therapy
The most conservative approach to treatment involves non-surgical therapy. This treatment modality includes three subcategories:
a) Pharmacological therapy.
b) Occlusal therapy.
c) Mechanical debridement.
Pharmacological therapy for patients presenting with an ailing implant involves subgingival irrigation for 10 days to 3 weeks (2 to 3 times per 24 hour time period).This may be completed at home following careful instructions from the clinician or dental hygienist. Chlorhexidine is most often prescribed because of its antimicrobial effect and substantivity at the affected site.Other pharmacological therapies include local application of tetracycline fibers and systemic antibiotics. Bacteria associated with failing implants have been found to be sensitive to the following antibiotics: penicillin G , amoxicillin, combination of amoxicillin and metronidazole, and amoxicillin-clavulanate.Occlusal interferences may contribute to ailing and failing implants. Occlusal adjustment is necessary when premature contacts or interferences are present. The implant prosthesis also must be examined when grinding, bruxing, or other parafunctional habits are evident. The clinician must correct these occlusal errors to prevent overloading of the implant. Nightguard therapy may be indicated as well.A third non-surgical therapy recommended for treating the ailing or failing implant is mechanical debridement. Local debridement of tissues surrounding an implant using either plastic hand instruments or ultrasonic instruments with a plastic tip has been suggested. Plastic instruments are necessary to debride plaque from titanium dental implants without damaging the soft titanium surface.
Surgical Therapy
The clinician may use a surgical approach when non-surgical therapies are not indicated or are unsuccessful.The surgical techniques are modified from those used to treat bone defects around natural teeth. The type and size of the bone defect must be identified before deciding on the type of surgery. This is done with the help of Probing and Sounding under local anesthesia and radiographic evaluations are done.This forms the basis whether the implant will be removed or a resective type surgery will be done or a regenerative procedure will be undertaken.
1) Resective therapy: Is used to reduce pockets, correct negative osseou architecture and rough implant surfaces and increase the area of keratinized gingiva if needed.
Apically positioned flaps and osseous resective therapy is used to correct the horizontal bone loss and moderate vertical bone loss (<3mm) and to reduce the overall pocket depth. Let us discuss the surgical procedure now. A full thickness flap is raised to access the surgical area. Degranualution of the surgical defect is done while taking care that the metallic instrument does not contact the implant surface. Implant surface is now detoxified and prepared. . Then Surface Polishing or Implantoloplasty is carried out. It is done to arrest the progression of the disease and achieve a maintainable site for the patient. For this purpose, all implant surfaces that are smooth and clean coronal to the bone level are preferred. Therefore, surfaces with threads or roughened topography such as HA are indicated for alterations with high-speed diamond burs and polishers to produce a smooth continuous surface. Copious irrigation for cooling purposes is used while the implant topography is being modified.
It is very vital to understand that Implantoplasty is done only during resective surgery and not regenerative surgery. This is done as metal particles could interfere with the regeneration of bone tissue. Peri-implant bone defects with predominantly horizontal or one wall topographies can be treated resulting in healthy shallow pockets post surgery.
2) Regenerative therapy : Is also used to achieve the above objectives but with the ultimate goal of regeneration of lost bone tissue. Before we start discussing the procedures let us understand the types of osseus defects around implants. They are classified into four main groups.
Group I defects: These demonstrate moderate horizontal bone loss with a minimal intrabony component. This group of implants is usually covered by a thin buccal/lingual bone crest at the time of placement and are at an early stage of periimplant breakdown.
Group II defects Present moderate to severe horizontal bone loss with a minimum intrabony component. Its an advanced version of Group I.
Group III defects Demonstrate minimal to moderate horizontal bone loss with an advanced circumferential intra bony lesion. These implants are initially covered by a thin coronal bone crest and a wider apical bone base. Frequently the pattern of bone loss has a symmetric feature with a circular trough of uniform width and depth occurring around the circumference of the implant.
Group IV Presents more complicated implant defects with moderate horizontal bone loss with an advanced circumferential intrabony lesion; additionally the buccal and/or lingual bone plate has been lost.To achieve regeneration of lost bone Guided Bone Regeneration and Grafting techniques have been suggested. However regeneration of bone is enhanced if the area is isolated from the oral environment. Therefore it is recommended to remove the implant prosthesis 4 to 8 weeks prior to the regenerative surgical procedure to allow compliance with the oral hygiene procedures and the soft tissue to collapse and heal over the implant site with a cover screw in place.
Thus at the time of regenerative surgery a midcrestal incision can be made over intact tissue and full thickness flap is raised. If removal of prosthesis is not possible before hand then a sulcular incision is made to raise the flap.
a) The first step in surgical therapy is to reflect the tissue and degranulate the defect.
b) It is followed by exposing and treating the bacterially contaminated implant surface. The clinician must remove endotoxins from the surface of the failing implant. This is especially true of hydroxyapatite (HA) coated surfaces. The HA coating may be pitted, cracked, and brownish in color and may show areas of resorption down to the base metallic substrate). These surface changes result from the infectious aspects of disease and inflammation. As the pH in the area becomes lower during inflammation, the HA surface begins to decalcify and/or resorb. This resorption process is similar to the effects of periodontal disease, as the implant exhibits the subsequent loss of connective tissue attachment and establishes an osseous defect. It is important in an infected implant with HA surface that is deteriorating that the coating be removed by using an ultrasonic scaler as the use of hand curettes is slow and the air abrasives are associated with the danger of air emboli in marrow spaces.
c) The literature suggests using chemical agents to detoxify the surface of the failing implant. The rationale for their use is the subgingival flora associated with dental implants have been shown to be very similar to those associated with natural teeth. Chemotherapeutic agents such as chlorhexidine gluconate, stannous fluoride, and tetracycline are antimicrobials and/or antibiotics, which theoretically would not only kill the periodontopathic bacteria but also would remove endotoxins from a root implant surface. Some of these agents appear to be more effective than others. Studies have concluded that detoxification of the implant surface using citric acid is most beneficial. Prepare a supersaturated solution of citric acid ( pH 1 - crystals mixed in sterile water) and apply with cotton pledget or camel's hair brush for 30 seconds per surface.
d) Once the implant is decontaminated, the next step is to regenerate or obliterate the osseous defect with a grafting material. Graft with freeze dried bone if completely detoxified or graft with an alloplast if not completely detoxified. The decision to utilize an alloplast or an allograft depends on the effectiveness of the detoxification of the implant surface. If the surface is clean and detoxified,with all exposed areas of the implant visualized and instrumented, it is possible to graft with an allograft material such as DFDBA to achieve biologic healing.However, if the implant surface cannot be cleaned and detoxified (due to vents, holes in the implant fixture, or tortuous osseous defects not accessible to instrumentation), it is advisable to graft with an alloplast material such as HA (particulate form), HTR, or Bioactive Glass. Alloplasts provide a physical, biocompatible "fill," minimize probing depth, support the mucoperiosteal flap, and help prevent further epithelial invagination.
e) In conjunction with the various grafts discussed for bone regeneration around failing implants, clinicians also may use membranes to keep these grafts in the desired location. Resorbable membranes are most commonly used today. Non- resorbable membranes are less commonly used because of the requirement for an additional surgery to recover the intact membrane. It is important that the membrane extends 3-4 mm beyond the surgical defect and secured.
f) The flap should be closed in primary closure with mattress and interrupted sutures without tension. Leave the implant out of function and "covered" for 10-12 weeks. After the healing is complete the abutment can be reattached after a stage 2 type surgery.In case there is no active infection present and the bone loss is due to overload the treatment procedure remains same except the HA coating of the implant should not be removed but the detoxification should be done only for 30 seconds as it tends to remove the coating. Also tetracycline should not be used on intact HA as it changes the calcium phosphate ratio and will affect the healing dynamics.
In case of one stage implants being treated or when the prosthesis has to be maintained a Pergingival Regenerative Therapy is done. The membrane is perforated with a 3 mm hole and slid over the implant. The membrane should ensure complete coverage and isolation of the vertical bone defect. The flap is then sutured closely to the implant neck. It is very vital to remove the membrane after 6-8 weeks after surgery. This is necessary as there is no primary closure there is accumulation of plaque on the membrane and there is potential risk of infection of the membrane and the peri-implant site.
Cumulative Interceptive Supportive Therapy (ITI Consensus report)
Systematic and continuous monitoring of the periimplant tissue conditions is recommended for the diagnosis of peri-implant health and disease. The parameters that are recommended to assess the presence and severity of diseases include:
Non-Surgical Therapy
The most conservative approach to treatment involves non-surgical therapy. This treatment modality includes three subcategories:
a) Pharmacological therapy.
b) Occlusal therapy.
c) Mechanical debridement.
Pharmacological therapy for patients presenting with an ailing implant involves subgingival irrigation for 10 days to 3 weeks (2 to 3 times per 24 hour time period).This may be completed at home following careful instructions from the clinician or dental hygienist. Chlorhexidine is most often prescribed because of its antimicrobial effect and substantivity at the affected site.Other pharmacological therapies include local application of tetracycline fibers and systemic antibiotics. Bacteria associated with failing implants have been found to be sensitive to the following antibiotics: penicillin G , amoxicillin, combination of amoxicillin and metronidazole, and amoxicillin-clavulanate.Occlusal interferences may contribute to ailing and failing implants. Occlusal adjustment is necessary when premature contacts or interferences are present. The implant prosthesis also must be examined when grinding, bruxing, or other parafunctional habits are evident. The clinician must correct these occlusal errors to prevent overloading of the implant. Nightguard therapy may be indicated as well.A third non-surgical therapy recommended for treating the ailing or failing implant is mechanical debridement. Local debridement of tissues surrounding an implant using either plastic hand instruments or ultrasonic instruments with a plastic tip has been suggested. Plastic instruments are necessary to debride plaque from titanium dental implants without damaging the soft titanium surface.
Surgical Therapy
The clinician may use a surgical approach when non-surgical therapies are not indicated or are unsuccessful.The surgical techniques are modified from those used to treat bone defects around natural teeth. The type and size of the bone defect must be identified before deciding on the type of surgery. This is done with the help of Probing and Sounding under local anesthesia and radiographic evaluations are done.This forms the basis whether the implant will be removed or a resective type surgery will be done or a regenerative procedure will be undertaken.
1) Resective therapy: Is used to reduce pockets, correct negative osseou architecture and rough implant surfaces and increase the area of keratinized gingiva if needed.
Apically positioned flaps and osseous resective therapy is used to correct the horizontal bone loss and moderate vertical bone loss (<3mm) and to reduce the overall pocket depth. Let us discuss the surgical procedure now. A full thickness flap is raised to access the surgical area. Degranualution of the surgical defect is done while taking care that the metallic instrument does not contact the implant surface. Implant surface is now detoxified and prepared. . Then Surface Polishing or Implantoloplasty is carried out. It is done to arrest the progression of the disease and achieve a maintainable site for the patient. For this purpose, all implant surfaces that are smooth and clean coronal to the bone level are preferred. Therefore, surfaces with threads or roughened topography such as HA are indicated for alterations with high-speed diamond burs and polishers to produce a smooth continuous surface. Copious irrigation for cooling purposes is used while the implant topography is being modified.
It is very vital to understand that Implantoplasty is done only during resective surgery and not regenerative surgery. This is done as metal particles could interfere with the regeneration of bone tissue. Peri-implant bone defects with predominantly horizontal or one wall topographies can be treated resulting in healthy shallow pockets post surgery.
2) Regenerative therapy : Is also used to achieve the above objectives but with the ultimate goal of regeneration of lost bone tissue. Before we start discussing the procedures let us understand the types of osseus defects around implants. They are classified into four main groups.
Group I defects: These demonstrate moderate horizontal bone loss with a minimal intrabony component. This group of implants is usually covered by a thin buccal/lingual bone crest at the time of placement and are at an early stage of periimplant breakdown.
Group II defects Present moderate to severe horizontal bone loss with a minimum intrabony component. Its an advanced version of Group I.
Group III defects Demonstrate minimal to moderate horizontal bone loss with an advanced circumferential intra bony lesion. These implants are initially covered by a thin coronal bone crest and a wider apical bone base. Frequently the pattern of bone loss has a symmetric feature with a circular trough of uniform width and depth occurring around the circumference of the implant.
Group IV Presents more complicated implant defects with moderate horizontal bone loss with an advanced circumferential intrabony lesion; additionally the buccal and/or lingual bone plate has been lost.To achieve regeneration of lost bone Guided Bone Regeneration and Grafting techniques have been suggested. However regeneration of bone is enhanced if the area is isolated from the oral environment. Therefore it is recommended to remove the implant prosthesis 4 to 8 weeks prior to the regenerative surgical procedure to allow compliance with the oral hygiene procedures and the soft tissue to collapse and heal over the implant site with a cover screw in place.
Thus at the time of regenerative surgery a midcrestal incision can be made over intact tissue and full thickness flap is raised. If removal of prosthesis is not possible before hand then a sulcular incision is made to raise the flap.
a) The first step in surgical therapy is to reflect the tissue and degranulate the defect.
b) It is followed by exposing and treating the bacterially contaminated implant surface. The clinician must remove endotoxins from the surface of the failing implant. This is especially true of hydroxyapatite (HA) coated surfaces. The HA coating may be pitted, cracked, and brownish in color and may show areas of resorption down to the base metallic substrate). These surface changes result from the infectious aspects of disease and inflammation. As the pH in the area becomes lower during inflammation, the HA surface begins to decalcify and/or resorb. This resorption process is similar to the effects of periodontal disease, as the implant exhibits the subsequent loss of connective tissue attachment and establishes an osseous defect. It is important in an infected implant with HA surface that is deteriorating that the coating be removed by using an ultrasonic scaler as the use of hand curettes is slow and the air abrasives are associated with the danger of air emboli in marrow spaces.
c) The literature suggests using chemical agents to detoxify the surface of the failing implant. The rationale for their use is the subgingival flora associated with dental implants have been shown to be very similar to those associated with natural teeth. Chemotherapeutic agents such as chlorhexidine gluconate, stannous fluoride, and tetracycline are antimicrobials and/or antibiotics, which theoretically would not only kill the periodontopathic bacteria but also would remove endotoxins from a root implant surface. Some of these agents appear to be more effective than others. Studies have concluded that detoxification of the implant surface using citric acid is most beneficial. Prepare a supersaturated solution of citric acid ( pH 1 - crystals mixed in sterile water) and apply with cotton pledget or camel's hair brush for 30 seconds per surface.
d) Once the implant is decontaminated, the next step is to regenerate or obliterate the osseous defect with a grafting material. Graft with freeze dried bone if completely detoxified or graft with an alloplast if not completely detoxified. The decision to utilize an alloplast or an allograft depends on the effectiveness of the detoxification of the implant surface. If the surface is clean and detoxified,with all exposed areas of the implant visualized and instrumented, it is possible to graft with an allograft material such as DFDBA to achieve biologic healing.However, if the implant surface cannot be cleaned and detoxified (due to vents, holes in the implant fixture, or tortuous osseous defects not accessible to instrumentation), it is advisable to graft with an alloplast material such as HA (particulate form), HTR, or Bioactive Glass. Alloplasts provide a physical, biocompatible "fill," minimize probing depth, support the mucoperiosteal flap, and help prevent further epithelial invagination.
e) In conjunction with the various grafts discussed for bone regeneration around failing implants, clinicians also may use membranes to keep these grafts in the desired location. Resorbable membranes are most commonly used today. Non- resorbable membranes are less commonly used because of the requirement for an additional surgery to recover the intact membrane. It is important that the membrane extends 3-4 mm beyond the surgical defect and secured.
f) The flap should be closed in primary closure with mattress and interrupted sutures without tension. Leave the implant out of function and "covered" for 10-12 weeks. After the healing is complete the abutment can be reattached after a stage 2 type surgery.In case there is no active infection present and the bone loss is due to overload the treatment procedure remains same except the HA coating of the implant should not be removed but the detoxification should be done only for 30 seconds as it tends to remove the coating. Also tetracycline should not be used on intact HA as it changes the calcium phosphate ratio and will affect the healing dynamics.
In case of one stage implants being treated or when the prosthesis has to be maintained a Pergingival Regenerative Therapy is done. The membrane is perforated with a 3 mm hole and slid over the implant. The membrane should ensure complete coverage and isolation of the vertical bone defect. The flap is then sutured closely to the implant neck. It is very vital to remove the membrane after 6-8 weeks after surgery. This is necessary as there is no primary closure there is accumulation of plaque on the membrane and there is potential risk of infection of the membrane and the peri-implant site.
Cumulative Interceptive Supportive Therapy (ITI Consensus report)
Systematic and continuous monitoring of the periimplant tissue conditions is recommended for the diagnosis of peri-implant health and disease. The parameters that are recommended to assess the presence and severity of diseases include:
- Presence of plaque and calculus.
- Peri implant Probing Depth [PD].
- Presence of Bleeding on Probing [BOP].
- Presence of Suppuration.
- Radiographic evaluation.
Depending on the clinical and eventually the radiographic diagnosis, protocols for preventive and therapeutic measures have been recommended to intercept the development of peri implant lesions. This system js cumulative in nature and includes four steps which should not be used as single procedures , but rather as a sequence of therapeutic procedures with increasing anti infective potential depending on the severity and extent of the lesion. Diagnosis, therefore represents a key feature of this supportive program as per the earlier discussed parameters. Oral implants without plaque and calculus and surrounded by healthy peri-implant tissues as evidenced by absence of Bleeding on Probing (BOP), absence of suppuration and probing depth (PD) not exceeding 3 mm should be considered clinically stable and require no treatment.
The protocol includes four treatment modalities:
A = Mechanical Debridement
In this the patients are re-instructed in oral hygiene and motivated to initiate and continue maintenance. Mechanical debridement is done using non metallic curettes, and polishing is done with rubber cup and non abrasive polishing paste.
B = Chemical Plaque control (anti septic cleaning) is performed
a) Chlorhexidine gluconate is used typically as mouthrinses with 0.1 per cent to 0.2 per cent chlorhexidine for 30 seconds using approximately 10 ml.
b) Application of local chlorhexidine gel (0.2 per cent)
c) Local irrigation with chlorhexidine (0.2 per cent) two times a day for 3-4 weeks
C = Systemic or Local Antibiotic Therapy
Systemic treatment Includes:
Ornidazole (1000 mg X 1) or Metronidazole (250 mg X 3) for 10 days OR acombination of Amoxicillin (375 mg X 3 ) and Metronidazole (250 mg X 3) for 10 days.
Local Antibiotic treatment:
Local application of antibiotics using a controlled release device for 10 days. eg.,Tetracycline fibres and Minocycline Microspheres.
D = Surgical Therapy
Surgical therapy for peri-implantitis should be performed in conjunction with systemic antibiotics and implant surface decontamination. If regenerative treatment is chosen, a barrier membrane technique alone or in combination with autogenous grafts and/ or bone substitutes may be considered. Resective surgery may be considered when the periimplant defect is not suitable for regenerative techniques.This flow chart is self explanatory and is depicts the treatment planning based on the diagnostic parameters.
The protocol includes four treatment modalities:
A = Mechanical Debridement
In this the patients are re-instructed in oral hygiene and motivated to initiate and continue maintenance. Mechanical debridement is done using non metallic curettes, and polishing is done with rubber cup and non abrasive polishing paste.
B = Chemical Plaque control (anti septic cleaning) is performed
a) Chlorhexidine gluconate is used typically as mouthrinses with 0.1 per cent to 0.2 per cent chlorhexidine for 30 seconds using approximately 10 ml.
b) Application of local chlorhexidine gel (0.2 per cent)
c) Local irrigation with chlorhexidine (0.2 per cent) two times a day for 3-4 weeks
C = Systemic or Local Antibiotic Therapy
Systemic treatment Includes:
Ornidazole (1000 mg X 1) or Metronidazole (250 mg X 3) for 10 days OR acombination of Amoxicillin (375 mg X 3 ) and Metronidazole (250 mg X 3) for 10 days.
Local Antibiotic treatment:
Local application of antibiotics using a controlled release device for 10 days. eg.,Tetracycline fibres and Minocycline Microspheres.
D = Surgical Therapy
Surgical therapy for peri-implantitis should be performed in conjunction with systemic antibiotics and implant surface decontamination. If regenerative treatment is chosen, a barrier membrane technique alone or in combination with autogenous grafts and/ or bone substitutes may be considered. Resective surgery may be considered when the periimplant defect is not suitable for regenerative techniques.This flow chart is self explanatory and is depicts the treatment planning based on the diagnostic parameters.
This flow chart is self explanatory and is depicts the treatment planning based on the diagnostic parameters.
Indications of Implant Removal
Failed Implants need to be removed and the specific indications include
Severe Periimplant bone loss (> 50 per cent of implant length).
- Mobile Implant.
- Bone Loss involving the implant vents or holes- unfavourable advanced bone defect (one wall).
- Rapid Severe bone destruction within 1 year of loading.
- Non surgical or surgical therapy ineffective.
- Aesthetic area precluding the implant surface exposure.
After the implants are removed, the ridge defects can be reconstructed using bone grafts and membrane techniques. This treatment can allow the subsequent placement of a new implant.
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