Failures in implantology
Introduction :
Despite the high success rates and stability of dental implants, failures do occur. While surgical trauma and bone volume and quality are generally considered the most important etiological factors for early implant failure, the etiology of late failures is more controversial.
Early detection and treatment of early progressive bone loss around dental implants by mechanical debridement, antimicrobial therapy and regenerative therapy are the keys to salvage early implant failure.
1. Criteria for evaluating implementation success:
According to the American Academy of Periodontology 2003:
– Absence of persistent signs/symptoms such as pain, infection, neuropathies, paresthesias and violation of vital structures
– Immobility of the implant
– No continuous peri-implant radiolucency
– Negligible progressive bone loss (less than 0.2 mm per year) after physiological remodeling during the first year of operation
– Patient/dentist satisfaction with implant-supported restoration
According to Bartolucci and Mangano:
Implant success depends on:
– Good hygiene
– Implantation and high-performance surgery
– Prosthesis adapted to balanced occlusion
– Favorable local and general conditions. TABLE 1. Criteria for assessing the success of TABLE 1. Criteria for assessing the success of
2. Difference in failure and complication:
Failures = removal of the implant but also aesthetic or functional failures.
Complications = appearance of a new morbid phenomenon during an illness or injury, often temporary and reversible.
3. Risk factors for dental implant failure:
3.1. Practitioner-related factors:
Preoperative: planning error…
Intraoperative: It is estimated that approximately 3.6% of implant failures are related to surgical trauma, also, thermal bone necrosis is a rare phenomenon and one of the causes of early implant failure.
Post-operative: Poor crown design and guidance contribute to failure.
3.2. Implant-related factors:
Dental implant materials and surface characteristics:
Most dental materials currently used clinically are quite biocompatible in human tissues in their specific dental application. They are usually made of titanium, titanium-aluminum vanadium (Ti-6Al-4V), cobalt-chromium-molybdenum, and more rarely other alloys. The most common type of failure is due to poor treatment planning and/or poor surgical execution. The incidence of this type of failure has been estimated at 10%.
3.3. Patient-related factors :
Local factors:
3.3.1. Bone quality and quantity: The most important local factor for the success of implant treatment is bone quality and quantity.
Jaffin and Berman,17 in their 5-year analysis, reported that 35% of implant failures occurred in type IV bone
3.3.2. Irradiated bone : Although radiotherapy is not an absolute contraindication to implant treatment, the success rate is only approximately 70%.
3.3.3. Biomechanical loading of occlusion :
High mechanical load leads to bone resorption. Osteocytes increase the secretion of collagenase-1 [matrix metalloproteinase-1 (MMP-1)] under mechanical load, which can trigger bone resorption. MMP-1 degrades bone collagen types I and III, the main structural collagens of bone.
Smoking as a risk factor for implant failure
The success rate of dental implants is twice as high in non-smokers as in smokers. The maxillary implant is the most affected.
Parafunctional habits and bruxism
Parafunctional habits are also linked to increased peri-implant bone loss.
Systemic factors
Systemic factors affect both bone quality and quantity. These systemic factors include poorly controlled diabetes, osteoporosis, osteomalacia, radiation, certain ongoing medications, and other conditions.
Diabetes mellitus
Diabetes mellitus has also been considered a risk factor and sometimes even a contraindication for dental implants. Recently, dental implants in diabetics have been reported to be successful, at least in the short term.
Osteoporosis
Implants in patients with osteoporosis have shown good short-term results, but long-term results have not been reported.
Medications and radiotherapy
Some medications used clinically cause bone loss, particularly glucocorticosteroids. Other medications containing chemotherapy agents, such as doxorubicin and methamphetamine, such as doxorubicin and methotrexate, inhibit osteoblasts and decrease bone formation. Radiation had no effect on the short-term success rate of implants.
Age
Theoretically, older patients will have systemic health problems, but there is no scientific evidence correlating advanced age with implant failure.
4. Implant failures:
Failures can be classified into different stages:
– preparation of the treatment plan
– surgical phase
– healing phase
– prosthetic phase
– putting the implant into operation.
- Failures and complications initiated during treatment preparation:
These are errors related to an incomplete history of bruxomania, a systemic disease (bone metabolism disease, uncontrolled diabetes) or an unexpected rare disease.
- Failures and complications initiated during the surgical phase
These are objective failures.
Preparation for the procedure and a precise, atraumatic, and tissue-preserving surgical technique are of the utmost importance.
Mandibular canal rupture
The risk of damage to the inferior dental nerve must be constantly kept in mind, which is why a safety distance of 2 mm above the mandibular canal is introduced. If intrusion is detected, the implant positioning must be corrected immediately.
Heating of the bone during drilling:
Too high a temperature rise above 47° degrees for 1 minute causes fibrous encapsulation at the bone-implant interface.
Excessive compression of the bone,
Lack of asepsis during surgery,
Primary stability defect:
Over-drilling of the implant site decreases primary stability.
Incomplete screwing of a cover screw or healing abutment
This event may have no consequences, but it may also cause tissue necrosis or local infection.
Undetected fenestrations or dehiscences:
The bone defect itself is not a problem if it is detected during placement because different techniques are available to fill the bone deficiency (bone grafting, guided bone regeneration). On the other hand, if it has not been identified, it can lead to fibrous encapsulation.
Implant malposition:
The implant is placed in a position dictated by the presence of available bone and not by prosthetic needs. It can be osseointegrated but does not meet aesthetic requirements, the position is too mesial, too distal, too vestibular or too palatal in relation to the axis of the rehabilitated tooth.
4.3. Failures and complications initiated during the healing phase
These objective failures are also one of the causes of primary failures.
Uncontrolled forces exerted on the implant
This can occur when compulsive repeated pressure is applied with the tongue or when hard food is introduced too quickly after surgery.
Infection
The first stage, mucositis, is reversible; it does not affect the bone surrounding the implant. However, peri-implantitis leads to bone loss.
4.4. Failures and complications initiated during the prosthetic phase
At the end of the healing period, the prosthetic phase begins. Errors during this phase can lead to failure or complications.
Inaccurate impression taking leading to a lack of passivity
High stresses are exerted on ankylosed implants, which induce peri-implant bone resorption.
Prosthetic sealing with cement rocket in the sulcus
The presence of cement causes chronic irritation to the bone or gum, and peri-implantitis may develop.
Elements screwed with too low a torque
Occlusal overloads
Prematurity concentrates high stresses at one point, they induce bone lysis which can lead to loss of the implant.
Inappropriate clinical crown/implant ratio
The occlusal scheme, the prosthetic design and the number of implants are also among the criteria to be considered to reduce the prosthetic complication rate.
4.5. Failures and complications initiated during implant function
Unscrewing a component
Unscrewing can affect all screwed components of the rehabilitation, abutment, abutment screw or occlusal screw. Screwing the abutment back in eliminates the cause of the localized infectious episode.
Implant fracture:
This is the most dangerous failure because the implant must be removed. It is often associated with bone loss of the crest. Removal is usually performed with a trephine; the procedure is always invasive.
Fracture of the cosmetic material or prosthetic infrastructure
Ceramic fractures are quite rare, however they can affect up to 15% of prostheses. They are classified into minor and major fractures.
Aesthetic failures:
the implants are osseointegrated but the aesthetic result is disappointing. A rigorous pre-implant prosthetic analysis can help avoid this pitfall: study models, diagnostic wax, assessment of bone volume.
Conclusion
The best way to manage failure is to avoid it, and this is achieved by applying preventive measures involving a complete pre-implant assessment, a carefully considered treatment plan, good training of the practitioner and their ability to accurately assess their level of skills, and rigorous maintenance. Failures in implantology
Introduction :
Despite the high success rates and stability of dental implants, failures do occur. While surgical trauma and bone volume and quality are generally considered the most important etiological factors for early implant failure, the etiology of late failures is more controversial.
Early detection and treatment of early progressive bone loss around dental implants by mechanical debridement, antimicrobial therapy and regenerative therapy are the keys to salvage early implant failure.
1. Criteria for evaluating implementation success:
According to the American Academy of Periodontology 2003:
– Absence of persistent signs/symptoms such as pain, infection, neuropathies, paresthesias and violation of vital structures
– Immobility of the implant
– No continuous peri-implant radiolucency
– Negligible progressive bone loss (less than 0.2 mm per year) after physiological remodeling during the first year of operation
– Patient/dentist satisfaction with implant-supported restoration
According to Bartolucci and Mangano:
Implant success depends on:
– Good hygiene
– Implantation and high-performance surgery
– Prosthesis adapted to balanced occlusion
– Favorable local and general conditions. TABLE 1. Criteria for assessing the success of TABLE 1. Criteria for assessing the success of
2. Difference in failure and complication:
Failures = removal of the implant but also aesthetic or functional failures.
Complications = appearance of a new morbid phenomenon during an illness or injury, often temporary and reversible.
3. Risk factors for dental implant failure:
3.1. Practitioner-related factors:
Preoperative: planning error…
Intraoperative: It is estimated that approximately 3.6% of implant failures are related to surgical trauma, also, thermal bone necrosis is a rare phenomenon and one of the causes of early implant failure.
Post-operative: Poor crown design and guidance contribute to failure.
3.2. Implant-related factors:
Dental implant materials and surface characteristics:
Most dental materials currently used clinically are quite biocompatible in human tissues in their specific dental application. They are usually made of titanium, titanium-aluminum vanadium (Ti-6Al-4V), cobalt-chromium-molybdenum, and more rarely other alloys. The most common type of failure is due to poor treatment planning and/or poor surgical execution. The incidence of this type of failure has been estimated at 10%.
3.3. Patient-related factors :
Local factors:
3.3.1. Bone quality and quantity: The most important local factor for the success of implant treatment is bone quality and quantity.
Jaffin and Berman,17 in their 5-year analysis, reported that 35% of implant failures occurred in type IV bone
3.3.2. Irradiated bone : Although radiotherapy is not an absolute contraindication to implant treatment, the success rate is only approximately 70%.
3.3.3. Biomechanical loading of occlusion :
High mechanical load leads to bone resorption. Osteocytes increase the secretion of collagenase-1 [matrix metalloproteinase-1 (MMP-1)] under mechanical load, which can trigger bone resorption. MMP-1 degrades bone collagen types I and III, the main structural collagens of bone.
Smoking as a risk factor for implant failure
The success rate of dental implants is twice as high in non-smokers as in smokers. The maxillary implant is the most affected.
Parafunctional habits and bruxism
Parafunctional habits are also linked to increased peri-implant bone loss.
Systemic factors
Systemic factors affect both bone quality and quantity. These systemic factors include poorly controlled diabetes, osteoporosis, osteomalacia, radiation, certain ongoing medications, and other conditions.
Diabetes mellitus
Diabetes mellitus has also been considered a risk factor and sometimes even a contraindication for dental implants. Recently, dental implants in diabetics have been reported to be successful, at least in the short term.
Osteoporosis
Implants in patients with osteoporosis have shown good short-term results, but long-term results have not been reported.
Medications and radiotherapy
Some medications used clinically cause bone loss, particularly glucocorticosteroids. Other medications containing chemotherapy agents, such as doxorubicin and methamphetamine, such as doxorubicin and methotrexate, inhibit osteoblasts and decrease bone formation. Radiation had no effect on the short-term success rate of implants.
Age
Theoretically, older patients will have systemic health problems, but there is no scientific evidence correlating advanced age with implant failure.
4. Implant failures:
Failures can be classified into different stages:
– preparation of the treatment plan
– surgical phase
– healing phase
– prosthetic phase
– putting the implant into operation.
- Failures and complications initiated during treatment preparation:
These are errors related to an incomplete history of bruxomania, a systemic disease (bone metabolism disease, uncontrolled diabetes) or an unexpected rare disease.
- Failures and complications initiated during the surgical phase
These are objective failures.
Preparation for the procedure and a precise, atraumatic, and tissue-preserving surgical technique are of the utmost importance.
Mandibular canal rupture
The risk of damage to the inferior dental nerve must be constantly kept in mind, which is why a safety distance of 2 mm above the mandibular canal is introduced. If intrusion is detected, the implant positioning must be corrected immediately.
Heating of the bone during drilling:
Too high a temperature rise above 47° degrees for 1 minute causes fibrous encapsulation at the bone-implant interface.
Excessive compression of the bone,
Lack of asepsis during surgery,
Primary stability defect:
Over-drilling of the implant site decreases primary stability.
Incomplete screwing of a cover screw or healing abutment
This event may have no consequences, but it may also cause tissue necrosis or local infection.
Undetected fenestrations or dehiscences:
The bone defect itself is not a problem if it is detected during placement because different techniques are available to fill the bone deficiency (bone grafting, guided bone regeneration). On the other hand, if it has not been identified, it can lead to fibrous encapsulation.
Implant malposition:
The implant is placed in a position dictated by the presence of available bone and not by prosthetic needs. It can be osseointegrated but does not meet aesthetic requirements, the position is too mesial, too distal, too vestibular or too palatal in relation to the axis of the rehabilitated tooth.
4.3. Failures and complications initiated during the healing phase
These objective failures are also one of the causes of primary failures.
Uncontrolled forces exerted on the implant
This can occur when compulsive repeated pressure is applied with the tongue or when hard food is introduced too quickly after surgery.
Infection
The first stage, mucositis, is reversible; it does not affect the bone surrounding the implant. However, peri-implantitis leads to bone loss.
4.4. Failures and complications initiated during the prosthetic phase
At the end of the healing period, the prosthetic phase begins. Errors during this phase can lead to failure or complications.
Inaccurate impression taking leading to a lack of passivity
High stresses are exerted on ankylosed implants, which induce peri-implant bone resorption.
Prosthetic sealing with cement rocket in the sulcus
The presence of cement causes chronic irritation to the bone or gum, and peri-implantitis may develop.
Elements screwed with too low a torque
Occlusal overloads
Prematurity concentrates high stresses at one point, they induce bone lysis which can lead to loss of the implant.
Inappropriate clinical crown/implant ratio
The occlusal scheme, the prosthetic design and the number of implants are also among the criteria to be considered to reduce the prosthetic complication rate.
4.5. Failures and complications initiated during implant function
Unscrewing a component
Unscrewing can affect all screwed components of the rehabilitation, abutment, abutment screw or occlusal screw. Screwing the abutment back in eliminates the cause of the localized infectious episode.
Implant fracture:
This is the most dangerous failure because the implant must be removed. It is often associated with bone loss of the crest. Removal is usually performed with a trephine; the procedure is always invasive.
Fracture of the cosmetic material or prosthetic infrastructure
Ceramic fractures are quite rare, however they can affect up to 15% of prostheses. They are classified into minor and major fractures.
Aesthetic failures:
the implants are osseointegrated but the aesthetic result is disappointing. A rigorous pre-implant prosthetic analysis can help avoid this pitfall: study models, diagnostic wax, assessment of bone volume.
Conclusion
The best way to manage failure is to avoid it, and this is achieved by applying preventive measures involving a complete pre-implant assessment, a carefully considered treatment plan, good training of the practitioner and their ability to most accurately assess their level of skills, and rigorous maintenance .
Failures in implantology
Untreated cavities can cause painful abscesses.
Untreated cavities can cause painful abscesses.
Dental veneers camouflage imperfections such as stains or spaces.
Misaligned teeth can cause digestive problems.
Dental implants restore chewing function and smile aesthetics.
Fluoride mouthwashes strengthen enamel and prevent cavities.
Decayed baby teeth can affect the health of permanent teeth.
A soft-bristled toothbrush protects enamel and sensitive gums.