Contents

Introduction. 3

Peri Implant Tissues in Clinical Health. 3

Differences in Anatomy between Teeth and Implants. 4

Risk Factors for Peri-Implant Disease. 4

Planning Stage of Dental Implants. 6

Medical and Dental Histories. 7

Examination of Clinical Implant. 7

Plaque Index. 7

Clinical Probing Depths. 8

Bleeding on Probing. 8

Keratinized Tissue (KM). 8

Mobility. 9

Occlusion. 9

Bone Level 10

Suggested Maintenance Protocol 10

Disease Control 10

Health Maintenance. 11

Scaling and Root Planing. 11

Follow-up and evaluation of health and disease around implants. 12

Home Care. 12

Follow-up Protocol 13

Antimicrobial Treatment. 13

Role In Implant Maintenance. 14

Patients role. 14

Hygienists Role. 14

Dentists Clinical Role. 14

Conclusion. 15

References. 16

Introduction

As implant treatment becomes part of mainstream dental therapy, dentists should provide customised protocols for the systematic and continuous supportive care for peri-implant tissue. The initial assessment should begin with updating the medical and dental histories. The clinical implant should be examined to evaluate the following: condition of the soft tissue, plaque index, clinical probing depth, bleeding on probing, suppuration, stability of soft-tissue margins, keratinised tissues, mobility and occlusion. If clinical signs suggest peri- implantitis, radiography of the site is suggested to confirm the diagnosis. Suitable treatment should be followed according to the diagnosis reached during the examination, including oral hygiene instruction, removal of supra and sub gingival plaque and calculus, occlusal adjustment, relining of a removable prosthesis or surgery (Todescan, et al., 2012).

Patients who have undergone successful implant therapy should receive customised, methodical and continuous supportive care of peri implant tissues. Patients at higher risk for peri implantitis, those with partial edentia or pre-existing chronic periodontitis, should be identified and monitored closely (Lindhe & Meyle, 2008). Studies have also demonstrated that sites of pre-existing infection may act as reservoirs for periopathogens, which can colonize the implant, especially in patients with diabetes mellitus who have poor diabetic control, those with poor plaque control and those who smoke cigarettes (Quirynen, et al., 2007).

Peri Implant Tissues in Clinical Health

Peri implant tissues are those tissues that occur around osseointegrated dental implants. They are divided into soft and hard tissue compartments. The soft tissue components are known as the “peri-implant mucosa” and is formed during the wound healing process. the hard tissue component forms a contact relationship to the implant surface to secure implant stability. Due to their histologic and anatomic features, peri implant tissues carry out two basic functions: the mucosa protects the underlining bone, while the bone supports the implant. The destruction of peri implant tissues allows the recognition of disease (Araujo & Lindhe, 2017).

Differences in Anatomy between Teeth and Implants

A natural tooth is surrounded by keratinized mucosal tissue surrounding the crown of the tooth (Lindhe, et al., 2008). When bacteria accumulate around this keratinized mucosal tissue, this tissue becomes inflamed and gingivitis develops. When an implant is placed, these tissues are now considered peri-implant tissues. When these tissues become inflamed and bone loss occurs in the natural dentition, it is known as periodontal disease. When bone loss is experienced around a dental implant, the disease is known as peri-implantitis (Lindhe & Meyle, 2008). Natural teeth that are not restored have a pulp chamber in the center that provides sensory feeling to the tooth. Due to the nerve fibers within the tooth, if the tooth gets diseases the patient will feel pain. This pain can prompt patients to visit a dental professional.

Implants do not have any nerves and, as a result, disease can go unnoticed by patients. Natural teeth also have a periodontal ligament that supports the tooth and keeps it stable. Implants do not have a periodontal ligament attachment and, hence rely on support from the bone. While plasma cells and lymphocytes dominate in both types of lesions, neutrophil granulocytes and macrophages occur in larger proportions in peri-implantitis than in periodontitis. A “self-containing” process exists in the tissues around teeth, which results in a protective connective tissue capsule that separates the lesion from the alveolar bone. Such a self-containing process does not occur in peri-implant tissues, and the lesion extends to the bony crest (Lang & Berglundh, 2011). Together, these anatomical differences make the implant much more susceptible to bacterial invasion and inflammation, necessitating special care prior to and following dental implant placement. This review addresses some of the important aspects of implant management and maintenance.

Risk Factors for Peri-Implant Disease

Peri-implantitis is a growing concern surrounding the placement of dental implants. Peri-implantitis is characterized by changes in the level of the crestal bone in conjunction with bleeding on probing with or without related deepening of peri-implant pockets.

Pus is a common finding in peri-implantitis sites.

A study published in 2016 analyzed 588 implant patients for the prevalence of peri-implantitis. The study defined peri-implantitis as bone loss over 0.5 mm and bleeding on probing. An astounding 45% of patients presented with the disease. (Derks, et al., 2015).

A concept review published in 2015 found the prevalence of peri-implantitis to have a range of 4.7% to 43% at the implant level (Marcantonio, et al., 2015). Peri-implantitis is a concern that needs to be addressed and considered both prior to and following implant placement. The most important and crucial cause for peri-implantitis is bacterial plaque accumulation around the implantation site. Several risk factors are associated with the presence of peri-implant disease. The most significant risk factor is poor oral hygiene. There is evidence that poor oral hygiene is associated with peri-implant diseases with an odds ratio of 14.3 (Lindhe & Meyle, 2008).

Smoking is a strongly associated risk factor regarding the prevalence of peri-implant disease. (Levin, et al., 2008). The consumption of tobacco smoke alters the microbiome in the peri-implant tissues and allows the colonization of harmful bacteria (Tsigarida, et al., 2015). Smoking also doubles the marginal bone loss observed versus that seen in nonsmokers. Therefore, we should carefully contemplate the placement of implants in the smoking patient as smoking is strongly associated with peri-implant disease. Patients with a history of periodontal disease or current periodontal disease are also at high risk for developing peri-implantitis (Marcantonio, et al., 2015). According to a study by Dalago et al. (2016), patients with a history of periodontal disease had a 2.2-times greater risk for peri-implantitis than those who did not. (Dalago, et al., 2016). Periodontal disease has also been associated with peri-implantitis in earlier studies. The periodontal pathogens associated with the disease are thought to colonize the tissues surrounding the implant leading to peri-implantitis. Therefore, there should be special consideration prior to placing implants in a patient presenting with a history of periodontal disease. Careful treatment to resolve periodontal disease activity should precede implant placement, and a strict and frequent maintenance protocol should be adopted in those patients (Clark & Levin, 2016).

Cemented versus screw-retained implants may also present as risk factors for peri-implantitis (Clark & Levin, 2016). Implants that are cement-retained are shown to have an increased prevalence of peri-implantitis when compared to screw-retained implants This is most likely attributed to the presence of excess cement in the sulcus that enhances the bacteria’s ability to colonize. However, a study published by Dalago et al. (2015) found that there was no difference in the prevalence of peri-implantitis in cement versus screw-retained implants if the cement was properly removed (Dalago, et al., 2016). If placing a cement-retained implant, it is crucial to utilize proper techniques to ensure appropriate removal of the cement or other plaque-retentive factors.

Diabetes is a systemic factor that has been associated with increased risk for peri-implantitis (Clark & Levin, 2016). It is known that diabetic patients are more prone to periodontal disease and other infections; however, their susceptibility to peri-implantitis remains controversial. Diabetic patients with poor metabolic control are considered high risk for peri implant disease. A patient who is supposed to receive implant placement should present with well-controlled diabetes to ensure the best prognosis of the implant. Risk factors, such as diabetes, that are associated with peri-implant disease are usually in case study research. It has been pointed out that these studies have been useful for hypothesizing, but there remains a need for observational studies to further research the association between diabetes and peri-implantitis (Rocchietta & Nisand, 2012). Peri-implantitis can lead to implant failure. To maximize implant longevity and success, we need to assess patients for risk factors that may make them more vulnerable. From there, we can assess if implant placement should take place, and if so, provide the patient with management techniques to combat and control their risk factors. Those risk factors should be discussed and should be part of the consent process for implant placement.

Planning Stage of Dental Implants

It is vital to enable good oral hygiene and long-term maintenance behavior to ensure success of dental implants. It is important to include oral hygiene in the planning stage. Instead of treating peri-implantitis when it presents, we should be ensuring its prevention before the implants are even placed. Since periodontal disease is considered a risk factor for peri-implantitis, a patient’s periodontal diagnosis should be noted (Clark & Levin, 2016). The patient’s periodontal status should be stable prior to placing implants. This may involve introducing and enforcing an improved dental hygiene protocol. Nonetheless, professional preventative care is insufficient in preventing peri-implantitis. Mechanical plaque removal is the most effective preventative measure for successful implants (Tonetti, et al., 2015). Therefore, patient education about oral home care and long-term maintenance behavior is crucial, and ensuring the patient is complying with home care routines is imperative to maintain implant health. This should be achieved before implant placement occurs; patients should prove they are responsible and capable of maintaining oral health and plaque control to have the opportunity of receiving dental implants.

Medical and Dental Histories

The assessment begins with updating the medical and dental histories, to ensure that all related conditions and therapies are known and identified in high risk categories.

Examination of Clinical Implant

Soft Tissue Assessment: The soft tissue assessment includes checking for signs of inflammation around the implant, such as redness, swelling, alterations of contour and consistency, atypical gingival form and the presence of fistulas.

Plaque Index

An objective form of plaque monitoring must be performed and documented at every maintenance visit, to allow for linear assessment of oral hygiene. There are many different types of plaque indices, however we must be consistent with the index which is more important than the type of index. Implant specific plaque indices have been described by Lindquist et al. (1988) and Mombelli et al. (1995) (Mombelli, et al., 1995) (Lindquist, et al., 1988).

Rough surfaced implants, such as those sprayed with titanium plasma for humans and porous anodized implant surfaces for dogs have been shown to accumulate greater amounts of plaque than smooth surfaced implants. This may increase the risk of peri implantitis. Bacterial adhesion has also been shown to be influenced by rough surfaces, with a higher subgingival bacterial load on rough surfaces. Some studies have shown no correlation between inflammatory response and the roughness of abutment surfaces, no correlation between inflammatory response and biofilm, and no evidence that characteristics of the implant surface affects the initiation of peri implantitis (Renvert, et al., 2011).

(Todescan, et al., 2012)

Clinical Probing Depths

Probing is an important and reliable diagnostic parameter in the longitudinal monitoring of peri implant soft tissues. The safety of probing around implants has been well established and does not seem to affect the integrity of the implant. It has been reported by Etter et al (2002) that healing of the epithelial attachment is complete 5 days after clinical probing (Etter, et al., 2002).

During installation of the prosthesis, it is important to establish baseline values for the probing depths. Probing depths for tissue level implants generally range between 2 -4mm whilst implants placed at bone level may exhibit greater clinical probing depths. Increases in both the clinical probing depth over time are usually associated with loss of attachment and bone loss and should be viewed as signs of peri implant disease (Lindhe, et al., 2008).

Bleeding on Probing

Like natural teeth, the absence of bleeding on probing had a high negative predictive value and can then be interpreted to represent stability of the peri-implant tissue (Luterbacher, et al., 2000).

Keratinized Tissue (KM)

Keratinised mucosa is a term used to describe the masticatory mucosa that is present at many, but not all implant sites. KM extends from the margin of the peri-implant mucosa to the movable lining mucosa.

The need for minimum KM to maintain peri- implant health is apparently a controversial issue. Studies have failed to associate the lack of a minimum amount of KM with mucosal inflammation, whilst other studies suggest that plaque build-up and marginal inflammation were more frequent at implant sites with <2mm KM. In the absence of KM around implants, the indications for soft tissue grafting are unclear, and intervention will depend on case-by-case evaluation (Araujo & Lindhe, 2017).

Mobility

Motility of dental implants should be assessed routinely, either manually or by automated means. These include the Periotest dental measuring instrument or the Ostell instrument. (Sennerby & Meredith, 2008). If a single implant is mobile in a multi-unit fixed prosthesis, the mobility maybe masked. Therefore, it is suggested fixed, multiunit, retrievable implant- retained prosthesis be removed periodically to assess mobility, gingival health and hygiene status. The cause of mobility must always be ascertained, specifically whether it is due to failure of the prosthetic or osseointegration failure (Humphrey, 2006). If the implant becomes mobile, it is deemed to have failed and should be removed.

Occlusion

Occlusal schemes should provide for adequate posterior support at an appropriate vertical dimension. Eccentric guidances should be used to ensure optimal distribution of harmful effects of excursive occlusal parafunction. If technical complications occur, they should be treated accordingly. Parafunctional habits should be documented and treated, since application of excessive concentrated forces can cause rapid and severe peri-implant bone loss (Humphrey, 2006).

A traumatic occlusion is another potential cause of bone loss around an implant. Hence an occlusal examination should be performed during the implant maintenance consultation. Studies performed in monkeys suggest a possibility of bone resorption around dental implants with 180micrometes of excess suprastructure height, even in the absence of inflammation in the peri implant tissue. For fixed restorations, light centric contacts and avoidance of non-centric interferences are recommended. During the occlusion assessment, shim stock should be held only with tightly clenched teeth, to ensure avoidance of excessive occlusal loading of implants (Misch, 2005).

Bone Level

If there are clinical signs of peri-implantitis, radiography of the site should be performed to confirm the diagnosis. However, radiography during maintenance care should be performed based on need. The radiographic technique must be standardized so that the interface between the bone and implant is well delineated. There should be complete seating of the abutment or restoration, absence of restorative overhangs and removal of all restorative cements should also be verified. As these areas predispose the patient to long term

complications (Schumaker, et al., 2009). For accurate radiograph readings, a baseline bone level must be established after implant placement and again after prosthesis insertion. Dental implants with machined surfaces and external hex connections will be subject to remodelling around the coronal part of the implant (1.5mm in the first year and then 0.1mm per year thereafter). The external hex implant has been changed to include an internal hex connection and micro threading at the implant neck. These changes are to create a tight, stable biological seal and platform switching. Dental implants that incorporate these macro and micro structural changes seem to have reduced initial crestal bone remodelling during healing and under functional load (Abrahamsson & Berglundh, 2009). Evaluation of marginal bone levels should consider the specific implant system, to avoid misdiagnosis of peri- implantitis in case of normal remodelling.

Suggested Maintenance Protocol

Disease Control

Before placing dental implants, any existing disease such as periodontitis should be treated to prevent failure of the implants. However, if peri-implantitis occurs, after implants are placed the disease needs to be controlled as quickly as possible to prevent bone loss around the implants. Up to 6-months’ recall is recommended for implant patients who have no complications and are in a maintenance phase (Bidra, et al., 2015). If peri-implantitis is present, the recall interval should be more regular to control the disease. Oral homecare may also need to be reviewed if patient plaque removal is insufficient. The professional care recall visits should include professional cleaning of the teeth and implants, but also repeated oral hygiene instructions and reinforcement as well as evaluation of the complete oral health, to make sure we detect any pathology, including peri-implantitis, as early as possible

(Clark & Levin, 2016).

Health Maintenance

Lifetime professional maintenance from dental professionals for patients with implant restorations is necessary. Patients diagnosed with peri-implant disease had more improvement in their peri-implant health if they received regular professional care versus patients who had no professional maintenance. The recommended recall for a dental examination assessing oral health is 3 to 6 months for patients with implants (Bidra, et al., 2015) . However, factors that increase a patient’s risk for disease such as home care habits, smoking, diabetes, history of periodontal disease, and complications should intensify recall frequency (Bidra, et al., 2015). During these recall visits, it is compulsory that oral hygiene education is assessed and reviewed with the patient to maintain compliance. The patient’s plaque removal efficacy should be determined, and areas for improvement should be recognized during these visits. Frequent recalls remind the patient about their responsibility in maintaining their implants and ensuring implant success. Full-mouth probing should be performed on a patient-centered basis, with a full mouth probe occurring at least once per year in a periodontally healthy patient. Areas of concern should be probed at each recall appointment, and diseased pockets should be treated appropriately.

Scaling procedures will also occur during the recall appointments to reduce the development of peri-implantitis. Nonetheless, plaque and calculus should be removed effectively from implant surfaces as well as teeth, and therefore it seems reasonable to use regular metal scalers and curettes on implant restorations. It should be remembered that if the tissues are healthy around the implant, the curettes will not reach the implant surface that is covered with bone. When peri-implantitis is present, it is even more essential to remove the debris effectively. The use of more gentle curettes in these cases will probably not suffice and, as a result, regular metal scalers should be effective (Clark & Levin, 2016).

Scaling and Root Planing

Scaling and root planning procedures entail the use of plastic curettes and fine polishing pastes. Professional maintenance should include removing both soft and hard tissue deposits with plastic scalers. The use of a plastic curette on the implant is not recommended due to its ineffectiveness in removing biofilm. Another disadvantage of using scalers that are softer than the titanium implant is the plastic remnants that are left behind on the tooth surface after the scaling is completed. Minimal research is available regarding the optimal scaler for debriding implants (Clark & Levin, 2016). There is a need for further research regarding the most effective tool for professional mechanical debridement for implants. Highly flexible plastic instruments can be difficult to use when removing calculus from implant surfaces. However, plastic instruments reinforced with graphite are more rigid and can be sharpened. Instruments that may scratch the implant surface which facilitates biofilm growth such as stainless steel, titanium, ultrasonic tips and gold tipped instruments should be avoided. Newly developed plastic- covered and novel metallic copper alloy ultrasonic scaler tips have minimal effects on titanium surface of implants. Using a fine polishing paste does not appear to scratch the implant surface but there are conflicting results regarding the use of air- polishing abrasives on implant surfaces.

Follow-up and evaluation of health and disease around implants

Important factors that should be considered during the follow-up of implant placement include oral health status and home care performance. Bleeding upon probing and marginal bone loss are defining factors of peri-implantitis and should be assessed during the follow-up and recall visits. If no inflammation exists and the patient is participating in satisfactory home care, the implant is being maintained and should proceed to be successful.

Home Care

Plaque control is critically important for the maintenance of dental implants as it is for natural teeth. Hence it is imperative that patients understand their role and responsibility in maintaining their implants. A home care assessment should have been performed before placement of the implant fixture, whether an initial assessment was performed or not, review and reinforcement at maintenance appointments are essential. A through oral hygiene regimen must be customized according to the condition of the tissue and the extent of plaque and calculus around dental implants should be implemented. Home care devices and aids that have been safe for use around implant surfaces include interdental brushes with nylon coated wire core, soft tooth brushes, tuft brushes, gauze, and many types of floss, dental tape, stannous fluoride gel and chlorhexidine. Home care instructions should be customized according to implant design and accessibility.

Follow-up Protocol

For optimum effect home care at the gingival/implant junction, hygiene is accomplished with the use of an interdental or ultrasonic brush.

The ultrasonic brush is effective in posterior segments and from the lingual aspects where there is difficult access as the superstructure conceals the implant post from normal oral hygiene procedures. The dentist should instruct the patient immediately after placement of the prosthesis, and instruction should be part of the treatment protocol.

To facilitate home care procedures, the superstructure must be self-cleansing and completely fixture borne with adequate embrasures for hygiene instrument access. The superstructure should not be unhygienic as it would lend itself to plaque accumulation, gingival inflammation and ineffective maintenance.

A maintenance protocol relating to the care of the dental implants might entail a recall visit every 3 months. At this visit the dentist documents the hygiene effectiveness and assesses the superstructure by inserting an instrument under the prosthesis and gently prying it up, noting any movements in the super structure. Movements would indicate implant failure, prosthesis fracture, screw failure, possible cement failure to bond the superstructure and retainer.

To complement the 3 month, recall visits, the dentist should obtain peri apical radiographs every 6 months to document changes in osseous topography (Misch, 2005).

Antimicrobial Treatment

To ensure optimum health around the dental implant requires the following:

– Inhibition of plaque

– Elimination of early microbial population on tooth/implant surfaces

– Elimination of all existing plaque

– Alteration of the existing plaque from pathogenic to non-pathogenic microorganisms

Antimicrobials brought about the minimum alteration of the implant surfaces studied, so an effective means of soft tissue maintenance around dental implants includes the use of a mouthwash containing commercially available compounds such as phenolic agents, plant alkaloids or chlorhexidine gluconate (Misch, 2005).

Many implantologists use chlorhexidine gluconate because of its demonstrated binding action to the tissues in the oral cavity. Chlorhexidine gluconate has demonstrated close to 100% bacterial kill of the oral bacteria in a 0.12% concentration even after 5 hours after a 30 second rinse (Misch, 2005).

Role In Implant Maintenance SUMMARY

Patients role

– Maintain plaque control of 85% or better

– Use interdental brushes, hand and motorized

– Dip brushes in chlorhexidine at night before sleeping

– Use flosses, yarns and tapes dipped in chlorhexidine before sleeping

– Use a cotton swab dipped in chlorhexidine for implants with a tooth colored materials and composites (Misch, 2005).

Hygienists Role

– Check plaque control effectiveness (85%)

– Check for inflammatory changes

– If pathologic changes are present, probe gently with a plastic probe

– Scale supragingivally only or slightly subgingivally

– Check for problems such as loose suprastructure, broken screws, and sore spots

– No need to probe if no pathologic condition is present (Misch, 2005).

Dentists Clinical Role

– Check patient every 3 to 4 months (implant patient is a periodontic patient)

– Check for 85% plaque control effectiveness

– Expose radiographs every 12 to 18 months if no pathologic conditions is present, and as needed if pathologic condition is present

– If implant needs repair, degranulate, detoxify, and graft with guided bone regeneration if necessary

– Wait 10-12 weeks before placing implant into full function. Check to see whether the implant needs to be repaired (Misch, 2005).

Conclusion

Dental implants are proven to be a predictable long-term treatment for patients, however it must be noted that not all implants that survive are necessarily successful. Successful implants remain fully functional and are healthy with the oral cavity. Peri-implantitis is a disease associated with implant failure. Risk factors must always be assessed, and existing periodontal disease must be stabilised before dental implant placement. Which will assist in preventing implant disease and failure. Following the placement of dental implants, a regular maintenance regime should be implemented to monitor the implant and surrounding teeth for disease or failure. Patients must be continually encouraged to adhere to consistent home care to prevent any disease around the implants. Regular professional visits will allow for early diagnosis and elimination of any inflammatory disease around the implants and will also improve the long-term prognosis (Clark & Levin, 2016).

References

Abrahamsson, I. & Berglundh, T., 2009. Effects of different implant surfaces and designs on marginal bone level alterations: a review. Clinical Oral Implants Research, 20(4), pp. 207-215.

Araujo, M. & Lindhe, J., 2017. Peri- implant health. Journal of Periodontology, 89(1), pp. 249-256.

Bidra, A., Daubert, D., Garcia, LT.; Kosinski, TF.; Nenn, CA.; Olsen, JA.; Platt, JA.; Wingrove, SS.; Chandler, ND.; Curtis, DA., 2015. Clinical practice guidelines for recall and maintenance of patients with tooth-borne and implant borne dental restorations.. Journal of Prosthodontics, 25(1), pp. 32-40.

Clark, C. & Levin, L., 2016. Dental implant management and maintenance:How to improve long-term implant success?. Quintessence International, 7(5), pp. 417-423.

Dalago, H.; Schuldt, FG.; Rodrigues, MA.; Renvert, S.; Bianchini, MA., 2016. Risk indicators for peri-implantitis. A cross-sectional study with 916 implants.. Clinical Oral Implants Research., 28(2), pp. 144-150.

Derks, J.; Schaller, D.; Hakansson, J.; Wennstrom, JL.; Tomasi, C.; Berglundt, T., 2015. Effectiveness of implant therapy analyzed in a swedish population: prevalence of peri-implantitis. Journal of Dental Research, Volume 95, pp. 43-49.

Etter, T.; Hakansson, J.; Lang, NP.; Trejo, PM.; Caffesse, RG., 2002. Healing after standardized clinical probing of the periimplant soft tissue seal: a histomorphometric study in dogs. Clinical Oral Implants Research, 13(6), pp. 571-580.

Humphrey, S., 2006. Implant Maintenance. Dental Clinics of North America, 50(3), pp. 463-478.

Lang, J. & Berglundh, T., 2011. Periimplant disease: where are we now?Consensus of the Seventh European Workshop on Periodontology. Journal of Clinical Periodontology, 38(11), pp. 178-181.

Levin, L., Hertzberg, R., Har Nes, S. & Schwartz Arad, D., 2008. Long-term marginal bone loss around single dental implants affected by current and past smoking habits.. Implant Dentistry, Volume 17, pp. 422-429.

Lindhe, J., Lang, N. & Karring, T., 2008. Clinical periodontology and implant dentistry.. s.l.:Oxford: Blakwell Munksgaard.

Lindhe, J. & Meyle, J., 2008. Peri-implant diseases: Consensus Report of the Sixth European. Journal of Clinical Periodontology, 35(8), pp. 282-285.

Lindquist, L., Rockler, B. & Carlsson, G., 1988. Bone resorption around fixtures in edentulous patients treated with mandibular fixed tissue- integrated prosthesis. Journal of Prosthetic Dentistry, Volume 1, pp. 59-63.

Luterbacher, Mayfield, L., Bragger, U. & Land, N., 2000. Diagnostic Characteristics of clinical and microbiological tests for monitoring periodontal and peri implant mucosa; tissue conditions during supportive periodontal therapy (SPT).. Clinical Oral Implants Research., 11(6), pp. 521-529.

Marcantonio, C., Nicoli, L., E., M. J. & D., Z.-B., 2015. Prevalence and possible risk factors of peri-implantitis: a concept review.. Journal of Contemporary Dental Practise., Volume 16, pp. 750-757.

Misch, C., 2005. Dental Implant Prosthetics. China: Mosby.

Mombelli, A.; Marxer, M.; Gaberthuel, T.; Grunder, U.; Land, NP., 1995. The microbiota of osseointegrated implant in patients with a history of periodontal disease.. Journal of linical Periodontology, 22(2), pp. 124-130.

Quirynen, M.; Abarca, M.; Van Assche N.; Nevins, M.,2007. Impact of supportive periodontal theraphy and implant surface roughness on implant outcome in patients with periodontitis.. Journal of Clinical Periodontitis, 34(9), pp. 805-15.

Renvert, S., Polyzois, I. & Claffey, N., 2011. How do implant surface characteristics influence peri-implant disease. Journal of Clinical Periodontology, 38(11), pp. 214-222.

Rocchietta, I. & Nisand, D., 2012. A review assessing the quality of reporting of risk factor research in implant dentistry using smoking, diabetes and periodontitis and implant loss as an outcome: critical aspects in design and outcome assessment.. Journal of Clinical Periodontology., Volume 39, pp. 114-121.

Schumaker, N., Metcalf, B., Toscano, N. & Holtzclaw, D., 2009. Periodontal and periimplant maintenance: a critical factor in long term treatment success.. Compendium Cont Educ Dent., Volume 7, pp. 388-394.

Sennerby, L. & Meredith, N., 2008. Implant stability measurements using resonance frequency analysi: biological and biomechanical aspects and clinical aspects.. Periodontolgy 2000, Volume 47, pp. 51-66.

Todescan, S., Lavigne, S.; Cholakis, AK., 2012. Guidance for the Maintenance Care of Dental Implants: Clinical Review. Journal of the Canadian Dental Association, 78(107).

Tonetti, M., Chapple, I., Jepsen, S. & Sanz, M., 2015. Primary and secondary prevention of periodontal and peri-implant disease.. Journal of Clinical Periodontology., Volume 42, pp. 1-4.

Tsigarida, A., Dabdoub, S., Nagaraja, H. & Kumar, P., 2015. The influence of smoking on the peri- implant microbiome.. Journal of Dental Research, Volume 94, pp. 1202-1217.