Histological evaluation of osseointegration between conventional and novel bone-level tapered implants in healed bone-A preclinical study.

AIMS: To histologically compare osseointegration and crestal bone healing between newly introduced tapered, self-cutting bone-level test implants and tapered bone-level control implants in sites with fully healed sites. METHODS: Sixty-six implants (33 test, 33 control) were placed 1 mm subcrestally in a minipig model and underwent qualitative histologic and quantitative histometric analyses after 3, 6 and 12 weeks of submerged healing. The primary and secondary outcomes were the bone-to-implant contact (BIC) and first bone-to-implant contact (fBIC). Outcomes between the test and control implants were statistically compared. RESULTS: The BIC values of the test implants were comparable and non-inferior over the time points studied, except for the 12 weeks time point which showed statistically significantly higher BIC values of the test (88.07 ± 5.35%) compared to the control implants (80.88 ± 7.51%) (p = .010). Similarly comparable and non-inferior were the fBIC values, except for the 6-week outcome, which showed statistically higher values for the test (-546.5 ± 450.80 µm) compared to the control implants (-75.7 ± 100.59 µm). fBIC results for the test implants were qualitatively more stable and consistent between test time points. CONCLUSION: Novel self-cutting bone-level test implants demonstrated superior osseointegration and similar bone levels compared to conventional bone-level implants after a healing period of 12 weeks in healed ridges.

Early and late implant loss in a university-based periodontal setting: A retrospective analysis on 1821 patients and 2639 implants over a period of 18 years.

The aim of this study was to retrospectively analyze the implant failure rate, not due to peri-implantitis, in periodontally compromised patients rehabilitated with at least one dental implant placed in a specialist university setting over the last 18 years. Records of patients receiving dental implants at the Department of Periodontology, University of Bern, Switzerland, between 2005 and 2022 were analyzed. Data on 1821 patients with 2639 implants were retrieved. Fifty-nine patients experienced implant loss (rate at patient level: 3.2%) out of which 2.1% were early and 1.1% late implant losses, respectively. The majority of the 59 patients were males (68%) and 27.1% were smokers. Eight mm implants were lost with the highest rate (42.4%) followed by 10 mm implants (31.8%). The rate of lost maxillary implants was more than twice as high compared with that of mandibular implants (69.7 vs. 30.3%). Within the study limitations, the implant failure rate in this cohort of patients enrolled in regular supportive periodontal and peri-implant care, was low.

Clinical evaluation of a novel protocol for supportive periodontal care: A randomized controlled clinical trial.

BACKGROUND: The aim of this study was to compare the clinical efficacy and the patient perception of subgingival debridement with either guided biofilm management (GBM) or conventional scaling and root planing (SRP) during supportive periodontal care (SPC). METHODS: Forty-one patients in SPC were randomly assigned to either treatment with GBM or SRP every 6 months. The primary outcome was the percentage of bleeding on probing (BoP) at 1 year. Moreover, pocket probing depths (PPD), recession, and furcation involvements were also measured. Full-mouth and specific site analyzes were performed at baseline, 6 and 12 months of SPC. Patient comfort was evaluated using a visual analogue scale (VAS) at 12 months. RESULTS: At 1 year, mean BoP percentage decreased from 12.2% to 9.0% (p = 0.191) and from 14.7% to 7.9% (p = 0.004) for the GBM and SRP groups, respectively. Furcation involved multirooted teeth but no through-and-through lesions were significantly fewer in the GBM than in the SRP group after 12 months (p = 0.015). The remaining parameters showed slight improvement in both groups without any statistically significant differences between the two groups after 1 year. Pain evaluation as patient reported outcome measures (pain evaluation) was in favor (p = 0.347) of the SRP group, while overall satisfaction was similar for both groups. Treatment time was not statistically significantly different between the two groups (p = 0.188). CONCLUSION: In well-maintained SPC patients, SRP protocols resulted in significant clinical improvements in terms of BoP; however, for the other clinical improvements, similar efficacy for both GBM and SRP was observed.

Preclinical evaluation of a new synthetic carbonate apatite bone substitute on periodontal regeneration in intrabony defects.

OBJECTIVE: To evaluate the potential of a novel synthetic carbonate apatite bone substitute (CO3 Ap-BS) on periodontal regeneration. BACKGROUND: The use of various synthetic bone substitutes as a monotherapy for periodontal regeneration mainly results in a reparative healing pattern. Since xenografts or allografts are not always accepted by patients for various reasons, a synthetic alternative would be desirable. METHODS: Acute-type 3-wall intrabony defects were surgically created in 4 female beagle dogs. Defects were randomly allocated and filled with CO3 Ap-BS (test) and deproteinized bovine bone mineral (DBBM) or left empty (control). After 8 weeks, the retrieved specimens were scanned by micro-CT, and the percentages of new bone, bone substitute, and soft tissues were evaluated. Thereafter, the tissues were histologically and histometrically analyzed. RESULTS: Healing was uneventful in all animals, and defects were present without any signs of adverse events. Formation of periodontal ligament and cementum occurred to varying extent in all groups without statistically significant differences between the groups. Residues of both bone substitutes were still present and showed integration into new bone. Histometry and micro-CT revealed that the total mineralized area or volume was higher with the use of CO3 Ap-BS compared to control (66.06 ± 9.34%, 36.11 ± 6.40%; p = .014, or 69.74 ± 2.95%, 42.68 ± 8.68%; p = .014). The percentage of bone substitute surface covered by new bone was higher for CO3 Ap-BS (47.22 ± 3.96%) than for DBBM (16.69 ± 5.66, p = .114). CONCLUSIONS: CO3 Ap-BS and DBBM demonstrated similar effects on periodontal regeneration. However, away from the root surface, more new bone, total mineralized area/volume, and higher osteoconductivity were observed for the CO3 Ap-BS group compared to the DBBM group. These findings point to the potential of CO3 Ap-BS for periodontal and bone regeneration.

Clinical and histologic evaluation of heterotopic mucosa transpositioning at teeth and dental implants.

AIM: To investigate the healing after heterotopic mucosa transpositioning at dental implants and teeth. MATERIALS AND METHODS: One hemimandible per dog (n = 4) was allocated to receive 3 implants (test), whereby 3 premolars on the contralateral side served as controls. After osseointegration, a Z-plasty was performed on the buccal aspect of the test and control sites to heterotopically move the zone of keratinized tissue (KT) into a region with non-keratinized tissue (nKT) and vice versa. Clinical measurements were performed before (T0) and at 12 weeks following heterotopic transposition (T1). Thereafter, specimens were processed for histological analysis. RESULTS: Clinical measurements revealed that at T1, a band of KT was reestablished at teeth (mean: 2.944 ± 1.866 mm), whereas at implants, the transpositioned nKT resulted in a mucosa without any signs of keratinization (mean: 0 mm; p < .0001). At implant sites, the probing attachment level loss was more pronounced compared to tooth sites (-1.667 ± 1.195 mm and -1.028 ± 0.878 mm, respectively; p = .0076). Histologically, the transpositioned nKT, was accompanied by the formation of KT at the tooth but not at implant sites. The supracrestal soft tissues were statistically significantly higher at tooth compared to implant sites (2.978 ± 0.483 mm and 2.497 ± 0.455 mm, p = .0083). The transpositioned KT remained mostly unaltered in its morphological characteristics. CONCLUSIONS: The findings of this study indicate that: (a) transpositioned KT may retain its morphological characteristics; and (b) transpositioned nKM was accompanied by the formation of KT at the tooth but not at implant sites.

Longitudinal assessment of peri-implant diseases in patients with and without history of periodontitis: A 20-year follow-up study.

PURPOSE: To longitudinally assess the prevalence of peri-implant health, peri-implant mucositis and peri-implantitis in a cohort of patients with and without history of periodontitis over a 20-year period. MATERIALS AND METHODS: Eighty-four patients who attended a specialist private periodontal practice were evaluated prospectively 10 and 20 years after prosthesis delivery. Following successful completion of periodontal/implant therapy, patients (172 implants) were enrolled on an individualised supportive periodontal care programme. Clinical and radiographic parameters were collected to assess the prevalence of peri-implant health and diseases. Prevalence of peri-implantitis and peri-implant mucositis was calculated based on the case definition set out in 2018. A multilevel logistic regression analysis was conducted to assess potential risk or protective factors. RESULTS: The analysis was performed on 22 periodontally healthy and 62 periodontally compromised patients rehabilitated with 39 and 130 implants, respectively. The 10-year prevalence of peri-implant health, peri-implant mucositis and peri-implantitis was 21.4%, 67.9% and 10.6%, respectively, whereas the 20-year prevalence was 29.8%, 47.6% and 33.3%, respectively. Non-compliant periodontally compromised patients showed a statistically significantly increased risk at 20 years of both peri-implant mucositis (odds ratio 11.1; 95% confidence interval 1.8-68.6) and peri-implantitis (bone loss and probing depth) (odds ratio 14.3; 95% confidence interval 1.8-32.9). High full-mouth plaque and bleeding scores were associated with higher odds of both peri-implant mucositis and peri-implantitis. CONCLUSIONS: Peri-implant diseases were prevalent in patients rehabilitated with dental implants and followed up for a period of 20 years. History of periodontal disease and a lack of compliance with a tailored supportive periodontal care programme were identified as risk factors for peri-implant diseases.

The working angle in low-abrasive air polishing has an influence on gingival damage-an ex vivo porcine model.

OBJECTIVES: To investigate the influence of instrumentation angle during low-abrasive air polishing (LAA) on the oral gingiva using an ex vivo porcine model. MATERIAL AND METHODS: Six tissue samples from each of 14 porcine mandibles were randomly selected and instrumented. Two different LAA powders (glycine 25 µm, tagatose 15 µm) were investigated. An application angle of either 30-60° or 90° was selected. Gingival specimens from different mandibles served as untreated references. Gingival biopsies were examined by scanning electron microscopy and paraffin histology for tissue destruction using a five-level scale. RESULTS: LAA caused significantly less tissue damage at a 90° angle than at a 30-60° angle. This effect was seen in both the glycine-based powder arms (p = 0.002, p = 0.046) and the tagatose-based powder arms (p = 0.003, p = 0.011). However, at identical working angles, the two powders did not show significant differences in terms of gingival erosion (p = 0.79 and p = 0.57; p = 0.91 and p = 0.78, respectively). CONCLUSIONS: LAA may cause less tissue damage at an application angle of 90°. Consequently, it seems advisable to air-polish the soft tissue as perpendicularly as possible. Additionally, glycine and tagatose LAA powders do not seem to differ in concern of soft tissue damage. CLINICAL RELEVANCE: Within the limitations of this ex vivo animal model, this study argues for an application that is as close as possible to the 90° angle intending to minimize soft tissue damage. Manufacturer specifications, however, mainly request applications deviating from the right angle. In order to work in interdental areas using LAA safely, the use of subgingival nozzles might be considered.

Clinical and radiographic outcomes of implant-supported zirconia fixed dental prostheses with cantilever extension: A proof-of-principle study with a follow-up of at least 1 year.

OBJECTIVES: To test the reliability of full zirconia implant-supported fixed dental prostheses with cantilever extension (FDPCs) after at least 1 year of function. MATERIALS AND METHODS: Thirty-five patients in need of implant-supported single unit crowns (SUC) and FDPCs in posterior areas were enrolled. After implant placement, patients were rehabilitated with screw-retained full-zirconia FDPCs. Implant survival rate, pocket probing depth (PPD), presence/absence of bleeding on probing (BoP), and presence/absence of mechanical/technical complications were recorded. Mesial and distal radiographic marginal bone levels (mBLs) from baseline (i.e., recall appointment 3-6 months after implant loading [T0]) to the follow-up examination (i.e., latest recall appointment after at least 12 months after T0 [T1]), were calculated. RESULTS: Thirty patients with 34 FDPCs (31 SUCs and 3 FDPs) supported by 37 implants were available for analysis after a mean loading time of 2.6 ± 1.5 years (range: 13-87 months). No implants were lost. MBLs and mean PPD values did not change statistically significantly from T0 to T1 from 0.92 mm ± 0.42 to 0.96 mm ± 0.38 (95% CI: -0.07/0.17; p = .418) and from 2.99 mm ± 0.70 to 3.27 mm ± 0.71 (95% CI: -0.11/0.68; p = .25) respectively. Peri-implant mucositis was diagnosed in 22 cases. Screw-loosening and zirconia chipping occurred 1× in 4 patients. CONCLUSION: Within the limitations of the present proof-of-principle study, the use of full-zirconia FDPCs in posterior areas seems a valid and safe short-term treatment option.

Histological evaluation following treatment of recession-type defects with coronally advanced flap and a novel human recombinant amelogenin.

OBJECTIVES: To histologically evaluate the effects of a novel human recombinant amelogenin (rAmelX) on periodontal wound healing / regeneration in recession-type defects. MATERIALS AND METHODS: A total of 17 gingival recession-type defects were surgically created in the maxilla of three minipigs. The defects were randomly treated with a coronally advanced flap (CAF) and either rAmelX (test), or a CAF and placebo (control). At three months following reconstructive surgery, the animals were euthanized, and the healing outcomes histologically evaluated. RESULTS: The test group yielded statistically significantly (p = 0.047) greater formation of cementum with inserting collagen fibers compared with the control group (i.e., 4.38 mm ± 0.36 mm vs. 3.48 mm ± 1.13 mm). Bone formation measured 2.15 mm ± 0.8 mm in the test group and 2.24 mm ± 1.23 mm in the control group, respectively, without a statistically significant difference (p = 0.94). CONCLUSIONS: The present data have provided for the first-time evidence for the potential of rAmelX to promote regeneration of periodontal ligament and root cementum in recession-type defects, thus warranting further preclinical and clinical testing. CLINICAL RELEVANCE: The present results set the basis for the potential clinical application of rAmelX in reconstructive periodontal surgery.

Clinical periodontal diagnosis.

Periodontal diseases include pathological conditions elicited by the presence of bacterial biofilms leading to a host response. In the diagnostic process, clinical signs such as bleeding on probing, development of periodontal pockets and gingival recessions, furcation involvement and presence of radiographic bone loss should be assessed prior to periodontal therapy, following active therapy, and during long-term supportive care. In addition, patient-reported outcomes such as increased tooth mobility, migration, and tilting should also be considered. More important to the patient, however, is the fact that assessment of signs of periodontal diseases must be followed by an appropriate treatment plan. Furthermore, it should be realized that clinical and radiographic periodontal diagnosis is based on signs which may not reflect the presence of active disease but rather represent the sequelae of a previous bacterial challenge. Hence, the aim of the present review is to provide a summary of clinical and radiographic diagnostic criteria required to classify patients with periodontal health or disease.

Marginal bone level changes around dental implants with one or two adjacent teeth - A clinical and radiographic retrospective study with a follow-up of at least 10 years.

AIM: To compare mean bone level (mBL) changes around dental implants with one or two adjacent teeth after a function time of ≥10 years. MATERIALS AND METHODS: One hundred thirty three periodontally compromised patients (PCPs) with 551 implants enrolled in supportive periodontal care (SPC) were screened. Implants were categorized either into group TIT (tooth-implant-tooth) or into group TIG (tooth-implant-gap). MBL changes from delivery of restoration (i.e., baseline) to follow-up were calculated in millimeters and compared between implants and adjacent teeth. Survival rates and the need for surgical interventions during SPC were recorded. RESULTS: Eighty seven patients with 142 implants were re-evaluated after a mean observation time of 14.5 ± 3.5 years. The mBL at mesial implant sites in the TIT group increased -0.07 ± 0.92 mm and decreased in the TIG group 0.52 ± 1.34 mm, respectively (95% CI: 0.04/1.14, p = .037). At distal implant sites, the mBL in the TIT group increased -0.08 ± 0.84 mm and decreased 0.03 ± 0.87 in the TIG group, respectively (95% CI: -0.20/0.42, p = .48). The overall implant loss rate was 3.5% (n = 5; 2 TIT, 3 TIG), without a statistically significant difference between the two groups (95% CI: 0.18/7.07, p = .892). Tooth loss rates (TIT: 12.3%, TIG: 12.3%) were not statistically significantly different (OR = 1.00, p = .989). CONCLUSION: High tooth and implant survival rates were observed in PCPs. The presence of one or two adjacent teeth seemed to have no impact on marginal bone level changes.

Spontaneous regeneration of keratinized tissue at implants and teeth.

AIM: To investigate the spontaneous regeneration of the implanto-mucosal and dento-gingival unit after complete removal of keratinized tissue (KT). MATERIALS AND METHODS: One hemi-mandible per dog (n = 4) was allocated to receive three dental implants (test sites, premolar region), whereas three premolars on the contralateral side were controls. After osseointegration, the entire KT (buccal + lingual) was surgically excised on all test and control sites, leaving the bone exposed. Clinical measurements were performed before excision (T0 ) and after 12 weeks (T1 ). Following healing, the animals were euthanized, and the specimens were histologically processed. Descriptive statistical analyses were performed. RESULTS: Clinical measurements revealed that at T1 , on all teeth, a band of KT was spontaneously regenerated (mean width: 2.60 ± 0.66 mm), whereas on implants, KT was detected only occasionally at mesial or distal but not at buccal sites (mean total: 0.35 ± 0.53 mm; p < .0001). Histologically, spontaneous regeneration of the dento-gingival unit was evident, displaying masticatory mucosa. At the implant sites, on the other hand, the implanto-mucosal unit was characterized by a non-keratinized epithelium and elastic fibres, indicating the characteristics encountered in alveolar mucosa. CONCLUSION: After excision of KT at implant sites, the spontaneous regeneration of the soft tissue is characterized by a non-keratinized epithelium typical for alveolar mucosa, while at tooth sites the spontaneous regeneration was characterized by soft tissue resembling gingiva.

Healing of intrabony defects using a novel human recombinant amelogenin: a preclinical study.

OBJECTIVE: To histologically evaluate the effects of a novel human recombinant amelogenin (rAmelX) on periodontal wound healing/regeneration in intrabony defects. METHOD AND MATERIALS: Intrabony defects were surgically created in the mandible of three minipigs. Twelve defects were randomly treated with either rAmelX and carrier (test group) or with the carrier only (control group). At 3 months following reconstructive surgery, the animals were euthanized, and the tissues histologically processed. Thereafter, descriptive histology, histometry, and statistical analyses were performed. RESULTS: Postoperative clinical healing was uneventful. At the defect level, no adverse reactions (eg, suppuration, abscess formation, unusual inflammatory reaction) were observed with a good biocompatibility of the tested products. The test group yielded higher values for new cementum formation (4.81 ± 1.17 mm) compared to the control group (4.39 ± 1.71 mm) without reaching statistical significance (P = .937). Moreover, regrowth of new bone was greater in the test compared to the control group (3.51 mm and 2.97 mm, respectively, P = .309). CONCLUSIONS: The present results provided for the first-time histologic evidence for periodontal regeneration following the use of rAmelX in intrabony defects, thus pointing to the potential of this novel recombinant amelogenin as a possible alternative to regenerative materials from animal origins.

Sequential osseointegration of a novel implant system based on 3D printing in comparison with conventional titanium implants.

OBJECTIVES: To evaluate the sequential osseointegration of a novel titanium implant system based on a 3D printing technology in comparison with conventional titanium implants. MATERIAL AND METHODS: Two novel titanium implants based on 3D printing were tested in the mandible of eight Beagle dogs. As a control, two different commercially available titanium implants were used. The implants were staged to accommodate healing periods of 2 and 6 weeks. The primary outcome variable was bone-to-implant contact (BIC) in non-decalcified tissue sections and micro-CT analysis. RESULTS: Histomorphometrically, the proportions of tissues adjacent to the implant surfaces were similar for all implants, whereas the BIC percentage of new mineralized bone was greater for the control implants after both 2 and 6 weeks (p < .05). Micro-CT analysis revealed increasing osseous volume and BIC from 2 to 6 weeks. In contrast to the histomorphometry, the BIC evaluation with the micro-CT data revealed a significantly higher BIC for the two test implants compared with controls (p < .001). The analysis of the total implant surface area disclosed a value that was approximately double as high for the test compared to the control implants. CONCLUSIONS: The novel titanium implant system based on 3D printing yielded values for osseointegration that were adequate and satisfactory. The higher percentage of new mineralized bone in the control implants is explained by the fact of a completely different three-dimensional surface area.

Implant-supported fixed dental prostheses with cantilever extensions: State of the art and future perspectives.

Partial fixed dental prostheses supported by dental implants have become a reliable long-term treatment option. Nevertheless, the replacement of two adjacent missing teeth, irrespective of location, still represents a clinical challenge. To overcome this, the use of fixed dental prostheses with cantilever extensions has gained popularity with a view to limiting morbidity, reducing costs and avoiding major surgical interventions prior to implant placement. The present review summarises the level of evidence for the use of fixed dental prostheses with cantilever extensions both in the posterior and anterior regions and indicates the advantages and disadvantages of each treatment, focusing on available medium- to long-term outcomes.

Peri-implantitis as the consequence of errors in implant therapy.

Peri-implantitis is a plaque-associated pathologic condition occurring in tissues around dental implants, characterized by inflammation in the peri-implant mucosa and subsequent progressive loss of supporting bone. It is a highly prevalent disease, as extensively estimated by large-population, cross-sectional studies. As peri-implant diseases represent opportunistic infections, it is reasonable to assume that nonideal conditions, local and/or general, may favor the progression of peri-implant inflammation. Some of these conditions could be a result of poor planning and/or inadequate execution of any step of the entire process treatment. This article describes the major possible factors in implant therapy that may lead to peri-implantitis. For some of these (ie, inappropriate patient selection, insufficient periodontal therapy, lack of diagnosis and management of peri-implant mucositis, erratic supportive peri-implant/periodontal therapy) there is a good level of evidence, whereas for others (ie, wrong implant placement, poor postoperative care, inadequate prosthetic reconstruction, lack of assessment and management of peri-implant soft-tissue deficiencies) there is little scientific evidence. More research is therefore needed to clearly identify the errors and/or complications possibly leading to peri-implantitis, particularly over the long term.

Radiographic angle width as predictor of clinical outcomes following regenerative periodontal therapy with enamel matrix derivative: a retrospective cohort study with a mean follow-up of at least 10 years.

OBJECTIVES: To assess the association between the baseline radiographic defect angle and the long-term clinical outcomes following periodontal regenerative therapy with enamel matrix derivative (EMD). METHOD AND MATERIALS: Baseline periapical radiographs obtained from a cohort of patients treated with periodontal regenerative therapy were digitized and the radiographic angle width between the root surface and the bony wall of the adjacent intraosseous defect was calculated and reported (in degrees). Changes in pocket probing depth (PD) and clinical attachment level (CAL) were assessed and reported (in mm). Clinical outcomes were evaluated at baseline (T0), 6 months following therapy (T1), and at the latest follow-up (T2). RESULTS: Thirty-eight defects in 26 patients enrolled in supportive periodontal care for a mean period of 10.4 years (range 8.0 to 15.5 years) were available for analysis. The mean PD change between T0 and T2 was 2.33 ± 1.66 mm at teeth with a defect angle width < 20 degrees and 0.86 ± 1.66 mm at teeth with a defect angle width > 30 degrees (P = .021). When the baseline radiographic angle width was < 20 degrees the probability of obtaining a CAL gain > 3 mm was 1.5-times higher (95% CI 0.19 to 13.8) at T1 and 2.5-times higher (95% CI 0.40 to 15.6) at T2 compared with defects with a radiographic angle width > 30 degrees. CONCLUSION: Within their limitations, these results indicate that pretherapeutic measurement of the radiographic defect angle width might provide relevant information on the short-/long-term clinical outcomes following regenerative periodontal therapy with EMD.

Influence of loading and grafting on hard- and soft-tissue healing at immediately placed implants: An experimental study in minipigs.

AIM: To histologically evaluate the influence of (1) loading and (2) grafting on osseointegration and peri-implant soft-tissue healing at immediately placed, self-cutting progressive tissue-level implants (TLX) in a minipig model. MATERIALS AND METHODS: TLX implants (n = 56) were immediately placed following the extraction of the mandibular first and second premolars, bilaterally, in a total of n = 14 minipigs. In each animal, the implant sites were allocated to the following four groups: (1) unloaded with simultaneous grafting using a bovine bone mineral; (2) unloaded without grafting; (3) loaded with simultaneous grafting; and (4) loaded without grafting. Histomorphometric assessments at 4 and 12 weeks (n = 7 animals each) included primary (i.e., bone-to-implant contact [BIC]) and secondary outcome measures (e.g., first BIC [fBIC], junctional epithelium length [JE], connective tissue contact length [CTC], biological width [BW = JE + CTC]). RESULTS: At 4 weeks, mean BIC values ranged from 74.5 ± 11.6% in Group 2 to 83.8 ± 13.3% in Group 1, and, at 12 weeks, from 75.5% ± 7.9% in Group 2 to 79.9 ± 8.6% in Group 1. Multivariate linear mixed regression did not reveal any associations between BIC and implant loading or grafting at 4 and 12 weeks. At 12 weeks, significantly higher fBIC values were noted in Group 2 when compared with Group 1. All groups showed comparable JE, CTC, and BW values. CONCLUSIONS: Implant loading and grafting had no major effects on osseointegration and peri-implant soft tissue healing at TLX implants.

Physiopathology of peri-implant diseases.

BACKGROUND: Peri-implant health is characterized by the absence of clinical signs of soft tissue inflammation. Peri-implant diseases are initiated by the presence of bacterial biofilms and share a similar etiology as that involved in the onset of periodontal diseases. PURPOSE: To summarize available evidence on the physiopathology of peri-implant diseases with emphasis on similarities and differences with periodontal diseases. MATERIALS AND METHODS: Evidence on the biologic mechanisms involved in the pathogenesis of peri-implant mucositis and peri-implantitis were explored in the recent scientific literature. RESULTS: Findings of studies in animals and in humans indicate that experimental peri-implant mucositis leads to a larger inflammatory connective tissue infiltrate and to a higher frequency of bleeding sites around implants compared with teeth. Tissue destruction at experimental peri-implantitis sites is more pronounced compared with that at experimental periodontitis sites. Although human periodontitis and peri-implantitis lesions share similarities with respect to etiology and clinical features, they represent distinct entities from a physiopathologic point of view. CONCLUSIONS: Diagnosis of peri-implant health requires a clinical examination to confirm absence of peri-implant soft tissue inflammation. In order to make a correct diagnosis and select the appropriate therapeutic steps to manage peri-implant diseases, knowledge of their pathogenetic mechanisms is required.

Clinical outcomes of dental implants in patients with and without history of periodontitis: A 20-year prospective study.

AIM: To present the 20-year clinical outcomes of tissue-level implants in partially edentulous patients previously treated for periodontitis and in periodontally healthy patients (PHP). MATERIAL AND METHODS: The original population consisted of 149 partially edentulous patients consecutively enrolled in a private specialist practice and divided into three groups: PHP, moderately periodontally compromised patients (mPCP) and severely PCP (sPCP). After successful completion of periodontal/implant therapy, patients were enrolled in an individualized supportive periodontal care (SPC) programme. RESULTS: Eighty-four patients rehabilitated with 172 implants reached the 20-year examination. During the observation time, 12 implants were removed (i.e., 11 due to biological complications and 1 due to implant fracture), leading to an overall implant survival rate of 93% (i.e., 94.9% for PHP, 91.8% for mPCP and 93.1% for sPCP [p = .29]). At 20 years, PCP compliant with SPC did not present with significantly higher odds of implant loss compared with PHP compliant with SPC (p > .05). Conversely, PCP not compliant with SPC experienced implant loss with odds ratio of 14.59 (1.30-164.29, p = .03). CONCLUSIONS: Tissue-level implants, placed after comprehensive periodontal therapy and SPC, yield favourable long-term results. However, patients with a history of periodontitis and non-compliant with SPC are at higher risk of biological complications and implant loss.