The adjunctive effect of a resorbable membrane to a xenogeneic bone replacement graft in the reconstructive surgical therapy of peri-implantitis: A randomized clinical trial.

AIM: To evaluate the potential adjunctive effect of a resorbable collagen membrane covering a xenogeneic bone replacement graft in the reconstructive surgical therapy of peri-implantitis. MATERIALS AND METHODS: Forty-three patients (43 implants) diagnosed with peri-implantitis associated with intra-bony defects were treated with a surgical reconstructive approach that included a xenogeneic bone substitute material. Additionally, resorbable collagen membranes were placed over the grafting material at sites randomly allocated to the test group; conversely, no membranes were placed in the control group. Clinical outcomes, namely probing pocket depth (PPD), bleeding and suppuration on probing (BoP and SoP), marginal mucosal level (REC) and keratinized mucosa width (KMW), were recorded at baseline and 6 and 12 months after surgery. Radiographic marginal bone levels (MBLs) and patient-reported outcomes (PROs) were assessed at baseline and 12 months. A composite outcome (success) was evaluated at 12 months, which included the absence of BoP/SoP, PPD ≤5 mm and reduction of buccal marginal mucosal level (buccal REC) of ≤1 mm. RESULTS: At 12 months, no implants were lost and treatment success was observed at 36.8% and 45.0% of implants in the test and control groups, respectively (p = .61). Similarly, there were no significant differences between groups in terms of changes of PPD, BoP/SoP, KMW, MBL or buccal REC. Post-surgical complications were observed in the test group only (e.g., soft tissue dehiscence, exposure of particulate bone graft and/or resorbable membrane). Longer surgical times (~10 min; p < .05) and higher levels of self-reported pain at 2 weeks (p < .01) were observed in the test group. CONCLUSIONS: This study failed to demonstrate the presence of added clinical or radiographic benefits of the use of a resorbable membrane to cover a bone substitute material within the reconstructive surgical therapy of peri-implantitis associated with intra-bony defects.

Factors influencing outcomes of surgical therapy of peri-implantitis: A secondary analysis of 1-year results from a randomized clinical study.

AIM: To identify predictors of treatment outcomes following surgical therapy of peri-implantitis. MATERIALS AND METHODS: We performed a secondary analysis of data from a randomized controlled trial (RCT) comparing access flap with or without bone replacement graft. Outcomes at 12 months were probing pocket depth (PPD), bleeding on probing (BOP), soft-tissue recession (REC) and marginal bone level (MBL) change. Multilevel regression analyses were used to identify predictors. We also built an explanatory model for residual signs of inflammation. RESULTS: Baseline PPD was the most relevant predictor, showing positive associations with final PPD, REC and MBL gain, and negative association with probability of pocket closure. Smokers presented higher residual PPD. Absence of keratinized mucosa at baseline increased the probability of BOP but was otherwise not indicative of outcomes. Plaque at 6 weeks was detrimental in terms of residual PPD and BOP. Treatment allocation had an effect on REC. Final BOP was explained by residual PPD ≥6 mm and plaque at more than two sites. CONCLUSIONS: Baseline PPD was the most relevant predictor of the outcomes of surgical therapy of peri-implantitis. Pocket closure should be a primary goal of treatment. Bone replacement grafts may be indicated in aesthetically demanding cases to reduce soft-tissue recession. The importance of smoking cessation and patient-performed plaque control is also underlined.

Complications in sinus lifting procedures: Classification and management.

Open and closed sinus lifting procedures are predictable methods to augment the bone needed for appropriate implant placement in the posterior maxilla in cases where available bone is limited. However, these techniques may give rise to complications and associated comorbidities. In the case of open sinus lifting, perforation of the Schneiderian membrane during osteotomy is the most common complication, with an incidence rate of around 20%-25%. Apart from those complications associated with oral surgery in general (such as swelling or hematoma), there are specific complications of open sinus lifting procedures that may arise less frequently (chronic rhinosinusitis, hemorrhage, or ostium blockage by overfilling) but which may nevertheless compromise the viability of the graft and/or the implants and cause substantial discomfort to the patient. Closed sinus lifting is a less invasive approach that allows transcrestal placement of the implants in cases where there is sufficient residual bone height. However, it may also be associated with specific complications, including membrane perforation, benign paroxysmal positional vertigo, and implant displacement to the sinus cavity. New technologies have been proposed to reduce these complications and comorbidities associated with conventional sinus lifting procedures, such as the use of piezoelectric devices and hydraulic sinus lift or reamer burs. The evidence supporting their effectiveness and safety, however, is still lacking. A detailed medical history together with a thorough radiographic and clinical examination are essential prior to any kind of bone regenerative augmentation involving the maxillary sinus. Moreover, it is recommended to employ the most appropriate surgical technique for the specific characteristics of the case and, at the same time, accommodating the experience and skills of the surgeon.

Complications in bone-grafting procedures: Classification and management.

Bone-regenerative interventions aiming to restore deficient alveolar ridges, such as the use of block grafts or through the application of guided bone-regeneration principles, have reported positive outcomes in the published scientific literature. These interventions, however, are invasive, and hence, intraoperative and/or postoperative complications may occur. The types of complications and their severity may vary from the exposure of the biomaterial (membrane or graft) to postsurgical infections, neurosensorial disturbances, occurrence of hemorrhage, and pain, etc. The aim of the present narrative review was to search the available scientific evidence concerning the incidence of these complications, their effect on treatment outcomes, their clinical management and, finally, strategies aimed at prevention. Exposure of the barrier membrane or the block graft is the most common complication associated with oral regenerative interventions. To manage these complications, depending on the extent of the exposure and the presence or absence of concomitant infections, therapeutic measures may vary, from the topical application of antiseptics to the removal of the barrier membrane or the block graft. Regardless of their treatment, the occurrence of these complications has been associated with patient selection, with compliant patients (eg, nonsmokers) having a lower reported incidence of complications. Similarly, surgical factors such as correct flap elevation and a tensionless closure are of obvious importance. Finally, to prevent the incidence of complications, it appears prudent to utilize whenever possible less invasive surgical interventions.

Efficacy of keratinized mucosal augmentation with a collagen matrix concomitant to the surgical treatment of peri-implantitis: A dual-center randomized clinical trial.

AIM: The aim of this study was to evaluate the efficacy of a xenogeneic collagen matrix to augment the width of keratinized mucosa (KM), concomitantly to the surgical treatment of peri-implantitis, when compared to the use of an autologous soft tissue graft. MATERIAL AND METHODS: In this 12-month parallel-arm randomized controlled clinical trial, patients with peri-implantitis were randomly assigned, one month after non-surgical therapy, to surgical resective treatment of peri-implantitis consisting on an apically positioned flap (APF) in combination with a KM augmentation procedure, either with an autologous free gingival graft (FGG) or a collagen matrix (CM). Primary outcomes were the increase in the width of KM and probing pocket depth (PPD) reduction at 12 months. As secondary outcomes, peri-implant radiographic and patient-reported outcomes were assessed. RESULTS: The intention-to-treat population consisted of 49 subjects, assigned to either the APF + FGG (n = 23) or APF + CM (n = 26) group. PPDs were reduced by 1.6 mm (SD 1.0) and 1.7 mm (SD 1.2), respectively, being these differences non statistically significant (p = .782). However, the increase in KM was significantly higher in the APF + FGG compared with APF + CM (2.5 mm [SD 1.6] vs. 1.6 mm [SD 1.2], respectively (p = .033). CONCLUSION: The tested surgical modalities resulted in similar improvements of the clinical parameters. Both free gingival graft and collagen matrix significantly increased the peri-implant keratinized mucosa, but this KM gain was significantly higher with the free gingival graft. Use of CM, however, was better appreciated by the patients, in terms of pain perception and analgesic consumption, although the surgical time was similar.

Reconstructive surgical therapy of peri-implantitis: A multicenter randomized controlled clinical trial.

OBJECTIVE: To evaluate the potential benefit of the use of a bone substitute material in the reconstructive surgical therapy of peri-implantitis. METHODS: In this multicenter randomized clinical trial, 138 patients (147 implants) with peri-implantitis were treated surgically, randomized by coin toss to either a control (access flap surgery) or a test group (reconstructive surgery using bone substitute material). Clinical assessments, including probing pocket depth (PPD), bleeding and suppuration on probing (BOP & SOP) as well as soft tissue recession (REC), were recorded at baseline, 6 and 12 months. Marginal bone levels (MBL), measured on intra-oral radiographs, and patient-reported outcomes (PROs) were recorded at baseline and 12 months. No blinding to group allocation was performed. The primary outcome at 12 months was a composite measure including (i) implant not lost, (ii) absence of BOP/SOP at all aspects, (iii) PPD ≤5 mm at all aspects and (iv) ≤1 mm recession of mucosal margin on the buccal aspect of the implant. Secondary outcomes included (i) changes of MBL, (ii) changes of PPD, BOP%, and buccal KM, (iii) buccal REC and (iv) patient-reported outcomes. RESULTS: During follow-up, four implants (one in the test group, three in the control group) in four patients were removed due to disease progression. At 12 months, a total of 69 implants in the test and 68 implants in the control group were examined. Thus, 16.4% and 13.5% of implants in the test and control group, respectively, met all predefined criteria of the composite outcome. PPD reduction and MBL gain were 3.7 mm and about 1.0 mm in both groups. Reduction in mean BOP% varied between 45% (test) and 50% (control), without significant differences between groups. Buccal REC was less pronounced in the test group (M = 0.7, SD = 0.9 mm) when compared to controls (M = 1.1, SD = 1.5 mm). PROs were favorable in both groups without significant differences. One case of allergic reaction to the antibiotic therapy was recorded. No other adverse events were noted. CONCLUSIONS: Surgical therapy of peri-implantitis effectively improved the clinical and radiographic status at 12 months. While the use of a bone substitute material did not improve reductions of PPD and BOP, buccal REC was less pronounced in the test group. Patient satisfaction was high in both groups.

Effect of peri-implant mucosal thickness on esthetic outcomes and the efficacy of soft tissue augmentation procedures: Consensus report of group 2 of the SEPA/DGI/OF workshop.

OBJECTIVES: The aim of this study was to comprehensively assess the literature in terms of the effect of peri-implant mucosal thickness on esthetic outcomes and the efficacy of soft tissue augmentation procedures to increase the mucosal thickness with autogenous grafts or soft tissue substitutes. MATERIAL AND METHODS: Two systematic reviews (SR) were performed prior to the consensus meeting to assess the following questions. Review 1, focused question: In systemically healthy patients with an implant-supported fixed prosthesis, what is the influence of thin as compared to thick peri-implant mucosa on esthetic outcomes? Review 2, focused question 1: In systemically healthy humans with at least one dental implant (immediate or staged implant), what is the efficacy of connective tissue graft (CTG), as compared to absence of a soft tissue grafting procedure, in terms of gain in peri-implant soft tissue thickness (STT) reported by randomized controlled clinical trials (RCTs) or controlled clinical trials (CCTs)? Review 2, focused question 2: In systemically healthy humans with at least one dental implant (immediate or staged implant), what is the efficacy of CTG, as compared to soft tissue substitutes, in terms of gain in peri-implant STT reported by RCTs or CCTs? The outcomes of the two SRs, the consensus statements, the clinical implications, and the research recommendations were discussed and subsequently approved at the consensus meeting during the group and plenary sessions. CONCLUSIONS: There was a tendency of superior esthetic outcomes in the presence of a thick mucosa. The connective tissue graft remains the standard of care in terms of increasing mucosa thickness.

Efficacy of reconstructive surgical therapy at peri-implantitis-related bone defects. A systematic review and meta-analysis.

OBJECTIVES: The present systematic review aimed at evaluating the efficacy of reconstructive surgical therapy at peri-implantitis-related bone defects. METHODS: Studies reporting on outcomes of reconstructive surgery at peri-implantitis-related bone defects at 12 months were identified through an electronic search. Following data extraction, two different sets of meta-analyses were performed. Primarily, controlled studies were used to evaluate the potential benefit of reconstructive surgical therapy over controls. Secondly, overall outcome of reconstructive surgical therapy was assessed by comparing baseline values with outcomes at 12 months. Results were expressed as weighted mean differences (WMD) or risk ratios (RR). Heterogeneity was described by I2 and prediction intervals. RESULTS: The potential benefit of reconstructive techniques over control procedures was evaluated in three studies, representing a total of 116 implants. Altogether, 16 studies reported on the outcome of reconstructive measures at 12 months after surgery. The meta-analyses identified a larger improvement in marginal bone levels (MBL, WMD = 1.7 mm) and in defect fill (WMD = 57%) for test procedures, but found no differences for clinical measures (reduction of probing depth (PD) and bleeding on probing (BOP). Changes of clinical attachment and soft tissue levels were not considered. In terms of overall outcome, therapy resulted in improved MBL (WMD = 2.0 mm) and CAL (WMD = 1.8 mm), in recession (WMD = 0.7 mm), in reduced PD (WMD = 2.8 mm) and in reduced BOP (Implants: RR = 0.4/Sites: RR = 0.2). None of the included studies addressed patient-reported outcome measures. CONCLUSIONS: The available evidence on reconstructive therapy at peri-implantitis-related defects is limited by (a) the low number of controlled studies, (b) the lack of controlled studies for commonly used procedures, (c) the heterogeneity between studies and (d) the choice of outcome measures. A high variability for predicted outcomes at 12 months was noted. The interpretation of the demonstrated larger MBL gain for test procedures is difficult as graft material may not be distinguishable from newly formed bone. Potential aesthetic and patient-reported advantages remain to be demonstrated.

Regeneration of alveolar ridge defects. Consensus report of group 4 of the 15th European Workshop on Periodontology on Bone Regeneration.

BACKGROUND AND AIMS: Bone augmentation procedures to enable dental implant placement are frequently performed. The remit of this working group was to evaluate the current evidence on the efficacy of regenerative measures for the reconstruction of alveolar ridge defects. MATERIAL AND METHODS: The discussions were based on four systematic reviews focusing on lateral bone augmentation with implant placement at a later stage, vertical bone augmentation, reconstructive treatment of peri-implantitis associated defects, and long-term results of lateral window sinus augmentation procedures. RESULTS: A substantial body of evidence supports lateral bone augmentation prior to implant placement as a predictable procedure in order to gain sufficient ridge width for implant placement. Also, vertical ridge augmentation procedures were in many studies shown to be effective in treating deficient alveolar ridges to allow for dental implant placement. However, for both procedures the rate of associated complications was high. The adjunctive benefit of reconstructive measures for the treatment of peri-implantitis-related bone defects has only been assessed in a few RCTs. Meta-analyses demonstrated a benefit with regard to radiographic bone gain but not for clinical outcomes. Lateral window sinus floor augmentation was shown to be a reliable procedure in the long term for the partially and fully edentulous maxilla. CONCLUSIONS: The evaluated bone augmentation procedures were proven to be effective for the reconstruction of alveolar ridge defects. However, some procedures are demanding and bear a higher risk for post-operative complications.

Safety and performance of a novel collagenated xenogeneic bone block for lateral alveolar crest augmentation for staged implant placement.

OBJECTIVES: To evaluate the performance and safety of placing a collagenated xenogeneic bone block (CXBB) graft for the lateral bone augmentation of the alveolar crest prior to implant placement. MATERIAL & METHODS: In patients with single or multiple tooth gaps and a severe horizontal collapse of the alveolar ridge, a ridge augmentation procedure was performed using CXBB fixated with osteosynthesis screws to the atrophic bone crest and complemented with deproteinized bovine bone mineral particles (DBBM) and a native bilayer collagen membrane (NBCM). Patients were examined with CBCT prior to and 24 weeks after the augmentation. Twenty-six weeks postoperatively, a re-entry procedure was performed to evaluate the bone width and availability for adequate implant placement. RESULTS: Fifteen patients received 28 CXBB, and in 13 patients, a re-entry procedure was performed. Eleven patients (84.6%) gained enough bone volume for implant insertion without additional contouring or secondary bone augmentation. The mean crest width at baseline was 2.83 mm (SD 0.57), and the mean crest width at re-entry was 6.90 mm (SD 1.22), with a mean ridge width increase of 4.12 mm (SD 1.32). Soft tissue dehiscence occurred during the follow-up in 5 of 14 patients (35.7%) at various time points. In addition, there was a high incidence of early implant loss (30.8% [patient-based]). CONCLUSIONS: CXBB achieved significant horizontal crestal width gains allowing a secondary implant placement in the majority of the patients. However, the occurrence of soft tissue dehiscence may notably affect the outcome of the subsequent implant therapy.

Prevention and control of dental caries and periodontal diseases at individual and population level: consensus report of group 3 of joint EFP/ORCA workshop on the boundaries between caries and periodontal diseases.

BACKGROUND: The non-communicable diseases dental caries and periodontal diseases pose an enormous burden on mankind. The dental biofilm is a major biological determinant common to the development of both diseases, and they share common risk factors and social determinants, important for their prevention and control. The remit of this working group was to review the current state of knowledge on epidemiology, socio-behavioural aspects as well as plaque control with regard to dental caries and periodontal diseases. METHODS: Discussions were informed by three systematic reviews on (i) the global burden of dental caries and periodontitis; (ii) socio-behavioural aspects in the prevention and control of dental caries and periodontal diseases at an individual and population level; and (iii) mechanical and chemical plaque control in the simultaneous management of gingivitis and dental caries. This consensus report is based on the outcomes of these systematic reviews and on expert opinion of the participants. RESULTS: Key findings included the following: (i) prevalence and experience of dental caries has decreased in many regions in all age groups over the last three decades; however, not all societal groups have benefitted equally from this decline; (ii) although some studies have indicated a possible decline in periodontitis prevalence, there is insufficient evidence to conclude that prevalence has changed over recent decades; (iii) because of global population growth and increased tooth retention, the number of people affected by dental caries and periodontitis has grown substantially, increasing the total burden of these diseases globally (by 37% for untreated caries and by 67% for severe periodontitis) as estimated between 1990 and 2013, with high global economic impact; (iv) there is robust evidence for an association of low socio-economic status with a higher risk of having dental caries/caries experience and also with higher prevalence of periodontitis; (v) the most important behavioural factor, affecting both dental caries and periodontal diseases, is routinely performed oral hygiene with fluoride; (vi) population-based interventions address behavioural factors to control dental caries and periodontitis through legislation (antismoking, reduced sugar content in foods and drinks), restrictions (taxes on sugar and tobacco) guidelines and campaigns; however, their efficacy remains to be evaluated; (vii) psychological approaches aimed at changing behaviour may improve the effectiveness of oral health education; (viii) different preventive strategies have proven to be effective during the course of life; (ix) management of both dental caries and gingivitis relies heavily on efficient self-performed oral hygiene, that is toothbrushing with a fluoride-containing toothpaste and interdental cleaning; (x) professional tooth cleaning, oral hygiene instruction and motivation, dietary advice and fluoride application are effective in managing dental caries and gingivitis. CONCLUSION: The prevention and control of dental caries and periodontal diseases and the prevention of ultimate tooth loss is a lifelong commitment employing population- and individual-based interventions.

Microbiological effects and recolonization patterns after adjunctive subgingival debridement with Er:YAG laser.

OBJECTIVES: The objective of this study was to assess the microbiological effects and recolonization patterns after non-surgical periodontal treatment protocol based on the adjunctive use of erbium-doped yttrium aluminium garnet (Er:YAG) laser. MATERIAL AND METHODS: Patients diagnosed with chronic periodontitis were randomly assigned to two different treatment protocols: test, full-mouth subgingival ultrasonic instrumentation followed by Er-YAG laser application 1 week later to sites with initial probing pocket depth ≥4.5 mm; and control, full-mouth ultrasonic subgingival instrumentation within 1 week. Clinical (at sampled sites) and microbiological (culture-based) parameters were recorded at baseline and 3 and 12 months. Microbiological variables included total counts, frequency of detection, proportions and counts of target species. RESULTS: Results from 19 test and 21 control patients were compared. Minor changes were observed for total colony-forming units, with no differences between groups. For the frequency of detection, a limited and similar impact in both groups was observed for the most prevalent (over 80 %) periodontal pathogens (Porphyromonas gingivalis, Prevotella intermedia, Fusobacterium nucleatum). For proportions, reductions in P. gingivalis occurred at 3 months, both in the test and control groups (from 16.3 to 10 % and 16 to 14.8 %, respectively), although these differences were not statistically significant. At 12 months, the test group showed a statistically significant greater reduction in probing depth for the sampled sites. CONCLUSIONS: The adjunctive use of Er:YAG laser when compared with conventional ultrasonic debridement did not provide a microbiological added benefit. CLINICAL RELEVANCE: Even though some clinical benefits with the adjunctive laser application were identified when comparing both treatment protocols, there were no differences in microbiological outcomes or in the bacterial recolonization patterns.

Primary prevention of peri-implantitis: managing peri-implant mucositis.

AIMS: Over the past decades, the placement of dental implants has become a routine procedure in the oral rehabilitation of fully and partially edentulous patients. However, the number of patients/implants affected by peri-implant diseases is increasing. As there are--in contrast to periodontitis--at present no established and predictable concepts for the treatment of peri-implantitis, primary prevention is of key importance. The management of peri-implant mucositis is considered as a preventive measure for the onset of peri-implantitis. Therefore, the remit of this working group was to assess the prevalence of peri-implant diseases, as well as risks for peri-implant mucositis and to evaluate measures for the management of peri-implant mucositis. METHODS: Discussions were informed by four systematic reviews on the current epidemiology of peri-implant diseases, on potential risks contributing to the development of peri-implant mucositis, and on the effect of patient and of professionally administered measures to manage peri-implant mucositis. This consensus report is based on the outcomes of these systematic reviews and on the expert opinion of the participants. RESULTS: Key findings included: (i) meta-analysis estimated a weighted mean prevalence for peri-implant mucositis of 43% (CI: 32-54%) and for peri-implantitis of 22% (CI: 14-30%); (ii) bleeding on probing is considered as key clinical measure to distinguish between peri-implant health and disease; (iii) lack of regular supportive therapy in patients with peri-implant mucositis was associated with increased risk for onset of peri-implantitis; (iv) whereas plaque accumulation has been established as aetiological factor, smoking was identified as modifiable patient-related and excess cement as local risk indicator for the development of peri-implant mucositis; (v) patient-administered mechanical plaque control (with manual or powered toothbrushes) has been shown to be an effective preventive measure; (vi) professional intervention comprising oral hygiene instructions and mechanical debridement revealed a reduction in clinical signs of inflammation; (vii) adjunctive measures (antiseptics, local and systemic antibiotics, air-abrasive devices) were not found to improve the efficacy of professionally administered plaque removal in reducing clinical signs of inflammation. CONCLUSIONS: Consensus was reached on recommendations for patients with dental implants and oral health care professionals with regard to the efficacy of measures to manage peri-implant mucositis. It was particularly emphasized that implant placement and prosthetic reconstructions need to allow proper personal cleaning, diagnosis by probing and professional plaque removal.

Factors associated with the presence of peri-implant buccal soft tissue dehiscences: A case-control study.

BACKGROUND: To identify factors associated with the presence of buccal soft tissue dehiscences (BSTD). METHODS: This cross-sectional observational study assessed 52 cases (CAS) with a minimum of 24 months of loading, with the presence of a BSTD, defined as an exposure of the prosthetic abutment, the implant neck or the implant surface in the anterior maxillae or mandible (premolar-premolar) and 52 carefully selected controls (CON) matched for age and years in function, being the only difference between groups the BSTD. Clinical parameters and radiographic findings from periapical radiographs and Cone Beam Computed Tomographies (CBCT) were analyzed to assess their association with the occurrence of BSTD using a multivariate regression model. RESULTS: The CAS had a mean keratinzed mucosa (KM) of 1.65 ± 1.31 mm, whereas in the CON KM was 3.27 ± 1.28 mm (P = 0.001). Probing depths were similar in both groups, whereas bleeding on probing and plaque scores were higher in the CAS (P = 0.001). Mean bone level scores in the CAS were 1.71 ± 1.04 mm, and 1.27 ± 1.01 mm in CON (P = 0.143). The first bone to implant contact at the buccal aspect was 4.85 ± 3.12 mm in CAS and 2.15 ± 3.44 mm in CON (P = 0.001). CAS were 1.48 ± 0.93 mm outside the alveolar envelope, whereas the CON were 0.46 ± 0.77 mm. Implants buccally positioned in the CBCT's were 34 times more likely to belong to the case group. The presence of >2 mm of KM at the time of evaluation, presence of adjacent natural teeth, cemented restorations and two-piece implants were protective factors. CONCLUSION: The bucco-palatal implant position was the most relevant factor related to the presence of BSTD.

Histomorphometric and immunohistochemical evaluation of collagen containing xenogeneic bone blocks used for lateral bone augmentation in staged implant placement.

BACKGROUND: The osteoconductive properties of collagen containing xenogeneic bone blocks (CCXBB) remain unclear. The aim of this prospective single-arm clinical study was to assess the histological outcomes of CCXBB blocks used as bone replacement grafts for lateral bone augmentation procedures. METHODS: In 15 patients with severe horizontal alveolar ridge resorption, lateral augmentation procedures were performed using CCXBB as bone replacement grafts. Twenty-six weeks postoperatively, a re-entry procedure was performed to evaluate the bone width for adequate implant placement and two histological specimens were retrieved from each patient, one being processed for ground sectioning and the other for decalcified paraffin-included sections. In non-decalcified sections, the relative proportions occupied by bone, biomaterials, and connective tissue present in the biopsies were identified. In de-calcified sections, structures and cells positive for osteopontin (OPN), tartrate-resistant acid phosphatase activity (TRAP), osteocalcin (OSC), and alkaline phosphatase (ALP) were assessed. RESULTS: Soft tissue dehiscence occurred during the follow-up in 5 out of 15 patients (33.3%). The mean crest width at baseline was 2.78 mm (SD 0.57) and the mean crest width at re-entry was 6.90 mm (SD 1.22), with a mean ridge width increase of 4.12 mm (SD 1.32). Twenty-six bone biopsies were obtained from 13 patients. Histomorphometric analysis showed a mean of 26.90% (SD 12.21) of mineralized vital bone (MVB), 21.37% (SD 7.36) of residual CCXBB, 47.13% (SD 19.15) of non-mineralized tissue, and 0.92% of DBBM. The immunohistochemical analysis revealed a large number of OPN-positive cells 8.12% (SD 4.73), a lower proportion of TRAP positive multinuclear cells 5.09% (SD 4.91), OSC-positive cells 4.09% (SD 4.34), and a limited amount of ALP positive cells 1.63% (SD 2). CONCLUSIONS: CCXBB achieved significant horizontal crestal width allowing for staged implant placement in most of the patients. In light of the histological outcomes and implant failures, special attention must be placed to prevent soft tissue dehiscence when CCXBB is used in severe atrophic alveolar crests.

Randomized controlled clinical trial comparing two dental implants with different neck configurations.

BACKGROUND: Peri-implant bone levels can vary according to the implant neck macro-design and the implant-abutment interface. PURPOSE: To compare the changes in soft and hard tissues when using a one-piece implant with a machined collar (TG) versus a two-piece implant with a progressive platform widening and a platform switching connection (SP). MATERIAL AND METHODS: Partially edentulous patients willing to receive one or two implants in the posterior maxilla or mandible were randomized to the control (TG) or to the test group (SP). Final prostheses were delivered after 12 months. Radiographic measurements of interproximal bone levels (primary outcome) were assessed at implant loading and 1-year postloading. Clinical, patient related outcomes and adverse events were assessed at loading and after 6 and 12 months. RESULTS: Sixty-one implants were placed in 47 patients, 37 patients (18 in the TG group and 19 in the SP group), and 47 implants (23 TG and 24 SP) completed the 24-months follow up. At the patient level, a significantly greater bone resorption from baseline to implant loading was observed in the SP group (-0.42 ± 0.45 vs -0.07 ± 0.45; P = .001*), while from loading to the final visit, the TG group had significantly greater bone loss than the SP group (-0.26 ± 0.22 vs -0.11 ± 0.2; P = .020*). At 24 months after surgery, there were no significant differences between both groups (control: 0.33 ± 0.49 vs test: 0.53 ± 0.53; P = .230). Similarly, no significant differences were observed for the secondary outcomes. CONCLUSIONS: Both types of implant reported high survival rates and similar bone level changes, clinical parameters, and patient related outcomes after 12 months of loading.

Clinical efficacy of subgingival debridement with adjunctive erbium:yttrium-aluminum-garnet laser treatment in patients with chronic periodontitis: a randomized clinical trial.

BACKGROUND: The efficacy of erbium:yttrium-aluminum-garnet (Er:YAG) laser application as an adjunct to subgingival debridement in the treatment of chronic periodontitis (CP) is controversial. This study assesses the efficacy of combining full-mouth subgingival debridement with Er:YAG laser application in the treatment of patients with CP. METHODS: In this 12-month, single-masked, parallel-group clinical trial, 40 patients with moderate CP were selected and randomly assigned to a test group (one session of full-mouth ultrasonic subgingival debridement followed 1 week later by Er:YAG application in sites with initial probing depths [PDs] of ≥4.5 mm) and a control group (two sessions of ultrasonic debridement within 1 week). The main outcome variable was change in PD; the secondary outcomes were change in clinical attachment level and proportion of sites with bleeding on probing. Outcomes were assessed at baseline and after 3, 6, and 12 months. Data were analyzed as intention to treat using analysis of variance to assess intergroup differences. RESULTS: Both treatments resulted in significant clinical improvements. The test group achieved, in comparison with the control, a significantly lower percentage of sites with PD ≥4.5 mm (17.44% versus 22.83%, respectively; P = 0.004) and a tendency for a lower percentage of sites with PD ≥4.5 mm and bleeding on probing (9.78% versus 12.69%; P = 0.052). CONCLUSION: This limited added clinical effect may justify the use of a protocol combining full-mouth ultrasonic debridement with laser therapy in the treatment of initial moderate CP.

A Prospective Noninterventional Study to Evaluate Survival and Success of Reduced Diameter Implants Made From Titanium-Zirconium Alloy.

Narrow diameter implants may be at increased risk of overload due to occlusal forces; therefore, implants with higher fatigue strength may be beneficial. The aim of this observational study was to evaluate survival and success of narrow diameter (Ø 3.3 mm) TiZr alloy (Roxolid, Institut Straumann AG, Basel, Switzerland) implants for 2 years in daily dental practice. This was a prospective, non-interventional, multicenter study; no specific patient inclusion or exclusion criteria were applied. Each patient received at least one TiZr implant; the treatment plan, including implant loading and final restoration, was at the investigator's discretion. The primary outcome was implant survival and success after 1 year. Secondary outcomes included 2-year survival and success and marginal bone level change. A total of 603 implants were placed in 357 patients. Cumulative survival and success rates were 97.8% and 97.6%, respectively, after 1 year and 97.6% and 97.4%, respectively, after 2 years. Bone levels remained stable in the majority of patients, and soft tissue remained stable up to 2 years. Within the limitations of a non-interventional study design, TiZr implants showed excellent survival and success with minimal bone loss up to 2 years in daily dental practice. The results compare favorably with those of small-diameter implants in controlled clinical trials.