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

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

Enamel matrix derivative as adjunctive to non-surgical periodontal therapy: a systematic review and meta-analysis of randomized controlled trials.

OBJECTIVES To assess the potential additional benefit of the local application of enamel matrix derivative (EMD) on the clinical outcomes following non-surgical periodontal therapy (NSPT) (steps 1 and 2 periodontal therapy). MATERIALS AND METHODS A systematic literature search was performed in several electronic databases, including Medline/PubMed, Embase, The Cochrane Register of Central Trials (CENTRAL), LILACS, and grey literature. Only randomized controlled clinical trials (RCTs) were eligible for inclusion. Clinical attachment level (CAL) change (primary outcome), probing pocket depth (PPD), and bleeding on probing (BoP) reductions (secondary outcomes) were evaluated. The Cochrane Risk of Bias tool (RoB 2.0) was used to assess the quality of the included trials. Weighted mean differences (WMDs) and 95% confidence intervals (CIs) between test and control sites were estimated using a random-effect model for amount of mean CAL and PPD change. RESULTS Six RCTs were included for the qualitative analysis, while data from 4 studies were used for meta-analysis. Overall analysis of CAL gain (3 studies) and PPD reduction (4 studies) presented WMD of 0.14 mm (p = 0.74; CI 95% - 0.66; 0.94) and 0.46 mm (p = 0.25; CI 95% - 0.33; 1.26) in favor of NSPT + EMD compared to NSPT alone respectively. Statistical heterogeneity was found to be high in both cases (I2 = 79% and 87%, respectively). CONCLUSIONS Within their limitations, the present data indicate that the local application of EMD does not lead to additional clinical benefits after 3 to 12 months when used as an adjunctive to NSPT. However, due to the high heterogeneity among the studies, additional well-designed RCTs are needed to provide further evidence on this clinical indication for the use of EMD. CLINICAL RELEVANCE The adjunctive use of EMD to NSPT does not seem to additionally improve the clinical outcomes obtained with NSPT alone

Addition of Synthetic Biomaterials to Deproteinized Bovine Bone Mineral (DBBM) for Bone Augmentation-A Preclinical In Vivo Study.

(1) Aim: To investigate the effect of synthetic bone substitutes, α-tricalcium phosphate (α-TCP) or bi-layered biphasic calcium-phosphate (BBCP) combined with deproteinized bovine bone mineral (DBBM), on bone formation. (2) Methods: Thirty critical size defects were randomly treated with the following five different treatment modalities: (1) negative control (NC, empty), (2) DBBM, (3) α-TCP + DBBM (1:1), (4) BBCP 3%HA/97%α-TCP + DBBM (1:1), and (5) BBCP 6%HA/94%α-TCP + DBBM (1:1). The samples, at four weeks post-surgery, were investigated by micro-CT and histological analysis. (3) Results: A similar level of new bone formation was demonstrated in the DBBM with α-TCP bone substitute groups when compared to the negative control by histomorphometry. DBBM alone showed significantly lower new bone area than the negative control (p = 0.0252). In contrast to DBBM, the micro-CT analysis revealed resorption of the α-TCP + DBBM, BBCP 3%HA/97%α-TCP + DBBM and BBCP 6%HA/94%α-TCP + DBBM, as evidenced by a decrease of material density (p = 0.0083, p = 0.0050 and p = 0.0191, respectively), without changing their volume. (4) Conclusions: New bone formation was evident in all defects augmented with biomaterials, proving the osteoconductive properties of the tested material combinations. There was little impact of the HA coating degree on α-TCP in bone augmentation potential and material resorption for four weeks when mixed with DBBM

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

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

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

ObjectivesTo histologically evaluate the effects of a novel human recombinant amelogenin (rAmelX) on periodontal wound healing / regeneration in recession-type defects.Materials and methodsA 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.ResultsThe 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 & PLUSMN; 0.36 mm vs. 3.48 mm & PLUSMN; 1.13 mm). Bone formation measured 2.15 mm & PLUSMN; 0.8 mm in the test group and 2.24 mm & PLUSMN; 1.23 mm in the control group, respectively, without a statistically significant difference (p = 0.94).ConclusionsThe 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

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