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.

Reducing errors in guided implant surgery to optimize treatment outcomes.

Clinical considerations and treatment criteria in implant placement are constantly evolving. Prosthetically driven implant surgery has become the standard of care to improve short and long-term functional and esthetic outcomes. Therefore, implant position and angulation are planned according to the available bone, anatomical structures, and the requirements of the future prosthetic superstructure. In parallel with these developments, significant progress has been made in data imaging and different software technologies to allow the integration of data within a digital file format. Digitalization in implant surgery enables optimal planning of implant position, as well as the ability to transfer this planning to the surgical field-a process defined as "computer-supported implant planning and guided surgery." The aims of the present review are as follows: (a) to critically appraise the indications and potential "added value" of guided implant surgery, elaborating the main differences between dynamic and static guidance; and (b) to discuss the most important clinical considerations relevant for the different steps of the workflow that might influence the surgical outcome and to offer recommendations on how to avoid or reduce process errors in order to optimize treatment outcomes.

Soft tissue-related complications and management around dental implants.

Implant installation for replacing missing teeth is a frequent treatment procedure with high long-term survival and success rates. However, the success of implant therapy may be jeopardized by several complications related to mistakes in treatment planning, surgical procedure, management of hard and soft tissues, and infections. Increasing evidence suggests that the stability of the soft tissues surrounding osseointegrated dental implants may substantially influence long-term clinical stability and esthetics. Therefore, when implant therapy is planned, the clinician must not only be able to perform the appropriate steps to maintain/create a stable soft tissue, but also needs to be aware of the potential sources for complications and possess the adequate knowledge for their appropriate management. The present paper provides an overview of the most important aspects related to the prevention and management of soft tissue-related complications in conjunction with implant therapy. The current literature indicates that the presence of an adequate width of keratinized attached mucosa around dental implants may lead to better soft and hard tissue stability, less plaque accumulation, limited soft tissue recession, and lower incidence of peri-implant mucositis. Proper implant positioning by carefully considering appropriate mesio-distal and bucco-lingual dimensions and implant angulation may prevent the loss of interdental soft tissues and development of soft tissue recessions. To optimize the width of keratinized attached mucosa, the appropriate soft tissue augmentation protocol should be selected for each particular indication. When the use of autogenous soft tissue grafts is planned, a thorough knowledge of the anatomical structures is mandatory in order to harvest soft tissue grafts of an appropriate quality and quantity and to avoid/minimize postoperative complications. Finally, the clinician needs to master the necessary steps in order to manage complications related to extensive bleeding and tissue necrosis that may occur in conjunction with soft tissue augmentation procedures.

Survival Rates of Amalgam and Composite Resin Restorations from Big Data Real-Life Databases in the Era of Restricted Dental Mercury Use.

Tooth decay, also known as caries, is a significant medical problem that harms teeth. Treatment is based on the removal of the carious material and then filling the cavity left in the tooth, most commonly with amalgam or composite resin. The consequences of filling failure include repeating the filling or performing another treatment such as a root canal or extraction. Dental amalgam contains mercury, and there is a global effort to reduce its use. However, no consensus has been reached regarding whether amalgam or composite resin materials are more durable, and which is the best restorative material, when using randomized clinical trials. To determine which material is superior, we performed a retrospective cohort study using a large database where the members of 58 dental clinics with 440 dental units were treated. The number of failures of the amalgam compared to composite resin restorations between 2014 and 2021 were compared. Our data included information from over 650,000 patients. Between 2014-2021, 260,905 patients were treated. In total, 19,692 out of the first 113,281 amalgam restorations failed (17.49%), whereas significantly fewer composite restorations failed (11.98%) with 65,943 out of 555,671. This study indicates that composite is superior to amalgam and therefore it is reasonable to cease using mercury-containing amalgam.

Biofilm formation, its removal, and consequent effect on the osteoblast response to titanium surfaces: A model for re-osseointegration.

BACKGROUND: The aim of the study was to characterize pathogenic biofilm formation on titanium surfaces, the ability to remove the biofilm and the osteoblast response to infected and cleaned titanium surfaces as a model for re-osseointegration. METHODS: Multispecies biofilm composed of Pseudomonas. gingivalis, F. nucleatum, S. sanguis, and A. naeslundii were grown on smooth, acid-etched, and acid-etched-aluminum-sprayed titanium surfaces. Bacterial viability was determined with live/dead staining. The biofilm was removed mechanically or together with adjunctive antibiotics. The osteoblast (Saos2) response to previously infected, treated and non-infected titanium surfaces were measured according to 4'-6-diamidino-2-phenylindole staining. Alkaline phosphatase levels and receptor activator of nuclear factor kappa-Β ligand/osteoprotegerin expression were measured with enzyme-linked immunosorbent assay and immunofluorescence staining, respectively The inflammatory environment was established by using differentiated HL-60 cells (neutrophils) pre-inoculated onto the biofilm clusters that were more prominent and less scattered on infected titanium surfaces before osteoblast attachment. RESULTS: Biofilm formed on all the tested surfaces, with an increased thickness on rough surfaces and no differences in bacterial viability. All the treatments reduced the amount of biofilm, but none led to bacteria-free surfaces. The treated surfaces showed reduced osteoblast attachment and reduced alkaline phosphatase activity compared with non-infected surfaces. Additionally, treated surfaces showed an osteoblast shift to a pro-osteoclastic-induction phenotype, compared with non-infected surfaces. The presence of experimental inflammation before osteoblast attachment reduced the levels of osteoblast attachment compared with that of the non-inflamed control. CONCLUSIONS: Biofilm removal from titanium surfaces is incomplete when hand instruments are used alone or in combination with antibiotics. The treated surfaces showed impaired osteoblast attachment and function, particularly in the presence of inflammation, which may prevent or decrease the ability for re-osseointegration.

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.

Soft tissue-related complications around anterior implants: commentary and clinical checklist.

Implant-based rehabilitation is a clinical challenge, especially in the esthetic area. Numerous factors influence the outcome of the rehabilitation; however, the two main factors are the bone and soft-tissue deficiencies at the intended implant site. Peri-implant soft tissue complications can arise from a combination of factors that can be summarized as two categories: diagnostic errors and surgical planning management errors. Most of the complications can be corrected after each step of the treatment and even after the delivery of the prosthetic restoration with adequate soft tissue management in order to give the patient an esthetically pleasing outcome. The aims of this article were: to present the current literature, to propose a clinical checklist to guide clinicians in evaluating the prognosis of the treatment utilizing soft tissue grafting, and to illustrate a case series partially employing the proposed clinical checklist. The proposed checklist could be helpful in evaluating the prognosis of the treatment utilizing only soft tissue grafting. In clinical cases in which the prognosis is classified as good, soft tissue management could be a viable treatment option before attempting more radical procedures like implant removal.

Diagnostic reproducibility of the 2018 Classification of Gingival Recession Defects and Gingival Phenotype: A multicenter inter- and intra-examiner agreement study.

BACKGROUND: The aim of this study was to investigate the inter- and intra-examiner agreement among international experts on the diagnosis of gingival recession defects using the 2018 Classification of Gingival Recession Defects and Gingival Phenotype as proposed in the 2017 World Workshop. METHODS: Standardized intraoral photographs from 28 gingival recession defects were evaluated twice by 16 expert periodontists. Recession type (RT), recession depth (RD), keratinized tissue width (KTW), gingival thickness (GT), detectability of the cemento-enamel junction (CEJ), and presence of root steps (RS) were recorded and used for the analysis. Intra- and inter-examiner agreements were calculated for individual variables and for the overall classification. Intraclass correlation coefficient with 95% CI was used for RD and KTW; Kappa with 95% CI was used for GT, CEJ, and RS; quadratic weighted Kappa with 95% CI was used for RT. RESULTS: Overall intra- and inter-examiner agreements were highest for KTW (0.95 and 0.90), lowest for GT (0.75 and 0.41), with the other variables in between (RD: 0.93 and 0.68, RS: 0.87 and 0.65, RT: 0.79 and 0.64, CEJ: 0.75 and 0.57). Overall intra- and inter-examiner agreements for the matrix were 62% and 28%, respectively. Significant effects existed between one variable's measurement and other variables' agreements. CONCLUSIONS: The 2018 Classification of Gingival Recession Defects and Gingival Phenotype is clinically reproducible within the examiners, and when the variables forming the matrix are analyzed individually. The between-examiner agreement for the complete matrix showed lower reproducibility. The agreement was highest for KTW and RD, and least for GT.

Flapless Decoronation: A Minimally Invasive Approach.

Traumatic injuries to the permanent dentition are most common in children. In severe dentoalveolar injuries, especially avulsion and intrusion, dentoalveolar ankylosis is a common complication, leading to adverse effects on the developing alveolar bone and interfering with the eruption of the adjacent teeth. The decoronation procedure was suggested in 1984 to reduce these side effects related to ankylosis. The objective of the current publication is to describe a minimally invasive, flapless decoronation procedure aimed to minimize and simplify the surgical procedure of decoronation, and ease its clinical acceptance, particularly in young children. The technique is described in a detailed protocol and demonstrated in two cases. Under local anesthesia, the dental crown is removed, and the root is reduced by 1.5-2.0 mm apically to the marginal bone crest. The root canal content is then removed, allowing it to fill with blood. The socket is coronally sealed with a porcine-derived collagen matrix (PDCM) sutured using the "parachute" technique over the resected root, allowing close adaptation to the surrounding soft tissue. In conclusion, the presented technique of flapless decoronation is a modification of the classic decoronation procedure, which can be used as a minimally invasive technique to simplify the surgical procedure and the post-operative process.

Sinus floor augmentation using large (1-2 mm) or small (0.25-1 mm) bovine bone mineral particles: a prospective, intra-individual controlled clinical, micro-computerized tomography and histomorphometric study.

OBJECTIVES: To compare the amount of newly formed bone after sinus floor augmentation with two different particle sizes of bovine bone mineral (BBM) using clinical, micro-computerized tomography (CT) and histological techniques. METHODS: Bilateral sinus floor augmentations were performed in 10 patients. Six to 9 months later, bone samples were retrieved and analyzed. RESULTS: Results: Both groups were not different in vertical bone height achieved after augmentation, post-operative complications and maximal torque for the insertion of implants. Micro-CT measurements could not detect a statistically significant difference in bone volume between the groups (with a tendency for new more bone in the small granules group). Histomorphometric analysis revealed that both granule sizes produced the same pattern of bone formation, surrounding the graft granules, and producing a shape of a network, "bridging" between the BBM particles. Multi-nucleated giant cells, probably osteoclasts, were observed directly on the BBM particle surface in both groups. The osteoclast-like cells preferred the small-size BBM particles and not the large particles both in the small-size and the large-size granules group. CONCLUSION: Both sizes of BBM granules preformed equally and achieved the aim of the sinus floor augmentation procedure clinically and histologically.

A Novel Surgical Approach to Modify the Periodontal Phenotype for the Prevention of Mucogingival Complications Related to Orthodontic Treatment.

Certain bone morphologies and soft tissue thickness (ie, phenotype) are considered to be risk factors for the development of gingival recessions following orthodontic tooth movement. Preoperative evaluation of the periodontal phenotype, in the frame of orthodontic treatment plan, identify teeth at high risk for mucogingival complications related to orthodontic therapy. The new surgical technique is illustrated in a clinical case. A patient with a thin phenotype without visible gingival recession had bone dehiscences in the anterior mandible. Prior to orthodontic treatment, simultaneous bone and soft tissue augmentation was performed using the combination of a highly cross-linked ribose porcine type I collagen membrane and a subepithelial palatal connective tissue graft. Two years after augmentation surgery and initiation of orthodontic treatment, a thick buccal tissue with a wide band of attached gingiva was observed without any clinical signs of root prominences, indicating a substantial change in periodontal phenotype. The clinical findings were corroborated by the 3D analysis, demonstrating substantial bone apposition on the buccal aspect of all roots in the treated area. The described surgical technique offers a valuable approach for regenerating hard and soft tissues in deficient areas prior to orthodontic therapy, thus preventing the development of gingival recessions.

Guided Implant Placement in Fully Edentulous Patients. The Full Retraction Protocol: Registration Technique to Improve Treatment Outcome.

Preoperative planning and implant placement can be optimized using implant planning software followed by the creation of an individual surgical guide. Alongside clinical advantages of using guided surgery, a variability in the accuracy of implant position has been reported. This variability is even more substantial in fully edentulous patients and attributed to errors from intrinsic and extrinsic sources. The aim of this paper is to discuss the potential process errors and present two digital data registration protocols to be implemented in fully edentulous patients. The suggested protocols are aimed to improve accuracy of data acquisition, data superimposition on planning software, and therefore treatment outcome as well.

Oral Care and Quality Evaluation: A Multicentric Study on Periodontal Treatment.

PURPOSE: No information is available on the perception of the quality of care in patients treated for periodontitis. The purpose of this article was to assess how periodontitis-affected patients perceive the quality of periodontal treatment (PT) and to measure the factors which may influence it. MATERIALS AND METHODS: 306 subjects who completed PT were invited to participate. Questionnaires and visual analogic scales (VAS) evaluating perception of quality of care, symptoms, and oral health related quality of life (OHRQoL) were handed out. Oral and periodontal indicators were collected before and after treatment. The impact of different factors on perception of quality was assessed with a regression model. RESULTS: Quality evaluation was high yet unrelated for both patients and clinicians (p = 0.983). Quality was negatively influenced by the number of residual oral infections (p < 0.001), patient's age (p = 0.07) and presence of residual pain at completion of PT (p = 0.02). Professionalism, kindness of the staff and communication skills were the characteristics mostly appreciated. The OHRQoL was influenced by the number of residual teeth (p < 0.001), increasing age of patients (p = 0.08), number of residual infections (p < 0.01) and pain (p = 0.04). CONCLUSIONS: Patients' quality perception appeared to be influenced by clinical and emotional aspects. Oral care providers should be aware of the impact of non-clinical factors in patients' appreciation of quality of treatment.

Effect of Subgingival Mechanical Debridement and Local Delivery of Chlorhexidine Gluconate Chip or Minocycline Hydrochloride Microspheres in Patients Enrolled in Supportive Periodontal Therapy: a Retrospective Analysis.

PURPOSE: To retrospectively evaluate the clinical outcomes of subgingival debridement (e.g. scaling and root planing, SRP) and application of either a chlorhexidine chip (PerioChip, PC) or Arestin (AR) minocycline microspheres in patients with chronic periodontitis during supportive periodontal treatment (SPT). MATERIALS AND METHODS: Patients diagnosed with moderate to severe chronic periodontitis who were treated with SRP and a slow-release device during SPT were evaluated (total n = 53; n = 37 received PC, n = 16 received AR). Clinical measurements at baseline, 3, 6 and 12 months included changes in probing pocket depth (PD), bleeding on probing (BOP) and clinical attachment level (CAL). RESULTS: Both treatments led to a reduction in PD and gain of CAL. AR showed higher improvements in pockets of ≥7 mm compared with PC. In contrast, PC was more effective in 5-6 mm PD. At one year following treatment, both treatments reduced the need-for-surgery index (95% to 100%) of the sites at baseline to 30% for AR and 42% for PC, with no differences between PC and AR. CONCLUSIONS: In patients enrolled in SPT, the use of both PC and AR in conjunction with subgingival mechanical debridement represents an effective treatment modality for improving the clinical outcomes and reducing the need for surgery.

A critically severe gingival bleeding following non-surgical periodontal treatment in patients medicated with anti-platelet.

BACKGROUND: Only a few dental procedures have been reported to cause life-threatening bleeding. All of these cases followed surgical intervention. MATERIAL AND METHODS: In this paper, we report a case of severe bleeding following non-surgical periodontal procedures in a patient treated with a dual anti-platelet regimen post-coronary stent insertion. RESULTS: Her medical history included ischaemic heart disease, hypertension and diabetes mellitus. Haemostasis was achieved at the conclusion of the non-surgical periodontal treatment. However, several hours later, the patient arrived at the emergency room and was diagnosed with hypovolemic shock. CONCLUSION: This case should raise the clinician's awareness of bleeding complications in non-surgical procedures as well as the risk for bleeding when a dual anti-platelet regimen is administered. The importance of patient monitoring and the use of local haemostatic agents is demonstrated in these cases.

Dental treatment in the era of new anti-thrombotic agents.

BACKGROUND: In recent years, there have been dramatic changes in anti-thrombotic treatment as a result of new anti-thrombotic agents, as well as changes in the indications for their use. As a consequence, dentists are encountering larger numbers of patients who are undergoing anti-thrombotic treatment and who have increased risk for bleeding. The current paper aims to review the literature regarding up-to-date anti-thrombotic treatment and provide information regarding their implications on dentistry. METHODS: An online search was performed of the literature published between 2000 and 2016. Articles dealing with evidence-based clinical guidelines for anti-thrombotic treatments, as well as literature reporting the use of anti-thrombotic medications were included. The manuscripts were screened according to their relevance to dentistry as well as their treatment protocol guidelines. RESULTS: In total, 5,539 publications were identified: 56 of 554 evidence-based clinical guidelines were found that dealt with treatment protocols with anti-thrombotic agents; and 132 of 5,539 articles describe direct anti-thrombotic medications. CLINICAL IMPLICATIONS: Dental treatment includes a risk for bleeding. As a result of the increasing number of patients taking new-generation anti-thrombotic drugs, dentists must be up to date regarding the implications of such drugs on dental treatment as well as the practical means to achieve haemostasis.

Alveolar Bone Morphology Following Periodontally Accelerated Osteogenic Orthodontics: A Clinical and Radiographic Analysis.

The aim of this study was to analyze alveolar bone morphology following periodontally accelerated osteogenic orthodontics. Treated patients were called for a full periodontal examination and a cone beam computed tomography scan. Mean treatment time was 6.08 months. Mean probing pocket depth was 2.7 mm. No gingival recessions were noted. In the maxilla, buccal plate thickness was 0.48 to 2.14 mm. In the mandible, bone thickness was 0.2 to 1.82 mm. Root fenestrations and dehiscences were present in up to 40% of the anterior teeth. Although clinical outcomes were favorable, due to the presence of multiple posttreatment bone fenestrations and dehiscences, a revision of the treatment protocol might be considered.

The Impact of Implant Design, Defect Size, and Type of Superstructure on the Accessibility of Nonsurgical and Surgical Approaches for the Treatment of Peri-implantitis.

PURPOSE: The success of nonsurgical or surgical treatments of peri-implantitis is unpredictable, often without a clear reason. The aim of this study was to investigate the efficacy of nonsurgical and surgical cleaning, focusing on the impact of implant design, defect size, type of superstructure, and experience of the operator. MATERIALS AND METHODS: Conical and straight implants were coated with a biofilm-like material and placed in shallow/deep defects in an artificial jaw model. Treatment was done by three operators and included either healing abutments or crowns as superstructures. Analysis was done using stereomicroscopy and ImageJ software. RESULTS: Nonsurgical treatment of peri-implantitis defects was inefficient in removing all biofilm areas, regardless of the depth of the defect. The type of implant, experience of the operator, or type of superstructure did not have a significant impact. Surgical treatment was more efficient than a nonsurgical approach with regard to biofilm residues. However, the surgical approach failed to clean the apical portion of the exposed part of the implants. CONCLUSION: Nonsurgical and surgical treatment were found to be ineffective in cleaning the exposed portion of implants with peri-implantitis. Treatment of peri-implantitis should therefore also include other approaches, such as chemical or biological modalities.