Effectiveness of Autologous Platelet Concentrates in the Sinus Lift Surgery: Findings from Systematic Reviews and Meta-Analyses.

Maxillary sinus augmentation is one of the most predictable procedures for the rehabilitation of the posterior maxilla. The current overview aimed to summarize the findings provided by systematic reviews (SRs) and meta-analyses on the effectiveness of autologous platelet concentrates (APCs) in sinus lift and to assess the methodological quality of the included SRs. Three electronic databases have been explored. SRs and meta-analyses addressing the effectiveness of APCs in sinus lift technique were included. Clinical, radiographic and histomorphometric findings were considered for APCs as solely grafting materials and APCs in combination with biomaterials. Outcomes were implant survival rate (ISR), implant stability (IS), implant failure (IF), postoperative complications, histomorphometric findings, radiographic bone gain, bone volume and bone density. The methodological quality of the included SRs was assessed using the updated version of "A Measurement Tool to Assess Systematic Review" (AMSTAR-2). Thirty SRs were included. The methodological quality of the included reviews ranged from critically low (3 studies) to high (9 studies). The included SRs showed favorable clinical outcomes, short-term new bone formation and no biological complications when APCs were used both as solely graft material or in combination with other biomaterials. However, no significant additional effects in the long-term period were observed. APCs did not add any further positive effects compared to the physiological healing derived by the natural blood clot. The current overview of SRs highlighted the need for high-quality SRs evaluating the role of APCs in sinus lift though network meta-analyses, in order to identify the most powerful material for sinus lift augmentation. The use of APCs improves the healing of soft tissues and the postoperative quality of life in the short-term period. Thus, its application can be recommended.

The Effectiveness of Autologous Platelet Concentrates in the Clinical and Radiographic Healing after Endodontic Surgery: A Systematic Review.

Regenerative techniques are increasingly applied in endodontic surgery, but different materials may have varying impacts on soft and hard tissue healing. This systematic review aims to evaluate the effectiveness of autologous platelet concentrates (APCs) in clinical and radiographic healing after endodontic surgery. The data for this systematic review were processed following the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines for improving the reporting of systematic reviews and meta-analyses. A literature search was conducted until October 2023 on PubMed, Scopus, and Cochrane Databases. Randomized controlled trials and controlled clinical trials addressing the use of APCs in patients who presented persistent periapical lesions and needed periapical surgery were included. Dual publications, narrative reviews, systematic reviews, case series, questionnaires, animal studies, case reports, letters to the editor, in vitro studies, and abstracts were excluded. In total, the search resulted in 14 papers. Clinical and radiographical findings were reported, showing that when APCs were used, patients exhibited less pain and swelling and a greater reduction of apical radiolucency after 12 months follow-up on average. However, the moderate/high risk of bias of included studies and their high heterogeneity, do not allow one to draw definitive conclusions on the effectiveness of APC after endodontic surgery.

Stress distribution in resin-based CAD-CAM implant-supported crowns.

OBJECTIVE: This study aimed to evaluate the influence of new resin-based CAD-CAM implant-supported materials on posterior crown restoration stress and strain concentrations. METHODS: A previous 3D implant model was edited to receive a cement-retained posterior crown manufactured with different CAD/CAM materials (Estelite P Block, Estelite Block II or Estelite Layered Block). Each solid model was exported to the computer-aided engineering software and submitted to the finite element analysis of stress and strain. Material properties were assigned to each solid with isotropic and homogeneous behavior according to the manufacturer information. A vertical load of 600 N was applied in the occlusal region of the crown, via a simulated food bolus, and stress was calculated in Von Misses (σVM) for the implant, abutment and screw, Maximum (σMAX) Principal Stresses for the crown and microstrain for the bone. RESULTS: All simulated materials showed acceptable stresses levels with a similar stress pattern among the models. At the crown intaglio region and cement layer, however, differences were observed: Estelite P Block showed a lower tensile and shear stresses magnitude when compared to other resin-based materials with lower elastic modulus. SIGNIFICANCE: The stress effect of different resin-based CAD-CAM implant-supported crowns is predominant in the crown and cement layer, with Estelite P Block showing 7.4 % versus 9.3 % and 9.2 % for Estelite Block II and Estelite Layered Block of crown failure risk.

Mechanical Behavior of Alkasite Posterior Restorations in Comparison to Polymeric Materials: A 3D-FEA Study.

The present investigation evaluated the effect of the combination of different dental filling materials in Class I cavities under occlusal loading using three-dimensional finite elements analysis (FEA). Six computer-generated and restored models of a lower molar were created in the CAD software and compared according to the biomechanical response during chewing load condition. Two adhesively bonded bulk restorative materials [bulk-fill resin composite (BF) or Alkasite (Alk)] were evaluated with or without the presence of a base material below (flowable resin composite or glass ionomer cement). A food bolus was placed on the occlusal surface mimicking the compressive occlusal load (600 N) during the static linear analysis. The maximum principal stress (tensile) was calculated as stress criteria in enamel, dentin and restoration. All models showed high stresses along the enamel/restoration margin with a similar stress trend for models restored with the same upper-layer material. Stress values up to 12.04 MPa (Alk) or up to 11.12 MPa (BF) were recorded at the enamel margins. The use of flexible polymeric or ionic base material in combination with bulk-fill resin composite or Alk did not reduce the stress magnitude in dentine and enamel. Class I cavities adhesively restored with bulk-fill resin composite showed lighter stress concentration as well as Alk. Therefore, adhesively bonded Alk restoration showed a promising mechanical behavior when used with different base materials or as a bulk restoration for posterior Class I cavity.

Effect of Biologically Oriented Preparation Technique on the Stress Concentration of Endodontically Treated Upper Central Incisor Restored with Zirconia Crown: 3D-FEA.

The aim of this study was to evaluate the effect of biologically oriented preparation technique on the stress concentration of endodontically treated upper central incisors restored with zirconia crown (yttria-stabilized zirconia polycrystalline ceramic) through finite element analysis (FEA). Four models of maxillary central incisors containing enamel, dentin, periodontal ligament, cortical and medullary bone were created in CAD. Each model received a polymeric core-build up with nanofilled dental resin composite. The evaluated models were SM-preparation in shoulder 90°; CM-chamfer preparation; BOPT-biologically oriented preparation technique and BOPTB-BOPT preparation 1 mm below the cement-enamel junction. All models received zirconia crowns (5Y-TZP), fiberglass post and 1 mm ferrule. The models were imported into the analysis software with parameters for mechanical structural testing using the maximum principal stress and the tensile strength as the analysis criteria. Then, load of 150 N was applied at the cingulum with 45° slope to the long axis of the tooth, with the fixed base for each model. The type of marginal preparation affected the stresses concentration in endodontically treated teeth and in the zirconia crown margin. Considering the stress magnitude only, BOPT is a viable option for anterior monolithic zirconia crowns; however, with the highest stress magnitude at the restoration margin.

Lower third molar inclusion associated with paraesthesia: A case report.

When lower third molar inclusion is associated with neurosensorial complications, the treatment of choice is its surgical avulsion. One of these complications, that may be the most alarming during a first medical examination, is hemi-lip paraesthesia, that can appear in the presence of several mandibular lesions. This is a report of a rare clinical case in which paraesthesia was linked to the closeness between the root block of the dental element and the mandibular canal, which houses the neurovascular trunk of the lower mandibular nerve. A 64 year-old male Caucasian patient, presented with the chief complaint of past periodic inflammatory events in the retromolar region of the oral cavity and hemi-lip paraesthesia. Upon local clinical and radiological examination, a lower left third molar with class 3 position C inclusion was incriminated. The medical history of the patient revealed well compensated diabetes mellitus type II, and pharmacologically controlled hypertension. The tooth was surgically removed using piezoelectric instruments. Before and after surgery, three types of tests (tactile, pain and thermal sensitivity) were carried out to delimit the area affected by paraesthesia. At 7 days, the area of hypoesthesia of the hemi-lip was significantly reduced. Further improvement in tactile and thermal sensitivity occurred in subsequent follow-up, at 1 and 3 months, postoperatively. This clinical case demonstrates that the surgical intervention performed with piezoelectric instruments prevented the damage of an important structure such as the lower mandibular nerve, and promoted regression of a contingent paraesthesia.

Perceived Job Insecurity and Depressive Symptoms among Italian Dentists: The Moderating Role of Fear of COVID-19.

Containment measures adopted to reduce the spread of coronavirus disease 2019 (COVID-19) have produced a general perception of job insecurity. Dentists have been highly affected by such measures, as they represent an easy source of contagion. As perceived job insecurity is associated with psychological distress and Italian dentists have been highly affected by the COVID-19 outbreak in terms of potential financial loss and the risk of being infected, this study aimed at assessing whether the fear of COVID-19 moderated the effect of perceived job insecurity on depressive symptoms. This cross-sectional online study has included 735 Italian dentists recruited during the lockdown and ranging in age from 27 to 70 years old (495 men and 240 women). A quantile regression model with an inference based on the median and with an interaction term between the fear of COVID-19 and perceived job insecurity has been used to estimate the hypothesized associations. The results indicated that both perceived job insecurity and fear of COVID-19 were positively associated with depressive symptoms, and that the effect of perceived job insecurity on depressive symptoms was weaker among those with a low fear of COVID-19. The findings may inform public health policies for dentists in relation to reducing the risk of developing negative mental health outcomes.

Treatment of periodontal pockets at the distal aspect of mandibular second molar after surgical removal of impacted third molar and application of L-PRF: a split-mouth randomized clinical trial.

OBJECTIVES: Presence of clinical attachment loss on the distal aspect to the second molar may be associated with malposition of the third molar. The aim of this study was to evaluate the reduction of clinical attachment loss at the distal aspect of the second molar after third molar extraction and application of leukocyte- and platelet-rich fibrin (L-PRF). METHOD AND MATERIALS: Eighteen subjects with a clinical attachment loss on the distal site to the second molar associated with impacted third molar in both sides of the jaw were recruited for the study. For each subject the teeth were randomly allocated in test and control groups. After surgical removal of the impacted third molar, the L-PRF was inserted in the fresh alveolar socket of test sites; in the control sites no graft was inserted after extraction. Full-mouth plaque score, full-mouth bleeding score, clinical attachment level (CAL), probing depth, and gingival recession were assessed at baseline and 6 months later. RESULTS: After 6 months, mean CAL change was 1.99 ± 1.18 mm in the test group and 1.15 ± 1.01 mm in the control group; probing depth change was 1.33 ± 0.87 mm in the test group and 0.50 ± 0.63 mm in the control group. Statistically significant differences (P < .05) were observed between groups in terms of CAL and probing depth changes. No differences were found in gingival recession changes. CONCLUSION: Within the limits of the present study, the sites treated by means of application of L-PRF after impacted third molar extraction showed better results in terms of CAL gain and probing depth reduction when compared with control sites.

Pre-treatment Neutrophil-to-Lymphocyte Ratio as a predictor for occult cervical metastasis in early stage (T1-T2 cN0) squamous cell carcinoma of the oral tongue.

BACKGROUND: Optimum management of clinically negative neck (cN0) remains controversial in early stage (T1-T2) squamous cell cancer of the oral tongue (OTSCC). The purpose of this study was to investigate the value of pre-treatment Neutrophil-to lymphocyte ratio (NLR) in predicting occult cervical metastasis in stage I and II OTSCC. METHODS: We carried out a retrospective chart review on 110 patients suffering from early stage OTSCC who were surgically treated with tumour excision and elective neck dissection (END). Our cohort was divided in pN+ and pN0 groups basing on histopathological examination after elective neck dissection. For each patient pre-treatment NLR was calculated. RESULTS: A statistically significant relationship between high levels of pre-treatment NLR and probability rate for neck occult metastases (0.000496 p-value) has been found. On our model the cut-off value was set for NLR >2.93. Above this level the probability to finding metastasis in a clinically negative neck increases exponentially. CONCLUSION: These preliminary results offer clinicians an easily obtainable tool to stratify patients based on risks of metastatic node in whom END could be indicated.

Safe approach in "All-on-four" technique: a case report.

The "All-on-Four" concept is based on the placement of four implants in the anterior part of fully edentulous jaws to support a provisional, fixed, and immediately loaded full-arch prosthesis. Combining tilted and straight implants for supporting fixed prostheses can be considered a viable treatment modality resulting in a more simple and less time consuming procedure, in significantly less morbidity, in decreased financial costs and a more comfortable postsurgical period for the patients. The authors present a case report with mandibular atrophy and left mental foramina on the top of the residual crest.

Aesthetics in oral implantology: biological, clinical, surgical, and prosthetic aspects.

OBJECTIVES: The aim of this study was to identify a correct clinical, surgical, and prosthetic management of endosseous implants replacing missing teeth in the anterior maxilla, achieving predictable aesthetic outcomes. Placement of immediate post-extraction implants without incisions or flap elevation is one of the surgical treatment options able to improve the healing and regenerative potentials of the fresh socket. MATERIALS: Fifty-five patients (33 men, 22 women), ranging in age from 19 to 57 years (mean 29), were selected for this study. All the patients were not smokers, no bruxers, presented stable soft tissue conditions, an acceptable occlusion, and the absence of pathologies that would contraindicate bone healing. Patients were treated with implants made by 2 manufacturers: Institute Straumann, Walderburg, Switzerland and Friadent, Mannheim, Germany. A total of 87 implants were placed immediately after each failing tooth had been removed. The temporary restoration was placed 3 months after implant placement, and the final restoration was placed 4 months from the surgical procedure. The patients were evaluated clinically and radiographically at implant placement, and 2, 4, 18, and 24 months post-insertion. RESULTS: At 24 months, only 3 implants were lost (2 in male patients;1 in female patient). All of these failed implants did not achieve osseointegration. The overall success rate was 96.6%, with an implant failure rate of 3.4%, all prior to restoration. CONCLUSIONS: The immediate placement in the anterior maxilla fresh extraction sockets without incisions or flaps elevation is a surgical option that can ensure ideal peri-implant tissues healing, preserving the presurgical gingival and bone aspects. For a predictable aesthetic result, the most important aspect seems to be the height and thickness of the buccal bone wall, which remain after immediate placement of the fixture.

Use of autologous platelet-rich plasma (PRP) in periodontal defect treatment after extraction of impacted mandibular third molars.

PURPOSE: The extraction of mesioangular impacted third molars may cause multiple periodontal defects at the distal root of the second molar. Platelet-rich plasma (PRP) is a material containing many autologous growth factors that may be used in repairing and preventing periodontal complications at the distal root of the second molar adjacent to the extracted third molar. PATIENTS AND METHODS: We analyzed the effects of autologous PRP on periodontal tissues after extraction of the third molar in 18 young patients (age, 21-26 years). Inclusion criteria were the presence of a pocket distal to the mandibular second molar with a probing depth>or=7.5 mm and a probing attachment level>or=6 mm. RESULTS: We observed, at 12 weeks after surgery, a notable reduction in the probing depth and an improvement in the probing attachment level in those cases treated with PRP compared with the controls, as well as formation of new bone tissue in the bone defect. CONCLUSION: We showed that PRP is effective in inducing and accelerating bone regeneration for the treatment of periodontal defects at the distal root of the mandibular second molar after surgical extraction of a mesioangular, deeply impacted mandibular third molar.

Stereolithography in oral implantology: a comparison of surgical guides.

This article presents the use of stereolithography in oral implantology. Stereolithography is a new technology that can produce physical models by selectively solidifying an ultraviolet-sensitive liquid resin using a laser beam, reproducing the true maxillary and mandibular anatomic dimensions. With these models, it is possible to fabricate surgical guides that can place the implants in vivo in the same places and same directions as those in the planned computer simulation. A 70-year-old woman, in good health, with severe mandibular bone atrophy was rehabilitated with an over-denture supported by 2 Branemark implants. Two different surgical planning methods were considered: 1) the construction of a surgical guide evaluating clinical aspects, and 2) the surgical guide produced by stereolithographic study. The accuracy of surgical planning can reduce the problems related to bone density and dimensions. Furthermore, the stereolithographic study assured the clinicians of a superior location of fixtures in bone. Surgical planning based on stereolithographic technique is a safe procedure and has many advantages. This technologic advance has biologic and therapeutic benefits because it simplifies anatomic surgical management for improved implant placement.