Digital planning and bone regenerative technologies: A narrative review.

OBJECTIVES: The aim of this narrative review was to explore the application of digital technologies (DT) for the simplification and improvement of bone augmentation procedures in advanced implant dentistry. MATERIAL AND METHODS: A search on electronic databases was performed to identify systematic reviews, meta-analyses, randomized and non-randomized controlled trials, prospective/retrospective case series, and case reports related to the application of DT in advanced implant dentistry. RESULTS: Seventy-nine articles were included. Potential fields of application of DT are the following: 1) the use of intra-oral scanners for the definition of soft tissue profile and the residual dentition; 2) the use of dental lab CAD (computer-aided design) software to create a digital wax-up replicating the ideal ridge and tooth morphology; 3) the matching of STL (Standard Triangulation Language) files with DICOM (DIgital COmmunication in Medicine) files from CBCTs with a dedicated software; 4) the production of stereolithographic 3D models reproducing the jaws and the bone defects; 5) the creation of surgical templates to guide implant placement and augmentation procedures; 6) the production of customized meshes for bone regeneration; and 7) the use of static or dynamic computer-aided implant placement. CONCLUSIONS: Results from this narrative review seem to demonstrate that the use of a partially or fully digital workflow can be successfully used also in advanced implant dentistry. However, the number of studies (in particular RCTs) focused on the use of a fully digital workflow in advanced implant dentistry is still limited and more studies are needed to properly evaluate the potentials of DT.

Indications for implant-supported rehabilitation of the posterior atrophic maxilla: A multidisciplinary consensus among experts in the field utilising the modified Delphi method.

PURPOSE: To establish consensus-driven guidelines that could support the clinical decision-making process for implant-supported rehabilitation of the posterior atrophic maxilla and ultimately improve long-term treatment outcomes and patient satisfaction. MATERIALS AND METHODS: A total of 33 participants were enrolled (18 active members of the Italian Academy of Osseointegration and 15 international experts). Based on the available evidence, the development group discussed and proposed an initial list of 20 statements, which were later evalu-ated by all participants. After the forms were completed, the responses were sent for blinded ana-lysis. In most cases, when a consensus was not reached, the statements were rephrased and sent to the participants for another round of evaluation. Three rounds were planned. RESULTS: After the first round of voting, participants came close to reaching a consensus on six statements, but no consensus was achieved for the other fourteen. Following this, nineteen statements were rephrased and sent to participants again for the second round of voting, after which a consensus was reached for six statements and almost reached for three statements, but no consensus was achieved for the other ten. All 13 statements upon which no consensus was reached were rephrased and included in the third round. After this round, a consensus was achieved for an additional nine statements and almost achieved for three statements, but no consensus was reached for the remaining statement. CONCLUSION: This Delphi consensus highlights the importance of accurate preoperative planning, taking into consideration the maxillomandibular relationship to meet the functional and aesthetic requirements of the final restoration. Emphasis is placed on the role played by the sinus bony walls and floor in providing essential elements for bone formation, and on evaluation of bucco-palatal sinus width for choosing between lateral and transcrestal sinus floor elevation. Tilted and trans-sinus implants are considered viable options, whereas caution is advised when placing pterygoid implants. Zygomatic implants are seen as a potential option in specific cases, such as for completely edentulous elderly or oncological patients, for whom conventional alternatives are unsuitable.

Patient-reported outcome measures of leucocyte- and platelet-rich fibrin (L-PRF) or hemostatic agent application at palatal donor sites after free gingival graft harvesting: a randomized controlled clinical trial.

OBJECTIVE: The aim of this study was to evaluate the patient's morbidity and postsurgical complications after treatment of palatal donor sites after free gingival graft harvesting using leucocyte- and platelet-rich fibrin (L-PRF) membranes or a hemostatic agent with oxidized and regenerated cellulose. METHOD AND MATERIALS: Forty-two palatal donor sites after free gingival graft harvesting in 42 patients were randomly assigned to experimental (L-PRF membrane) or control procedure (hemostatic agent). The primary outcome was postoperative pain related to the wound located at the palatal area, and the secondary outcomes were postoperative discomfort, inability to chew, postoperative stress, surgical chair time, thickness of the palatal fibromucosa, and thickness of the free gingival graft. The patient-reported outcome measures were recorded after 1 week. RESULTS: After 1 week, a statistically significant difference was found between groups in terms of postoperative stress (P = .008). No statistically significant differences in terms of postoperative pain (P = .326), patient discomfort (P = .509), inability to chew (P = .936), or surgical chair time (P = .932) were recorded between the test and the control group. No statistically significant differences were recorded in terms of thickness of the palatal fibromucosa (P = .647) and thickness of the free gingival graft (P = .756) between groups. Postsurgical wound healing complications (ie, necrosis or infections) were not observed in both groups. CONCLUSION: Within their limitations, the present outcomes indicated that the application of L-PRF membrane at palatal donor sites after FGG harvesting did not produce significant advantages for the patients.

Minimal invasiveness in vertical ridge augmentation.

Vertical ridge augmentation is one of the most challenging procedures in implant dentistry because of the advanced skills required by the operator and the fact that bone augmentation is aimed outside the bony contour, in an environment of reduced blood supply. What is more, the flap management required to ensure soft tissue closure frequently leads to associated comorbidities in terms of swelling and hematomas. For these reasons, and even if autologous onlay block grafts are still the gold standard, new techniques and biomaterials have favored the development of potentially less invasive approaches. The present work evaluates the most recent strategies in vertical ridge augmentation to reduce invasiveness and complications, including diagnostic/treatment planning considerations, surgical techniques, digital tools (eg, customized titanium meshes/membranes or bone blocks), and future trends in the field of tissue engineering and cell therapy.

Radiographic protrusion of dental implants in the maxillary sinus and nasal fossae: A multidisciplinary consensus utilising the modified Delphi method.

The aim of the present study was to generate an international and multidisciplinary consensus on the clinical management of implant protrusion into the maxillary sinuses and nasal fossae. A total of 31 experts participated, 23 of whom were experts in implantology (periodontologists, maxillofacial surgeons and implantologists), 6 were otolaryngologists and 2 were radiologists. All the participants were informed of the current scientific knowledge on the topic based on a systematic search of the literature. A list of statements was created and divided into three surveys: one for all participants, one for implant providers and radiologists and one for otolaryngologists and radiologists. A consensus was reached on 15 out of 17 statements. According to the participants, osseointegrated implants protruding radiographically into the maxillary sinus or nasal fossae require as much monitoring and maintenance as implants fully covered by bone. In the event of symptoms of sinusitis, collaboration between implant providers and otolaryngologists is required. Implant removal should be considered only after pharmacological and surgical management of sinusitis have failed.

Histological assessment of mandibular bone tissue after guided bone regeneration with customized computer-aided design/computer-assisted manufacture titanium mesh in humans: A cohort study.

BACKGROUND: Innovative customized computer-aided design/computer-assisted manufacture (CAD-CAM) titanium meshes have been proposed for guided alveolar bone regeneration. Histological confirmation on the quality of the regenerated bone is needed. Purpose of the study is to assess the integration capabilities of these innovative meshes and to evaluate the histological features of the regenerated alveolar bone. MATERIALS AND METHODS: Twenty partially edentulous patients, with severe posterior mandibular atrophy, underwent a guided bone regeneration technique by means of customized CAD-CAM titanium mesh in association with a mixture of autologous bone in chips and deproteinized bovine bone (1:1). At 9 months of healing, titanium meshes and bone samples were collected and histomorphometrically analyzed. RESULTS: In all patients, implants were placed according to the original plan. At histologic analysis, mesh appeared well osseointegrated, except that in sites where membrane exposure occurred. In all sites, newly formed tissue resulted highly mineralized, well-organized, and formed by 35.88% of new lamellar bone, 16.42% of woven bone, 10.88% of osteoid matrix, 14.10% of grafted remnants, and 22.72% of medullary spaces. Blood vessels were the 4% of the tissue. CONCLUSIONS: Data from this study support the use of customized CAD/CAM titanium mesh for regeneration of vital, well-structured, and vascularized alveolar bone.

Wound Closure and Simultaneous Soft Tissue Augmentation at Fresh Extraction Sockets: A Simplified Technique Adopting a Xenogeneic Collagen Matrix.

A simplified surgical technique is presented for closure and soft tissue augmentation of fresh extraction sockets that utilizes a xenogeneic collagen matrix as a substitute for a combined onlay-interpositional connective tissue graft. Ten alveoli receiving a socket preservation procedure (n = 5) or an immediate submerged implant (n = 5) were sealed with a xenogeneic collagen matrix, stabilized under small palatal and buccal full-thickness envelope flaps. Eight weeks after surgery, full wound closure was achieved in 9 out of 10 sites with satisfactory esthetic integration (mean ΔE score: 3.76). Results from this descriptive observational study suggest that this technique may represent a valuable and minimally invasive solution to simplify closure and soft tissue augmentation of fresh extraction sockets.

Diagnosing odontogenic sinusitis: An international multidisciplinary consensus statement.

BACKGROUND: Odontogenic sinusitis (ODS) is distinct from non-odontogenic rhinosinusitis, and often requires multidisciplinary collaboration between otolaryngologists and dental providers to make the diagnosis. The purpose of this study was to develop international multidisciplinary consensus on diagnosing ODS. METHODS: A modified Delphi method was used to assess for expert consensus on diagnosing bacterial ODS. A multidisciplinary panel of 17 authors with ODS expertise from 8 countries (8 otolaryngologists, 9 dental specialists) was assembled. Each author completed 2 of 3 surveys (2 specialty-specific, and 1 for all authors). Thirty-seven clinical statements were created, focusing on 4 important diagnostic components: suspecting ODS; confirming sinusitis in ODS; confirming different dental pathologies causing ODS; and multidisciplinary collaborative aspects of diagnosing ODS. Target audiences were all otolaryngologists and dental providers. RESULTS: Of the 37 clinical statements, 36 reached consensus or strong consensus, and 1 reached no consensus. Strong consensus was reached that certain clinical and microbiologic features should arouse suspicion for ODS, and that multidisciplinary collaboration between otolaryngologists and dental providers is generally required to diagnose ODS. To diagnose ODS, otolaryngologists should confirm sinusitis mainly based on nasal endoscopic findings of middle meatal purulence, edema, or polyps, and dental providers should confirm dental pathology based on clinical examination and dental imaging. CONCLUSION: Based on multidisciplinary international consensus, diagnosing ODS generally requires otolaryngologists to confirm sinusitis, and dental providers to confirm maxillary odontogenic pathology. Importantly, both dental providers and otolaryngologists should suspect ODS based on certain clinical features, and refer patients to appropriate providers for disease confirmation.

Customized CAD/CAM titanium meshes for the guided bone regeneration of severe alveolar ridge defects: Preliminary results of a retrospective clinical study in humans.

OBJECTIVES: To present the results of guided bone regeneration (GBR) of atrophic edentulous ridges with customized CAD/CAM titanium meshes. MATERIAL AND METHODS: Forty-one patients, presenting with 53 atrophic sites, were enrolled between 2018 and 2019. GBR was obtained with titanium meshes filled with autogenous bone chips and bovine bone mineral (BBM). After a mean of 7 months (range: 5-12 months), meshes were removed and 106 implants placed. After a mean of 3.5 months (range: 2-5 months), implants were uncovered and prosthetic restorations started. The outcomes were vertical and horizontal bone augmentation changes, biological complications and implant survival. RESULTS: Out of 53 sites, 11 underwent mesh exposure: eight of them were followed by uneventful integration of the graft, while three by partial bone loss. The mean vertical and horizontal bone gain after reconstruction was 4.78 ± 1.88 mm (range 1.00-8.90 mm) and 6.35 ± 2.10 mm (range 2.14-11.48 mm), respectively. At the time of implant placement, mean changes of initial bone gain were -0.39 ± 0.64 mm (range -3.1 to + 0.80 mm) and -0.49 ± 0.83 mm (range -3.7 to +0.4 mm), in the vertical and horizontal dimensions, respectively. Reduction of bone volume was significantly higher (p < .001 for both dimensions) in the exposed sites. The mean follow-up of implants after loading was 10.6 ± 6.5 months (range: 2-26 months). The survival rate of implants was 100%. CONCLUSION: Customized titanium meshes can represent a reliable tool for GBR of severely atrophic sites, with simplification of the surgical phases.

A retrospective 10-year mean follow-up of implants placed in ridges grafted using autogenous mandibular blocks covered with bovine bone mineral and collagen membrane.

OBJECTIVES: To report the clinical and radiographic outcomes of patients presenting with edentulous and atrophic ridges and treated with autogenous mandibular bone blocks and rehabilitated with implant-supported prostheses. MATERIALS AND METHODS: From 1997 to 2015, 75 patients presenting with bone defects of the jaws were grafted with autogenous mandibular bone blocks. One-hundred eighty-two implants were placed 4 to 12 months later and loaded 3 to 10 months later: the mean follow-up was 10 years (range: 3-16 years). The following outcomes were recorded: (a) complication rate of the reconstructive procedure; (b) bone graft resorption before implant placement; (c) peri-implant bone resorption; (d) implant-related complications; and (e) implant survival and success rates. RESULTS: Postoperative recovery was uneventful in the majority of patients. An early dehiscence occurred in three patients, but with no significant bone loss, while 3 experienced temporary paraesthesia. The mean vertical and horizontal bone resorption before implant placement was 0.18 mm (standard deviation [SD] = 0.43) and 0.15 mm (SD = 0.42), respectively. The mean peri-implant bone loss ± standard deviation was 1.06 ± 1.19 (range: 0.00-5.05) at patient level and 1.11 ± 1.26 (range: 0.00-5.20) at implant level. Two implants in 2 patients lost integration and were removed; 10 implants in 7 patients developed peri-implantitis, but healed after surgical treatment. The cumulative implant survival and success rates were 98.11% and 85.16%, respectively. CONCLUSION: Implants placed in areas reconstructed with mandibular bone blocks presented survival rates consistent with those obtained for implants placed in native bone.

Odontogenic rhinosinusitis and sinonasal complications of dental disease or treatment: prospective validation of a classification and treatment protocol.

PURPOSE: Odontogenic sinusitis and sinonasal complications of dental disease or treatment (SCDDT) represent a heterogeneous group of conditions that often require multidisciplinary care. The present study aims to prospectively validate a classification and treatment protocol for SCDDT patients. METHODS: One hundred twenty-eight consecutive patients (73 females and 45 males, mean age 52.4 years) affected by SCDDT not responding to dental and medical therapy were classified and surgically treated according to the proposed protocol. The protocol classified patients into three aetiology-based groups (preimplantologic, implantologic, and related to traditional dental diseases and procedures, respectively). The groups were further divided into classes according to the presence of oro-antral communications and/or dislocated dental hardware. Each condition was treated according to the class-related, protocol-defined treatment, by either a transnasal or combined transnasal/transoral approach. All patients were successfully classified according to our protocol. None of the proposed classes were redundant, and no condition fell outside the definitions. RESULTS: The surgical treatment protocol proved to be adequate and effective, in that 125 of the 128 patients completely recovered after surgical treatment. CONCLUSIONS: The term SCDDT and the consequent classification proposed by the authors appear, therefore, to be nosologically correct. Furthermore, the protocol-related proposed treatment appears to be clinically sound, with a success rate nearing 98%.

Maxillary Sinus Membrane Elevation Using a Special Drilling System and Hydraulic Pressure: A 2-Year Prospective Cohort Study.

The purpose of this study was to evaluate clinical and radiologic outcomes using a newly developed device for maxillary sinus membrane elevation. Patients with a residual bone height of at least 3 mm were enrolled. Crestal sinus lift elevation and sinus graft were performed using the crestal approach sinus (CAS) kit. Graft was avoided if the residual bone crest was ≤ 2 mm less than the length of the planned implant. Outcome measures were implant and prosthesis failure, any biologic or technical complications, and marginal bone loss (MBL). A total of 35 consecutive patients underwent 49 crestal elevations of the sinus membrane. All the implants were followed for at least 2 years after placement (mean follow-up 37.3 months; range 24 to 54 months). No implants or prostheses failed during follow-up, and no membrane tears or other intraoperative or postoperative adverse events were observed. At the 2-year follow-up, mean MBL was 0.33 ± 0.24 mm (95% confidence interval: 0.08 to 0.30 mm). A total of 32 implants were placed after filling the sinus with anorganic bovine bone, while 17 implants were placed without grafting the sinus. Post-hoc analysis was performed using the sinus grafting remodeling index (SGRI) to evaluate radiographically the tissue remodeling patterns. The SGRI was statistically significantly higher when the sinus was grafted (P = .000). The CAS kit may provide a new option for minimally invasive crestal sinus surgery. Long-term randomized controlled trials with larger sample size are needed to confirm these preliminary results.

Dental implants placed in severely atrophic jaws reconstructed with autogenous calvarium, bovine bone mineral, and collagen membranes: A 3- to 19-year retrospective follow-up study.

OBJECTIVES: To present the clinical, radiographic, and patient-related outcomes of patients presenting with severely resorbed ridges reconstructed with autogenous calvarial bone blocks and rehabilitated with implant-supported prostheses. MATERIAL AND METHODS: From 1998 to 2014, 72 patients presenting with severe bone defects were reconstructed with autogenous calvarial bone blocks covered with bovine bone mineral granules and collagen membranes. Four to 9 months later, 330 implants were placed and loaded 3-9 months later. The follow-up ranged from 3 to 19 years (mean: 8.1 years). The following parameters were recorded: (a) complication rate of the reconstructive procedure; (b) bone resorption before implant placement; (c) implant survival rate and implant-related complications; (d) peri-implant bone resorption; and (e) patient's satisfaction inquired with a dedicated questionnaire. RESULTS: No patients developed severe complications, such as complete loss or resorption of the grafts. A dehiscence occurred in six patients, which developed a mild graft resorption. The mean peri-implant bone resorption before implant placement was 0.13 mm (SD ± 0.71). All patients received the planned number of implants. Three patients were lost during the follow-up. The survival rate of implants at the end of the observation period was 98.5%. The mean peri-implant bone resorption ranged from 0.00 to 4.87 mm (mean: 1.11 mm). At last, 90% of the patients were very satisfied as regards the treatment received. CONCLUSIONS: Results from this study suggested that: (a) bone volume in the areas reconstructed with calvarial grafts was stable over time; (b) survival rates of implants were consistent with those reported for implants placed in native bone; (c) patient's satisfaction was high.

Horizontal bone-augmentation procedures in implant dentistry: prosthetically guided regeneration.

The rehabilitation of partially or totally edentulous patients with implant-supported prostheses has become routine, with excellent long-term outcome. A proper implant position is mandatory to achieve good functional and esthetic outcome and may require an adequate amount of alveolar bone and surrounding soft tissue. When this is lacking because of atrophy, sequelae of periodontal disease, traumas or congenital malformations, increased bone volume and/or keratinized mucosa can be obtained by guided bone regeneration, bone-grafting techniques and alveolar bone expansion. This article presents an evidence-based, prosthetically driven approach for the treatment of edentulous ridges with horizontal defects. The classification of bony defects, the main augmentation techniques, the selection criteria among different surgical procedures for different types of bony defects, and the advantages, disadvantages and limitations of each technique, are described in detail.

Iliac Crest Fresh-Frozen Allografts Versus Autografts in Oral Pre-Prosthetic Bone Reconstructive Surgery: Histologic and Histomorphometric Study.

PURPOSE: The aim of this work was to compare histologically bone biopsies obtained during dental implant placement in atrophic jaws reconstructed with fresh-frozen bone (FFB) or autologous bone blocks. MATERIALS AND METHODS: Twenty partially or totally edentulous patients were treated either with iliac crest FFB grafts (14 patients; group A) or with iliac crest autografts (6 patients; group B). Seven to 9 months later, dental implants were placed in the reconstructed jaws and bone biopsies were harvested. RESULTS: The reconstructive procedure was uneventful in 9 patients of group A and in all patients of group B. Samples from both groups did not show relevant differences concerning the proportion of lamellar bone, newly formed bone, and bone marrow. In group A, the decreasing proportion of blood vessels from the apical to the coronal portion, the larger amount of lacunae in the apical portion, and the fewer vessels in the coronal portion than in group B evoke an effort of the host bone to "integrate" the graft from the apical portion. CONCLUSIONS: FFB cannot be considered as successful and safe in alveolar bone reconstruction as autogenous bone grafting.

One-Step Maxillary Sinus Augmentation in Association With Endoscopic Sinus Surgery: Case Series and Review of the Literature.

INTRODUCTION: Sinonasal anatomical anomalies and inflammatory conditions may reduce success rates of maxillary sinus elevation (MSE) procedures used to allow implant placement in the atrophic posterior maxilla. Approaches combining endoscopic sinus surgery (ESS) and MSE were firstly proposed by our group and have already been described in the literature. This article aims to re-evaluate the procedure in a larger sample of patients comparing results and indications with the pertaining literature. MATERIALS AND METHODS: Thirty-three patients (19 men and 14 women, mean age 52.79 ± 11.95 years) underwent combined ESS/MSE with 48 MSE procedures performed. RESULTS: No intraoperative complications were reported. An uneventful and complete graft integration was obtained after 6 months in all but one patient. All patients completed prosthetic rehabilitation within 9 to 12 months. CONCLUSION: Combined ESS and MSE has proven to be a safe and reliable procedure, which can be proposed to selected patients presenting with reversible sinonasal contraindications to MSE and should be no more considered an experimental procedure.

Retrobulbar hemorrhage during or after endonasal or periorbital surgery: what to do, when and how to do it.

Retrobulbar hemorrhage (RBH) is an uncommon complication of endoscopic sinus surgery or periorbital surgery consisting in an accumulation of blood within the orbit posteriorly to the eyeball. It must be treated within 90-100 minutes to avoid irreversible visual loss. The present paper tries to pinpoint the key steps in diagnosis and treatment of RBM.On the wake of a new case, the authors review and update their clinical experience and propose a step-by-step protocol to diagnose and to treat RBH developing under different circumstances: during endoscopic sinus surgery, during periorbital surgery, immediately after the surgery, in the awakening room, or postoperatively in the ward.A therapeutic ladder is proposed that starts with lateral canthotomy and inferior cantholysis and progresses to a lower lid transconjunctival incision with retrocaruncular extension.Based on our experience, the proposed guidelines are effective in diagnosing and treating RBH. They allow to preserve vision and minimize reliquates of this rare and dangerous surgical emergency.