Primary Stability of Trabecular Metal Implant in Comparison to Fully Threaded Implants: In Vitro Study Simulating Immediate Implant Placement.

The aim of this study was to evaluate primary stability of 3.7-mm diameter porous tantalum Trabecular Metal (TM) implant, and compare it to fully threaded implants, in the in vitro model of immediate implant placement in the anterior maxilla. A total of 60 implants were placed into bovine ribs using surgical guides. Implants were divided in 3 groups of 20 according to the design: TM, Tapered Screw-Vent (TSV), and NobelReplace. To simulate immediate placement in anterior maxilla, implants were placed under a sharp angle toward the ribs, not fully submerged. Placement angle of 20.7° was calculated after analysis of 148 virtually planned implants on cone beam computerized tomography scans of 40 patients. No statistically significant difference in implant stability quotient (ISQ) was found between TM (65.8 ± 2.6), TSV (64.7 ± 2.7), and NobelReplace (64.6 ± 2.7). TSV implants achieved higher insertion torque (37.0 ± 4.8 Ncm) than TM (32.9 ± 5.2 Ncm) and NobelReplace (23.2 ± 3.3 Ncm). TSV had the shortest insertion time of 13.5 ± 1.0 seconds, compared to 15.2 ± 1.2 seconds for TM, and 19.7 ± 1.7 seconds for NobelReplace. Pearson correlation analysis showed significantly correlated insertion torque and ISQ values for TM group (P = .011, r = .56), a nonsignificant correlation was found for TSV and NobelReplace. The results of the present study indicate that TM implant can achieve good primary implant stability in insertion torque and resonance frequency analysis.

Bone Ring Allograft: Digitally Guided Placement in the Anterior Esthetic Area. A Retrospective Case Series.

This case series demonstrates a surgical technique consisting of a digitally planned and guided placement of a bone ring allograft and implant in the anterior esthetic zone. Eight consecutive patients with horizontal and vertical defects in the anterior maxilla underwent augmentation with a commercially available bone ring allograft and simultaneous implant placement using two digital guides. After 6 to 8 months, implants were uncovered and restored with a screw-retained prosthesis. Follow-up periods ranged from 8 to 24 months. All eight implants met predefined success criteria with no adverse events. Radiographic measurements demonstrated stable peri-implant bone levels 1 year after implantation, with bone loss ranging from 0.0 to 1.4 mm. All patients were satisfied with the total treatment time, postsurgical healing, and final esthetic outcome. This case series describes a one-stage procedure in which a bone ring allograft and implant are simultaneously placed for treatment of a severely defective ridge in the anterior maxilla. The technique appears to be reliable for use in the esthetic zone, with minimal first-year loss of peri-implant bone. In combination with a digital guide, accurate implant and bone ring placement can be achieved, resulting in reduced chair time and fewer surgical procedures for the patient.

A novel fully tapered, self-cutting tissue-level implant: non-inferiority study in minipigs.

OBJECTIVES: To assess the osseointegration and crestal bone level maintenance of a novel fully tapered self-cutting tissue-level implant for immediate placement (test) compared to a clinically established tissue-level implant (control) in moderate bone quality. MATERIALS AND METHODS: Test and control implants were compared in 3 groups, i.e., small-, medium-, and large-diameter implants in an edentulous mandibular minipig model with moderate bone quality after 12 weeks of healing. Histometrically derived bone-to-implant contact (BIC) and first bone-to-implant contact (fBIC) were subjected to statistical non-inferiority testing. Maximum insertion torque values in artificial bone were assessed for comparison. RESULTS: BIC values for the tests and control implants for all 3 diameters were comparable and non-inferior: small diameter (61.30 ± 10.63% vs. 54.46 ± 18.31%) (p=0.99), medium diameter (60.91 ± 14.42 vs. 54.68 ± 9.16) (p=0.55), and large diameter (45.60 ± 14.67 vs. 52.52 ± 14.76) (p=0.31). fBIC values for test implants were higher and non-inferior compared to control implants in all three groups. Test implants further showed distinctly higher maximum insertion torque values compared to control implants. CONCLUSION: The investigated novel tissue-level implant is able to achieve high levels of primary and secondary implant stability under simultaneous preservation of crestal bone levels. This qualifies the studied implant as an attractive candidate for immediate placement in bone of limited quality. CLINICAL RELEVANCE: This pilot pre-clinical study investigated a novel tissue-level implant for immediate placement. With the aim of translating the studied prototype into clinical application pre-clinical models, procedures and controls have been chosen with the aim of reflecting its future clinical indication and use.

Quantifying the Emergence Profile Contour for Immediate Provisionalization: A Proposed Mathematical Model.

Identifying the ideal position of the final restoration prior to implant surgery is essential for optimal esthetics. The study of the emergence contour design of implant restorations has been limited. The aim of this report is to compile the factors that affect the final esthetic outcome and integrate those factors into an easy-to-use model. This geometric model includes a linear distance created by the placement of an implant platform in relation to the free gingival margin and a circle representing the emergence profile to create an emergence curve. If this model is evaluated and available, a practitioner can make appropriate decisions based on 3-dimensional immediate implant concepts.

A Novel Xenograft Bone Substitute Supports Stable Bone Formation in Circumferential Defects Around Dental Implants in Minipigs.

PURPOSE: The aim of this study was to evaluate and compare bone growth and implant integration in circumferential defects with two commercially available bone substitutes (demineralized bovine bone mineral [DBBM]). MATERIALS AND METHODS: Circumferential defects were created in the mandibles of minipigs (n = 10), and Bone Level Tapered implants (Straumann Roxolid with SLActive surface) were placed. The defects (4-mm-deep circumferential defect, 2 mm around each implant) were augmented with either sintered bovine bone mineral (test, cerabone) or natural bovine bone mineral (control, Bio-Oss). Bone formation and tissue composition in augmented sites were histomorphometrically assessed after 8 and 12 weeks of healing time (n = 5 each), respectively, in terms of the percentage of area of newly formed bone to total area, bone-to-implant contact (BIC), and crestal bone height relative to the implant shoulder (first bone-to-implant contact [fBIC]). RESULTS: Bone formation in all defect sites was adequate and equivalent for both groups at individual healing time points. The amount of residual graft material was comparable in both groups after 8 and 12 weeks, with no significant resorption in either group. The mean newly formed bone area in the test group amounted to 46.7% ± 5.1% and 48.7% ± 4.0% after 8 and 12 weeks vs 47.0% ± 4.8% and 47.8% ± 7.3% in the control group, respectively. BIC and fBIC as individually assessed for the lingual and buccal aspects were comparable at both healing time points without any statistically significant differences between the groups. A slightly greater variability of fBIC was observed within the test group. CONCLUSION: The results of this study indicate that test and control materials both represent viable bovine bone graft material that equivalently support the formation of new and stable bone volume specifically when used for simultaneous augmentation around implants.

AAID White Paper: Management of the Dental Implant Patient During the COVID-19 Pandemic and Beyond.

The scientific community's understanding of how the SARS-CoV-2 virus is transmitted and how to best mitigate its spread is improving daily. To help protect patients from acquiring COVID-19 from a dental office nosocomial infection, many state or local governments have classified dental treatments as "nonessential" and have paused routine dental care. Dentists have been instructed to perform only procedures designated as emergencies. Unfortunately, there is not a good understanding of what a dental emergency is among governmental leaders. What a government agency may perceive as an elective procedure may be seen as "essential" by the dental clinician responsible for maintaining the oral health of the patient. Each dental specialty understands the effects delayed care has on a patient's oral and systemic health. Dentistry has made extensive progress in improving oral health through prevention of the dental emergency. The dental profession must work together to prevent the reversal of the progress dentistry and patients have made. This American Academy of Implant Dentistry (AAID) White Paper discusses what COVID-19 is and how it impacts dental treatments, presents guidelines for dentistry in general and for dental implant related treatments, specifically. Recommendations for implant dentistry include the following: (1) what constitutes a dental implant related emergency, (2) how patients should be screened and triaged, (3) what personal protective equipment is necessary, (4) how operatories should be equipped, (5) what equipment should be used, and (6) what, when, and how procedures can be performed. This paper is intended to provide guidance for the dental implant practice so patients and dental health care providers can be safe, and offices can remain open and viable during the pandemic.

A Modified Technique of Tacking Acellular Dermal Matrix to Increase Keratinized Mucosa Around Dental Implants as an Alternative to a Free Gingival Graft: A Case Report.

INTRODUCTION: Free autogenous graft was the gold standard to increase the keratinized mucosa (KM) and vestibular depth. The major downfall of this technique is the postoperative morbidity at the donor site. The purpose of this case report is to demonstrate a modified technique using acellular dermal matrix (ADM) to increase the KM around implants to achieve faster healing with less postoperative morbidity. CASE PRESENTATION: Patient presented with inadequate keratinized tissue band and shallow vestibule at submerged implant sites bilaterally. Initially, surgical procedure of vestibuloplasty in conjunction with free gingival graft (FGG) was performed at one side. However, patient opted for the allograft as a substitute for the other side due to the postoperative discomfort from palatal donor site. On the left side, the FGG procedure was performed in a conventional way stabilizing with sutures. On the right side, the ADM was stabilized with tacks only at recipient site and left exposed. The new vestibule was established and stabilized with tacks.  A significant gain of KM and vestibule depth was observed at the site of using ADM when compared with baseline. For the site of using FGG, KM was increased. However, the vestibule was rebounded compared with the site of using ADM with tacks. CONCLUSIONS: The use of ADM stabilized with tacks is a predictable procedure that can increase KM and establish stable vestibule around dental implants. It can lead to less chair time, faster healing, and reduced postoperative morbidity compared with autogenous soft tissue graft.

Decontamination of the Infected Implant Surface: A Scanning Electron Microscope Study.

A number of treatment options have been explored for peri-implantitis. Seven rough-surfaced implants that failed from peri-implantitis were retrieved. Surfaces were treated by different methods: saline, chlorhexidine, citric acid, 35% phosphoric acid etch gel, hydrogen peroxide, implantoplasty, airborne-particle abrasion, laser, and titanium brush. Implants were observed under scanning electron microscopy. Chemical agents failed to remove any biologic debris. Airborne-particle abrasion, laser, and titanium brush removed part of the biologic debris, and implantoplasty showed complete biologic debris removal. In ex vivo failed implants, implantoplasty showed complete disturbance and removal of bacterial biofilm.

The Novel Periosteal Flap Stretch Technique: A Predictable Method to Achieve and maintain Primary Closure in Augmentative Procedures.

BACKGROUND: Correct soft tissue management and achieving tension-free primary closure are pre-requisites for the success of bone augmentation procedures. Several techniques have been developed to facilitate a passive soft tissue primary closure. However, the current techniques are highly invasive and require advanced surgical skills. Hence, the present case series report will describe a novel and simple flap management technique. METHODS: The Periosteal Flap Stretch technique was utilized in bone augmentation procedures for four patients who presented with horizontal and vertical alveolar ridge deficiencies in the anterior maxilla, anterior mandible, posterior mandible, and posterior maxilla. This technique is performed using a blunt surgical curette that engages the periosteum of the mucosa below the mucogingival line of the full-thickness flap and stretches the periosteum in a coronal and outward direction, which results in stretching of the flap without the need for vertical or periosteal releasing incisions. RESULTS: Healing was uneventful for four all cases. No membrane exposure, no soft tissue dehiscence, or any other complications were observed during the six-months healing period after the respective bone augmentation procedures of cases. CONCLUSIONS: The Periosteal Flap Stretch technique is a novel and simple technique that facilities achieving passive and predictable primary soft tissue closure.

Treatment of Atrophic Ridges with Titanium Mesh: A Retrospective Study Using 100% Mineralized Allograft and Comparing Dental Stone Versus 3D-Printed Models.

This multicenter study retrospectively evaluated implant survival and bone growth in atrophic ridges that were augmented with titanium mesh and 100% mineralized solvent-dehydrated bone allografts (MSDBA). A secondary objective of this study was to evaluate differences in outcomes by diagnostic model type. Titanium mesh was shaped on a diagnostic wax-up of the patient's jaw: Twenty-three patients (Group 1) had wax-ups on dental stone models, and 16 patients (Group 2) had wax-ups on models fabricated with three-dimensional (3D) printing technology. Clinical and histologic data were analyzed. The average bone gain ranged from 5.94 to 6.91 mm horizontally and 5.76 to 6.99 mm vertically and was not significantly different between the two model groups (P > .05). Implant survival was 100% after 18 to 48 months. Although model type had no significant influence on outcomes, 3D-printed models allowed for faster surgery and served as visual aids for patient education.

Crestal Bone and Keratinized Tissue Around 3.0-mm Laser-Microtextured Dental Implants After 1 Year in Function: A Case Series.

The purpose of this case series was to evaluate peri-implant tissues in 10 patients at 1 year after placement of a tapered 3.0-mm laser-microtextured dental implant (Laser-Lok, BioHorizons) using a two-stage approach. Clinical and radiographic measurements were assessed. Keratinized tissue at the facial surfaces of each implant had a slight increase of 0.73 mm (95% confidence interval [CI], P = .058), and marginal bone levels had significant increase of 1.85 mm (95% CI, P = .005) at 1 year compared to baseline. These data suggest that 3.0-mm laser-microtextured implants demonstrate stable or improved soft and hard tissue parameters at 1 year postloading.

Osseointegration of Superhydrophilic Implants Placed in Defect Grafted Bones.

PURPOSE: Only limited information on the effect of implant surface hydrophilicity in conjunction with simultaneous bone augmentation is available. In this study, new bone growth around implants with a superhydrophilic modSLA (SLActive) and hydrophobic SLA (SLA) surface were compared in circumferential defects when grafted in conjunction with mineralized cancellous bone allograft (MCBA, maxgraft) or sintered bovine bone mineral (SBBM, cerabone). MATERIALS AND METHODS: The osseointegration and bone formation in circumferential defects in minipig mandibles around Straumann Roxolid, Ø 3.3 mm, length 8 mm; either SLA or SLActive, were evaluated. Following implant placement, the 2-mm circumferential defects around the implants were filled with MCBA or SBBM. Distance from implant shoulder to first bone-to-implant contact (f-BIC), percentage of bone-to-implant contact (BIC), and bone aggregate percentage (amount of new bone and remaining graft) within the defect area were evaluated after 8 weeks of healing. RESULTS: In the SBBM group, lingual fBIC and buccal BIC were significantly lower for SLA (mean -0.404 ± 0.579 mm for modSLA versus -1.191 ± 0.814 mm for SLA, P = .021 and mean 62.61% ± 9.49% for modSLA versus 34.67% ± 24.41% for SLA, P = .047, respectively). Bone aggregate percentage was significantly higher for modSLA versus SLA implants in SBBM (77.84% ± 6.93% versus 64.49% ± 13.12%; P = .045). The differences between implant surfaces in MCBA showed a similar trend but were less pronounced than in the SBBM group and did not reach a statistically significant level. CONCLUSION: The results suggest that implants with a superhydrophilic modSLA surface are more conducive to faster osseointegration even in conjunction with simultaneous bone grafting procedures.

Soft Tissue Closure of Grafted Extraction Sockets in the Anterior Maxilla: A Modified Palatal Pedicle Connective Tissue Flap Technique.

Localized ridge resorption, the consequence of socket collapse, following tooth extraction in the anterior maxilla can adversely affect esthetics, function, and future implant placement. Immediate grafting of extraction sockets may help preserve natural ridge contours, but a lack of available soft tissue can compromise the final esthetic outcome. The presented modified rotated palatal pedicle connective tissue flap is a useful technique for simultaneous soft tissue coverage and augmentation of grafted sockets to improve esthetic outcome. This article delineates its advantages through the presentation of a four-case series using this new technique.

Primary Oral Melanoma - A Non-Surgical Approach to Treatment via Immunotherapy.

INTRODUCTION: Malignant melanoma is an aggressive form of cancer that commonly affects skin and rarely affects the oral cavity. With poorly understood risk factors and an often-asymptomatic presentation, oral melanoma is difficult to detect until advanced stages of disease. Treatment for oral melanomas has been primarily surgical, and survival rates have been low. However, in recent years, immunotherapy has shown much promise with increased patient survival. CASE PRESENTATION: A 49-year-old male was referred by his primary dentist to a periodontal clinic for management of an alleged unresolved periodontal abscess. The patient had completed full-mouth scaling and root planing and consequently developed a large mass in the left posterior maxilla. Incisional biopsies were performed in multiple locations in the maxillary gingivae, and interpretation revealed atypical melanocytic proliferation and primary melanoma. After appropriate work-up, the patient was treated with two different immunotherapy agents: 1) ipilimumab and 2) pembrolizumab. Results after immunotherapy were favorable, and the tumor significantly decreased in size with no major adverse effects. The response was so strikingly positive that the need for surgical removal was almost eliminated. At the present time, it is unknown whether the patient will receive any surgical treatment barring a recurrence. CONCLUSIONS: Oral mucosal pigmentation is a finding commonly encountered by dentists during clinical patient examinations. However, proper diagnosis of pigmented lesions, especially those associated with malignancy, requires investigations that go beyond clinical examination.

A Retrospective Survival Study of Trabecular Tantalum Implants Immediately Placed in Posterior Extraction Sockets Using a Flapless Technique.

A retrospective review of patient records was conducted in a single private practice to evaluate the efficacy of immediately placing a novel implant design in posterior jaw locations using a flapless technique. Forty-two patients (22 males, 20 females) with a mean (SD) age of 60.2 (7.6) years (range = 31-68) presented with 1-2 nonrestorable molar (maxillary = 14; mandibular = 8) or premolar (maxillary = 20; mandibular = 1) teeth compromised by periodontal disease, endodontic failure, root resorption, root fracture, or severe caries. Most patients (78.6%) had moderate (66.7%) or severe (11.9%) periodontitis. Other comorbidities included smoking (14.3%) and controlled diabetes mellitus (11.9%). After atraumatic extraction, teeth were immediately replaced with a total of 44 trabecular tantalum implants (Trabecular Metal Implants, Zimmer Biomet Dental) (diameter = 3.7-4.7 mm; length = 10-13 mm). Sites requiring augmentation were treated with 3 types of small-particle (250-1000 µm), mineralized, solvent-dehydrated, allografts (Puros) based on location: cortical for crestal sinus grafts, cancellous for peri-implant voids in thick tissue biotypes, or cortical-cancellous (70:30) mix for peri-implant voids in thin tissue biotypes. Cortical particulate was used when slower resorption would help maintain graft volume for esthetics or implant support. Grafts were covered with resorbable bovine pericardium membranes (CopiOs, Zimmer Biomet). Cumulative implant survival and success rates were 97.7%, respectively, with a mean (±SD) follow-up time of 25.0 ± 12.1 months (range = 4-48). One asymptomatic implant failed to osseointegrate. Within the limitations of this study, implants achieved outcomes comparable to conventionally placed and restored single-tooth implants in anterior jaw locations.

Maxillary Sinus Grafting With Biphasic Bone Ceramic or Autogenous Bone: Clinical, Histologic, and Histomorphometric Results From a Randomized Controlled Clinical Trial.

PURPOSE: The present, randomized, controlled clinical trial compared the histologic and histomorphometric results from maxillary sinus augmentation with either biphasic calcium phosphate (BCP) (60% hydroxyapatite and 40% ß-tricalcium phosphate) or autogenous bone (AB) as bone-grafting materials. MATERIAL AND METHODS: Ten patients received bilateral sinus elevation surgery with intraoral AB chips (control group) on one side and BCP (test group) on the contralateral side. After a healing period of 6 to 8 months, implant sites were created and trephine cores were harvested for histological and histomorphometric analysis of the grafted areas. RESULTS: The histological examination of biopsies showed BCP particles interconnected by bridges of a vital newly formed bone. Histomorphometry demonstrated that the amount of newly formed bone in the control group (36.8%) was significantly greater than that in the BCP (28.2%) group (P = 0.0032). BCP and AB cores revealed an average of residual graft particles of 32.9% and 4.8%, respectively. The average percentage of soft tissue components was 38.9% in the BCP cores and 58.4% in the AB cores. CONCLUSIONS: Based on our findings, the amount of vital bone formation was significantly higher for AB than that for BCP. However, BCP seemed to be a biocompatible and osteoconductive material that can be used with success as a bone substitute in maxillary sinus procedures.

Effect of patient age awareness on diagnostic agreement of chronic or aggressive periodontitis between clinicians; a pilot study.

BACKGROUND: The aim of this pilot study was to test whether diagnostic agreement of aggressive and chronic periodontitis amongst Board Certified Periodontists, is influenced by knowledge of a patient's age. In 1999 at the International World Workshop age was removed as a diagnostic criteria for aggressive periodontitis. The impact of this change on the diagnostic reliability amongst clinicians has not yet been assessed. METHODS: Nine periodontal case reports were twice presented to sixteen board certified periodontists, once with age withheld and again with patient age provided. Participants were instructed to choose a diagnosis of Chronic Periodontitis or Aggressive Periodontitis. Diagnostic agreement was calculated using the Fleiss Kappa test. RESULTS: Including the patients' age in case report information increased diagnostic agreement (the kappa statistic) from 0.49 (moderate agreement) to 0.61 (substantial agreement). CONCLUSION: These results suggest that knowledge of a patients' age influenced clinical diagnosis, when distinguishing between aggressive periodontitis and chronic periodontitis, which may in turn impact treatment decision-making.

Clinical and Histological Evaluation of Ceramic Matrix in a Collagen Carrier for Socket Preservation in Humans.

INTRODUCTION: A case series was used to evaluate the efficacy and predictability of a ceramic matrix in a putty-like collagen carrier in immediate extraction sockets. METHODS: A single failing tooth was atraumatically extracted from each of 10 subjects. The sockets were debrided and grafted with ceramic matrix in a putty-like collagen carrier (15% hydroxyapatite, 85% ß-tricalcium phosphate complex). A bovine pericardium membrane was draped over the graft site and a tension-free primary closure was obtained. After 6 months of healing, a trephine biopsy was taken from the center of each graft and a dental implant was placed. Two subjects were withdrawn from the study and were considered treatment failures. One of them moved to another state and the second exhibited delayed healing that required debridement of the grafting material from the socket. RESULTS: After 6 months follow-up, there was a mean reduction of ridge width of 1.667 mm and mean reduction of ridge height of 0.483 mm after graft healing and integration. Over a 24-month follow-up, mean new bone fill was 40.25% and implant osseointegration was 100%. CONCLUSION: Ceramic matrix in a putty-like collagen carrier maintained ridge dimensions and, despite ongoing bone turnover, produced adequate mineralized tissue that enabled implant placement at 6 months.

Demineralized bone matrix in extraction sockets: a clinical and histologic case series.

PURPOSE: To evaluate its efficacy and predictability in immediate extraction sockets, this case series used demineralized bone matrix in a puttylike carrier (DBM putty) with and without mineralized bone chips. Each preparation was made from the long bones of the same tissue donor; the only excipient material was water. MATERIAL AND METHODS: A single failing tooth was atraumatically extracted from each study subject, and the socket was debrided. Intact sockets were grafted with DBM putty (n = 6), and sockets with buccal defects were grafted with DBM putty with bone chips (n = 6). A bovine pericardium membrane was draped over the graft site, and tension-free primary closure was obtained. After 6 months of healing, a trephine biopsy was taken from the center of each graft, and then, a dental implant was placed. Two subjects were withdrawn, and histologic data could not be obtained from 2 other patients. RESULTS: Mean new bone fill was 40.28% for DBM putty (n = 5) and 44.60% for DBM putty with bone chips (n = 4). CONCLUSIONS: Both preparations maintained ridge dimensions and, despite ongoing bone turnover, produced adequate mineralized tissue that enabled implant placement at 6 months. This finding warrants further research.