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Purpose/objectives: The objectives of this study were to assess the influence of learner‐ and education‐related factors on standardized in‐service examination performance and determine whether in‐service examination scores predict residency outcomes. Methods: American Academy of Periodontology (AAP) In‐service Examination (AIE) scores from 10 periodontics residency classes at a single center were recorded and compared against a panel of learner‐ and education‐related variables using multiple linear regression models. Defined residency outcome measures were analyzed against AIE scores using binomial logistic regression. Results: No evaluated learner‐ or education‐related variable was a statistically significant predictor of AIE score in this study sample. Likewise, AIE score was not a statistically significant predictor of any assessed residency outcome. Conclusions: The AAP has performed a tremendous service to periodontics residents and programs by marshaling the leadership and expertise necessary to offer a professionally constructed assessment instrument. However, in the current study, no relationship could be identified between AIE score and any outcome, including first‐attempt board certification. The AAP In‐service Committee appears well situated to provide additional leadership focusing on exam implementation, which may enhance AIE value in competency decision making. [ABSTRACT FROM AUTHOR]

Background: The physiologic bone remodeling accompanying tooth extraction is a phenomenon well described in the dental literature. Extraction sockets severely compromised by local infection, trauma, iatrogenesis, or other factors may exhibit enhanced reduction in alveolar dimensions during healing. The purpose of this report is to present an alveolar ridge preservation (ARP) protocol specifically intended for use at severely compromised sites. Methods: Seven patients presented to the Department of Periodontics, Army Postgraduate Dental School, Fort Gordon, Georgia, requiring extraction of teeth with partial or near‐complete loss of the facial/buccal cortex. At each site, a cross‐linked bovine collagen membrane was used to prevent collapse of the facial/buccal soft tissue and maintain space, a freeze‐dried bone allograft was applied in the socket, and a dense polytetrafluoroethylene membrane covered the occlusal aspect. Results: All sites healed uneventfully and resulted in favorable alveolar ridge dimensions for implant placement. Conclusion: Few authors have proposed specific ARP methods for managing severely deficient extraction sockets. The predominant recommendation has been staged reconstruction of the site applying hard and soft tissue augmentation. Observations reported herein suggest that staged reconstruction is avoidable at some extraction sockets exhibiting severe alveolar compromise. Controlled clinical investigation of this protocol appears warranted. Key points: Few authors have proposed alveolar ridge preservation (ARP) methods specifically intended for use at severely compromised extraction sockets.The prevailing recommendation at such sites is a staged protocol involving tooth extraction with delayed hard and soft tissue augmentation.The presented bilaminar ARP technique may eliminate the need for staged reconstruction at some severely compromised extraction sockets. [ABSTRACT FROM AUTHOR]

Objectives: In periodontology, it is widely recognized that evidence characterizing the incidence and effect of treatment complications is lacking. The objective of this study was to assess the influence of operator‐, procedure‐, patient‐, and site‐associated factors on intraoperative and postoperative complication occurrence. Material and Methods: A single investigator reviewed records of patients treated by eight periodontics residents from July 2018 through June 2022. For each procedure, the investigator recorded each intraoperative and postoperative complication or indicated that no complication had occurred. These outcomes were analyzed against a panel of explanatory covariates. In addition, the severity of each postoperative complication was assessed using a standardized grading system. Results: A total of 1135 procedures were included in the analysis. Intraoperative and postoperative complications were identified in 2.8% and 15.2% of procedures, respectively. The most common intraoperative complications were Schneiderian membrane perforation (1.3%) and gingival flap perforation/tear (1%), and the most common postoperative complications were dentin hypersensitivity (2.6%), excessive pain (2.5%), and infection (2.2%). Subepithelial connective tissue graft (odds ratio [OR]: 3.2, 95% confidence interval [CI]: 1.6, 6.1; p <.001), guided bone regeneration (OR: 3.0, 95% CI: 1.4, 6.5; p =.004), and guided bone regeneration with implant placement (OR: 3.1, 95% CI: 1.3, 7.6; p =.011) were associated with higher odds of postoperative complication, whereas lateral sinus elevation (OR: 102.5, 95% CI: 12.3, 852.9; p <.001), transalveolar sinus elevation (OR: 22.4, 95% CI: 2.2, 224.5; p =.008), open flap debridement (OR: 36.4, 95% CI: 3.0, 440.7; p =.005), and surgically facilitated orthodontic therapy (OR: 20.5, 95% CI: 1.2, 358.4; p =.039) were associated with higher odds of intraoperative complication occurrence. Conclusions: Consistent with previous reports, procedure type appears to be the predominant factor driving complication occurrence. As analyses of treatment complications increase, individualized risk‐benefit assessments will become progressively meaningful for patients. [ABSTRACT FROM AUTHOR]

Background: Delivery of a high‐quality provisional restoration at a maxillary anterior immediate implant site enhances patient‐centered outcomes and promotes development of favorable hard and soft tissue architecture. The purpose of this report is to present a protocol relying upon compatible guided surgery and laboratory systems for fabrication of a custom provisional crown prior to immediate implant surgery in the esthetic zone. Methods and Results: A female patient, aged 33 years, presented to the Army Postgraduate Dental School, Fort Gordon, Georgia, with an unfavorable prognosis for tooth #9. The patient elected extraction with immediate implant placement. Prior to the surgery, we utilized a cone‐beam computed tomography volume, stone models, implant planning software, and an implant indexing system to fabricate a custom provisional crown. Following extraction of tooth #9 and immediate implant placement, the provisional crown exhibited excellent fit and finish, requiring virtually no chairside adjustment. We noted minimal change in baseline mucosal contours throughout the healing phase. Conclusion: The clinical/restorative protocol described in this report assured accurate three‐dimensional implant positioning and permitted indirect fabrication of a high‐quality custom provisional crown in advance of surgery. The laboratory workflow—which dental technicians/auxiliaries can master—has the potential to shorten surgery, enhance treatment outcomes, and increase patient satisfaction. Key points: Why is this case new information? This report provides a stepwise workflow guiding indirect fabrication of a custom provisional crown prior to immediate implant placement. What are the keys to successful management of this case? The described technique requires compatible laboratory and guided surgery systems to assure that the restoration accounts for the three‐dimensional position and timing of the implant. What are the primary limitations to success in this case? Dental technicians/auxiliaries can master this protocol and independently produce high‐quality provisional implant restorations under supervision, potentially enhancing practice efficiency. However, practitioners should provide adequate staff training to optimize reliability and quality. [ABSTRACT FROM AUTHOR]

Focused clinical question: What factors identify the optimal bone augmentation techniques for managing slight, moderate, and severe horizontal alveolar ridge deficiency (ARD) at dental implant sites? Summary: Horizontal ARD is a concern at a high proportion of sites receiving dental implants, and clinicians have developed a variety of surgical procedures to address such defects. In a particular case, selection of the optimal treatment may depend predominantly on defect severity, location (anterior versus posterior), and configuration (contained versus noncontained). This report provides a framework for selecting an augmentation method when presented with a slight, moderate, or severe horizontal ARD at a site requiring dental implant placement. Conclusion: Multiple treatment options are available for planned implant sites exhibiting horizontal ARD; severe posterior and slight anterior defects intuitively call for different approaches. Although rigid guidelines for selecting the optimal augmentation method do not exist, some techniques are poorly suited for esthetically demanding sites. A framework considering defect severity, location, and configuration may help guide clinical decisions on this topic. [ABSTRACT FROM AUTHOR]

Focused Clinical Question: Under what circumstances may a clinician consider dental implant placement at a site exhibiting a focal high or mixed density (HMD) osseous lesion radiologically? Summary: Some conditions and pathologic entities exhibiting high and mixed density radiological appearance pose low risk for dental implant failure or complications following implant surgery. However, other lesions represent contraindications to implant placement, and implant surgery at such sites can result in severe morbidity. Conclusion: Potential implant sites exhibiting focal HMD osseous lesions/conditions present varying levels of risk. In most cases, optimal management will include advanced imaging of the site, multidisciplinary consultations, and detailed informed consent to assure full understanding of procedural risks, benefits, and complications. Currently, clinical recommendations rely on case reports, opinion, and usual practice (level 3 evidence). The strength of each recommendation provided in this report is categorized as level C. [ABSTRACT FROM AUTHOR]

Background: Probiotic bacterial supplementation has shown promising results in the treatment of periodontitis and the maintenance of periodontal health. The purpose of this investigation was to evaluate the influence of Lactobacillus reuteri or Bifidobacterium animalis subsp. lactis supplementation with and without prebiotic inulin on biofilm composition using an ex vivo biofilm model. Methods: Subgingival plaque specimens from three periodontitis‐affected human donors were used to grow biofilms on hydroxyapatite disks in media supplemented with varying combinations of prebiotic inulin, Lactobacillus reuteri, and Bifidobacterium animalis subsp. lactis. Relative abundances of bacterial genera present in mature biofilms were evaluated using 16S rRNA next‐generation sequencing. Diversity metrics of microbial communities were evaluated using a next‐generation microbiome bioinformatics platform. Results: Inulin supplementation produced statistically significant dose‐dependent increases in relative abundances of Lactobacillus and Bifidobacterium species (p < 0.001) with concomitant decreases in relative abundances of Streptococcus, Veillonella, Fusobacterium, Parvimonas, and Prevotella species (p < 0.001). Inoculation with L. reuteri or B. animalis subsp. lactis increased the relative abundance of only the supplemented probiotic genera (p < 0.05). Supplemental inulin led to a statistically significant decrease in biofilm alpha diversity (p < 0.001). Conclusions: The described ex vivo model appears suitable for investigating the effects of probiotic bacteria, prebiotic oligosaccharides, and combinations thereof on biofilm composition and complexity. Within the limitations imposed by this model, results from the present study underscore the potential for prebiotic inulin to modify biofilm composition favorably. Additional research further elucidating biologic rationale and controlled clinical research defining therapeutic benefits is warranted. [ABSTRACT FROM AUTHOR]

Purpose: Our purpose was to assess the frequency and impact of various site development procedures provided before, during, and after implant placement in an advanced dental education program. Methods: We evaluated all implant cases completed by two residents in each of three consecutive periodontics residency classes. Dependent variables included implant failure, complication occurrence, presence of radiographic bone loss, and need for tissue augmentation. We analyzed these outcomes against a panel of explanatory covariates. Results: Our study sample involved 370 site development procedures at 290 implant sites in 160 patients. Three factors exhibited statistically significant associations with need for tissue augmentation: alveolar ridge preservation (ARP) (odds ratio [OR] 0.28; 95% confidence interval [CI] 0.13, 0.57), immediate implant placement (IIP) (OR 0.21; 95% CI 0.10, 0.47), and implant submergence (OR 8.3; 95% CI 4.5, 15.3). Four factors predicted treatment complications: ARP (OR 6.1; 95% CI 1.3, 29.1), IIP (OR 6.1; 95% CI 1.06, 35.3), implant submergence (OR 5.3; 95% CI 1.1, 24.9), and mandibular arch (OR 31.3; 95% CI 1.9, 500). Anterior sites (OR 2.7; 95% CI 1.3, 5.8) were more likely to receive IIP. Conclusions: In the evaluated sample, implant placement at a site exhibiting a favorable volume of native bone was rare. Seventy‐eight percent of sites received hard tissue grafting during the treatment phase. The use of ARP or IIP at tooth extraction reduced subsequent tissue augmentation requirements. Education and training in ARP and other site development procedures may enhance the clinical practice and treatment outcomes of implant surgeons. [ABSTRACT FROM AUTHOR]

Introduction: Existing evidence supports superior treatment outcomes in guided bone regeneration (GBR) procedures employing membrane fixation. The purpose of this report is to present a specific flap design and suturing method for stabilizing GBR barrier membranes. Case Presentation: Two generally healthy patients received GBR using native collagen membranes stabilized with absorbable sutures. In both cases, we fixed barrier membranes apically using "triangle" sutures. Sling sutures (Case 1) or triangle sutures (Case 2) secured the crestal and palatal aspects of the membranes. No postoperative complications occurred, and both sites exhibited favorable alveolar ridge volume for implant placement. Conclusions: The described triangle suture technique reliably stabilized GBR barrier membranes without the need for fixation hardware. Compared with suturing methods that limit graft volume and apply pressure over the grafted area, the triangle suture may offer clinical advantages. [ABSTRACT FROM AUTHOR]

Focused Clinical Question: In generally healthy patients receiving third molar, periodontal, or dental implant surgery, do postoperative oral corticosteroids effectively limit pain and swelling compared with placebo or alternative medications? [ABSTRACT FROM AUTHOR]

Introduction: Schneiderian membrane perforation (SMP), which is usually readily manageable, is the most common intraoperative complication of sinus elevation surgery. Some evidence suggests that SMP is associated with increased risk for postoperative complications, including maxillary sinusitis. Antral wall discontinuity (AWD) is an acquired condition that may increase SMP likelihood and lead to larger, less‐manageable perforations. Case Presentation: A generally healthy patient receiving sinus elevation surgery exhibited an AWD in the palatine process of the maxilla. The osseous defect was isolated intraoperatively, and the Schneiderian membrane was sharply dissected from the palatal connective tissue. Favorable augmentation of the maxillary sinus was noted on cone‐beam computed tomography (CBCT) assessment at postoperative month 34. Conclusions: AWD (fusion of the Schneiderian membrane with the periosteum of the maxilla) is a condition identifiable on preoperative CBCT images, which may increase the incidence and severity of SMP during sinus elevation procedures. Careful assessment for integrity of antral osseous walls before surgery is essential. Presence of AWD may obligate modifications to the surgical plan, or in some cases, contraindicate sinus elevation surgery. [ABSTRACT FROM AUTHOR]

Introduction: Introduction of a surgical insult in conjunction with orthodontic therapy has been shown to accelerate treatment in minor tooth movement and comprehensive orthodontic cases by induction of the regional acceleratory phenomenon (RAP). When applying this concept to a molar tipped into an adjacent edentulous site, a dental implant can be planned to anchor the movement. Case Presentation: A generally and periodontally healthy 25‐year‐old patient presented missing tooth #19, with tooth #18 mesially tipped into the first molar crown space. A dental implant was placed in the #19 position. Following osseointegration, the implant anchored orthodontic movement of the adjacent tooth, which was initiated in conjunction with third molar extraction. Conclusion: Favorable biomechanics for molar uprighting can be achieved using an osseointegrated implant and a customized orthodontic device. The presented technique facilitates implant site development without delaying placement of the fixture and simplifies fabrication of a harmonious and anatomic implant‐supported restoration. Induction of the RAP may hasten treatment completion. [ABSTRACT FROM AUTHOR]

Introduction: Continuous and interrupted sling sutures (ISSs) are used around teeth in contemporary periodontics. However, conventional ISSs depend upon favorable tooth morphology for stability through the early healing period. The purpose of this report is to present a variation of the classic ISS that does not rely on favorable tooth morphology. Case Series: Tissue‐supported sling sutures (TSSs) were used for six patients undergoing root coverage, gingival augmentation, or pontic site development (guided bone regeneration) procedures. Conclusions: Although techniques such as vertical mattress suturing may support greater coronal flap advancement, the TSS technique does maintain coronal flap position while minimizing trauma to papillae. TSS stability is independent of tooth morphology and may offer clinicians flexibility in achieving reliable closure over hard and soft tissue implants. Like mattress sutures, TSSs reduce tension at the crestal incision line in tissue grafting procedures. [ABSTRACT FROM AUTHOR]

Focused Clinical Question: What factors identify the optimal surgical technique when a distal wedge procedure is indicated at a terminal maxillary or mandibular molar site? Summary: Incision design for the distal wedge procedure is based primarily on the dental arch (maxilla or mandible), the distance from the terminal molar to the hamular notch or ascending ramus, and the dimensions of the attached gingiva. Conclusions: In most situations, favorable clinical results are achievable irrespective of the chosen distal wedge method, and technique selection is based more on operator preference than evidence. However, anatomic limitations can render distal wedge procedures challenging in some cases, and procedural advantages of specific techniques can simplify treatment. One systematic approach to distal wedge technique selection is presented in this report. Additionally, a laser‐assisted distal wedge protocol is presented for cases in which unfavorable tooth‐to‐ramus distance or presence of a prominent external oblique ridge contraindicates conventional distal wedge techniques. [ABSTRACT FROM AUTHOR]

Focused Clinical Question: For a generally healthy patient with no risk indicators for postoperative infection, what is the most appropriate perioperative antibiotic regimen for sinus elevation surgery in terms of reducing postoperative infection risk and minimizing untoward effects? Clinical Scenario: A 38‐year‐old female patient in good general and periodontal health presents missing tooth #14 (Fig.). She reports no systemic conditions, no history of sinusitis, and no allergies. Medications include acetaminophen and ibuprofen as needed for pain. The patient's dentition is minimally restored, with no active caries. Cone‐beam computed tomography reveals a clear, pneumatized left maxillary sinus and inadequate bone volume to support dental implant placement (Fig.). No septa or pathologic lesions are present, the ostium appears patent, and no thickening of the Schneiderian membrane is appreciable. The patient states that she wants to replace her missing molar without restoring adjacent teeth (Figs. and). Baseline clinical appearance (example sinus elevation case). The patient is a healthy 38‐year‐old female missing tooth #14. Inadequate bone volume is present for dental implant placement due to pneumatization of the left maxillary sinus. Preoperative cone‐beam computed tomography images. 2a Sagittal view. 2b Coronal view. Cone‐beam computed tomography images at postoperative month 6. 3a Sagittal view. 3b Coronal view. Definitive implant‐supported restoration, tooth #14. [ABSTRACT FROM AUTHOR]

Introduction: Postoperative discomfort is a documented complication of the epithelialized palatal graft (EPG) procedure, and the expectation of an unpleasant patient experience may cause some practitioners to avoid EPG altogether. However, EPG affords distinct advantages in a variety of clinical situations, and the postoperative discomfort associated with the procedure can be minimized. Case Series: Three generally and periodontally healthy patients with gingival recession defects and minimal zones of attached gingiva received mandibular anterior EPG procedures. In all cases, collagen membranes were trimmed to fit the palatal donor sites and sutured in place. Two patients reported minimal donor site discomfort at any time point. One patient with large bilateral donor sites reported moderate palatal discomfort limited to the first postoperative week. All patients reported overall positive treatment experiences. Conclusions: Placement of a resorbable collagen membrane at large EPG harvest sites appears to limit topical irritation of the wound and may substantially improve patient comfort postoperatively. Combining local and systemic measures to minimize patient discomfort may render EPG procedures very tolerable for patients. Controlled clinical trials comparing patient‐centered outcomes following EPG harvest with and without collagen membrane placement appear warranted. [ABSTRACT FROM AUTHOR]

Introduction: The epithelialized palatal graft (EPG), introduced in 1963, has persisted as the gold standard for gingival augmentation, and in the present era, mucosal augmentation around dental implants has become an important concern. A limited body of evidence suggests peri‐implant mucosal augmentation may favorably impact bone and mucosal stability and peri‐implant health under some circumstances. Although more contemporary procedures for peri‐implant mucosal augmentation are often preferred based on convenience and esthetic considerations, EPG augmentation at dental implant sites is distinguishable from methods which do not deepen the vestibule and eliminate unfavorable superficial soft tissue. Implant sites augmented with EPG are qualitatively distinct from sites augmented using other methods. Case Series: Seven generally healthy patients received EPG augmentation before dental implant placement, at implant placement, before implant uncovering, or after implant uncovering. In each case, the patient exhibited a favorable zone of attached peri‐implant mucosa following treatment. Conclusions: Reliable mucosal augmentation with EPG is achievable at multiple phases in the course of dental implant therapy. EPG augmentation offers distinct clinical advantages and may be preferable to other mucosal augmentation strategies at some dental implant sites. [ABSTRACT FROM AUTHOR]

Introduction: Whether or not laser use provides any meaningful benefit at immediate implant and ridge preservation sites remains an open question in periodontics. However, various lasers have been used in conjunction with tooth extraction and immediate implant placement. Evidence supporting adjunctive laser irradiation at immediate implant and ridge preservation sites is mostly limited to preclinical studies and a small number of case reports. Case Series: Adjunctive neodymium‒doped: yttrium, aluminum, garnet (Nd:YAG) laser irradiation was used at six immediate implant sites and five ridge preservation sites. Three immediate implants were in maxillary incisor positions and three were in premolar positions, two maxillary and one mandibular. All cases exhibited favorable healing and satisfactory clinical outcomes. Conclusions: Nd:YAG laser energy application with 650‐µs pulse duration consistently supported rapid clot formation and graft containment at immediate implant and ridge preservation sites. Histologic analyses and controlled clinical trials comparing ridge preservation and immediate implant procedures with and without laser use are needed. Because cellular responses and clinical outcomes may be exquisitely sensitive to irradiation parameters, studies should report materials and methods in detail. [ABSTRACT FROM AUTHOR]

Background: Crestal bone thickness is a critical determinant of peri-implant tissue stability. This retrospective observational study sought to quantify the buccal bone thickness achieved adjacent to virtual dental implants following guided bone regeneration (GBR) surgery and evaluate the influence of patient- and procedure-related variables on buccal bone thickness.Methods: Cone-beam computed tomography (CBCT) images acquired from patients who had undergone GBR surgery between July 1, 2012, and November 7, 2016, were used for this analysis. In all cases, the GBR procedure involved a dense polytetrafluoroethylene (dPTFE) barrier membrane and a mineralized cortical particulate freeze-dried bone allograft (FDBA). Eighty-four virtual dental implants were placed at planned locations using CBCT images from 84 patients, and the adjacent buccal bone thickness was measured at each site. The effects of sex, age, estimated baseline ridge width, number of missing teeth in site, site type (tooth-bounded versus terminal position in arch), dental arch (mandibular or maxillary), arch location (anterior or posterior), smoking status, titanium reinforcement in the membrane, membrane fixation, and tenting screw use were assessed.Results: The mean post-GBR buccal bone thickness adjacent to virtual dental implants was 2.24 ± 1.01 mm. Fifty-nine of 84 virtual implants (70%) exhibited buccal bone thickness > 1.9 mm. GBR sites using membrane fixation produced significantly greater virtual implant buccal bone thickness than those without membrane fixation (2.31 ± 0.96 versus 1.15 ± 1.25 mm, P = 0.012). Virtual implant buccal bone thickness also exhibited moderate correlation with estimated initial ridge width (r = 0.43, P < 0.0001). The alveolar ridge at 81 virtual implant sites (96%) was classified as good or satisfactory, meaning dental implants were actually placed at these sites, with or without additional grafting at implant placement.Conclusions: Observations in this study suggest GBR procedures using dPTFE membranes and FDBA result in favorable ridge dimensions for dental implant placement in most cases. However, additional augmentation at implant surgery may be necessary at ≈ 30% of sites, if buccal bone thickness > 1.9 mm is intended. [ABSTRACT FROM AUTHOR]

Focused Clinical Question: How should clinicians manage dental extraction sockets when immediate implant placement is contraindicated, and alveolar ridge preservation is expected to result in inadequate bone volume for implant placement? Summary: Three fundamental options for extraction socket management form a hierarchical continuum in sites where dental implant placement is planned: place an immediate implant, perform ridge preservation, or perform ridge augmentation. The available volume and quality of bone and keratinized mucosa are the primary considerations driving the decision, and each tier in the continuum encompasses a variety of techniques with attendant advantages and disadvantages. Conclusions: Some immediate implant protocols require no mucoperiosteal flap and possibly produce the most favorable clinical and patient‐centered outcomes compared with other extraction socket management approaches. Conversely, guided bone regeneration at dental extraction sites can result in substantial gains in alveolar ridge dimensions, although this treatment may adversely influence mucosal architecture and carry increased risk of postoperative morbidity. When favorable bone and mucosa are present at a dental extraction site, immediate implant placement may be the treatment of choice, barring unusual circumstances. Ridge preservation, typically associated with minimal postoperative morbidity, is a rational second choice when acceptable ridge dimensions are anticipated after healing. [ABSTRACT FROM AUTHOR]

Introduction: The mandibular anterior can be a challenging anatomic location for achieving root coverage irrespective of the selected graft and surgical technique. The epithelialized palatal graft (EPG), often dismissed in deference to esthetic and patient‐centered considerations, is well‐suited for treating gingival recession in this region. Although a considerable volume of data exists assessing root coverage procedure outcomes, little evidence supports superiority of any one technique specifically applied to the mandibular anterior. Case Presentation: Two periodontally and systemically healthy patients with multiple adjacent Class I and III recession defects in the mandibular anterior were treated with EPG. Recipient site dimensions in one case obligated bilateral palatal donor sites. In this case, the two autogenous grafts were carefully sutured extraorally before placement. Favorable increases in attached gingival dimensions and partial or complete root coverage were noted after 12‐ or 18‐month follow‐up periods. In the case requiring bilateral donor sites, no transition between the two grafts could be appreciated after healing. Conclusions: Overall, subepithelial connective tissue graft (SCTG)‐based techniques reportedly produce higher mean root coverage percentages and more frequent complete root coverage compared with EPG. However, when observations are limited to the mandibular anterior, there are insufficient data to conclude SCTG is superior to EPG. In the presented cases, EPG at multiple adjacent mandibular anterior recession defects produced favorable clinical outcomes. Extraoral suturing of bilaterally harvested grafts facilitated graft stabilization and minimized irregularities in gingival architecture after healing. [ABSTRACT FROM AUTHOR]

Introduction: Patient‐, site‐, and procedure‐related factors important for successful periodontal regeneration have been defined in the periodontics literature by insightful clinician‐researchers. Prevention of bacterial contamination of the surgical site through careful wound closure and meticulous postoperative care is a critical procedure‐related factor necessary for periodontal regeneration. Dense polytetrafluoroethylene (dPTFE) is a nonresorbable barrier material that may protect bone replacement grafts (BRG) against bacterial contamination for a short period during early wound healing if membrane exposure occurs. Case Presentation: A 35‐year‐old African American female with a deep/narrow infrabony periodontal defect and Hamp degree I furcation involvement at tooth #14 (mesial) underwent combination BRG/guided tissue regeneration (GTR) using a mineralized/demineralized freeze‐dried bone allograft and a dPTFE barrier membrane. Favorable clinical and radiographic outcomes were noted nine months following the procedure. Conclusions: Two reports evaluating clinical parameters following use of dPTFE membranes for GTR appear in the literature. The present case provides clinical and radiographic outcome assessments following combination BRG/GTR using a dPTFE membrane. This material may be of interest for periodontal regeneration due to an ability to temporarily limit bacterial influence if membrane exposure occurs. [ABSTRACT FROM AUTHOR]

Introduction: Sinus graft infection with consequent acute bacterial rhinosinusitis (ABRS) is a complication that can occur during the postoperative period following sinus augmentation surgery. A small group of bacteria appear to predominate in ABRS, and these bacteria are empirically susceptible to tetracycline antibiotics, barring the presence of resistant strains. Historically, clinicians have mixed tetracycline with various biomaterials or hydrated biomaterials in a dilute tetracycline solution in the treatment of periodontal disease and for ridge preservation/augmentation indications. Case Presentation: In the present case, a 39‐year‐old African‐American male with sinus graft infection and signs and symptoms consistent with ABRS was successfully treated by removing the initial graft material, thoroughly debriding and irrigating the antrum, and placing a freeze‐dried bone allograft hydrated in an aqueous tetracycline solution. Conclusion: Given the typical bacteria present in ABRS, locally applied tetracycline may be useful prophylactically in sinus elevation surgery or as an adjunct in managing postoperative sinus graft infection. [ABSTRACT FROM AUTHOR]

Introduction: Minimally invasive surgical techniques in periodontics, including methods for ridge augmentation, have been shown to achieve surgical goals while minimizing swelling, decreasing postoperative discomfort, and enhancing soft tissue architecture. The present case illustrates a minimally invasive guided bone regeneration technique for augmentation of a deficient alveolar ridge in the esthetic zone. Case Presentation: A 30‐year‐old patient received localized ridge augmentation utilizing tunnel access for guided bone regeneration with a dense polytetrafluoroethylene membrane and a freeze‐dried bone allograft. The patient experienced minimal postoperative swelling and discomfort, and the procedure resulted in favorable ridge dimensions for implant placement. Conclusions: The tunnel access for guided bone regeneration presented in this case may offer advantages similar to other minimally invasive ridge augmentation techniques. Further controlled clinical study is warranted. [ABSTRACT FROM AUTHOR]

Introduction: Numerous biomaterials are available for augmenting bone around dental implants. In contained extraction sockets, a demineralized freeze‐dried bone allograft (DFDBA) appears capable of maintaining dimensional stability of the alveolar ridge as well as mineralized alternatives but may yield a higher percentage of new vital bone. When DFDBA is used in large horizontal gap defects at molar immediate implant sites, graft containment and protection must occur through provisional restoration, an anatomic custom healing abutment, or by other means. Case Series: Two mandibular molar immediate implant sites received DFDBA covered by dense polytetrafluoroethylene membranes. Conclusion: The present report suggests a protocol for maintaining favorable dimensional stability of the alveolar ridge at molar immediate implant sites, while possibly minimizing residual peri‐implant biomaterial. [ABSTRACT FROM AUTHOR]

Introduction: A contemporary protocol for managing horizontal alveolar defects adjacent to immediate implants includes placement of a well‐designed provisional restoration to contain graft material and seal the socket. However, immediate provisionalization is not always possible or practical. Case Presentation: A 39‐year‐old male presented with a non‐restorable tooth #29, which was extracted. An immediate implant was placed in the tooth #29 position, and a freeze‐dried bone allograft was placed in the horizontal defect between the implant platform and osseous walls. A neodymium:yttrium‐aluminum‐garnet (Nd:YAG) laser was used to create a stable fibrin clot over the graft material. After 31 months, favorable radiographic bone levels and complete papilla fill were noted. Conclusion: The present case illustrates use of an Nd:YAG laser in the management of an immediate implant horizontal defect in lieu of an immediate provisional restoration. [ABSTRACT FROM AUTHOR]

Type of Case: A 32‐year‐old female presents missing tooth #5 and requesting replacement with a dental implant. She has an unremarkable medical history. The tooth #5 site is a healed ridge with adequate bone to support an implant without additional augmentation. Clinical Approach #1 (CMR and TMJ): This approach involves routine implant surgery with placement of a healing abutment. Preoperative management includes 2 g amoxicillin 1 hour prior to the procedure and postoperative pain medication. The rationale for use of an antibiotic is to decrease the risk of infection and implant failure and to reduce peri‐implant inflammation during early healing. The desired effect of the antibiotic is to minimize or eliminate the negative effects of bacteria in the wound site and on the implant surface during healing. This clinical approach is recommended to protect the investment of resources and time by the patient and dental team for optimal treatment outcomes. Clinical Approach #2 (AWB, BGC, and KJE): This approach involves routine implant surgery with placement of a healing abutment. Postoperative management includes pain medications without antibiotic use. The rationale for avoidance of antibiotics is to eliminate risk of an adverse drug reaction such as urticaria, anaphylaxis, or gastrointestinal disturbances. Because the evidence justifying antibiotic coverage is considered to be weak, clinicians are advised to consider withholding antibiotic prescriptions for routine implant placement as a means of risk mitigation for the patient and public health in general. [ABSTRACT FROM AUTHOR]

In recent years, evidence-based dentistry has become the ideal for research, academia, and clinical practice. However, barriers to implementation are many, including the complexity of interpreting conflicting evidence as well as difficulties in accessing it. Furthermore, many proponents of evidence-based care seem to assume that good evidence consistently exists and that clinicians can and will objectively evaluate data so as to apply the best evidence to individual patients' needs. The authors argue that these shortcomings may mislead many clinicians and that students should be adequately prepared to cope with some of the more complex issues surrounding evidence-based practice. Cognitive biases and heuristics shape every aspect of our lives, including our professional behavior. This article reviews literature from medicine, psychology, and behavioral economics to explore the barriers to implementing evidence-based dentistry. Internal factors include biases that affect clinical decision making: hindsight bias, optimism bias, survivor bias, and blind-spot bias. External factors include publication bias, corporate bias, and lack of transparency that may skew the available evidence in the peer-reviewed literature. Raising awareness of how these biases exert subtle influence on decision making and patient care can lead to a more nuanced discussion of addressing and overcoming barriers to evidence-based practice. [ABSTRACT FROM AUTHOR]

A combination of sequential extraction with stable isotope ratio measurements of Se might offer new insights into biogeochemical processes governing Se turnover in soils. Therefore, we determined the Se partitioning among three operationally defined sequential extracts (0.1 mol L-1 K2HPO4-KH2PO4 at pH 7,0.05 mol L-1 NaOH, cone. HNO3) and the stable isotope ratios of total Se (δ82/76Se values) in 10 topsoils under 5 different land uses (alluvial grasslands, forests, house gardens, parks, and roadside grassland) from the city of Bayreuth (ca. 73,000 inhabitants) in Germany. Furthermore, we determined S and Due to image rights restrictions, multiple line equation(s) cannot be graphically displayed. concentrations and stable isotope ratios of total S (δ34S values) to support our interpretation of the Se concentrations and isotope ratios because of the chemical similarity of Se and S. All topsoils had low total Se concentrations (0.09-0.52 mgkg-1). The largest contribution to total Se was extracted with NaOH comprising up to 42%,which is thought to be associated with organic matter and metal oxides. The (δ82/76Se values)Se values of total Se in the topsoils were dose to the bulk Earth composition with an average S Se value of-0.03 ± SD 0.38‰ suggesting that there was no or little Se isotope fractionation in soil. We attribute the small isotope fractionation to the low bioavailability of Se as a consequence of the presence of Fe oxides (adsorbing the dominating Se(IV) forms strongly), organic matter, and Due to image rights restrictions, multiple line equation(s) cannot be graphically displayed. (prevents biouptake of the Se(IV) forms) in the study soils. Small Se isotope fractionations of -0.59 to -0.35‰ in mainly forest soils and of 0.26 to 0.45‰ in mainly alluvial soils were presumably caused by soil/plant-recycling and Se contamination by river water, respectively. In spite of the similarities in the assimilation of S and Se by organisms, the total S and Se isotope ratios in soil were not correlated. Our results demonstrate that Se in urban soils developed from Se-poor substrates is minimally cycled through the biosphere likely because of low bioavailability and competition with Due to image rights restrictions, multiple line equation(s) cannot be graphically displayed. [ABSTRACT FROM AUTHOR]

The article presents a study which investigates the selenium stable isotope during selenium biogeochemical cycling that can be found in a lacustrine environment in Sweitzer Lake, Colorado. It stresses the importance of selenium reduction in the sediments found in the lake and its isotopic impact between surface waters and reduction sites within the sediments. Moreover, the study concludes that potential isotopes for selenium are considered as migration indicators that are found in fish tissues and phytoplankton.

Surveys were sent to Harvard School of Dental Medicine students and graduates from the classes of 2000 through 2006 to determine their current primary means of achieving mandibular anesthesia. Orthodontists and orthodontic residents were excluded. All subjects received clinical training in the conventional inferior alveolar nerve block and two alternative techniques (the Akinosi mandibular block and the Gow-Gates mandibular block) during their predoctoral dental education. This study tests the hypothesis that students and graduates who received training in the conventional inferior alveolar nerve block, the Akinosi mandibular block, and the Gow-Gates mandibular block will report more frequent current utilization of alternatives to the conventional inferior alveolar nerve block than clinicians trained in the conventional technique only. At the 95 percent confidence level, we estimated that between 3.7 percent and 16.1 percent (mean=8.5 percent) of clinicians trained in using the Gow-Gates technique use this injection technique primarily, and between 35.4 percent and 56.3 percent (mean=47.5 percent) of those trained in the Gow-Gates method never use this technique. At the same confidence level, between 0.0 percent and 3.8 percent (mean=0.0 percent) of clinicians trained in using the Akinosi technique use this injection clinical technique primarily, and between 62.2 percent and 81.1 percent (mean=72.3 percent) of those trained in the Akinosi method never use this technique. No control group that was completely untrained in the Gow-Gates or Akinosi techniques was available for comparison. However, we presume that zero percent of clinicians who have not been trained in a given technique will use the technique in clinical practice. The confidence interval for the Gow-Gates method excludes this value, while the confidence interval for the Akinosi technique includes zero percent. We conclude that, in the study population, formal clinical training in the Gow-Gates and Akinosi injection techniques lead to a small but significant increase in current primary utilization of the Gow-Gates technique. No significant increase in current primary utilization of the Akinosi technique was found. [ABSTRACT FROM AUTHOR]

This article discusses the amount of nitrogen which is contributed to ground water from tile-drained corn belt watersheds with fine grained soil in central Illinois. The authors argue that a significant amount of nitrogen reached shallow ground water by transportation past the tile drains. The results also showed that significant levels of nitrogen were added to groundwater by denitrifying bacteria found at depth throughout the watershed. Laboratory tests showed that a nitrate could be rapidly denitrified. They conclude that fine grained soils may act as a significant nitrogen sink in groundwater compared to surface water.

Selenium stable isotope ratios are known to shift in predictable ways during various microbial, chemical, and biological processes, and can be used to better understand Se cycling in contaminated environments. In this study we used Se stable isotopes to discern the mechanisms controlling the transformation of oxidized, aqueous forms of Se to reduced, insoluble forms in sediments of Se‐affected environments. We measured 80Se/76Se in surface waters, shallow ground waters, evaporites, digested plants and sediments, and sequential extracts from several sites where agricultural drainage water is processed in the San Joaquin Valley of California. Selenium isotope analyses of samples obtained from the Tulare Lake Drainage District flow‐through wetland reveal small isotopic contrasts (mean difference 0.7‰) between surface water and reduced Se species in the underlying sediments. Selenium in aquatic macrophytes was very similar isotopically to the NaOH and Na2SO3 sediment extracts designed to recover soluble organic Se and Se(0), respectively. For the integrated on‐farm drainage management sites, evaporite salts were slightly (approximately 0.6‰) enriched in the heavier isotope relative to the inferred parent waters, whereas surface soils were slightly (approximately 1.4‰) depleted. Bacterial or chemical reduction of Se(VI) or Se(IV) may be occurring at these sites, but the small isotopic contrasts suggest that other, less isotopically fractionating mechanisms are responsible for accumulation of reduced forms in the sediments. These findings provide evidence that Se assimilation by plants and algae followed by deposition and mineralization is the dominant transformation pathway responsible for accumulation of reduced forms of Se in the wetland sediments. [ABSTRACT FROM AUTHOR]

We use reactive transport modeling to consider how diffusion and hydrodynamic dispersion, cross-formational flow, and subsurface production affect the steady state distribution in flow regimes of the radioactive isotope 36Cl, and the relationship of the isotope distribution to groundwater residence time, or 'age.' The isotope forms naturally in the atmosphere, dissolves in rainwater, and then decays in the subsurface with a half-life of ∼301,000 years; hence it is important for age dating very old groundwater. In a simple flow regime composed of an aquifer confined above and below by aquitards, isotopic age may correspond rather well with a groundwater's 'piston flow' age. This correspondence is favored where the aquifer is thick, cross-formational flow is insignificant, salinity is low, and the diffusion coefficient within the aquitards is small. The maximum dateable age, however, is somewhat smaller than expected from the isotope's half-life. Owing to the effect of 'dead' chloride, dating based on isotope abundance (the 36Cl/Cl ratio) may be less accurate than that based on 36Cl concentration. Cross-formational flow can strongly affect the 36Cl distribution and abundance, preventing the rates and even direction of flow within an aquifer from being interpreted using the piston flow model. Where salinity is moderate or high, the isotope distribution is controlled by subsurface production, and dating on the basis of the decay of atmospheric 36Cl is not possible. In models of simple flow regimes the 36Cl method fails to predict groundwater age accurately where groundwater chlorinity exceeds ∼75-150 mg kg−1. Reactive transport models hold considerable promise for improving interpretation of the rates and patterns of groundwater flow from radioisotope distributions. [ABSTRACT FROM AUTHOR]

Sr isotope ratios were measured in groundwater, whole rock digestions, and cation exchange extracts from a clay-rich groundwater system at Ernest O. Lawrence Berkeley National Laboratory and were used to constrain flow velocities and search for preferential flow paths. In the Orinda formation siltstone, 87Sr/86Sr increases strongly over tens of meters along presumed flow paths, indicating slow groundwater flow. Dissolved Sr is close to isotopic equilibrium with the exchangeable Sr in the clays, and the observed 87Sr/86Sr increase is interpreted as a cation exchange front moving slowly through the unit combined with dissolution of minerals with relatively high 87Sr/86Sr ratios. The data are inverted using a one-dimensional transport-dissolution-exchange model; the results indicate long-term average flow velocities of less than 0.2 m/yr which are consistent with 14C measurements. The data suggest a lack of strong preferential flow paths through this unit. [ABSTRACT FROM AUTHOR]

A transport-reaction model calculates isotope ratios (e.g., 87Sr/86Sr) in groundwater systems where isotope ratios in the fluid are affected by two distinct types of water-rock interaction: rapid exchange reactions and slower dissolution reactions. Rapid exchange reactions buffer the groundwater isotope ratios, and a two-stage evolution is observed. After a perturbation in the system an exchange front, which can be described by a retardation equation, propagates through the system at a velocity equal to the groundwater velocity divided by a retardation factor. If steady boundary conditions are maintained, the exchange front is advected out of the system and a quasi-steady state develops in which dissolution reactions influence the isotope ratios but the exchange reactions have no effect. Because clay minerals which readily exchange ions or water molecules with groundwater are found in most hydrologic systems, exchange reactions may significantly affect interpretation of isotopic data. [ABSTRACT FROM AUTHOR]

A model enabling extraction of hydrologic information from spatial and temporal patterns in measurements of isotope ratios in water-rock systems is presented. The model describes the evolution of isotope ratios in response to solute transport and water-rock interaction. In advective systems, a single dimensionless parameter (a Damköhler number, N D) dominates in determining the distance over which isotopic equilibrium between the water and rock is approached. Some isotope ratios act as conservative tracers ( N D ≪ 1), while others reflect only interaction with the local host rock ( N D ≫ 1). If N D is close to one (i.e., the distance for equilibration is close to the length scale of observation), isotope ratio measurements can be used to determine N D, which in turn may yield information concerning reaction rates, or spatial variations in water velocity. Zones of high velocity (e.g., as a result of greater fracture density), or less reactive zones, may be identified through observation of their lower N D values. The model is applied to paleohydrologic interpretations of Sr isotope data from calcite fracture fillings in drill cores from Yucca Mountain, Nevada (Marshall et al., 1992). The results agree with other studies suggesting 'fast path' transport in the unsaturated zone. Also, we find that the data do not give a conclusive indication of paleowater table elevation because of the effects of water-rock interaction. [ABSTRACT FROM AUTHOR]

Presents a commentary on ground water age concept. Definition of ground water age; Application of piston flow model; Techniques for estimating the age of ground water from its composition.

Background Methods and Results Conclusions Key points Current evidence acknowledges guided bone regeneration (GBR) as a predictable therapeutic modality in the augmentation of a deficient alveolar ridge. Such deficiencies often reveal inadequate bone volume to support implant placement in a position amenable to prosthetic reconstruction. Additionally, an evolving body of literature demonstrates that membrane fixation may lead to improved clinical bone gain through positively influencing blood clot formation, stability, and the eventual osteogenic potential of the defect. Alternative benefits to membrane fixation, such as reduced graft displacement and reduction in wound micromotion, have also been cited as mechanisms for an increased regenerative response.The aim of this report was to present a case, including diagnosis, treatment, and follow‐up for the reconstruction of a horizontal ridge deficiency. The patient's deficiency in ridge volume was found to be a developmental sequelae of lateral incisor agenesis, resulting in an underdeveloped midfacial region of the alveolar process subjacent to sites #7 and #10. The fixation protocol outlined in this report demonstrated adequate horizontal ridge augmentation to facilitate future prosthetic reconstruction with the use of implants.Numerous protocols have been established in an attempt to achieve effective barrier membrane stabilization for bone augmentation procedures. However, some techniques are poorly suited for the anatomically challenging region of the anterior maxilla. A case report describing the utilization of the anterior nasal spine for anchorage of a membrane‐stabilizing suture may present a novel, safe, and effective technique for stabilizing the intended region of augmentation, as well as preventing graft migration beyond the membrane–maxilla interface. Regarding guided bone regeneration (GBR) procedures, micromotion of the membrane or of the underlying particulate graft may negatively influence the volume of the augmented site. The ability to adequately stabilize the graft–membrane interface is recognized as a necessary prerequisite to predictably achieve optimal surgical outcomes. To the authors’ knowledge, there is no clinical or scientific evidence regarding the use of the anterior nasal spine for membrane anchorage in maxillary GBR procedures, and thus a novel approach to membrane stabilization is introduced. Regarding guided bone regeneration (GBR) procedures, micromotion of the membrane or of the underlying particulate graft may negatively influence the volume of the augmented site.The ability to adequately stabilize the graft–membrane interface is recognized as a necessary prerequisite to predictably achieve optimal surgical outcomes.To the authors’ knowledge, there is no clinical or scientific evidence regarding the use of the anterior nasal spine for membrane anchorage in maxillary GBR procedures, and thus a novel approach to membrane stabilization is introduced. [ABSTRACT FROM AUTHOR]