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Purpose: Preoperative identification of the intraosseous posterior superior alveolar artery (PSAA) is critical when planning sinus surgery. This study was conducted to determine the distance between the cementoenamel junction and the PSAA, as well as to identify factors influencing the detection of the PSAA on cone-beam computed tomography (CBCT). Materials and Methods: In total, 254 CBCT scans of maxillary sinuses, acquired with 2 different scanners, were examined to identify the PSAA. The distance from the cementoenamel junction (CEJ) to the PSAA was recorded at each maxillary posterior tooth position. Binomial logistic regression and multiple linear regression were employed to evaluate the effects of scanner type, CBCT parameters, sex, and age on PSAA detection and CEJ-PSAA distance, respectively. P-values less than 0.05 were considered to indicate statistical significance. Results: The mean CEJ-PSAA distances at the second molar, first molar, second premolar, and first premolar positions were 17.0±4.0 mm, 21.8±4.1 mm, 19.5±4.7 mm, and 19.9±4.9 mm for scanner 1, respectively, and 17.3±3.5 mm, 16.9±4.3 mm, 18.5±4.1 mm, and 18.4±4.3 mm for scanner 2. No independent variable significantly influenced PSAA detection. However, tooth position (b= -0.67, P<0.05) and scanner type (b= -1.3, P<0.05) were significant predictors of CEJ-PSAA distance. Conclusion: CBCT-based estimates of CEJ-PSAA distance were comparable to those obtained in previous studies involving cadavers, CT, and CBCT. The type of CBCT scanner may slightly influence this measurement. No independent variable significantly impacted PSAA detection. [ABSTRACT FROM AUTHOR]

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]

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: 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]

CHARGE syndrome is a multiple anomaly disorder in which patients present with a variety of phenotypes, including ocular coloboma, heart defects, choanal atresia, retarded growth and development, genitourinary hypoplasia and earabnormalities (1). Despite 70-90% of CHARGE syndrome cases resulting from mutations in the gene CHD7, which encodes an ATP-dependent chromatin remodeller, the pathways underlying the diverse phenotypes remain poorly understood (2). Surprisingly, our studies of a knock-in mutant mouse strain that expresses a stabilized and transcriptionally dead variant of the tumour-suppressor protein p53 (p[53.sup.25,26,53,54]) (3), along with a wild-type allele of p53 (also known as Trp53), revealed late-gestational embryonic lethality associated with a host of phenotypes that are characteristic of CHARGE syndrome, including coloboma, inner and outer ear malformations, heart outflow tract defects and craniofacial defects. We found that the p[53.sup.25,26,53,54/-] mutant protein stabilized and hyperactivated wild-type p53, which then inappropriately induced its target genes and triggered cell-cycle arrest or apoptosis during development. Importantly, these phenotypes were only observed with a wild-type p53 allele, as p[53.sup.25,26,53,54/-] embryos were fully viable. Furthermore, we found that CHD7 can bind to the p53promoter, thereby negatively regulating p53 expression, and that CHD7 loss in mouse neural crest cells or samples from patients with CHARGE syndrome results in p53 activation. Strikingly, we found that p53 heterozygosity partially rescued the phenotypes in Chd7-null mouse embryos, demonstrating that p53 contributes to the phenotypes that result from CHD7 loss. Thus, inappropriate p53 activation during development can promote CHARGE phenotypes, supporting the idea that p53 has a critical role in developmental syndromes and providing important insight into the mechanisms underlying CHARGE syndrome., Unrestrained p53 activity induced by loss of the negative regulators MDM2 or MDM4 causes early embryonic lethality (4). To explore the role of transcriptional activation by p53 in promoting developmental [...]

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]

The article reports that In November 2019, a 68-year-old woman with no significant medical history came to the Department of Periodontics of the Army Postgraduate Dental School in Fort Gordon, GA, complaining of difficulty in chewing and dissatisfaction with her smile. Examination revealed an edentulous maxilla and missing teeth nos. 17 through 19, 21, and 28 through 31.

The ability to measure [sup.238]U/[sup.235]U to high precision presents an important new opportunity to study the fate and transport of uranium in the environment. The ratio of [sup.238]U/[sup.235]U was determined by multicollector--inductively coupled plasma--mass spectrometer in six uranium ore samples representing two different classes of deposits. Significant offsets in [sup.238]U/[sup.235]U are observed between uranium ores precipitated from groundwaters at low temperature versus hydrothermal deposits precipitated at high temperatures, reinforcing an observation made previously but lacking the needed precision. Specifically, tabular sandstone-type uranium deposits were found to be depleted in [sup.235]U, with a total offset between low-temperature deposits and higher temperature deposits of [approximately equal to] 1.0 [per thousand]. We attribute this offset to reflect a temperature-dependent fractionation related to the nuclear field shift effect during chemical reduction of uranium in ambient temperature groundwaters.

Objective: The purpose of this report was to document clinical responses to Nd:YAG laser energy in patients with surgical injury to terminal branches of the trigeminal nerve. Background: Limited evidence from in vitro, animal, and human studies suggests infrared laser energy may positively influence recovery after peripheral or cranial nerve injury, although clinical effects of neodymiumdoped yttrium aluminum garnet (Nd:YAG) lasers remain unstudied in this context. Methods: We applied Nd:YAG laser energy in the treatment of three consecutive patients presenting with altered neurosensory function following various oral and maxillofacial procedures. The time interval between surgical injury and laser photobiomodulation ranged from one week to two years. Results: All patients exhibited reduction in the area of diminished sensation and partial recovery of normal neurosensory function. The two patients with long-standing neurosensory deficiency experienced near complete recovery of intraoral sensation, with residual zones of diminished sensation from the perioral skin. Conclusions: Although all patients in this case series demonstrated clinical improvements compared with baseline, controlled studies are needed to determine whether Nd:YAG laser energy accelerates or enhances recovery of neurosensory function after surgical nerve injury. Studies establishing the relative efficacies of Nd:YAG and diode lasers appear warranted. [ABSTRACT FROM AUTHOR]

Groundwater in aquifers is generally older than expected on the basis of flow velocity, and this observation has important implications for interpreting radiometric age determinations. Hydrologists commonly account for the aging of water as it flows along streamtubes, but not for the effects of mixing old water from aquitards (or confining layers) into aquifers, because the rate of mass exchange between aquifers and aquitards can in many cases be assumed to be small. We show, however, that the effect on age of such mixing does not depend on the mixing rate; this is the paradox of groundwater age. Surprisingly, the contribution of aquitards to the age of groundwater in aquifers depends only on the ratio of fluid volume in aquitards to aquifers. This result has broad importance for understanding the relationship between groundwater flow and the distribution of radiometric age. Keywords: groundwater age, residence time, radiometric age dating.

Researchers from the Lawrence Berkeley National Laboratory, U.S. Geological Survey and University of Illinois studied ratios of selenium stable isotopes found from samples taken at the San Francisco Bay Estuary to investigate the dynamics and anthropogenic inputs of selenium.

Introduction: Guided bone regeneration (GBR) is the most commonly utilized procedure for augmenting deficient alveolar ridges in support of dental implant placement. In a GBR procedure, barrier membrane dimensions, bone graft volume, and surgical complexity may influence the risk of postsurgical morbidity. Case presentation: A 25-year-old female in good general health received GBR at two mandibular first molar sites exhibiting horizontal ridge deficiency. High-density polytetrafluoroethylene membranes were intentionally limited in size, and small-volume freeze-dried bone allografts were applied only where clinically beneficial for implant site development. Treatment resulted in clinically favorable ridge augmentation with no appreciable swelling and minimal postoperative discomfort. Conclusion: At dental implant sites exhibiting modest alveolar ridge deficiency, limiting GBR barrier membrane dimensions and bone graft volumes may enhance patient-centered outcomes while accomplishing clinical goals. [ABSTRACT FROM AUTHOR]

Objective: The objective of this study was to illustrate the efficacy of a novel imaging analysis technology to capture horizontal and vertical dimensional changes following horizontal alveolar ridge augmentation (HRA). Methods: Cone-beam computed tomography (CBCT) volumes from 65 HRA sites in 57 patients were available for evaluation, employing a three-dimensional analysis software to overlay preoperative and post-augmentation CBCT volumes. Horizontal and vertical alveolar ridge dimensional (HRD/VRD) changes were recorded considering a panel of patient-, site-, and procedure-related explanatory variables. Results: VRD changes ranged from -2.9 to 3.0 mm, more than half anterior sites losing alveolar ridge height. Mean HRD increase at the 3- and 5-mm levels apical to the alveolar crest amounted to 2.3±1.6 and 2.4±1.3 mm, respectively, membrane fixation and non-resorbable membrane use associated with significantly greater gains. Conclusions: To date, studies reporting dimensional changes following HRA predominantly rely on serial in situ orofacial caliper recordings omitting vertical alterations. The protocol employed in this study allows simultaneous HRD and VRD evaluations and assures baseline and post-augmentation recordings are made at the same alveolar ridge position. Compared with in situ recording, CBCT overlay analysis may achieve a more complete characterization of dimensional changes following HRA. [ABSTRACT FROM AUTHOR]

A considerable percentage of dental implant patients experience biofilm-mediated peri-implant disease following transmucosal abutment application. Bacterial adhesion is an early step in biofilm development. Our purpose was to assess adhesion of specific bacterial species to titanium over short exposure periods. Eight bacterial species were selected for this analysis: Streptococcus oralis, Streptococcus mitis, Gemella haemolysans, Streptococcus gordonii, Streptococcus sanguinis, Neisseria flavescens, Streptococcus salivarius, and Pseudomonas aeruginosa. We cultured each species with appropriate media and exposed titanium foil discs to the bacteria for 60, 15, 5, 1, or 0.25 minutes. Optical density at 600-nm wavelength (OD600) was assessed for the baseline inoculum and each species/exposure combination. The proportion of bacteria adherent to titanium was determined for each experimental condition. Striking titanium adhesion was noted for all evaluated species even when exposure time was limited to 15 seconds. Strategies to limit bacterial adhesion at dental implant surfaces may offer potential for improved treatment outcomes and preservation of peri-implant health. [ABSTRACT FROM AUTHOR]

Introduction: Retained cement following delivery of an implant-supported crown is strongly associated with peri-implant mucositis and peri-implantitis, and screw retention is a strategy for avoiding this problem entirely. In the esthetic zone, screw retention compromises esthetics unless the screw access in the crown is concealed to the palatal of the incisal edge. To avoid positioning the implant platform excessively toward the palate, practitioners can design an angled screw access channel in the crown. Case Presentation: A healthy 22-year-old patient with nonrestorable tooth #9 received extraction and immediate implant placement with immediate provisionalization. The screw access channel for the provisional restoration involved the incisal edge. Rather than placing a custom abutment and cementing the definitive restoration, an angled screw access channel was employed. The implant-supported restoration exhibited favorable esthetics, and the possibility of retained cement was avoided. Conclusion: Up to a point, positioning maxillary anterior implants toward the palate is favorable. When the long axis of the implant is directed between the incisal edge and the cingulum of adjacent teeth, the implantsupported crown can be screw retained without compromising esthetics. In immediate implant situations, such positioning also increases the distance between the implant and the facial alveolar bone and encourages a favorable position of the marginal peri-implant mucosa. However, an excessively palatal platform position compels a restoration with irregular contours, which can frustrate proper oral hygiene and professional maintenance. Angled screw access channels allow screw retention without excessive palatal positioning of the platform, avoiding the possibility of cement-related peri-implant disease. [ABSTRACT FROM AUTHOR]

Objective: To assess stability of laser periodontal therapy (LPT) results after orthodontic tooth movement. Background: Periodontitis and malocclusion each exhibit high global prevalence. Thus, dentists inevitably face increasing demand for orthodontic treatment in patients with reduced periodontal support. Many of these patients benefit from orthodontic treatment, provided that periodontal inflammation is controlled. Materials and methods: We present a case demonstrating successful orthodontic treatment of periodontally compromised teeth after LPT. A patient with severe attachment and alveolar bone loss received orthodontic treatment 13 months after neodymium-doped: yttrium aluminum garnet LPT (1064 nm). We utilized three laser parameter sets for various purposes during the procedure--ablation of the periodontal pocket epithelium (2.8 W, 20 Hz, 100 ls), clot stabilization (2.8 W, 20 Hz, 550 ls), and photobiomodulation (2.8 W, 20 Hz, 100 ls, noncontact). Results: Treatment resulted in improved radiographic bone levels, clinical parameters consistent with periodontal health, and favorable occlusal relationships. Conclusions: In the presented case, we successfully treated a patient presenting with malocclusion and reduced periodontal support while avoiding the risk and morbidity of conventional periodontal surgery. Controlled clinical research to establish the predictability of the described approach appears warranted. [ABSTRACT FROM AUTHOR]