Use of ultrasound imaging for assessment of the periodontium: A systematic review.

The objective of this study was to systematically review the literature regarding diagnostic applications of ultrasound imaging for evaluation of the periodontium in humans. The search was conducted on Medline, EMBASE, Web of Science, Scopus, Cochrane, and PubMed up to April 3, 2023. The studies included were exclusively human studies that assessed the periodontium with ultrasound (US) imaging (b-mode). Outcomes measured included alveolar bone level, alveolar bone thickness, gingival thickness, and blood flow quantification. References were imported to Covidence. Two reviewers conducted phases 1 and 2. The JBI risk assessment tool for cross-sectional studies was used. Extracted data included the transducer and measurements used and the study's outcomes. The search yielded 4892 studies after removing duplicates. From these, 25 studies were included and selected for extraction. Included studies retrieved outcomes from US examinations of the periodontal tissues. From the selected studies, 15 used US on natural teeth, 4 used US on implants, 2 used US on edentulous ridges, and 4 used color flow/power in US to evaluate the blood flow. The results of the present systematic review suggest that US might be a feasible and valuable diagnostic tool for the periodontium, with the potential to complement shortfalls of current radiographic technologies.

The repeatability of periodontal imaging with intraoral ultrasound scanning.

OBJECTIVE: Ultrasound is a non-invasive and low-cost diagnostic tool widely used in medicine. Recent studies have demonstrated that ultrasound imaging might have the potential to be used intraorally to assess the periodontium by comparing it to current imaging methods. This study aims to characterize the repeatability of intraoral periodontal ultrasound imaging. MATERIALS AND METHODS: Two hundred and twenty-three teeth were scanned from fourteen volunteers participating in this study. One operator conducted all the scans in each tooth thrice with a 20 MHz intraoral ultrasound. The repeatability of three measurements, alveolar bone crest to the cementoenamel junction (ABC-CEJ), gingival thickness (GT), and alveolar bone thickness (ABT), was calculated with intercorrelation coefficient (ICC). Measurements were also compared with mean absolute deviation (MAD), repeatability coefficient (RC), and descriptive statistics. RESULTS: ICC scores for intra-rater repeatability were 0.917(0.897,0.933), 0.849(0.816,0.878), and 0.790(0.746,0.898), MAD results were 0.610 mm (± 0.508), 0.224 (± 0.200), and 0.067 (± 0.060), and RC results were 0.648, 0.327, and 0.121 for ABC-CEJ, GT, and ABT measurements, respectively. CONCLUSION: Results of the present study pointed towards good or excellent repeatability of ultrasound as a measurement tool for periodontal structures. CLINICAL RELEVANCE: Clinicians could benefit from the introduction of a novel chairside diagnostic tool. Ultrasound is a non-invasive imaging assessment tool for the periodontium with promising results in the literature. Further validation, establishment of scanning protocols, and commercialization are still needed before ultrasound imaging is available for clinicians.

Inhibition of neutrophil inflammatory mediator expression by azithromycin.

BACKGROUND AND OBJECTIVE: Peri-implant tissues appear to exhibit a more vigorous inflammatory response during post-operative healing than periodontal tissues. There is evidence that a single dose of amoxicillin (AMX) prior to implant surgery reduces the risk of early peri-implant healing complications. This study compared the effects of AZM and AMX on neutrophil expression of mRNA for mediators involved in peri-implant healing. MATERIALS AND METHODS: Neutrophils were isolated from healthy human donors and pre-incubated with AZM (4 or 8 µg/ml) or AMX (2 or 4 µg/ml). Cells were then incubated with LPS (1 µg/ml), TNF-α (10 ng/ml), or medium alone (control) for 1, 2, and 4 h. Total RNA was analyzed with qPCR to quantify changes in expression of the six inflammatory mediators. RESULTS: LPS and TNF-α induced a similar pattern of IL-1ß mRNA expression, with peak expression at 1 h. For most mediators, gene expression in neutrophils activated by LPS was markedly reduced in a dose-dependent manner by AZM. Therapeutic concentrations of AZM (8 µg/ml) consistently reduced expression of mediators tested in this study. AMX was effective only in a few cases and under certain conditions. Therefore, AZM was more effective in its direct anti-inflammatory action. CONCLUSION: AZM is a consistent and effective inhibitor of neutrophil inflammatory mediator mRNA expression. CLINICAL RELEVANCE: Given that a single dose of AZM produces higher and more sustained concentrations of this agent in periodontal tissues than AMX when used as a pre-operative prophylactic antibiotic, AZM has greater potential to inhibit inflammatory mediator expression at peri-implant wound sites than AMX.

FAM20C plays an essential role in the formation of murine teeth.

FAM20C is highly expressed in bone and tooth. Previously, we showed that Fam20C conditional knock-out (KO) mice manifest hypophosphatemic rickets, which highlights the crucial roles of this molecule in promoting bone formation and mediating phosphate homeostasis. In this study, we characterized the dentin, enamel, and cementum of Sox2-Cre-mediated Fam20C KO mice. The KO mice exhibited small malformed teeth, severe enamel defects, very thin dentin, less cementum than normal, and overall hypomineralization in the dental mineralized tissues. In situ hybridization and immunohistochemistry analyses revealed remarkable down-regulation of dentin matrix protein 1 (DMP1) and dentin sialophosphoprotein in odontoblasts, along with a sharply reduced expression of ameloblastin and amelotin in ameloblasts. Collectively, these data indicate that FAM20C is essential to the differentiation and mineralization of dental tissues through the regulation of molecules critical to the differentiation of tooth-formative cells.

Role of the NH2 -terminal fragment of dentin sialophosphoprotein in dentinogenesis.

Dentin sialophosphoprotein (DSPP) is a large precursor protein that is proteolytically processed into a NH2 -terminal fragment [composed of dentin sialoprotein (DSP) and a proteoglycan form (DSP-PG)] and a COOH-terminal fragment [dentin phosphoprotein (DPP)]. In vitro studies indicate that DPP is a strong initiator and regulator of hydroxyapatite crystal formation and growth, but the role(s) of the NH2 -terminal fragment of DSPP (i.e., DSP and DSP-PG) in dentinogenesis remain unclear. This study focuses on the function of the NH2 -terminal fragment of DSPP in dentinogenesis. Here, transgenic (Tg) mouse lines expressing the NH2 -terminal fragment of DSPP driven by a 3.6-kb type I collagen promoter (Col 1a1) were generated and cross-bred with Dspp null mice to obtain mice that express the transgene but lack the endogenous Dspp (Dspp KO/DSP Tg). We found that dentin from the Dspp KO/DSP Tg mice was much thinner, more poorly mineralized, and remarkably disorganized compared with dentin from the Dspp KO mice. The fact that Dspp KO/DSP Tg mice exhibited more severe dentin defects than did the Dspp null mice indicates that the NH2 -terminal fragment of DSPP may inhibit dentin mineralization or may serve as an antagonist against the accelerating action of DPP and serve to prevent predentin from being mineralized too rapidly during dentinogenesis.

Ultrasound Imaging of the Periodontium Complex: A Reliability Study.

Background: Ultrasonography is a noninvasive, low-cost diagnostic tool widely used in medicine. Recent studies have demonstrated that ultrasound imaging might have the potential to be used intraorally to assess periodontal biomarkers. Objectives: To evaluate the reliability of interlandmark distance measurements on intraoral ultrasound images of the periodontal tissues. Materials and Methods: Sixty-four patients from the graduate periodontics (n = 33) and orthodontics (n = 31) clinics were recruited. A 20 MHz handheld intraoral ultrasound transducer was used to scan maxillary and mandibular incisors, canines, and premolars. Distances between the alveolar bone crest and cementoenamel junction (ABC-CEJ), gingival thickness (GT), and alveolar bone thickness (ABT) were measured by 3 raters. The intercorrelation coefficient (ICC) and mean absolute deviation (MAD) were calculated among and between the raters. Raters also scored images according to quality. Results: The ICC scores for intrarater reliability were 0.940 (0.932-0.947), 0.953 (0.945-0.961), and 0.859 (0.841-0.876) for ABC-CEJ, GT, and ABT, respectively. The intrarater MAD values were 0.023 (±0.019) mm, 0.014 (±0.005) mm, and 0.005 (±0.003) mm, respectively. The ICC scores for interrater reliability were 0.872 (95% CI: 0.836-0.901), 0.958 (95% CI: 0.946-0.968), and 0.836 (95% CI: 0.789-0.873) for ABC-CEJ, GT, and ABT, respectively. The interrater MAD values were 0.063 (±0.029) mm, 0.023 (±0.018) mm, and 0.027 (±0.012) mm, respectively. Conclusions: The present study showed the high reliability of ultrasound in both intrarater and interrater assessments. Results suggest there might be a potential use of intraoral ultrasound to assess periodontium.

Inflammatory bowel disease and periodontitis: A retrospective chart analysis.

OBJECTIVES: This study examined the variation in prevalence of periodontitis among different sexes, age groups, smoking status, and oral hygiene adherence in patients affected by either Crohn's disease (CD) or ulcerative colitis (UC). MATERIALS & METHODS: This study was a retrospective chart analysis that collected data from the School of Dentistry's Oral Health Clinic at the University of Alberta, Edmonton, Canada. Patients' electronic health records between the years of 2013 and 2019 were analyzed. Multiple keywords such as IBD, CD, UC, and periodontal disease with various spelling combinations were used for searching and gathering pertinent data, which was then further assessed. After applying the inclusion and exclusion criteria, a total of 80 patient charts were included. These patient charts were thoroughly screened to gather information such as age, sex, smoking status, and a variety of periodontal parameters. Collected data were analyzed using SPSS software by using Pearson's χ2 , Pearson's correlation, and Mann-Whitney U-test. RESULTS: IBD had an impact on the severity of periodontitis in patients between the ages of 50 and 64 years with higher odds ratio (OR). Biological sex or history of smoking in IBD patients did not have higher odds of developing periodontitis. Plaque score derived from this retrospective study was used to estimate the patient's oral hygiene status and showed no impact. Also, prevalence of periodontitis did not differ between UC and CD. We anticipated some of these findings because of the retrospective nature of the study. CONCLUSIONS: Within the limitation of the retrospective study, IBD patients in the 50-64 age group years showed a higher odds ratio for a greater prevalence of periodontitis. Thus, a closer periodontal recall and evaluation in these patients is recommended for early diagnosis and preventive care. It is advised that periodontists work closely with gastroenterologists to maintain periodontal health in IBD-affected individuals.

Dental Students' Knowledge, Confidence, Ability, and Self-Reported Difficulties in Periodontal Education: A Mixed Method Pilot Study.

Evidence on periodontal education areas in which students have difficulties and their factors are limited. In this study, third- and fourth-year dental students' knowledge was assessed as well as their confidence and ability in five periodontal educational areas using a mixed-method approach. A survey was used to collect data related to history-taking, medical examination, diagnosis, treatment planning, and follow-up. Student answers were compared to the consensual answers of an expert panel using the cosine-similarity index (CSI). Descriptive statistics assessed confidence and ability for diagnosis. Semi-structured individual interviews were used to collect data on reported reasons for difficulties in periodontal education. A content analysis was employed to analyze the interview data. Eighteen third- and fourth-year dental students completed the survey and eleven were interviewed. Students' knowledge was adequate regarding diagnosis and treatment planning. Third-year students' median CSI were 0.93 and 0.89, respectively. Fourth-year students' median CSI were 0.9 and 0.93, respectively. Students felt confident in history-taking and examination but lacked confidence and ability in diagnosis and treatment planning. Reported reasons for difficulties in periodontal education were linked to both preclinical and clinical pedagogical issues. Further improvements in preclinical and clinical periodontal education are needed to address students' lack of knowledge, confidence, and skills in key periodontal areas.

Antibiotic prophylaxis for implant placement: a systematic review of effects on reduction of implant failure.

Introduction Despite excellent reviews in the past several years, the use of antibiotics as prophylaxis for implant placement remains controversial.Aim To assess the literature on the efficacy of prophylactic antibiotics prescribed prior to and immediately following implant surgery (PIFS).Outcomes Whether administration of antibiotics reduced implant failure and post-operative complications.Design Databases searched were PubMed and Medline via Ovid (1946 to February 2018), Cochrane Library (Wiley) and Google Scholar.Materials and methods Quality assessment, meta-analysis with a forest plot and incorporated assessment of heterogeneity. A two-tailed paired t-test was performed, analysing differences in mean failure rates between groups.Results Fourteen publications were collected; 5,334 implants were placed with pre-operative antibiotics, 82 implants with antibiotics PIFS and 3,862 placed with no antibiotics. The overall risk ratio (RR) was 0.47 (95% CI 0.39-0.58), with the implant failure rates significantly affected by pre-operative intervention (Z = 7.00, P <0.00001). The number needed to treat (NNT) was 35 (95% CI 26.3-48.2). The difference between mean failure rates was statistically significant (P = 0.0335).Conclusion Administering prophylactic antibiotics reduced the risk of implant failures. Further investigations are recommended to establish a standardised protocol for the proper use of antibiotic regimen.

Treatment of Gummy Smile of Multifactorial Etiology: A Case Report.

INTRODUCTION: This case report describes the management of a patient diagnosed with excessive gingival display caused by altered passive eruption and hyperactive lip. Treatment for this patient was staged and included esthetic crown lengthening and a subsequent lip repositioning procedure. CASE PRESENTATION: A 17-year-old female was referred for assessment of a "gummy smile." The patient reported a history of mouth breathing and a sports injury causing a non-vital tooth #9, which had been temporarily restored. After periodontal evaluation, the patient was diagnosed with plaque-induced gingivitis and excessive gingival display due to hyperactive lip and altered passive eruption. After initial therapy, an esthetic crown lengthening procedure was performed on the maxillary anterior sextant, resulting in ideal maxillary anterior crown contours. Six weeks after esthetic crown lengthening, the patient was treated for hyperactive lip by a modified lip repositioning surgery. Subsequently, the patient received a permanent restoration on tooth #9. During the 1.5-year follow-up time the patient repeatedly expressed her satisfaction with the improvement of her smile. Persistent mouth breathing and associated recurrent gingival inflammation remained a challenge. CONCLUSIONS: The presented case illustrates results of sequentially applied techniques for management of a gummy smile of multifactorial etiology and limitations imposed by unresolved factors. Excessive gingival display can be a significant esthetic concern for patients. Understanding the etiology can be challenging due to multiple factors that may be concomitantly involved. Accurate diagnosis and treatment planning are critical for proper management. When multifactorial etiology is present, multiple treatment modalities, including various surgical approaches, are necessary to obtain positive outcomes in such patients.

Transgenic expression of Dspp partially rescued the long bone defects of Dmp1-null mice.

Dentin matrix protein 1 (DMP1) and dentin sialophosphoprotein (DSPP) belong to the Small Integrin-Binding Ligand N-linked Glycoprotein (SIBLING) family. In addition to the features common to all SIBLING members, DMP1 and DSPP share several unique similarities in chemical structure, proteolytic activation and tissue localization. Mutations in, or deletion of DMP1, cause autosomal recessive hypophosphatemic rickets along with dental defects; DSPP mutations or its ablation are associated with dentinogenesis imperfecta. While the roles and functional mechanisms of DMP1 in osteogenesis have been extensively studied, those of DSPP in long bones have been studied only to a limited extent. Previous studies by our group revealed that transgenic expression of Dspp completely rescued the dentin defects of Dmp1-null (Dmp1(-/-)) mice. In this investigation, we assessed the effects of transgenic Dspp on osteogenesis by analyzing the formation and mineralization of the long bones in Dmp1(-/-) mice that expresses a transgene encoding full-length DSPP driven by a 3.6-kb rat Col1a1 promoter (referred as "Dmp1(-/-);Dspp-Tg mice"). We characterized the long bones of the Dmp1(-/-);Dspp-Tg mice at different ages and compared them with those from Dmp1(-/-) and Dmp1(+/-) (normal control) mice. Our analyses showed that the long bones of Dmp1(-/-);Dspp-Tg mice had a significant increase in cortical bone thickness, bone volume and mineral density along with a remarkable restoration of trabecular thickness compared to those of the Dmp1(-/-) mice. The long bones of Dmp1(-/-);Dspp-Tg mice underwent a dramatic reduction in the amount of osteoid, significant improvement of the collagen fibrillar network, and better organization of the lacunocanalicular system, compared to the Dmp1(-/-) mice. The elevated levels of biglycan, bone sialoprotein and osteopontin in Dmp1(-/-) mice were also noticeably corrected by the transgenic expression of Dspp. These findings suggest that DSPP and DMP1 may function synergistically within the complex milieus of bone matrices.