Gingival Research Articles

The Incidence of Nasal Tip and Upper Lip Malposition in Primary Rhinoplasty.

In order to have an optimal aesthetic plan for correction of nasal tip disharmony, it is crucial to note lip and tip disproportions. This study sought to investigate the incidence of pre-operative upper lip malposition in primary rhinoplasty patients. 150 consecutive primary rhinoplasty patients were included. The position of the upper lip was measured during smiling relative to the incisors and gum line, and categorized as ideal, inadequate incisor show, or excessive gum show. Nasal length was categorized based on soft tissue cephalometic analysis of lifesize photographs as long, ideal and short. Tip projection was categorized as over-projected, ideal and under-projected. Columella was categorized as hanging, ideal or retracted. Standardized photos of 139 primary rhinoplasty patients met inclusion criteria. 49(35%) patients had an ideal upper lip position, 83(60%) inadequate incisor show, and 7(5%) excessive gum show. Sixteen (12%) had a short nose, 45(33%) ideal length and 76(55%) a long nose. 14(10%) had an under-projected tip, 38(28%) an ideal tip projection and 85(62%) an over-projected tip. None of the nasal parameters were predictive of upper lip position. Tip over-projection (OR 3.03, p=0.02) and hanging columella (OR 2.97, p=0.001) were predictive of a long nose. Tip under-projection was predictive of short length (OR 35, p<0.0001). There is a high incidence of upper lip malposition in patients undergoing primary rhinoplasty. It is vital for the rhinoplasty surgeon to identify it pre-operatively and plan the surgical maneuvers accordingly to prevent exacerbating an insufficient incisor show or excessive gum show.

Oral health and nutritional status in care-dependent, community-dwelling older adults in Zurich, Switzerland.

The aim of this study was to assess the oral health status (OHS), Oral health impact profile (OHIP-G-14), and the nutritional status (NS) in community-dwelling, dependent older adults. Information on OHS including DMF(T), plaque (PI) and gingival (GI) indices, community-periodontal-index-for-treatment-needs (CPITN), OHIP-G-14, maximum bite force (MBF), chewing efficiency [subjective (SA) and quantitative (VoH) assessments] were collected. NS was obtained by Mini-nutritional assessment (MNA) and body mass index (BMI). Cognitive status was evaluated by the mini-mental state examination (MMSE). 240 elders (mean-age = 81.5 ± 8.9y; men =85, women =155) were recruited. Average number of teeth, functional occlusal units and DMF(T), were 18.8 ± 8.9, 7.7 ± 3.5, and 22.3 ± 5.3 respectively. Mean PI, GI, CPITN and OHIP-G-14 were 1.8 ± 0.8, 1.2 ± 0.8, 1.9 ± 1.1, and 8.0 ± 12.0, respectively. MBF, VoH, SA were 219.6 ± 193.6, 0.3 ± 0.2, and 3.3 ± 1.4, respectively. MNA and BMI were 22.9 ± 4.7 and 25.5 ± 5.3, respectively. Number of teeth reduced significantly with age (P < 0.001), cognitive decline (P < 0.001). Oral hygiene significantly deteriorated with cognitive decline (P < 0.001). OHIP scores were negatively affected by increasing cognitive decline (P < 0.001). MNA deteriorated in women (P = 0.026), with increasing age (P = 0.015), and advancing cognitive decline (P < 0.001). BMI reduced with advancing age (P = 0.003) and in women (P = 0.016). Based on the findings of this study, it may be concluded that advancing age and cognitive decline, negatively impacted the oral health, oral function, oral health-related quality of life, and the nutritional state of care-dependent community-dwelling older adults.

A comparative evaluation of nano curcumin gel versus nano doxycycline gel in treatment of chronic periodontitis stage II grade B

Purpose Nanoparticles have many advantages as they have very small size and can penetrate extracellular and intracellular areas such as gingival fluid, bacterial cells, from the gingival sulcus to the underlying connective tissue and to the periodontal pocket areas below the gum line that may be inaccessible to other delivery systems. So, this study aimed to evaluate nano curcumin gel versus nano doxycycline gel in the treatment of periodontitis stage II grade B. Patients and methods This study was conducted on thirty sites among 22 patients with periodontitis stage II grade B. They were classified randomly into two treatment groups: Curcumin group (G1): consisting of 15 sites were treated by scaling and root planning (SRP) plus nano curcumin gel 2% and Doxycycline group (G2): consisting of 15 sites were treated by SRP plus nano doxycycline gel (20 mg/ml). Clinical evaluations including probing pocket depth (PPD), clinical attachment level (CAL) and bleeding on probing (BOP) were done before starting phase I therapy (zero time) 1 month after finishing phase I therapy (baseline), at 3 months and 6 months after baseline. Level of interleukin-6 (IL-6) was evaluated at zero time, 3 and 6 months after baseline. Results Intra group comparison of both groups showed a statistically significant reduction (P ≤ 0.05) regarding PD, CAL, and BOP from zero time to 6 months follow-up periods. Also, the level of IL-6 in GCF was reduced significantly up to 6 months (P ≤ 0.05). However, inter group comparison between the two studied groups was nonsignificant regarding to PD, CAL, BOP, and level of IL-6 (P &gt; 0.05). Conclusion Both nanocurcumin gel 2% and nano doxycycline gel 20 mg significantly improved PD, CAL and BOP and reduce IL-6 level until 6 months when applied as adjunct to scaling and root planning. So, nano drugs gels (nanocurcumin gel and nano doxycycline gel) are considered useful new modalities in treatment of periodontitis.

Nonsurgical periodontal therapy

Nonsurgical periodontal therapy (NSPT) aims to eliminate both living bacteria in the microbial film and calcified biofilm microorganisms from the tooth and adjacent soft tissues. It has traditionally been carried out using hand and powered instruments; it is less invasive, more cost-effective, and easily applied in different clinical settings. It generally includes scaling, root planing, antimicrobial therapy, laser therapy, and gum line therapy. Hence, NSPT is the gold standard against which other treatment options are compared.

Overview of microbes in hypertension

High blood pressure (BP), known as hypertension, is a major contributing factor to the development of cardiovascular disease. The development and pathogenesis of hypertension involve a wide array of factors including genetics, environment, hormones, hemodynamics, and inflammation. There is a significantly positive association between higher levels of colonization by Aggregatibacter actinomycetemcomitans , Porphyromonas gingivalis , Tannerella forsythia , and Treponema denticola (etiologic bacterial burden) below the gum line, and the presence of hypertension. The use of antibiotics during pregnancy, which is likely indicative of bacterial infections severe enough to require antibiotic treatment, is associated with a slight increase in average arterial BP. Cytomegalovirus infection is a risk factor for heightened arterial BP and acts as a co-factor in the development of aortic atherosclerosis. The relationship between hypertension and coronavirus disease 2019 involves endothelial dysfunction and dysregulation of the renin-angiotensin system. The effects of gut microbiota on BP, whether beneficial or harmful, are influenced by multiple factors including genetics, epigenetics, lifestyle choices, and antibiotic usage. These variables collectively contribute to overall BP levels and the control of hypertension. Several reports have examined the BP levels of patients infected with the Zika virus. In regions with a high incidence of nasopharyngeal carcinoma, hypertension has been linked to a higher risk of Epstein-Barr virus reactivation. Also, a potential causal link has been found between malaria and elevated BP. Also, the elevated prevalence of hypertension among dengue patients during their initial visit suggests that relying solely on BP measurements to predict severe infection may not be clinically reliable.

Planing, probing and pockets: progress in Perio or more of the same?

It is all too easy to think that nothing has changed in periodontology in the past 50 years. Self-performed plaque control, avoidance of the known risk factors and professional removal of deposits above and below the gum line have been the mainstay of periodontal management for decades. However, our understanding of what we actually need to do to the root surface to facilitate periodontal healing has changed dramatically in the past 50 years and advances in surgical technique and regenerative materials have made treatment more conservative, allowing us to predictably treat periodontitis. CPD/Clinical Relevance: The changes in periodontal management during the 50 years that Dental Update has been in circulation are highlighted.

EXPERT SYSTEM APPLICATION FOR DIAGNOSIS OF DENTAL DISEASES BASED ON WEBSITE USING BAYESIAN THEOREM METHOD

Teeth are small parts located in the upper or lower jaw. Each tooth is embedded in the gums, with its roots penetrating the gum line and entering the jawbone. The total number of teeth in the upper and lower jaw is 32. Teeth are divided into five types, each with a different function. Maintaining dental health is very important, as there are various dental diseases caused by leftover food consumed. Therefore, researchers have developed a system for diagnosing dental diseases by collecting symptoms that have been gathered through interviews with experts and patients, as well as collecting journals related to teeth. Then, all the data is entered into the application to determine the probability of the patient having a certain type of dental disease using the Bayes Theorem method.

Clinical and Antinociceptive Effects of Distal Inferior Alveolar Nerve Block in Ponies With Tramadol 5% or Lidocaine 2.

This study aimed to compare the antinociceptive effects of tramadol 5% and lidocaine 2% on mental nerve block in horses of the Brazilian Pony breed. Eight adult non-pregnant mares were used in this study. The ponies were tranquilized with acepromazine (5 µg kg-1, IV), and the infiltration of the mental foramen was performed in Treatment 1- tramadol 5% (T, 150 mg) or Treatment 2- lidocaine 2% (L, 60 mg), both at a total dose of 3 ml in each foramen. Heart rate (HR), respiratory rate (RR), systolic arterial pressure (SAP), diastolic arterial pressure (DAP), mean arterial pressure (MAP), rectal temperature (RT), and formation of skin lesions (SL) were evaluated. Evaluation of nociception of the outer lip (OL), inner lip (IL), and gingiva (GG) were performed using an electronic von Frey device with the evaluation of the ponies' reactions to each stimulus. From these reactions, we determined latency time (LT) and duration of antinociception (DAN). Analysis of variance with 16 observations was performed for HR, RR, SAP, DAP, MAP, LT and DAN. Data were expressed as mean ± standard deviation and the means were compared by the SNK and Student's t-test (P< 0.05). Changes in HR, RR, SAP, DAP, and MAP between evaluation times were associated with the effects of acepromazine (P>0.05). No formation of skin lesions was observed. Latency time did not differ between treatments (P>0.05). Both lidocaine 2% and tramadol 5% produced an antinociceptive effect. We conclude that the duration of the antinociceptive effect of tramadol 5% is longer than that of lidocaine 2%.

Keep your teeth for life: Wellness experience teeth cleaning

Keep your teeth for life: Wellness experience teeth cleaning The mouth contains bacteria and is a dynamic environment. Day and night, there is significant activity taking place between different types of bacteria. Some of these bacteria can become unstable and gain the upper hand over balanced, health-promoting bacteria, in time resulting in conditions like caries, bad breath, and / or gum inflammation, with signs of bleeding or spaces or openings surrounding the teeth under the gum line. This often necessitates thorough teeth cleaning, or more. Dr Marcel Donnet and Dr Neha Dixit discuss oral hygiene and the importance of teeth cleaning to maintain physical wellness.

PSUN339 Persistent Hypoglycemia and Hyperinsulinism in a Patient With Kabuki Syndrome Type 1.

Abstract Background Transient neonatal hypoglycemia typically resolves within the first few days of life. Persistence of neonatal hypoglycemia is a more significant finding that warrants further investigation. Clinical case A 2-year-old female born at 37 weeks of gestation via C-section due to a history of maternal preeclampsia. Delivery was complicated by meconium aspiration syndrome for which the patient was admitted to the NICU where she had a prolonged course. Patient was initially depressed at birth with APGARs of 3/6/8 at 1, 5 and 10 minutes of life, respectively. During the neonatal period, she had multiple complications including GERD, FTT (G-tube was placed), recurrent UTIs, congenital heart disease (mild RVH and ASD) and hypoglycemia. Regarding her hypoglycemia, the initial work up was suggestive of hyperinsulinism with a critical sample remarkable for a BG: 57 mg/dl (60-100mg/dl), Insulin level: 8.3 uUm/mL Subsequent glucagon challenge test confirmed hyperinsulinism. She initially required a continuous glucose infusion and Diazoxide was started. She was discharged home on Diazoxide and Diuril. Subsequently, Diazoxide was successfully discontinued at the age of 2 months. A Congenital Hyperinsulinism genetic panel was negative for the most frequent mutations. At 11 months old, she presented to our clinic due to persistent hypoglycemia when enteral feeds were attempted to be spaced. Patient was started on cornstarch which was discontinued secondary to frequent diarrhea. SolCarb was started with enteral feeds with good tolerance and response, maintaining target blood glucose levels. On physical examination, she had some dysmorphic features that were suggestive of a syndromic condition: prominent ear lobes, broad and flat nasal bridge, a single prominent tooth at the center of the bottom gum line, long palpebral fissures with upward curvature at the lateral edges, prominent finger pads and neurodevelopmental delay. Since she had features suggestive of Kabuki syndrome, WES was ordered which was remarkable for a pathogenic mutation in KMT2D (Autosomal dominant, Heterozygous, variant c.5269C&amp;gt;T and p.R1757X). Conclusion Persistent hypoglycemia beyond the neonatal period is a rare finding in Kabuki syndrome. In addition, it is a more common finding in Kabuki Syndrome type 2 (Mutations in the KDM6A gene). Our patient presents a rare case of a 2-year-old female with persistent hypoglycemia and hyperinsulinism secondary to KS1. Presentation: Sunday, June 12, 2022 12:30 p.m. - 2:30 p.m.

Cavitation in a periodontal pocket by an ultrasonic dental scaler: A numerical investigation

Periodontal pockets are spaces or holes surrounded by teeth under the gum line. These pockets can become filled with infection-causing bacteria resulting in tissue, bone, and tooth loss. Cavitation produced by the oscillating tip of dental ultrasonic scalers plays a significant role in routine periodontal therapy to clean these areas. Numerical studies were conducted for a scaler vibrating in a periodontal pocket which was simplified to a hole, using ABAQUS based on the finite element method. The simulations consider the three-dimensional, nonlinear, and transient interaction between the vibration and deformation of the scaler tip, the water flow around the scaler and the cavitation formation. The numerical model was validated by comparing results with experimental data for a scaler vibrating in an unbounded liquid, the displacement at the free end of the scaler and the cavitation pattern near the scaler tip displaying excellent agreement. A parametric study for a scaler vibrating in a hole has been carried out in terms of the volume of the hole, the taper ratio (the radius ratio between the circular opening and bottom of the hole), and the immersion depth of the scaler tip in the hole. The amount of cavitation generated is evaluated by the cavitation density (or the void fraction) which is the ratio of the volume of the cavitation occupied in the hole to the total volume of the hole. Numerical results indicate that the cavitation density in the hole increases with the decreasing hole volume and the increasing taper ratio. It is inferred that cleaning effects could be increased if some modifications to the scaler design could be made to increase the blocking effect of the hole during the cleaning process. Cavitation is observed in the hole even if the scaler is placed above the hole and increases with the immersion depth.

Host and bacterial factors linking periodontitis and rheumatoid arthritis.

Observations from numerous clinical, epidemiological and serological studies link periodontitis with severity and progression of rheumatoid arthritis. The strong association is observed despite totally different aetiology of these two diseases, periodontitis being driven by dysbiotic microbial flora on the tooth surface below the gum line, while rheumatoid arthritis being the autoimmune disease powered by anti-citrullinated protein antibodies (ACPAs). Here we discuss genetic and environmental risk factors underlying development of both diseases with special emphasis on bacteria implicated in pathogenicity of periodontitis. Individual periodontal pathogens and their virulence factors are argued as potentially contributing to putative causative link between periodontal infection and initiation of a chain of events leading to breakdown of immunotolerance and development of ACPAs. In this respect peptidylarginine deiminase, an enzyme unique among prokaryotes for Porphyromonas gingivalis, is elaborated as a potential mechanistic link between this major periodontal pathogen and initiation of rheumatoid arthritis development.

MicroRNAs and Periodontal Disease: Helpful Therapeutic Targets?

Periodontal disease is the most common oral disease. This disease can be considered as an inflammatory disease. The immune response to bacteria accumulated in the gum line plays a key role in the pathogenesis of periodontal disease. In addition to immune cells, periodontal ligament cells and gingival epithelial cells are also involved in the pathogenesis of this disease. miRNAs which are small RNA molecules with around 22 nucleotides have a considerable relationship with the immune system affecting a wide range of immunological events. These small molecules are also in relation with periodontium tissues especially periodontal ligament cells. Extensive studies have been performed in recent years on the role of miRNAs in the pathogenesis of periodontal disease. In this review paper, we have reviewed the results of these studies and discussed the role of miRNAs in the immunopathogenesis of periodontal disease comprehensively. miRNAs play an important role in the pathogenesis of periodontal disease and maybe helpful therapeutic targets for the treatment of periodontal disease.

Oral Health Status among a Group of Population with Chronic Kidney Disease in Iraq

Background: Chronic kidney disease (CKD) has been identified as one of the irreversible deteriorations in renal function that naturally progresses over years. This disease has been considered as one of the worldwide public health problems that have reverse consequences of kidney failure, cardio-vascular diseases as well as premature mortality. The present study was conducted to assess the seriousness of dental caries in association with the oral cleanliness among patients suffering from CKD compared to the controls according to age groups and gender. Materials and Methods: This research employed thirty patients with CKD in ages from (24–72) years (male, female) attending kidney center centers in Medical City Teaching Hospital in Baghdad province, Iraq, were selected for the study compared to 30 healthy people matching in age and genders with the study group. Decayed, missing and filled surfaces (DMFS), Gingival (GI), calculus (CI) indices as well as plaque (PlI) have been applied for measuring oral health status for these two study groups. The data of current study was analyzed using SPSS version 26. Result: The (CKD) group has been caries-active. The greater DMFS-values have been registered for the study in comparison with the control group and highly statistical difference has been observed, concerning DMFS (p is less than 0.01). (DS, MS, FS) higher in CKD patients than control with highly significant difference between them regarding to (DS, MS) only. PlI, GI, indices have been greater in the study group than that of the controls and differences were not observed to be significant. The CI index has been greater in the study group than that of the controls and significant differences have been observed (p is less than 0.01). Significant correlation has been not found between PlI, GI, CI indices and DMFS indices in study group. Conclusion: Participants suffering from (CKD) experienced greater caries severity than the normal participants.

Man with jaw pain after complicated wisdom tooth extraction

A 57-year-old male with history of hypertension and hyperlipidemia presented to the emergency department (ED) complaining of left jaw pain and swelling. The patient was referred to the ED by an oral surgeon at an outside facility because of concerns about worsening periodontal infection after a second failed extraction of tooth #17 the day before. The patient had an incomplete extraction 46 days before complicated by postoperative wound infection treated with amoxicillin, later complicated by Clostridium difficile infection treated with oral vancomycin. On physical examination, the patient was afebrile with normal vital signs. The patient had mild trismus, left jaw swelling, and tenderness along the buccal gum line along the left jaw adjacent to teeth #15–17. A bedside ultrasound was performed along the left jawline (Figure 1). Oral surgery was consulted with concern about mandibular osteomyelitis due to cortical disruption visualized on the ultrasound. A subsequent maxillofacial computed tomography scan confirmed the disruption (Figure 2). Bedside ultrasound is a useful tool for evaluating unilateral face or neck swelling in the ED, as it can help distinguish between an abscess, lymphadenopathy, sialolithiasis, sialadenitis or other pathologies. In this case, bedside ultrasound led to the diagnosis of osteomyelitis when cortical disruption of the mandible was visualized. Cortical disruption visualized on ultrasound is a very specific finding, with one study done by Ezzat et al estimating 100% specificity in children.1 Emergency physicians should consider sonographic visualization of underlying bones to assess for underlying osteomyelitis when evaluating localized swelling.2, 3

The influence of fixed orthodontic retainer on oral microbiota

Background: The oral cavity is a wide versatile microbial community in which many microbial species coexist in harmony. However, with certain circumstances, i.e. orthodontic appliances, pathogenic biofilm outgrowth occurs. The aim: The aim of this study was to compare opportunistic pathogens, associated with dental caries and periodontal disease in addition to Candida albicans, between healthy individuals and patient wearing fixed orthodontic retainers. Method: Fourty eight subjects were recruited andwere divided into retainer wearers and control cohort groups. Biofilm samples from the lingual surface of the mandibular anterior teeth of the control group and the fixed retainer surface were evaluated to detect Streptococcus mutans, Lactobacillus acidophilus, Aggrigatibacter actinomycetemcomitans, Fusobacterium nucleatum and C. albicans. Additionally, plaque (PI) and gingival (GI) indices were measured at the mandibular anterior teeth in both groups. The results: The results showed a significant increase in total micobial count in retainer group (p&lt;0.001). The prevalence of microbial cultivity was higher in retainer group with a significant increase in PI and GI. Moreover, there was a high correlation between these genera and the GI. The conclusion: fixed retainer may increase cariogenic and periodontal pathogens and compromise oral health.

Influence of fixed orthodontic retainer on oral microbiota

Background: The oral cavity is a wide versatile microbial community in which many microbial species coexist in harmony. However, with certain circumstances, i.e. orthodontic appliances, pathogenic biofilm outgrowth occurs. The aim: The aim of this study was to compare opportunistic pathogens, associated with dental caries and periodontal disease in addition to Candida albicans, between healthy individuals and patient wearing fixed orthodontic retainers. Method: Fourty eight subjects were recruited andwere divided into retainer wearers and control cohort groups. Biofilm samples from the lingual surface of the mandibular anterior teeth of the control group and the fixed retainer surface were evaluated to detect Streptococcus mutans, Lactobacillus acidophilus, Aggrigatibacter actinomycetemcomitans, Fusobacterium nucleatum and C. albicans. Additionally, plaque (PI) and gingival (GI) indices were measured at the mandibular anterior teeth in both groups. The results: The results showed a significant increase in total micobial count in retainer group (p&lt;0.001). The prevalence of microbial cultivity was higher in retainer group with a significant increase in PI and GI. Moreover, there was a high correlation between these genera and the GI. The conclusion: fixed retainer may increase cariogenic and periodontal pathogens and compromise oral health.

Dentistry for veterinary nurses: what you can see in the consultation room

Registered veterinary nurses provide the tools for oral care, whether that be in the consulting room or in a dental suite. It is their job to make sure owners understand the importance of maintaining good oral hygiene to help their pet live a pain free life. This is done through dental clinics and being confident in the products and services being offered. Veterinary nurses can educate owners on the facts of dental disease and help them understand that most of the dental disease is below the gum line. It is also important to have sound knowledge on what normal looks like so that abnormalities can be detected.

10 - Functionalization of Restorative Dental Glass-Ceramics with Bactericidal Properties

Clinically, the periodontitis is related with the dental plaque, a biofilm of microorganisms, growth on the gum line and on the tooth interface. Therefore, a strategy to minimize this condition is the functionalization of the dental prosthesis, usually in contact with the gum, with antibacterial properties. The purpose of this study was to investigate the bactericidal potential of some commercial restorative glass-ceramic materials and to functionalize a commercial dental porcelain with antibacterial properties. Commercially available restorative glass-ceramics in powder (IPS d.SIGN), or as monolithic (IPS E.max Press e GC Initial LiSi Press) were used as control samples, and characterized by X-ray diffraction (XRD), Rietveld refinement, differential thermal analysis and particle size distribution. The IPS d.SIGN glass-ceramic was selected for functionalization with nanostructured β-AgVO 3 that was synthetized by a hydrothermal route, using AgNO 3 and NH 4 VO 3 as precursors, and characterized by XRD and Scanning Electron Microscopy (SEM). The glass-ceramic material was mixed with different percentages (1%, 2%, 4% or 6%wt) of β-AgVO 3 , uniaxially pressed at 50 MPa, and thermally treated at 900 C for 5 min, as indicated by the manufacturer. The functionalized glass-ceramics was characterized by XRD, Rietveld refinement, SEM, Vickers Hardness and Vickers indentation fracture toughness. The three commercial glass-ceramics, IPS d.SIGN, IPS E.max Press and GC Initial LiSi Press as well as the functionalized samples were evaluated for its bactericidal potential against model bacteria (Escherichia coli and Staphylococcus aureus). The as-received control samples presented leucite (KAlSi 2 O 6 ) as the only detectable crystalline phase, 62%wt of amorphous phase and a median particle size (D50) of 25.5 m in IPS d.SIGN. The product of the hydrothermal synthesis was characterized as pure needle like shaped β-AgVO 3 crystals. The heat-treated control samples still presented KAlSi 2 O 6 as the only detectable crystalline phase. However, a secondary feldspar (KAlSi 3 O 8 ) phase could be detected in the functionalized samples, which turns to be the main crystalline phase as a function of the increase in the β-AgVO 3 concentration. None of the commercially available samples showed antibacterial activity, but the IPS d.SIGN samples functionalized with 2%wt or more of β-AgVO 3 presented a clear inhibition halo, from 12, 70, 3 mm to 15, 50, 1 mm, suggesting bactericidal activity against both model bacteria. Preliminary, in vitro results indicated that the analyzed commercial dental glass ceramics demonstrated no antibacterial activity. Nevertheless, the functionalization of a commercially available veneering glass-ceramic with at least 2%wt of β-AgVO 3 can induce bactericidal activity against gram-positive and gram-negative bacteria.

Diversity of Treponema denticola and Other Oral Treponeme Lineages in Subjects with Periodontitis and Gingivitis.

ABSTRACTMore than 75 species/species-level phylotypes belonging to the genus Treponema inhabit the human oral cavity. Treponema denticola is commonly associated with periodontal disease, but the etiological roles and ecological distributions of other oral treponemes remain more obscure. Here, we compared the clinical distributions of phylogroup 1 and 2 oral treponemes in subgingival plaque sampled from Chinese subjects with periodontitis (n = 10) and gingivitis (n = 8) via sequence analysis of the highly conserved pyrH housekeeping gene. Two PCR primer sets that targeted oral phylogroup 1 and 2 treponeme pyrH genes were used to construct plasmid clone amplicon libraries for each subject, and the libraries were sequenced for bioinformatic analysis. A total of 1,204 quality-filtered, full-length pyrH gene sequences were obtained from the cohort (median number, 61.5 cloned pyrH sequences per subject; range, 59 to 83), which were assigned to 34 pyrH genotypes (designated pyrH001 to pyrH034; 97% sequence identity cutoff). Eighteen pyrH genotypes (536 pyrH sequences) corresponded to phylogroup 1 treponeme taxa (including Treponema vincentii and Treponema medium). Sixteen pyrH genotypes (668 pyrH sequences) corresponded to T. denticola and other phylogroup 2 treponemes. Samples from periodontitis subjects contained a greater diversity of phylogroup 2 pyrH genotypes than did samples from gingivitis subjects (Mann-Whitney U test). One T. denticola pyrH genotype (pyrH001) was highly prevalent, detected in 10/10 periodontitis and 6/8 gingivitis subjects. Several subjects harbored multiple T. denticola pyrH genotypes. Nonmetric multidimensional scaling and permutational multivariate analysis of variance (PERMANOVA) revealed no significant differences in overall pyrH genotype compositions between periodontitis and gingivitis subjects. Taken together, our results show that subjects with periodontitis and gingivitis commonly harbor highly taxonomically diverse communities of oral treponemes.IMPORTANCE Periodontal diseases, such as periodontitis, are highly complex, multifactorial inflammatory infectious diseases affecting the gums and tooth-supporting structures. They are caused by chronic accumulations of dental plaque below the gum line that typically comprise hundreds of different bacterial species. Certain species of spiral-shaped bacteria known as treponemes, most notably Treponema denticola, are proposed to play key roles in the development and progression of periodontal disease. In our study, we characterized the genetic lineages of T. denticola, Treponema vincentii, Treponema medium, and related species of treponeme bacteria that were present in dental plaque samples from Chinese subjects with periodontal disease. Our results revealed that individual subjects commonly harbored multiple genetic lineages (strains) of T. denticola and other species of treponeme bacteria. Taken together, our results indicate that highly diverse and complex populations of oral treponemes may be present in dental plaque, which may potentially play important roles affecting periodontal health status.