Evaluation of a biomarker based blood test for monitoring surgical resection of oral squamous cell carcinomas

Introduction

The potential use of determination of biomarkers in blood for the monitoring of surgical removal of oral squamous cell carcinomas (OSCC) was evaluated using the epitope detection in monocytes (EDIM) technology.

Materials and methods

In tumor specimen, elevated Apo10 and transketolase-like 1 (TKTL1) expression was analyzed by immunohistochemistry. Apo10 and TKTL1 biomarkers have been used prospectively for EDIM blood test in patients with primary and/or recurrent OSCC (n = 92) before surgery and after curative tumor resection (n = 45).

Results

There were highly significant (p < 0.0001) correlations found between EDIM blood scores and the tissue expression of both biomarkers measured by immunohistochemistry (Apo10: n = 89/92, 97 %; TKTL1: n = 90/92, 98 %). EDIMApo10 and EDIM-TKTL1 scores were positive in 92 % (EDIM-Apo10: n = 85/92) and 93 % (EDIM-TKTL1: n = 86/92), respectively, in patients with OSCC before surgery. The combined score EDIM-Apo10/EDIM-TKTL1 increased significantly the detection rate of tumors to 97 % (n = 89/92). After surgery, the EDIM-TKTL1 and EDIMApo10 scores significantly decreased in 75.6 and 86.7 % of the patients (p < 0.0001), respectively, in the aftercare.

Conclusions

The correlation of TKTL1 and Apo10 immunohistochemistry with the blood test results indicates that the EDIM blood test could serve as a non-invasive diagnostic tool (liquid biopsy) to assess surgical removal of OSCC by determination of two biomarkers.

Clinical relevance

This is the first study that has been demonstrated a reliable and successful monitoring of OSCC cancer patients by a blood test. The specific and significant decrease of EDIM-TKTL1 and EDIM-Apo10 scores after surgery could serve as a new tool for monitoring surgical removal of OSCC.

     

Influence of the bleaching interval on the luminosity of long-term discolored enamel-dentin discs

Objectives

The aim of this study is to investigate the influence of changing the sodium perborate-tetrahydrate (PBS-4) at a 4-day interval versus no change after 16 days of internal bleaching.

Materials and methods

Two hundred and ten bovine enamel-dentin discs were discolored for 3.5 years with 14 different endodontic materials. All groups with a discoloring index of ?E _(mean) ≥ 5.5 were included in the present investigation: ApexCal (APCA), MTA white + blood (WMTA+BL), Portland cement + blood (PC+BL), blood (BL), MTA gray (GMTA), MTA gray + blood (GMTA+BL), Ledermix (LED), and triple antibiotic paste containing minocycline (3Mix). Fourteen specimens of each group were randomly assigned into two treatment groups: (1) no change of the PBS-4 (n = 7); (2) change of the PBS-4 every 4 days (n = 7). Color measurements were taken at 10 different time intervals and the L*a*b* values were recorded with a spectrophotometer (VITA Easyshade® compact).

Results

In the group 3Mix, significantly better results were achieved by changing the bleaching agent every 4 days (P = 0.0049; q = 0.04), while the group WMTA+BL indicated better results by no change of the bleaching agent (P = 0.0222, q = 0.09). All remaining groups showed no statistical difference between the two treatment procedures.

Conclusions

Moderate discolorations can be successfully treated without changing the bleaching agent over a period of 16 days. Changing the sodium perborate-tetrahydrate every 4 days is preferred in case of severe discolored enamel-dentin discs only.

Clinical relevance

This approach may offer a reduced number of clinical appointments and a secondary cost reduction to the patient.

     

Effect of intervention using a messaging app on compliance and duration of treatment in orthodontic patients

Objectives

This study aims to determine the effectiveness of a messaging app (WeChat) in improving patients’ compliance and reducing the duration of orthodontic treatment (DOT).

Materials and methods

A randomized controlled trial was performed in a dental hospital and a clinic from August 2012 to May 2015. Orthodontic patients were included at the beginning of treatment. Patients with multiphase treatment or braceless technique were excluded. Participants were randomized to WeChat group (received regular reminders and educational messages) or control group (received conventional management) and were followed up until the treatment was completed. Primary outcome measure was DOT. Others were late and failed attendance, bracket bond failure, and oral hygiene condition.

Results

One hundred twelve patients in each group participated and completed the trial. DOT in WeChat group were 7.3 weeks shorter (P = 0.007). There were less failed attendance (3.1 vs. 10.9 %, P < 0.001), late attendance (20.1 vs. 29.9 %, P < 0.001), and bracket bond failure (11.8 vs. 16.1 %, P < 0.001) in WeChat group than control. There was no difference in orthodontic plaque index nor modified gingivitis index between the two groups before and after treatment. Number of failed attendances was identified as an independent factor affecting DOT (P = 0.004; HR = 0.89, 95 % CI 0.84 to 0.95).

Conclusions

The intervention with WeChat is effective in reducing the treatment duration and bracket bond failure, and improving the attendance in orthodontic patients.

Clinical relevance

DOT can be reduced by improving patient’s compliance. The messaging app is useful for outpatient education and management.

     

Fit of 4-unit FDPs from CoCr and zirconia after conventional and digital impressions

Objectives

To evaluate the marginal and internal fit of CAD/CAM-generated frameworks for 4-unit, fixed dental prostheses (FDPs) from zirconia (Z) and cobalt-chromium alloy (C) made with conventional (CI) and digital impressions (DI).

Materials and methods

A titanium model was digitized with an intraoral scanner (DI, LAVA? C.O.S.; 3M ESPE; Seefeld, Germany; n = 12). Additionally, 12 conventional impressions were taken, and referring plaster casts were digitized by a laboratory-scanner (CI, LAVA? Scan ST; 3M ESPE; n = 12). Frameworks were fabricated (3M ESPE) from cobalt-chromium (DI-C, n = 12; CI-C, n = 12) and zirconia (DI-Z, n = 12; CI-Z, n = 12) from the same datasets. A replica technique was applied to measure the accuracy. The Mann–Whitney U statistical test was applied to detect statistical differences between each material and methodology groups in terms of fit.

Results

Frameworks from DI-C (median 19.07 μm) showed significantly better marginal fit than CI-C (median 64.64 μm, p < 0.001). Frameworks from DI-Z (median 52.50 μm) showed significantly better marginal fit than CI-Z (median 72.94 μm, p = 0.001). Additionally, frameworks from DI-C showed a significantly better marginal fit than DI-Z (p < 0.001).

Conclusions

CI and DI led to a clinically acceptable marginal fit of 4-unit FDPs from cobalt-chromium and zirconia. DI leads to better marginal fit of the cobalt-chromium frameworks; however, no effect on zirconia was found.

Clinical relevance

The results indicate that DI is suitable for fabricating 4-unit, cobalt-chromium and zirconia frameworks with regard to fit requirements.

     

Prevalence of periodontitis in individuals with human leukocyte antigens (HLA) A9, B15, A2, and B5

Objective

Human leukocyte antigens (HLA) have been associated with periodontitis. Previous studies revealed HLA-A9 and HLA-B15 as potential susceptibility factors, while HLA-A2 and HLA-B5 might have protective effects. The aim of the study was to verify these associations in a group of HLA-typed blood donors with previously unknown periodontal status.

Materials and methods

In four German centers, 140 blood donors with known HLA class I status were enrolled and allocated to the following five groups: HLA-A9 (N = 24), HLA-B15 (N = 20), HLA-A2 (N = 30), HLA-B5 (N = 26), and controls (N = 40). Periodontal examination included the measurement of probing depths (PDs), clinical attachment level (CAL), bleeding on probing (BOP), and community periodontal index of treatment needs (CPITN).

Results

Carriers with HLA-A9 and HLA-B15 had higher values of mean PD (P < 0.0001), CAL (P < 0.0001), and BOP (P < 0.002) as well as sites with PD and CAL with ≥4 and ≥6 mm (P < 0.0003), respectively, than controls. Multiple regression analyses revealed HLA-A9, HLA-B15, and smoking as risk indicators for moderate to severe (CPITN 3–4; odds ratio (OR): 66.7, 15.3, and 5.1) and severe (CPITN 4; OR: 6.6, 7.4, and 3.8) periodontitis. HLA-A2 and HLA-B5 did not show any relevant associations.

Conclusion

The present data support a role of HLA-A9 and HLA-B15 as susceptibility factors for periodontitis, whereas HLA-A2 and HLA-B5 could not be confirmed as resistance factors.

Clinical relevance

Both HLA antigens A9 and B15 are potential candidates for periodontal risk assessment.

     

Oral dexamethasone decreases postoperative pain,swelling, and trismus more than diclofenac following third molar removal: a randomized controlled clinical trial

Purpose

The aim of this study was to compare the anti-inflammatory potential of two pharmacotherapy protocols based on the parameters of pain, trismus, and swelling, after extraction of third molars.

Methods

Thirty patients selected with symmetrical impaction of third molars were submitted to surgical procedures in both sides in different times. For one group, dexamethasone was used for 3 days, and for another group diclofenac sodium was also used for the same period. The main variables analyzed were the visual analogue pain scale (VAS), but others were also analyzed such as swelling and trismus, which were submitted to statistical analysis.

Results

The results had no difference regarding the length of procedures (p = 0.986) and the pain in the immediate and 4-h postoperative period (p = 0.723 and 0.541). The rescue analgesic consumption was higher (p < 0.05) when using the protocol with diclofenac sodium. The variables mouth opening (p < 0.05) and swelling (p < 0.05) were significantly better when using the protocol with dexamethasone in the postoperative period.

Conclusions

Medical protocol with the use of dexamethasone in the postoperative period was more effective in controlling pain, trismus, and swelling, after the extraction of third molars, when compared to diclofenac sodium.

     

Effect of therapeutic doses of radiotherapy on the organic and inorganic contents of the deciduous enamel: an in vitro study

Objectives

This study evaluated the effects of radiotherapy on the composition of deciduous teeth enamel using micro-energy-dispersive X-ray fluorescence and Fourier transform Raman spectroscopy before and after a pH cycling process.

Materials and methods

Ten deciduous molars were sectioned and divided into two groups (n = 10). The radiotherapy group (RT) was irradiated with 54 Gy at 2 Gy/day, 5 days per week for 5 weeks and 2 days, and the normal group (N) was not irradiated. The RT group was evaluated before radiotherapy (RTb), after radiotherapy (RTa), and after radiotherapy and pH cycling (RTc). The normal group was evaluated before (N) and after pH cycling (Nc). The weight percentage (wt%) of calcium (Ca), phosphorus (P), and organic content; the Ca/P ratio; and the integrated area of the Raman bands relative to the organic, carbonate, and phosphate contents were also evaluated.

Results

The exclusive use of RT reduced the organic content of the enamel (p = 0.000). The RTc group exhibited a decrease in P wt% (p = 0.016), an increase in the Ca/P ratio (p = 0.000), and a reduction in the integrated area of the phosphate band (p = 0.046). An increase in the Ca/P ratio (p = 0.000) and a reduction in the areas of the carbonate and phosphate bands were found in the RTb/RTc treatments.

Conclusions

RT application at a therapeutic dose reduced the organic content of the deciduous enamel.

Clinical relevance

Preventive measures should be included in the patient treatment protocol because of RT-induced chemical changes to the deciduous enamel.

     

Implant placement under existing removable dental prostheses and its effect on masticatory performance

Objective

The aim of this within-subject study was to evaluate the outcome with implant-tooth-supported removable partial dental prostheses (RPDP group) and implant-supported removable complete dental prostheses (edentulous group) in terms of masticatory performance and self-assessment.

Materials and methods

Thirty patients participated in this prospective clinical study (RPDP group: n = 12; edentulous group: n = 18). The prostheses were supported in strategically advantageous regions by placing implants with ball attachments and corresponding matrices in the existing dentures. The masticatory performance was evaluated with the Swallowing Threshold Test Index (STTI), the number of chewing strokes, and the time needed until swallowing at pre-treatment and 6 weeks after integration of ball attachments. Additionally, patients scored chewing satisfaction before and after implantation on a visual analogue scale.

Results

The STTI increased significantly (p ≤ 0.05) after implant therapy in the edentulous group but not in the RPDP group. Furthermore, the STTI was significantly higher (p ≤ 0.05) in the RPDP group than in the edentulous group at pre-treatment, however, not after therapy (P > 0.05). All patients were very satisfied after therapy concerning ability of speaking, chewing, and stability of their prosthesis.

Conclusions

Patients of the edentulous group benefit more from strategically placed implants under the existing dentures than patients from the RPDP group. However, according to the subjective assessment, the chewing satisfaction generally increased for both groups after implant therapy.

Clinical relevance

Patients with a strongly reduced dentition and edentulous patients benefit from strategically placed implants under the existing removable dentures.

     

In vitro analysis of the microbiological sealing of tapered implants after mechanical cycling

Objective

The aim of this in vitro study was to evaluate the mechanical behavior and bacterial microleakage at the implant/abutment-tapered interface following mechanical cycling.

Materials and methods

Two groups of screwless (Morse taper) implants (G1 and G2) and two groups of prosthetic screwed implants (G3 and G4) were tested. One group from each model (G2 and G4) were submitted to mechanical cycling, 500,000 cycles per sample, at a load of 120 N at 2 Hz prior to analysis. Microbiological analysis was performed via immersion of all samples in an Escherichia coli-containing suspension, incubated at 37 °C. After 14 days, the abutments were removed from their respective implants, registering the removal force (G1 and G2) or reverse torque (G3 and G4), and the presence of bacterial leakage was evaluated. Scanning electron microscopy (SEM) was performed to analyze the tapered surfaces of the selected samples. The Student t, binomial, and G tests were used for statistical analysis at a 5 % significance level.

Results

The results showed no significant difference between removal force, reverse torque, and contamination values when comparing implants of the same type. However, when the four groups were compared, contamination differed significantly (p = 0.044), with G1 having the least number of contaminated samples (8.3 %). SEM analysis showed superficial defects and damage.

Conclusions

The abutment removal force or torque was not affected by mechanical cycling. Bacterial sealing of the implant/abutment tapered interface was not effective for any condition analyzed. Imprecise machining of implant parts does not allow a sufficient contact area between surfaces to provide effective sealing and prevent bacterial leakage.

Clinical relevance

The microscopic gap caused by unsatisfactory implant/abutment adaptation, surface irregularities, and plastic deformation of all parts enabled bacterial contamination of the oral implants.

     

Effect of Alveolar Segmental Sandwich Osteotomy on Alveolar Height: A Preliminary Study

Purpose

Bone loss following extraction is maximum in horizontal dimension. Height is also reduced which is pronounced on the buccal aspect. Various surgical procedures are available to correct the bone volume viz. GBR, onlay bone grafting, alveolar distraction and sandwich osteotomy. Sandwich osteotomy has been found to increase the vertical alveolar bone height successfully.

Objectives

The objective of the study was to assess the effect of alveolar segmental sandwich osteotomy on alveolar height and crestal width.

Materials and Methodology

A prospective study was undertaken from December 2012 to August 2014. Seven patients with 12 implant sites with a mean age of 36 years were recruited. All seven patients with 12 implant sites underwent alveolar segmental sandwich osteotomy and interpositional bone grafting. Alveolar bone height was assessed radiographically preoperatively, immediate post-op, and at 3 months post-op. Alveolar bone width was assessed radiographically preoperatively and at 3 months post-op. Statistical significance was inferred at p < 0.05.

Results

The mean vertical augmentation at immediate post-op was 6.58 mm (p = 0.001). The vertical augmentation that was achieved 3 months post-op was a mean of 3.75 mm which was statistically significant (p = 0.004). The change in alveolar height from immediate post-op to 3 month post-op was a mean 1.69 mm. The mean change in alveolar crestal width at 3 months was a mean of ?0.29 mm (p = 0.57).

Conclusion

Sandwich osteotomy can be used as an alternative technique to increase alveolar bone height prior to implant placement. Moderate alveolar deficiency can be predictably corrected by this technique.

     

The impact of sexual behavior on oral HPV infections in young unvaccinated adults

Objective

Different authors hypothesized an important impact of sexual behavior on the prevalence of oral human papillomavirus (HPV) infections. In order to investigate this relationship more in detail and in contrast to most other studies, the present work focused on the population group with the highest risk for sexually transmitted infections: young and sexual active adults.

Materials and methods

Three hundred and ten men and women aged 18–30 years could be recruited. After the completion of a risk-factor survey, brush smear samples for oral HPV detection were taken in every participant.

Results

In 18.1 %, oral HPV could be detected. Overall, smoking (p = 0.0074) and a high number of different sexual partners (vaginal: p = 0.0001; oral: p < 0.0001) were significantly correlated with a positive HPV testing. In case of high risk HPV infections, besides tobacco and sexual behavior, alcohol consumption showed a significant association with a positive testing (p = 0.0212).

Conclusions

Overall, the prevalence of oral HPV seems to be higher in young, sexual active adults compared to other population groups. Tobacco and alcohol may facilitate an oral HPV infection. Sexual behavior, especially oral sex practices, seems to play a crucial role in the transmission of oral HPV.

Clinical relevance

The presented data, especially the association of oral high risk HPV positivity and promiscuity, may lead to improvements in the existing oral HPV prevention strategies like a HPV vaccination for both genders.

     

Comparison of Micromarsupialization and Modified Micromarsupialization for the Management of Mucocoele of Lower Lip: A Prospective Randomized Clinical Trial

Background

This study was undertaken to compare micromarsupialization and modified micromarsupialization for the management of mucoceles.

Materials and Methods

A prospective randomized clinical study was done on thirty patients having mucocele on lower lip. In Group A (n = 15), micromarsupialization and in Group B (n = 15), modified micromarsupialization technique was used. The outcome variables were duration of surgery, intraoperative pain, postoperative pain, healing and recurrence. t test and p values were used to compare the age, duration of lesion, duration of treatment and time taken for healing. The results were expressed as mean with SD. Statistical significance was established at the p ≤ 0.05 level. Analysis of pain (intraoperative, on 3rd, 7th day), intraoperative bleeding and recurrence was done using Fischer’s exact test (p = 0.875, NS).

Results

The average duration of treatment for Group A was 4.10 ± 0.39 min and for Group B was 5.33 ± 0.2 min. The difference was found to be statistically highly significant (p value ≤0.000). The observed power was 1.000. The difference in the intraoperative and postoperative pain on 3rd and 7th day was not found to be significant as per Fischer’s exact test. The mean time taken for healing of the surgical site in Group A was 7.47 ± 0.64 days and in Group B was 9.87 ± 1.88 days, and the difference was found to be highly significant. The observed power was 0.995.

Conclusions

Modified micromarsupialization appears to be a safe technique for the management of mucoceles. However, in comparison with micromarsupialization, it has a higher operating and healing time.

     

Detection of subgingival periodontal pathogens—comparison of two sampling strategies

Objective

The aim of the study is to compare detection frequency of periodontal pathogens in patients with aggressive/severe chronic periodontitis using pooled plaque samples from the deepest pockets per quadrant/per sextant.

Methods

In 100 patients with aggressive/chronic periodontitis, subgingival plaque was sampled from the deepest pockets per quadrant (MT4) and per sextant (MT6). Plaque samples were taken using two sterile paper points simultaneously. One paper point from each pocket was pooled with the three other paper points of the pockets (MT4). Subsequently, the remaining four paper points were pooled with two paper points from the deepest pockets from the two remaining sextants (MT6). The content of each vial was analyzed with nucleic-acid based methods for Aggregatibacter actinomycetemcomitans, Tannerella forsythia, Porphyromonas gingivalis, Treponema denticola, Prevotella intermedia, Parvimonas micra, Fusobacterium nucleatum, Campylobacter rectus, Eubacterium nodatum, Eikenella corrodens, and Capnocytophaga sp.

Results

The detection frequency of A. actinomycetemcomitans (MT4/MT6) at 22/24 %, T. forsythia at 93/96 %, P. gingivalis at 78/79 %, T. denticola at 88/90 %, P. intermedia at 40/46 %, P. micra at 75/79 %, F. nucleatum at both 99 %, C. rectus at 84/89 %, E. nodatum at 62/65 %, E. corrodens at 80/87 %, and Capnocytophaga sp. at 49/58 % was higher with MT6 than with MT4. None of these differences were statistically significant.

Conclusion

The detection frequency of the investigated periopathogens was statistically insignificant higher with the sampling method MT6 compared with MT4.

Clinical relevance

In daily dental practice, the plaque sampling of the deepest pockets per quadrant seems to be sufficient.

     

Quantification of circumferential bone level and extraction socket dimensions using different imaging and estimation methods: a comparative study

Objective

No studies have yet evaluated linear alveolar bone levels and extraction socket dimensions on dry skulls using different techniques. We aimed to investigate the accuracy of cone-beam computed tomography (CBCT), digital radiography, and digital photography.

Methods

Circumferential linear alveolar bone level measurements were performed at six sites on the examined teeth using gutta-percha points placed for reference at the cementoenamel junction and alveolar bone crest. Dimensions of the extraction socket were evaluated by linear measurements in the mesiodistal and buccolingual directions. Groups were formed according to the following imaging and estimation techniques: (1) direct measurement using digital calipers under loupe magnification (gold standard); (2) direct measurement using only digital calipers; (3) digital photographs/ImageJ (Photo/I); (4) digital paralleling long-cone periapical radiographs/ImageJ (Periapical/I); (5) digital panoramic radiographs/digital calipers; (6) digital panoramic radiographs/digital calipers and loupe magnification; (7) digital panoramic radiographs/ImageJ; and (8) CBCT/ImageJ (CBCT/I).

Results

Statistical analyses showed significant differences for all panoramic radiography subgroups in all examined regions compared with the gold standard (p < 0.001). Results of the CBCT/I (r = 0.930, p < 0.01), periapical/I (r = 0.939, p < 0.01), and Photo/I (r = 0.978, p < 0.01) techniques showed high correlation with the gold standard. Reliability of repeated measurements was higher with loupe magnification and the image-processing program.

Conclusions

Periapical/I and CBCT provide promising results in analyses of the dimensions and relations of periodontal tissues. Routine clinical digital photographs can be converted to scaled images and applied to treatment planning and preoperative–postoperative comparisons.

     

The impact of the new scene drug “crystal meth” on oral health: a case–control study

Objective

The use of methamphetamine (MA), a highly addictive stimulant, is rapidly increasing, with MA being widely abused as the scene drug “Crystal Meth” (CM). CM has been associated with severe oral health effects, resulting in so-called “Meth mouth”. This term appeared for the first time in 2005 in the literature and describes the final complex of symptoms including rampant caries, periodontal diseases and excessive tooth wear. The aim of this study was to investigate the effects of chronic CM abuse on teeth and intraoral tissue with respect to potential symptoms of Meth mouth.

Materials and methods

In cooperation with two centres for addiction medicine, we performed clinical intraoral investigations in 100 chronic CM users and 100 matched-pair controls. We undertook a caries and periodontal examination by using the clinical parameters DMF-T/DMF-S, bleeding on probing index (BOP) and periodontal screening index (PSI) and tested individual oral hygiene by using approximal space plaque index (API). All clinical data were analysed by the t test for independent samples.

Results

We found significantly larger numbers of caries (p < 0.001) and higher levels of gingival bleeding (p < 0.001) and periodontal disease (p < 0.001) among CM users. Oral hygiene was significantly lower in CM users (p < 0.024).

Conclusion

Chronic CM use can lead to extensive potential damage within the intraoral cavity. When CM is used over a long period of time and in the absence of treatment, clinical symptoms in terms of Meth mouth syndrome cannot be excluded.

Clinical relevance

Based on our results, we recommend a specific prevention and therapeutic concept including educational campaigns for MA users and specialized dental care for CM patients.

     

<Emphasis Type="Bold">S</Emphasis>hort fibre-reinforced composite for extensive direct restorations: a laboratory and computational assessment

Objectives

The objective of the study was to evaluate the effectiveness of a short fibre-reinforced composite (FRC) applied in combination with a conventional filler composite (CFC) on the fatigue resistance, fracture strength, failure mode and stress distribution, for restorations of premolars under two loading angles.

Material and methods

Thirty-two inferior premolars received extensive cavities with removal of the lingual cusp. Teeth were restored directly using ‘FRC (EverX Posterior, GC) + CFC (G-aenial, GC)’ or ‘CFC only’ and received two fatigue/fracture loadings at two different angles (0°/45°) (n = 8). Data were submitted to two-way ANOVA (α = 5 %) and Tukey test. Failure mode was analysed using SEM. Four 3D finite element (FE) models were constructed and static, linear and elastic analyses were performed. Maximum principal and von Mises stresses were evaluated.

Results

All specimens survived the mechanical fatigue simulation. No statistical difference in fracture resistance was recorded between FRC + CFC and CFC only, considering both loading angles (p = 0.115). However, the 0° loading showed a statistical significant higher strength than the 45° loading (p = 0.000). Failure mode analysis revealed more repairable fractures upon 0° loading, versus more root fractures (unrepairable) upon 45° loading. FE revealed a higher amount of stress upon 45° loading, with tensile stress being imposed to the lingual cervical area.

Conclusion

The fracture strength was not increased using the FRC. Loading at a 45° decreased significantly the fracture resistance.

Clinical relevance

The restoration of extensive cavities in posterior tooth is a challenge for the clinicians and the choice of the material that increases the fracture strength of tooth-restoration complex is required.

     

Effects of periodontal therapy on serum lipid profile and proinflammatory cytokines in patients with hyperlipidemia: a randomized controlled trial

Objective

The aim of this study was to evaluate whether periodontal treatment in patients with periodontitis and hyperlipidemia may have any influence on plasma lipids and pro-inflammatory cytokine levels.

Material and methods

We randomly assigned 109 patients with hyperlipidemia and chronic periodontitis into group 1 (n?=?55) and group 2 (n?=?54). Patients in group 1 underwent a standard cycle of supragingival mechanical scaling and polishing. Patients in group 2 underwent the adjunctive full-mouth intensive removal of subgingival dental plaque biofilms with the use of scaling and root planning. Periodontal parameters, total cholesterol (TC), triglyceride (TRG), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), tumor necrosis factor-alpha (TNF-α), interleukin(IL)-1β(IL-1β), and IL-6 were evaluated before treatment and 2 and 6 months after treatment.

Results

Two and 6 months after treatment, TRG levels were significantly lower in group 2 than in group 1 (P?<?0.05), and the levels of HDL-C were significantly higher (P?<?0.05). Two and 6 months after therapy, the levels of TNF-α were significantly lower in group 2 than in group 1 (P?<?0.05), as were the levels of IL-1β (P?<?0.001) and IL-6 (P?<?0.001).

Conclusions

Intensive periodontal treatment of participants with hyperlipidemia and chronic periodontitis improved serum lipid levels and decreased circulating pro-inflammatory cytokine levels.

Clinical relevance

This study showed that intensive treatment of periodontitis results in an improvement in serum lipid levels and a decrease in serum proinflammatory cytokine levels in patients with periodontitis and hyperlipidemia. These findings may contribute to present knowledge that periodontal therapy may be beneficial for individuals with hyperlipidemia.