The Clinical Guiding Role of the Distribution of Corneal Nerves in the Selection of Incision for Penetrating Corneal Surgery in Canines

The cornea is one of the regions with the highest density of nerve terminals in the animal body and it bears such functions as nourishing the cornea and maintaining corneal sensation. In veterinary clinical practice, the corneoscleral limbus incision is frequently applied in cataract surgery, peripheral iridectomy, and other procedures for glaucoma. Inevitably, it would cause damage to the nerve roots that enter the cornea from the corneal limbus, thus inducing a series of complications. In this paper, the in vitro cornea (39 corneas from 23 canines, with ages ranging from 8 months old to 3 years old, including 12 male canines and 11 female canines) was divided into 6 zones, and the whole cornea was stained with gold chloride. After staining, corneal nerves formed neural networks at different levels of cornea. There was no significant difference in the number of nerve roots at the corneoscleral limbus between different zones (F = 1.983, p = 0.082), and the nerve roots at the corneoscleral limbus (mean value, 24.43; 95% CI, 23.43–25.42) were evenly distributed. Additionally, there was no significant difference in the number of corneal nerve roots between male and female canines (p = 0.143). There was also no significant difference in the number of corneal nerve roots between adult canines and puppies (p = 0.324). The results of the above analysis will provide a reasonable anatomical basis for selecting the incision location and orientation of penetrating surgery for the canine cornea in veterinary practice.

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Milled versus moulded mock-ups based on the superimposition of 3D meshes from digital oral impressions: a comparative in vitro study in the aesthetic area

BMC Oral Health ◽

10.1186/s12903-019-0922-2 ◽

2019 ◽

Vol 19 (1) ◽

Cited By ~ 14

Author(s):

Francesca Cattoni ◽

Giulia Teté ◽

Alessandro Mauro Calloni ◽

Fabio Manazza ◽

Giorgio Gastaldi ◽

...

Keyword(s):

Statistical Analysis ◽

Test Group ◽

In Vitro Study ◽

Mean Value ◽

Digital Impression ◽

Control Group ◽

Minimal Invasiveness ◽

Significant Difference ◽

The Aesthetic

Abstract Background Aesthetic porcelain veneers proved to be a long-term reliable prosthetic solution, ensuring minimal invasiveness. The use of veneers requires an adhesive cementation technique, so maintaining as much enamel as possible is to ensure lasting success. A diagnostic mock-up is a key tool that allows a preview of the outcome of the aesthetic restoration: it is obtainable both in an analog and digital way. With the recent developments in impression technology and the ever so fast growing use of CAD-CAM technologies it is useful to understand the pros and cons of either one of these techniques (analog and digital) in order to identify the easier and more convenient workflow in aesthetic dentistry. Methods After taking pictures and impressions of the dental arcs of a patient in need of aesthetic rehabilitation, 52 resin models were produced and a digital drawing of the smile was outlined. Both an analog and a digital wax-up were obtained from two of the 52 models: the latter was obtained using digital impressions and a dedicated software. The analog wax-up was then used to produce 25 matrices that have later been used to mould 25 resin mock-ups using a traditional moulding protocol (Control Group - CG). The digital wax-up was used to mill 25 PMMA mock-ups. Each mock-up, both milled and moulded (total 50), was then laid on the other 50 resin models as a digital impression of it was taken. The STL. files of the milled mock-ups were compared with the 3D CAD wax-up made using a specific software. The STL. files of the analog printed mock-ups were compared with the traditional wax-up design. A statistical analysis was carried out to evaluate the difference between the groups. Results The statistical analysis showed a significant difference (P > 0.01) between the mean value of the distance between the points of the overlapping STL. meshes in GC (0.0468 mm) and in TG (Test Group - TG) (0,0109 mm). Conclusions The study showed a difference in accuracy between traditional moulded and milled mock-ups compared to their original wax-up. The data analysis reports that the digital method allows for greater accuracy. Within the limitations of this study, a fully digital workflow is to considered more reliable when it come to creating an esthetic mockup: the digital procedure has been shown to be more accurate than the one made manually which is much more operator dependent and it brings an increase to the chance of error, and that could ultimately affect the final result.

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Dental implant location via surface scanner: a pilot study

BMC Oral Health ◽

10.1186/s12903-020-01297-y ◽

2020 ◽

Vol 20 (1) ◽

Author(s):

Miao Zhou ◽

Hui Zhou ◽

Shu-yi Li ◽

Yuan-ming Geng

Keyword(s):

Dental Implant ◽

Clinical Investigation ◽

Mean Value ◽

Angular Deviation ◽

Surface Scanning ◽

Anatomic Structure ◽

Vertical Deviation ◽

Significant Difference ◽

The Mean

Abstract Purpose Implant location is performed after placement to verify that the safety of neighboring anatomic structure and the realizability of prosthetic plan. Routine postoperative location is based on radiological scanning and raises the concerns on radiation exposure and inconveniency in practice. In the present study a location method based on surface scanning was introduced and the accuracy of this method was assessed in vitro. Material and methods A total of 40 implants were placed in 10 resin mandible models. The models were scanned with intraoral scanner (IS group) and extraoral scanner (ES group). The implant position was located with fusing the images of surface scanning and cone beam computerized tomography (CBCT) after implant placement. Deviations were measured between positions located by surface scanner and postoperative CBCT with the parameters: central deviation at apex (cda), central deviation at hex (cdh), horizontal deviation at apex (hda), horizontal deviation at hex (hdh), vertical deviation at apex (vda), vertical deviation at hex (vdh) and angular deviation (ad). Results In IS group, the mean value of cda, cdh, hda, hdh, vda, vdh and ad was 0.27 mm, 0.23 mm, 0.12 mm, 0.10 mm, 0.21 mm, 0.19 mm and 0.72°, respectively. In ES group, the mean value of cda, cdh, hda, hdh, vda, vdh and ad was 0.28 mm, 0.25 mm 0.14 mm, 0.11 mm, 0.22 mm, 0.20 mm and 0.68°, respectively. The implant deviations in IS and ES groups were of no significant difference for any of the measurements. Conclusions Dental implant can be located via surface scanner with acceptable accuracy for postoperative verification. Further clinical investigation is needed to assess the feasibility of the method.

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Study of Morphokinetics in Day 3 Embryo with Implantation Potential and Effect of Sperm Cryopreservation on Embryogenesis

International Journal of Infertility & Fetal Medicine ◽

10.5005/jp-journals-10016-1150 ◽

2017 ◽

Vol 8 (2) ◽

pp. 61-67

Author(s):

Harsha K Bhadarka ◽

Nayana H Patel ◽

Kruti B Patel ◽

Nilofar R Sodagar ◽

Yuvraj D Jadeja ◽

...

Keyword(s):

Time Lapse ◽

Mean Value ◽

Primary Objective ◽

Sperm Cryopreservation ◽

Cell Stage ◽

Frozen Semen ◽

Significant Difference ◽

Cryopreserved Sperm ◽

Day 3 Embryo

ABSTRACT Aim In recent past, many studies had come up with the combination of time-lapse (TL) imaging of embryo morphokinetics as a noninvasive means for improving embryo selection and in vitro fertilization (IVF) success. The primary objective of the study was to find out if there is significant variation in morphokinetics of embryos with different implantation potential and also to study the effect of sperm freezing on time points of embryogenesis events in embryos with implantation potential. Materials and methods Kinetic data and cycle outcomes were analyzed retrospectively in 142 patients who had undergone IVF/intracytoplasmic sperm injection (ICSI) cycles using semen with normal parameters and embryo transfer (ET) on day 3. For the surety of specificity of morphokinetics, only cases with single ET cycles were included in the study. Timing of specific events, from the point of ICSI, was determined using TL imaging. Kinetic markers like time to syngamy (t-pnf), t2, time to two cells (c), 3c (t3), 4c (t4), 5c (t5), 8c (t8), tMor, CC2, CC3, t5–t2, t5–t4, s1, s2, and s3 were calculated. The cleavage synchronicity from the 2–8 cell stage (CS2–8), from 4 to 8 cell stage (CS4–8), and from 2 to 4 cell stage (CS2–4) were calculated as defined elsewhere. Deoxyribonucleic acid replication time ratio (DR) was also included in the comparison. Analysis of variance test was used for comparison of the mean timing of cell division and cell cycle intervals. Results Morphokinetics t-pnf, t2, t8, CC2, S2, S3, CS2–8, CS4–8, and CS2–4 differed significantly between embryos with and without implantation potential, when embryos were developed using fresh semen, while t3, t4, t5, CC2, S2, t5–t2, CS2–4, and DR differed significantly between the embryos with and without implantation potential when frozen semen was used. No significant difference was found in mean value of any of the above-stated parameters when comparison was done between implanted embryos fertilized by either fresh or cryopreserved sperm. Conclusion Many morphokinetics parameters of embryogenesis vary significantly between embryos with different ability to implant; therefore, the criteria developed in our IVF lab can be useful for selection of suitable embryo even at day 3 of development with more chances of implantation. Clinical significance Study indicates necessity of development of individualized selection model based on morphokinetics for every IVF lab and also confirms freezing as an important tool for fertility preservation of males as it does not affect events of embryogenesis. How to cite this article Bhadarka HK, Patel NH, Patel KB, Sodagar NR, Jadeja YD, Patel NH, Patel MN, Patel AV, Patel DH, Patel JS. Study of Morphokinetics in Day 3 Embryo with Implantation Potential and Effect of Sperm Cryopreservation on Embryogenesis. Int J Infertil Fetal Med 2017;8(2):61-67.

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Influence of Toothbrush Abrasion and Surface Treatments on Roughness and Gloss of Polymer-Infiltrated Ceramics

Polymers ◽

10.3390/polym13213694 ◽

2021 ◽

Vol 13 (21) ◽

pp. 3694

Author(s):

Nawaf Labban ◽

Mohammad D. Al Al Amri ◽

Sarah M Alnafaiy ◽

Saleh M. Alhijji ◽

Mohammad A. Alenizy ◽

...

Keyword(s):

Surface Roughness ◽

Mean Value ◽

Control Group ◽

P Value ◽

Distilled Water ◽

Storage Medium ◽

Significant Difference ◽

Toothbrush Abrasion ◽

Surface Gloss

The aim of this study was to compare the surface roughness and gloss of polymer-infiltrated ceramics after simulated in vitro toothbrushing in different storage mediums. Four polymer- infiltrated ceramics were evaluated, Lava ultimate (LU), Vita enamic (EN), Shofu (SH), and Crystal ultra (CU). The control group was a feldspathic ceramic, Vita Mark II (VM). One hundred and twenty specimens (12 × 14 × 2.5 mm) were prepared using a precision saw. For each material (n = 24), the specimens were allocated into two groups, polished and stained. The specimens of each group were stored (for 7 days) in either citric acid (0.2N) or distilled water. Data for surface gloss (ΔE*SCE-SCI) and roughness (Ra) were evaluated before (baseline) and after simulated toothbrushing. For toothbrushing simulation, a toothpaste slurry containing a toothpaste of 100 relative dentin abrasion (RDA) and 0.3 mL distilled water was used for 3650 cycles (7300 strokes) for each specimen. Data were analyzed using t-test and ANOVA. A p-value of ≤ to 0.05 was considered significant. The highest mean value of surface gloss was identified in CU (stained—water) (4.3 (0.47)) (ΔE*) and EN (stained—acid) (4.3 (1.00)) (ΔE*) specimens, whereas the lowest mean value was shown by SH (stained—acid) (2.04 (0.42)) (ΔE*) samples. The highest mean value of surface roughness was observed in SH (0.40 (0.99)) Ra (stained—acid) whereas the lowest in VM (0.13 (0.039)) Ra (polished—water). A significant difference (p < 0.05) was observed in surface roughness and gloss between the materials with simulated toothbrushing, except in VM and LU, respectively. Therefore, it can be concluded that simulated toothbrushing impacts on surface roughness and gloss, irrespective of the storage medium.

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Mechanical Pull-Out Test of a New Hybrid Fixture-Abutment Connection: An In Vitro Study

Materials ◽

10.3390/ma14061555 ◽

2021 ◽

Vol 14 (6) ◽

pp. 1555

Author(s):

Gianmaria D’addazio ◽

Bruna Sinjari ◽

Lorenzo Arcuri ◽

Beatrice Femminella ◽

Giovanna Murmura ◽

...

Keyword(s):

Surface Modification ◽

In Vitro Study ◽

Mean Value ◽

Vitro Study ◽

Test Machine ◽

Pull Out ◽

Significant Difference ◽

Implant Abutment ◽

New Type

Implant abutment connection was described among the main causes of peri-implant bone resorption. The aim of this in vitro study was to test the coupling capacity, the surface modification of a new hybrid connection and the influence of repeated connection activations caused during the main clinical and laboratory phases. A total of 40 implant-abutment screw retained systems with 10°-conical and internal hexagon connection were tested. The connection was screwed, fixed to the universal test machine, removed the screw and a pull-out test was performed. Test was repeated five times in succession. Also Scanning Electron Microscopy (SEM) was used to detect microscopically surface modification. Analysis of variance and Tukey tests were used for the statistical analysis. Pull-out test reveals a mean value of 131.35 ± 16.52 Newton Centimeter (N·cm). For each single activation, results from first to fifth were: 113.9 ± 13.02, 126.1 ± 12.81, 138.11 ± 15.15, 138.8 ± 11.90 and 140 ± 12.99 N·cm. A statistically significant difference between the measurements and an increase in the removal force was shown. The collected data supports the use of this new type of connection, resulting in a very strong interface between implant and abutment. Also, repeated activation of connection can promote a better coupling of the implant-abutment interface.

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Influence of Intra-Oral Scanner (I.O.S.) on The Marginal Accuracy of CAD/CAM Single Crowns

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph16040544 ◽

2019 ◽

Vol 16 (4) ◽

pp. 544 ◽

Cited By ~ 11

Author(s):

Francesco Ferrini ◽

Gianpaolo Sannino ◽

Carlo Chiola ◽

Paolo Capparé ◽

Giorgio Gastaldi ◽

...

Keyword(s):

Standard Deviation ◽

In Vitro Study ◽

Mean Value ◽

Vitro Study ◽

Computer Assisted ◽

Marginal Gap ◽

Significant Difference ◽

Cad Cam ◽

True Definition

The aim of this in vitro study was to compare the quality of digital workflows generated by different scanners (Intra-oral digital scanners (I.O.S.s)) focusing on marginal fit analysis. A customized chrome-cobalt (Cr-Co) implant abutment simulating a maxillary right first molar was fixed in hemi-maxillary stone model and scanned by eight different I.O.S.s: Omnicam® (Denstply Sirona, Verona, Italy) CS3500®, CS3600®, (Carestream Dental, Atlanta, GA, USA), True Definition Scanner® (3M, St. Paul, MN, USA), DWIO® (Dental Wings, Montreal, Quebec, Canada), PlanScan® (Planmeca Oy, Helsinki, Finland), 3D PROGRESS Plus® (MHT, Verona, Italy), TRIOS 3® (3Shape, Copenhagen, Denmark). Nine scans were performed by each tested I.O.S. and 72 copings were designed using a dental computer-assisted-design/computer-assisted-manufacturing (CAD/CAM) software (exocad GmbH, Darmstadt, Germany). According to CAD data, zirconium dioxide (ZrO2) copings were digitally milled (Roland DWX-50, Irvine, CA, USA). Scanning electron microscope (SEM) direct vision allowed for marginal gap measurements in eight points for each specimen. Descriptive analysis was performed using mean, standard deviation, and median, while the Kruskal–Wallis test was performed to determine whether the marginal discrepancies were significantly different between each group (significance level p < 0.05). The overall mean marginal gap value and standard deviation were 53.45 ± 30.52 μm. The minimum mean value (40.04 ± 18.90 μm) was recorded by PlanScan®, then 3D PROGRESS Plus® (40.20 ± 21.91 μm), True Definition Scanner® (40.82 ± 26.19 μm), CS3500® (54.82 ± 28.86 μm) CS3600® (59,67 ± 28.72 μm), Omnicam® (61.57 ± 38.59 μm), DWIO® (62.49 ± 31.54 μm), while the maximum mean value (67.95 ± 30.41 μm) was recorded by TRIOS 3®. The Kruskal–Wallis tests revealed a statistically significant difference (p-value < 0.5) in the mean marginal gaps between copings produced by 3D PROGRESS Plus®, PlanScan, True Definition Scanner, and the other evaluated I.O.S.s. The use of an I.O.S. for digital impressions may be a viable alternative to analog techniques. Although in this in vitro study PlanScan®, 3D PROGRESS Plus® and True Definition Scanner® may have showed the best performances, all I.O.S.s tested could provide clinically encouraging results especially in terms of marginal accuracy, since mean marginal gap values were all within the clinically acceptable threshold of 120 μm.

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Comparison of the Accuracy of Apex Locators with Conventional Techniques in determining the Root Canal Length in Primary Teeth

Journal of Contemporary Dentistry ◽

10.5005/jp-journals-10031-1108 ◽

2015 ◽

Vol 5 (2) ◽

pp. 61-64

Author(s):

Naveen Kumar Kommineni ◽

P Prathyusha Simha ◽

Vinay Chand Reddy ◽

C Lalitha Samyuktha ◽

Prashanth M Battepati

Keyword(s):

Digital Radiography ◽

Root Canal ◽

Primary Teeth ◽

Physiological Saline ◽

Mean Value ◽

Root Canals ◽

Working Length ◽

Significant Difference ◽

Electronic Apex Locator

ABSTRACT Aim To compare the accuracy of apex locators with conventional techniques in determining the root canal length in primary teeth. Materials and Methods This in vitro study was conducted on twenty extracted primary incisors. After endodontic access preparation, root canals were irrigated with physiological saline solution. The access cavities were dried with cotton pellets and, the roots were dried with paper points before performing the electronic measurement. One operator determined the actual working length (AWL) of the canal and another operator measured working length using conventional F-speed radiographs, digital radiography (Dr suni plus digital radiography system, model no 900-0540) and electronic apex locator- Raypex 5 (VDW GmbH Postfach) 5th generation apex locator. The mean value of differences was obtained and statistical analysis was performed using analysis of variance (ANOVA) and the paired t-test. Results There was no statistically significant difference between tooth lengths estimate on conventional, digital and apex locators. 0.5 to 1 mm of clinically acceptable discrepancy was found between three techniques. Conclusion Although there was no significant statistical difference, electronic apex locator (EAL) has more advantage over other techniques, it is considered accurate in determining the working length in primary teeth. How to cite this article Reddy VK, Kommineni NK, Simha PP, Reddy VC, Samyuktha CL, Battepati PM. Comparison of the Accuracy of Apex Locators with Conventional Techniques in determining the Root Canal Length in Primary Teeth. J Contemp Dent 2015;5(2):61-64.

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Zinc Amount in Dental Enamel can be a Potential Factor of Severe Tooth Wear.

10.21203/rs.3.rs-150134/v1 ◽

2021 ◽

Author(s):

Elzbieta Klimuszko ◽

Karolina Orywal ◽

Barbara Mroczko ◽

Teresa Sierpinska

Keyword(s):

Dental Enamel ◽

Tooth Wear ◽

Superficial Layer ◽

Mean Value ◽

Zinc Metabolism ◽

Mean Values ◽

Significant Difference ◽

Potential Factor

Abstract Objective of the study was to assess the potential role of zinc and copper in the process of severe enamel wear. Methods: Three groups of dental enamel samples were analyzed: 50 from subjects with worn dentition, 20 from healthy volunteers in vivo and 15 healthy teeth cut longitudinally into seven layers in vitro. The amounts of Ca, Mg and Zn in the enamel bioptates were established using atomic absorption spectroscopy with an air/acetylene flame after acid biopsy technique had been applied. The concentration of Cu was established using an electrothermic method with argon gas on the AA spectrometer. Results : Mean values of calcium (Ca) and magnesium (Mg) did not differ between all the analyzed specimens. The mean value of zinc amount was very high in the samples obtained from worn teeth comparing to the healthy teeth. Statistically significant difference was confirmed between mean value of zinc amount in severe worn dentition and all the layers in vitro and in vivo. Strong positive relationships between magnesium and zinc contents have been shown at some depths. Significant difference was registered between the amount of copper in the severely worn dentitions compared to the superficial layer of the healthy teeth in vitro and in vivo. Conclusion: It was found that zinc amount was considerably different when comparing worn dentition and healthy teeth. It appears that zinc metabolism may play an important role in enamel formation and may influence the enamel resistance to wear after tooth eruption.

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Comparative Evaluation of Flexural Strength and Flexural Modulus of Different Periodontal Splint Materials: An In Vitro Study

Applied Sciences ◽

10.3390/app9194197 ◽

2019 ◽

Vol 9 (19) ◽

pp. 4197

Author(s):

Shahabe Saquib ◽

AlQarni Abdullah ◽

Das Gotam ◽

Naqash Talib ◽

Sibghatullah Muhammad ◽

...

Keyword(s):

Flexural Strength ◽

Flexural Modulus ◽

In Vitro Study ◽

Mean Value ◽

Vitro Study ◽

Bending Test ◽

P Value ◽

Significant Difference ◽

Different Types

Splinting of the mobile teeth is a critical part of periodontal management to improve the prognosis and longevity of stable results of periodontally compromised teeth with increased mobility. Different types of splints are used in the dental field based on their mechanical and physical properties.The objective of the current in vitro study was to evaluate the flexure strength and flexural modulus of different types of splinting materials, such as: composite block, ligature wire, Ribbond®, InFibra®, and F-splint-Aid® bonded utilizing Flowable composites resin material. Seventy-five bar specimens were prepared with the dimensions of 25 × 4 × 2 mm, utilizing split metallic mold. Specimens were divided equally (n = 15) into five groups (one control group, four test groups). Different layers of splinting material were placed in between the layers of composite before curing. All the specimens were subjected to a three-point bending test by using a universal testing machine to calculate the flexural strength and flexural modulus. The entire data was subjected to statistical tests to evaluate the significance. Specimens from composite block groups showed the least mean value for flexural strength (89.15 ± 9.70 MPa) and flexural modulus (4.310 ± 0.912 GPa). Whereas, the highest mean value for flexural strength (168.04 ± 45.95 MPa) and flexural modulus (5.861 ± 0.501 GPa) were recorded by Ribbond® specimens. Inter group comparison of flexural strength showed statistically significant differences (P-value < 0.05), whereas comparison of flexural modulus showed non-significant difference among the groups (P-value > 0.05). Within the limitation of the present study, it was concluded that the Ribbond® exhibits maximum flexural strength and flexural modulus, whereas the composite blocks recorded the least values. Still, the decision making depends on the clinical scenario and the unique characteristic of each splint material.

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Two-Body Wear of Occlusal Splint Materials Against Different Antagonists

10.21203/rs.3.rs-20886/v1 ◽

2020 ◽

Author(s):

Kubra Yildiz Domanic ◽

Yilmaz Umut Aslan ◽

Yasemin Ozkan

Keyword(s):

Wear Rate ◽

Tooth Enamel ◽

Wear Test ◽

Ceramic Materials ◽

Mean Value ◽

Occlusal Splint ◽

Mean Values ◽

Occlusal Splints ◽

Significant Difference

Abstract Background: This study aimed to demonstrate that the material of the occlusal splint can be chosen according to the needs of individual patients and contribute to the knowledge of the wear rate of these materials.Methods: In this study four occlusal splints materials (Sr Ivocap Heat Cured, Valplast, SR Ivocap Elastomer and Eclipse were selected. As antagonist materials natural tooth enamel, inCoris TZI and IPS e.max Press ceramic materials were used. Each wear test was performed using a chewing simulator (n=16; test load: 50 N; number of cycles: 10,000, 20,000 and 30,000; continuous rinsing with water at 30°C for the wet condition).Results: There was a statistically significant effect of the difference in materials on the amount of wear (p < 0.001). Furthermore, there was a statistically significant difference among the mean values of all materials (p > 0.001). The highest mean value was obtained with Eclipse (0,318 mm3), and the lowest mean value was obtained with Valplast (0,134 mm3).Conclusion: Our study found differences in the in vitro wear rate among various occlusal splint materials.

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