Margin Contour Research Articles

A deviant behaviour of squamous cell carcinoma of eyelid: Rare case report

Squamous cell carcinoma (SCC) is a malignant tumour of the squamous cell layer of the epidermis accounting for about 9.2% of all eyelid malignancies. We report a case of a 45 year old female patient presented with itching, sticky discharge and swelling over the right upper eyelid (RUL) for 20 days. Initially, it was diagnosed as a case of blepharitis of Right Eye and antibiotic eye ointment and lubricants were prescribed. And 2 months later she presented with a mass over the same site. Past history of trauma, burn and chronic exposure to sunlight was absent. Examination revealed a mass of 1.25cm -1.50cm width & 1cm - 1.25cm in height approximately, shape was irregular & firm in consistency. Eyelid margin contour was lost with loss of eyelashes. Other ocular structures were within normal limits. No associated lymphadenopathy was noted. Incisional biopsy of the mass was suggestive of moderately differentiated SCC. Wide excision of the mass was done. Full thickness defect of the upper eyelid was reconstructed with Cutler - Beard technique. : Wide variation at presentation, delay in diagnosis and high propensity to recur with risk of perineural spread leads to difficulty in management. Therefore, any suspicious lesion eyelid lesion should be excised and biopsied.

Analysis of root coverage esthetic score in patients treated for gingival recession: An interexaminer reliability.

Background:Awareness about pink esthetics among dentists in general needs to be assessed as root coverage procedures are the mainstay of treatment for gingival recession. Concordance among the dentists in figuring out the esthetic outcomes after root coverage procedures is inconsistent. Hence, this study aims to evaluate inter- and intra-examiner reliability of root coverage esthetic scores (RES) between periodontists and nonperiodontists.Materials and Methods:The study was conducted using twenty baseline and 6-month posttreatment photographs of Miller's Class I and Class II gingival recessions. The participants that constituted ten periodontists and ten nonperiodontists were assembled in the seminar hall to receive training on protocol and procedures for RES by the investigator. All the participants were shown twenty projections of side-by-side baseline and 6-month outcomes of root coverage procedures. Each projection was shown for 30 s during which the participants were made to use RES system to evaluate the surgical outcomes.Results:Periodontists showed the highest reliability in the scores of marginal tissue contour with an overall intraexaminer reliability to be perfect among periodontists. Intraexaminer reliability among nonperiodontists was fair, and gingival margin was the parameter with the highest reliability among them. Interexaminer reliability between periodontists and nonperiodontists showed slight reliability concerning gingival margin, and fair reliability was found for marginal tissue contour, soft-tissue texture, mucogingival junction, and gingival color.Conclusion:Satisfying the esthetic component of gingiva is the duty of every dentist in general and not only the periodontists. Significant variability was found in esthetic scores between the groups, which can probably be attributed to the lack of sufficient knowledge regarding pink esthetics among the nonperiodontists, which needs to be improved.

Four-dimensional carbon-ion pencil beam treatment planning comparison between robust optimization and range-adapted internal target volume for respiratory-gated liver and lung treatment.

We investigated the dose differences between robust optimization-based treatment planning (4DRO) and range-adapted internal target volume (rITV). We used 4DCT dataset of 20 lung cancer and 20 liver cancer patients, respectively, who had been treated with respiratory-gated carbon-ion pencil beam scanning therapy. 4DRO and rITV plans were created with the same clinical target volume (CTV) and organs at risk (OAR) contours. Four-dimensional dose distribution was calculated using deformable image registration. Dose metrics (e.g. D95, V20) were analyzed. Statistical significance was assessed by the Wilcoxon signed-rank test. For the lung cases, the mean CTV-D95 value for the rITV plan (=98.5%) was same as that for the 4DRO plan (=98.5%, P=0.106), while the mean D95 value for the CTV+setup margin contour for the rITV plan (=98.2%) was higher than that for the 4DRO plan (95.2%, P<0.001). For the liver cases, the mean CTV-D95 value for the rITV plan (=98.1%) was slightly lower than that for the 4DRO plan (=98.5%, P<0.01), while the mean D95 value for the CTV+setup margin contour for the rITV plan (=98.0%) was higher than that for the 4DRO plan (94.1%, P<0.001). For the doses to the organs at risk (OARs), the ipsilateral lung-V20/liver-V20 values for the rITV plan (=10.1%/19.7%) was significantly higher than that for the 4DRO plan (=8.6%/17.6, P<0.001). Although the target coverage for 4DRO plan may be worse than that for rITV plan in the presence of the setup error, the 4DRO plan can improve OAR dose while preserving acceptable target dose coverage.

Coronally advanced flap achieved higher esthetic outcomes without a connective tissue graft for the treatment of single gingival recessions: a 4-year randomized clinical trial.

Limited long-term data are available when comparing the esthetic outcomes of coronally advanced flap (CAF) with or without a connective tissue graft (CTG). The aim of this study was to compare the 4-year esthetic outcomes of CAF vs CAF + CTG for the treatment of isolated maxillary gingival recessions. Forty-eight patients were randomly assigned for treatment either with CAF (control; N = 24) or to CAF + CTG (test group; N = 24). Patients were followed after the surgery until the final evaluation. A professional esthetic evaluation was performed using the Root coverage Esthetic Score (RES). Recession reduction, mean root coverage, and complete root coverage were also evaluated. Forty-two patients completed the study at the 4-year recall. A significant recession reduction was evident at 4 years, without significant intergroup differences. The CAF group showed a statistically significant higher final RES compared with the CAF + CTG group (9.14 ± 1.08 vs 7.25 ± 1.29, respectively, p < 0.001). Regarding the individual components of RES, gingival margin and marginal tissue contour were significantly higher in the CAF group compared with that in the CAF + CTG group. CAF presented with a significantly higher overall esthetic score than CAF + CTG, and in the individual RES components of marginal tissue contour and gingival margin after 4 years. CAF without the addition of CTG provided higher esthetic outcomes for the treatment of isolated gingival recessions.

Porcine dermal matrix sandwich graft for lower eyelid reconstruction

ABSTRACT Purpose: To report the clinical outcomes of porcine acellular dermal matrix implants sandwiched between skin and conjunctival flaps for lower eyelid reconstruction following Mohs surgery. Methods: A retrospective review was performed on patients with lower eyelid defects following Mohs surgery treated using a porcine acellular dermal matrix sandwich graft from 2013 to 2018. Patient demographics, defect size and characteristics, and collagen matrix implant dimensions were evaluated. Postoperative course and complications were also reviewed. Results: The dermal matrix sandwich graft was performed in 13 cases (12 patients). Average horizontal marginal defect width was 11.7 mm (range: 6–16 mm). Mean width of the implanted dermal matrix was 7.7 mm (range: 5–9 mm). There were no instances of infection or graft failure. The reconstructed lid had an excellent marginal contour in 11 cases (84.6%), while 2 had minimal irregularities. All patients had an excellent thickness of the reconstructed margin. One patient (7.7%) required cauterization of overgrown marginal conjunctiva after surgery. Two patients (15.4%) experienced symptomatic trichiasis, requiring electrolysis (n = 1) and epilation (n = 1). Conclusions: The dermal matrix sandwich graft is an effective method for marginal defect repair when the remaining conjunctiva and skin are sufficient to develop the necessary flaps. While the resolution of edema and erythema may take several months, an excellent final result is achieved in the majority of cases. Complications are mild, relatively uncommon, and similar to those encountered in other reconstructive procedures. This single-stage, tissue-sparing technique preserves the capability of performing future tarsoconjunctival flaps or lateral canthal procedures, should the need arise.

Immediate implant placement and provisionalization: Aesthetic outcome 1 year after implant placement. A prospective clinical multicenter study.

Prospective aesthetic outcomes on a high number of patients after immediate implant placement and provisionalization (IIPP) are lacking. To analyze the aesthetic outcome after IIPP. One hundred consecutive patients with a failing maxillary incisor were provided with an immediately placed and provisionalized nonloaded implant using a flapless procedure and palatal implant positioning. The remaining gap buccally was filled with a bone substitute. Preoperatively (T0), 2 weeks postoperatively (T1), direct after placement of the permanent crown (T2), and 1 year after IIPP (T3), standardized light photographs were made. Change in aesthetic score was the primary outcome measure. Both the white aesthetic score (WES) and pink aesthetic score (PES) were used. In the first year postsurgery, the mean total-WES and total-PES scores raised from 4.5 to 8.2, and from 9.9 to 12.1, respectively. The mean PES scores for mesial and distal papilla, soft tissue marginal level, contour, color, and texture, raised significantly (P < .05), while the alveolar process contour, on average, remained stable from T0 to T3. Within the limitations of this 1-year research, it may be concluded that, following this minimal invasive IIPP procedure, a high aesthetic outcome was achieved.

Comparative geochemical study of the cherty rocks of the Taukha terrane (Sikhote-Alin) and its paleogeodynamic significance

The article presents the results of a comparative geochemical study of cherts and siliceous–clayey rocks composing the tectono-sedimentary complexes of various structural levels of the Taukha terrain of the Sikhote-Alin Late Jurassic–Early Cretaceous accretionary prism. The data obtained show that the same-aged parts of the cross-sections of the cherty–terrigenous sequences of the terrane lower and middle structural levels are characterized by significantly different contents and distribution patterns of major petrogenic oxides, trace, and rare-earth elements due to their accumulation in various facies of oceanic zones. The set of geochemical data indicates that the formation of both tectono-sedimentary complexes was carried out differently, gradually replacing each others’ facies oceanic zones, and started in the near-spreading ridge area, then in the pelagial, and completed in the continental-margin deposition environment. Based on the time interval of the facies conditions changing for each complex (i.e., time of transition from one facies zone to another), the speeds of a paleo-oceanic plate motion (and, correspondingly, the speeds of spreading) for individual intervals of the Jurassic were calculated. Differences in the spreading speeds at various sites of a paleorift zone caused the turning of a paleocontinent margin contour and spreading ridge axis at the perpendicular position, which in turn caused change of the geodynamic mode on the eastern margin of the Paleo-Asian continent at the Jurassic–Cretaceous transition.

ГЕОМЕХАНИЧЕСКАЯ ОЦЕНКА ПАРАМЕТРОВ УСТОЙЧИВОСТИ ОТКОСОВ БОРТОВ И УСТУПОВ ПРИ ОТРАБОТКЕ МЕСТОРОЖДЕНИЯ АПАТИТ-НЕФЕЛИНОВЫХ РУД «ОЛЕНИЙ РУЧЕЙ»

Актуальность обусловлена необходимостью безопасного ведения горных работ на карьерах глубиной свыше 360м. Наращивание объёмов добычи возможно при значительном углублении; для снижения объёмов вскрыши необходимо укручение откосов бортов и уступов. Для решения данного вопроса необходимо знать геомеханическую обстановку уступов и бортов как на предельном контуре, так и при изменении их основных параметров – высоты и углов наклона. Цель: проанализировать горно-геологические условия месторождения «Олений ручей» и существующие данные о физико-механических свойствах горных пород, слагающих массив рассматриваемого месторождения, произвести расчет и проверку устойчивости откосов бортов карьера на предельном контуре и изыскать возможность укручения откосов бортов и вскрышных уступов при ведении горных работ. Объект: крупное месторождение апатит-нефелиновых руд «Олений ручей». Методы: горно-геологический анализ месторождения «Олений ручей» и анализ существующих данных о физико-механических свойствах горных пород, слагающих массив рассматриваемого месторождения, аналитические расчеты устойчивости элементов откосов. Результаты. Получены данные расчетов устойчивости откосов при отсутствии поверхностей ослабления в прибортовом массиве борта в висячем боку рудной залежи (висячий борт) и с учетом угла падения Главного разлома под углом 40–45° при формировании борта в лежачем боку (лежачий борт), а также с учетом сейсмичности района и уровня грунтовых вод. Определены параметры откосов бортов на предельном контуре. Полученные значения параметров правомерны при отсутствии в прибортовом массиве поверхностей ослабления. При наличии поверхностей ослабления с падением в выработку откосы необходимо заоткашивать строго по этим поверхностям.

Aesthetic assessment after root coverage of multiple adjacent recessions with coronally advanced flap with adjunctive collagen matrix or connective tissue graft: Randomized clinical trial.

Few studies have looked at professional assessment or patient perception of aesthetics after root coverage procedures. The addition of connective tissue grafts (CTG) seems to improve aesthetic outcomes. The objective of this a priori analysis was to compare aesthetics after addition of CTG or a collagen matrix (CMX) to coronally advanced flap (CAF). Two independent, trained and calibrated assessors analysed baseline and 6-month post-operative Images from 183 subjects with 475 recessions from a previously reported multicentre multinational randomized clinical trial. Theroot coverage aesthetic score (RES) was assessed in its five constituent components after assessing the suitability of images blindly with regard to treatment assignment and centre. Data were analysed at the tooth and subject level. One hundred and fifty-five subjects (81 CTG) and 393 teeth (207 CTG) were included in the analysis. CTG control subjects had higher total RES scores (mean adjusted difference of 1.3±0.8 RES units, p=0.002). Analyses of RES subcomponents showed that the CTG group had higher scores in terms of gingival margin position but that better marginal tissue contour (OR 3.0, 95% CI 1.2-7.7) and soft tissue texture (OR 3.3, 95% CI 1.9-5.8) was observed for the CMX group. No significant differences were observed for mucogingival alignment and gingival colour. Better overall RES scores were observed for the CTG group. Better marginal tissue texture and marginal contour were observed in the CMX group. More research and development is needed to optimize materials to be used in conjunction with CAF to improve root coverage without negatively affecting tissue texture and marginal contour.

Reconstruction of Upper Eyelid Defects Secondary to Malignant Tumors with a Newly Modified Cutler-Beard Technique with Tarsoconjunctival Graft

Purpose We describe a modification of Cutler-Beard's technique, using a contralateral tarsoconjunctival graft, in patients who underwent excision of large malignant tumors of the upper eyelid. Methods This is an interventional retrospective review (clinical study) of ten cases, with age range from 64 to 86 years (mean: 71.2 years ± 6.49) with malignant upper eyelid tumors, operated by the same surgeon (AB-G), between 2011 and 2016. The resulting defects were reconstructed using a modification of Cutler-Beard's technique. A tarsoconjunctival graft was harvested from the contralateral upper eyelid, with an extra 3 mm of conjunctiva from the superior edge of tarsus and was attached to the upper eyelid defect, different from that previously described. Follow-up ranged between 24 and 60 months (mean: 41.6 ± 9.87). Functional, cosmetic outcomes and postoperative complications were evaluated. Results No upper eyelid retraction, eyelid margin entropion, or graft retraction was observed in any of the cases. All of the patients were satisfied with the aesthetic result. Conclusion This technique allows us to safely inset a suitable graft on the ocular surface, with sufficient blood supply, resulting in a stable margin and good contour.

Treatment of single maxillary gingival recession associated with non-carious cervical lesion: Randomized clinical trial comparing connective tissue graft alone to graft plus partial restoration.

Gingival recession (GR) is frequently associated with non-carious cervical lesion (NCCL) forming a combined defect (CD). The aim of this study was to evaluate a new multidisciplinary protocol for CDs. Forty patients presenting 40 Miller's Class I or II GR defects associated with B+ tooth cervical defect were randomly allocated to one of the following treatments: test group (n=20), partial restoration (PR) of the NCCL, in which the apical border of the restoration was placed 1mm beyond the cement-enamel junction estimation, and connective tissue graft (CTG+PR) and Control Group (n=20), odontoplasty of the NCCL and connective tissue graft (CTG). Clinical, aesthetic and patient-centred outcomes were evaluated. After 12months, CD coverage rates were 75.3% (2.5±1.0mm) for CTG+PR and 74.6% (2.4±1.1mm) for CTG (p>0.05). The estimated complete root coverage was 60% (n=12) for CTG+PR and 70% (n=14) for CTG. CTG+PR resulted in significantly better dentin hypersensitivity (DH) reduction (p=0.034). Both groups resulted in aesthetic improvements; however, the CTG+PR group showed better gingival contour results. CTG and CTG+PR were effective to treat CD. Use of PR resulted in better gingival margin contour and DH reduction, without effect on CD coverage by CTG. (NCT02817763).

Evaluation of the Adhesion of a Novel Design of Veneers to Dental Materials

The aim of this in vitro study was to assess a new design that, to our knowledge, we have introduced (patent pending) for indirect dental veneers. Their effect on the retention and adhesive properties at their interfaces have been studied. Fourteen high performance polymeric (PEEK) dental veneers have been elaborated using a computer-aided-design (CAD) software and then milled using a computer-aided-machine (CAM). They were divided in two experimental groups: seven classical veneers with a liniar marginal contour and seven dental veneers with the novel proposed sinusoidal marginal design. All the samples have been bonded to polymeric blocks that had the vestibular face prepared in a specific way for each group. The values of the retention and adhesive forces were tested in vitro by applying bending forces on the incisal edge of the veneers, from the oral to the vestibular direction. A 50% increase of the values of these forces for the novel design with regard to the classical one has been demonstrated through the study.

Lower Eyelid Reconstruction with Combined Sliding Tarsal and Rhomboid Skin Flaps.

To report results in patients undergoing lower eyelid reconstruction following Mohs surgery using a combination of surgical techniques, the rhomboid skin flap and a sliding tarsal flap. An IRB approved, retrospective case series of patients undergoing surgery between April 2007 and October 2014. Outcomes include establishment of a functional eyelid, quality of postoperative eyelid margin contour, and postoperative complications. During the study period, sliding tarsal flaps were used to repair marginal lower eyelid defects in 32 patients. Coexisting anterior lamellar defects were repaired with a modified rhomboid skin flap in 24 patients, a full thickness skin graft in 4 patients, and combined skin graft and rhomboid flaps in 4 patients. The average width of the marginal defects was 11.3 mm (range: 7-19 mm). Reconstruction resulted in a functional lower eyelid in all patients, the majority having an excellent cosmetic result (n = 20). Minimal contour abnormalities were present in 9 patients, while 3 patients developed a noticeable notch following surgery. Patients repaired with a rhomboid flap were more likely to have isolated postoperative misdirected lashes (5/24) than those repaired using a skin graft with or without a flap (0/8). Combined sliding tarsal and modified rhomboid skin flaps are an effective method of repairing superficial defects of the lower eyelid margin. This tissue-preserving technique maintains the ability to perform subsequent upper eyelid tarsoconjunctival flaps and lateral canthal procedures should a future need arise. Isolated misdirected lashes and minor contour abnormalities are the most common complications of the procedure.

Gaussianization for fast and accurate inference from cosmological data

We present a method to transform multivariate unimodal non-Gaussian posterior probability densities into approximately Gaussian ones via non-linear mappings, such as Box--Cox transformations and generalisations thereof. This permits an analytical reconstruction of the posterior from a point sample, like a Markov chain, and simplifies the subsequent joint analysis with other experiments. This way, a multivariate posterior density can be reported efficiently, by compressing the information contained in MCMC samples. Further, the model evidence integral (i.e. the marginal likelihood) can be computed analytically. This method is analogous to the search for normal parameters in the cosmic microwave background, but is more general. The search for the optimally Gaussianising transformation is performed computationally through a maximum-likelihood formalism; its quality can be judged by how well the credible regions of the posterior are reproduced. We demonstrate that our method outperforms kernel density estimates in this objective. Further, we select marginal posterior samples from Planck data with several distinct strongly non-Gaussian features, and verify the reproduction of the marginal contours. To demonstrate evidence computation, we Gaussianise the joint distribution of data from weak lensing and baryon acoustic oscillations (BAO), for different cosmological models, and find a preference for flat $\Lambda$CDM. Comparing to values computed with the Savage-Dickey density ratio, and Population Monte Carlo, we find good agreement of our method within the spread of the other two.

One-Stage Alternatives to the Hughes Procedure for Reconstruction of Large Lower Eyelid Defects: Surgical Techniques and Outcomes.

To present the results of 1-stage surgical advancement flaps for the repair of large full thickness lower eyelid defects. These avoid the disadvantages of the 2-stage Hughes procedure and provide favorable functional and aesthetic outcomes. A retrospective case series of 36 lower eyelid repairs performed on 31 patients by a single surgeon in Sydney, Australia is presented. The selection criterion was a horizontal defect size 10 mm or greater that could have "classically" been repaired with a 2-stage Hughes procedure. Three different 1-stage surgical repair techniques were utilized, all incorporating local advancement-type flaps: 1) a lateral-based full thickness advancement flap; 2) a vertical tarsal plate advancement flap combined with a full thickness skin graft; and 3) a vertical skin advancement flap combined with a mucosal graft. The postoperative outcomes evaluated included flap viability, lower eyelid margin position and contour, characteristics of the new eyelid margin and patient satisfaction. Thirty-six lower eyelid repairs were performed in 31 patients. There were no cases of flap ischemia, necrosis, or failure. There was 1 case (3%) of postoperative eyelid retraction, 1 case (3%) of eyelid entropion requiring surgical repair, 1 case (3%) of pyogenic granuloma, 2 cases (6%) of eyelid margin cyst, and 7 cases (19%) of eyelid distichiasis. In 34 cases (94%), the patient was satisfied with the aesthetic result. The techniques described provide successful alternatives to the Hughes procedure. They are 1-stage and do not render the patient temporarily monocular, or alter the upper eyelid anatomy or function. All maintained favorable long-term functional and aesthetic outcomes for the reconstructed lower eyelid.

Evaluation of Bony Anatomy versus Endobiliary Stents as Surrogates for Volumetric Image Guidance in Pancreatic Cancer

Online treatment setup verification through cone-beam computed tomography (CBCT) in pancreatic cancer patients is limited by low soft-tissue contrast. Current practice at our institution relies on targeting bony anatomy as a surrogate for treatment setup verification; however studies suggest the pancreas is a mobile organ and its location is not predictable in correlation with the bony anatomy in 80% of fractions. Endobiliary stents are implanted within patients with palliative intents, relieving symptoms (jaundice) of biliary strictures caused by the gross disease. This study aims to quantify the relative positional displacements between bony anatomy and endobiliary stents, and determine the suitability of both surrogates for pancreatic cancers. Eighteen sequential pancreas patients treated at our institution between 2013 and 2015 with endobiliary stents were identified in this ethics approved study. Daily CBCT images were retrospectively examined to compare the location of the stent and bony anatomy relative to the target mass. Using a shaped region of interest, automatic translational (T) and rotational (R) displacements of the stent were quantified. Similarly, using a defined region of interest, automatic bony anatomy image registration was performed to quantify T and R displacements. After initial image registration with either the stent or bony anatomy, to evaluate the suitability of surrogate used, the position of the pancreatic target within the planning target volume (PTV) margin contour was assessed for coverage. Results Pending.

Conjunctiva-Sparing Posterior Ptosis Surgery: A Novel Approach.

Müller's muscle conjunctiva resection is a well-established means of correcting blepharoptosis. The primary objective of this prospective study was to determine if modifying Müller's muscle conjunctiva resection by sparing the conjunctiva would accomplish successful repair while allowing patients to retain their conjunctiva. The potential advantages of preserving conjunctiva are significant and include: conservation of an anatomically normal tissue, retention of goblet cells, reduction of suture-related complications such as corneal irritation or abrasion as the conjunctiva covers the suture during postoperative healing, and preservation of conjunctiva for potential future surgical procedures critical to ocular health. This is a prospective study enrolling patients with mild to moderate ptosis. The procedure has been performed in 18 patients and 30 eyelids. Follow up at 1 week revealed normal healing with expected postoperative edema and ecchymosis. Notably, all patients were free of any corneal abrasion or irritation. Follow up at 1 month and a minimum of 3 months (average 5.7 months) revealed that all patients had satisfactory correction of their blepharoptosis with Margin Reflex Distance 1 (MRD1) improvement to within 1 mm of the anticipated goal, preserved eyelid margin contour, and good symmetry (average 0.26 mm difference in MRD1 between the sides). These results show an effective correction of blepharoptosis with a favorable cosmetic outcome and low postoperative complication rate; all while preserving the conjunctiva.

Identifying ultrasound and clinical features of breast cancer molecular subtypes by ensemble decision.

Breast cancer is molecularly heterogeneous and categorized into four molecular subtypes: Luminal-A, Luminal-B, HER2-amplified and Triple-negative. In this study, we aimed to apply an ensemble decision approach to identify the ultrasound and clinical features related to the molecular subtypes. We collected ultrasound and clinical features from 1,000 breast cancer patients and performed immunohistochemistry on these samples. We used the ensemble decision approach to select unique features and to construct decision models. The decision model for Luminal-A subtype was constructed based on the presence of an echogenic halo and post-acoustic shadowing or indifference. The decision model for Luminal-B subtype was constructed based on the absence of an echogenic halo and vascularity. The decision model for HER2-amplified subtype was constructed based on the presence of post-acoustic enhancement, calcification, vascularity and advanced age. The model for Triple-negative subtype followed two rules. One was based on irregular shape, lobulate margin contour, the absence of calcification and hypovascularity, whereas the other was based on oval shape, hypovascularity and micro-lobulate margin contour. The accuracies of the models were 83.8%, 77.4%, 87.9% and 92.7%, respectively. We identified specific features of each molecular subtype and expanded the scope of ultrasound for making diagnoses using these decision models.

Platinum segments: a new platinum chain for adjustable upper eyelid loading

PurposeProspective study evaluating outcomes of individually sutured platinum segment chains in upper eyelid loading.MethodsSingle-centre, single-surgeon, prospective study. Upper eyelid loading with 0.4 and 0.2 g platinum segment chains for lagophthalmos....

Influence of implant angulation on the fracture resistance of zirconia abutments.

To investigate the effects of abutment design to correct for implant angulation and aging on the fracture resistance of zirconia abutments. Greater understanding of the fracture strength of the zirconia abutments under various clinical conditions may lead to improvement of clinical protocols and possibly limit potential failures of implant prosthetics. Test specimens consisted of an implant-zirconia abutment-zirconia crown assembly with implant apex positioned at 0°, 20° to the facial (20F), and 20° to the lingual (20L) with respect to a constant crown contour. To keep the abutment design as the only variable, CAD/CAM technology was used to generate monolithic zirconia crowns identical both in external and internal dimensions and marginal contours to precisely fit all the abutments in an identical fashion. The monolithic zirconia abutments were designed to fit the constant crown contours and the internal connection of the implant at the three angulations. The customized abutments for the three implant angulations varied in emergence profile, screw hole location, and material thickness around the screw hole. Half the specimens from each group were subjected to steam autoclaving and thermocycling to simulate aging of the restorations in vivo. To mimic the off-axis loading of the central incisor, the specimens were loaded at the recommended cephalometric interincisal relationship of 135° between the long axis of the crown supported by the implant and the Instron force applicator simulating the mandibular incisor. The force applicator was positioned 2 mm from the incisal edge and loaded at a 1 mm/min crosshead speed. Data were evaluated by 2-way ANOVA (α = 0.05) and Tukey's HSD. The 20F group had the highest fracture values followed by the 0° group, and the 20L group had the lowest fracture values. Aging did not yield any significant difference in fracture force magnitudes. Within the limitations of this study, tilting the implant apex to the lingual significantly reduced the fracture strength of angle-corrected zirconia abutments. Accordingly, while the angle between the occlusal force application and the long axis of the implant decreases, the resistance (force) to fracture decreases.