scholarly journals A Repeatable and Reproducible Digital Method to Quantify the Cement Excess and Enamel Loss after Debonding Lingual Multibracket Appliance Therapy

2021 ◽  
Vol 11 (3) ◽  
pp. 1295
Author(s):  
Alba Belanche Monterde ◽  
Alberto Albaladejo Martínez ◽  
Alfonso Alvarado Lorenzo ◽  
Adrián Curto ◽  
Jorge Alonso Pérez-Barquero ◽  
...  

The aim of the present study is to present a repeatable, reproductible, and accurate morphometric measurement method for measuring and quantifying the area and volume of cement that remains after fixed lingual multibracket appliance debonding, enamel loss after fixed lingual multibracket appliance debonding, and the volume of cement used to adhere fixed lingual multibracket appliances. Ten conventional lingual brackets were cemented in 10 extracted teeth embedded into an epoxy resin model simulating a dental arch. This model was scanned before and after bonding the lingual brackets, after debonding, and after polishing the surfaces. We also performed a Micro-Computed Tomography scan of the lingual brackets used. Afterward, the standard tessellation language (STL) digital file was aligned, each tooth was segmented individually, and the file was re-aligned using engineer morphometry software. Inter-operator and intra-operator comparative analyses were performed using the ANOVA test, and the repeatability and reproducibility of the morphometric measurement technique were analyzed using Gage R&R statistical analysis. Repeatability showed 0.07% and 0.16% variability associated with the area and volume measures, respectively, while reproducibility showed 0.00% variability associated with the area and volume measures, respectively. In conclusion, the morphometric measurement technique is a repeatable, reproductible, and accurate morphometric measurement method for quantifying the area and volume of cement that remains after fixed lingual multibracket appliance debonding, enamel loss after fixed lingual multibracket appliance debonding, and the volume of cement used to adhere fixed lingual multibracket appliances.

2021 ◽  
Vol 11 (4) ◽  
pp. 1719
Author(s):  
Alba Belanche Monterde ◽  
Alberto Albaladejo Martínez ◽  
Adrián Curto ◽  
Jorge Alonso Pérez-Barquero ◽  
Clara Guinot-Barona ◽  
...  

The aim of the present study was to compare the area and volume of remaining cement after lingual and buccal multibracket appliance debonding. Further, the area and volume of cement remaining and the area and volume of enamel were also analyzed using a morphometric digital measurement technique. Ten buccal and 10 lingual multibracket appliances were cemented in 20 extracted teeth embedded into an epoxy resin model simulating a dental arch. The models were scanned before bonding the lingual and buccal multibracket appliances, after debonding the lingual and buccal multibracket appliances, and after polishing the remaining cement. Afterwards, the standard tessellation language (STL) digital files were aligned, segmented, and realigned by using engineer morphometry software. A comparative analysis was performed using Student’s t test statistical analysis. Lingual appliances showed statistically significantly (p < 0.001) less area (7.07 ± 4.85 mm2) and volume (0.87 ± 1.34 mm3) of remaining cement than the area (21.99 ± 4.18 mm2) and volume (p = 0.002) (3.48 ± 0.96 mm3) of buccal appliances. Moreover, lingual appliances showed statistically significantly (p = 0.001) less area (4.48 ± 3.08 mm2) and volume (0.13 ± 0.15 mm3) of remaining cement after polishing than the area (12.22 ± 5.98 mm2) and volume (p = 0.004) (0.70 ± 0.56 mm3) of buccal appliances. Lingual multibracket appliance therapy leads to less area and volume of cement remaining after multibracket appliance debonding and less area and volume of cement remaining after cement polishing than buccal multibracket appliance therapy; however, the area and volume of enamel removed after cement polishing were similar between both lingual and buccal multibracket appliance therapies.


2020 ◽  
Vol 9 (4) ◽  
pp. 1098 ◽  
Author(s):  
Álvaro Zubizarreta-Macho ◽  
Martina Triduo ◽  
Jorge Alonso Pérez-Barquero ◽  
Clara Guinot Barona ◽  
Alberto Albaladejo Martínez

The aim of this study was to construct a novel, repeatable, reproducible, and accurate measurement protocol for the area and volume of the remaining cement after removal of fixed multibracket appliances, the area and volume of remaining cement after cement removal, the area and volume of enamel removed after cement removal, and the volume of cement used to adhere fixed multibracket appliances. A total of 30 brackets were cemented and removed with over 30 extracted teeth embedded into three experimental models of epoxy resin. The models were scanned before and after bracket placement, bracket debonding, and polishing the remaining cement. The brackets were submitted to micro-computed tomography. The standard tessellation language digital files were aligned, segmented, and re-aligned using geomorphometric software. The digital measurement technique accuracy, repeatability, and reproducibility were analyzed using Gage R&R statistical analysis. The variability attributable to the area and volume measurement techniques of the total variability of the samples was 0.70% and 0.11% for repeatability, respectively, and 0.79% and 0.01% for reproducibility, respectively. The re-alignment procedure is a repeatable, reproducible, and accurate technique that can be used to measure the area and volume of the remaining cement after removal of fixed multibracket appliances, the area and volume of remaining cement after cement removal, the area and volume of enamel removed after cement removal, and the volume of cement used to adhere the fixed multibracket appliance.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Jae-Young Kim ◽  
Hyo-Won Jang ◽  
Jung-In Kim ◽  
In-Ho Cha

AbstractThe purpose of this study was to investigate the effect of administering intermittent parathyroid hormone (iPTH) before tooth extraction versus after tooth extraction on the risk of developing MRONJ in experimental animal model. Twenty-five ovariectomized rats received 6 weeks of bisphosphonate therapy. They were classified into 3 groups, based on the timing of the medication, as Control, Pre-PTH and Post-PTH groups. For Control group, normal saline was administered before and after tooth extraction. iPTH was administered during 4 weeks before tooth extraction for Pre-PTH group and after tooth extraction for Post-PTH group. The animals were euthanized 8 weeks after tooth extraction. Macroscopic, histological, micro-computed tomography (micro-CT), and histomorphometric examinations were conducted. The incidences of impaired healing were 11.11% both in Pre-PTH and Post-PTH groups, which was lower than the Control group (42.86%). Bone healing in the extraction socket, based on micro-CT and histomorphometry evaluations, was best in Post-PTH and worst in Control group. The Pre-PTH group showed moderate healing pattern. Despite of limitations in this study, the authors identified Pre-PTH group seems to have positive effect on extraction socket healing. With regard to timing, administering iPTH after tooth extraction was superior to applying it before tooth extraction.


2021 ◽  
Author(s):  
Elisabeth C. Barnhart ◽  
Phillip M. Campbell ◽  
Amal Noureldin ◽  
Katie Julien ◽  
Peter H. Buschang

ABSTRACT Objectives To quantify differences in the etch quality of enamel within and between human teeth, which has not previously been attempted. Materials and Methods The buccal right and left halves of 27 extracted human teeth were randomly allocated to scanning electron microscopy (SEM) or micro–computed tomography (μCT) for evaluation. The buccal surfaces were pumiced, etched with 37% phosphoric acid gel etchant for 15 seconds, rinsed, and air dried. Each tooth was divided into three regions (incisal, middle, and cervical) and viewed after etching at 1200× magnification with SEM. The μCT scans were taken before and after etching to calculate apparent and material mineral densities. Results SEM showed greater aprismatic enamel and poorer etch quality (ie, significantly less percentage enamel) for the posterior than anterior teeth and for the cervical region than for the incisal and middle regions of all teeth. Although there were no density differences prior to etching, μCT demonstrated that etching increased material density significantly more for the anterior than posterior teeth. Prior to etching, the enamel in the cervical regions was significantly less dense than the enamel in the middle or incisal regions. Etching significantly increased the material density of all three regions, which decreased initial regional differences. After etching, the apparent density of the cervical region remained significantly lower than the densities of the other two regions. Conclusions Based on SEM and μCT, there is greater aprismatic enamel and inferior etch quality in the cervical regions of all tooth types and is clinically significant in explaining the failure of sealant retention and the propensity for white spot lesions.


PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e5739 ◽  
Author(s):  
Quan-Liang Jian ◽  
Wei-Chun HuangFu ◽  
Yen-Hua Lee ◽  
I-Hsuan Liu

Both age and intensive exercise are generally considered critical risk factors for osteoarthritis. In this work, we intend to establish zebrafish models to assess the role of these two factors on cartilage homeostasis. We designed a swimming device for zebrafish intensive exercise. The body measurements, bone mineral density (BMD) and the histology of spinal cartilages of 4- and 12-month-old zebrafish, as well the 12-month-old zebrafish before and after a 2-week exercise were compared. Our results indicate that both age and exercise affect the body length and body weight, and the micro-computed tomography reveals that both age and exercise affect the spinal BMD. However, quantitative analysis of immunohistochemistry and histochemistry indicate that short-term intensive exercise does not affect the extracellular matrix (ECM) of spinal cartilage. On the other hand, the cartilage ECM significantly grew from 4 to 12 months of age with an increase in total chondrocytes. dUTP nick end labeling staining shows that the percentages of apoptotic cells significantly increase as the zebrafish grows, whereas the BrdU labeling shows that proliferative cells dramatically decrease from 4 to 12 months of age. A 30-day chase of BrdU labeling shows some retention of labeling in cells in 4-month-old spinal cartilage but not in cartilage from 12-month-old zebrafish. Taken together, our results suggest that zebrafish chondrocytes are actively turned over, and indicate that aging is a critical factor that alters cartilage homeostasis. Zebrafish vertebral cartilage may serve as a good model to study the maturation and homeostasis of articular cartilage.


2019 ◽  
Vol 89 (4) ◽  
pp. 535-543 ◽  
Author(s):  
Niko C. Bock ◽  
Julia Ruehl ◽  
Sabine Ruf

ABSTRACT Objective: To assess the prevalence and magnitude of labial gingival recession (LGR) before and after as well as the incidence during Class II:1 Herbst-Multibracket appliance (Herbst-MBA) treatment (Tx) plus retention in a retrospective cohort study. Materials and Methods: Records of Class II:1 patients who completed Herbst-MBA Tx (mean pre-Tx age 14.4 years) at Department of Orthodontics, University of Giessen, Giessen, Germany were analyzed. Tx consisted of a Herbst phase (mean 8.1 months) and a subsequent MBA phase (mean 16.1 months). Study casts from before and after Herbst-MBA Tx plus ≥24 months of retention were evaluated. Results: A total of 460 pre-Tx and 222 postretention study casts were available (total observation period: 59.2 ± 14.8 months). The overall prevalence for teeth with LGR ≥0.5 mm was 1.1% pre-Tx and 5.3% postretention. The highest prevalence of up to 5.3% (pre-Tx) and 16.4% (postretention) were seen for the lower incisors. Overall, the median magnitude of LGR was 0.0 mm pre-Tx/postretention (mean: 0.05 mm/0.08 mm). Incidence values of 4.0% (all teeth) and 10.0% to 11.4% (lower central incisors) were calculated for LGR ≥0.5 mm. Conclusions: The prevalence of LGR ≥0.5 mm increased from, on average, 1.1% to 5.3% during ≈6 years of Herbst-MBA Tx plus retention. The highest incidence was seen in lower incisors (10.0%–11.4%). However, because of the overall mean magnitude of 0.08 mm postretention, the clinical relevance can be considered as insignificant.


2006 ◽  
Vol 45 (02) ◽  
pp. 191-194 ◽  
Author(s):  
E. Tauferová ◽  
Z. Teuberová ◽  
M. Seydlová ◽  
V. Smutný ◽  
J. Racek ◽  
...  

Summary Objectives: The diagnostic procedure commences with the initial examination, during which a number of individual findings of the occlusion or malocclusion are clarified [1]. The objective is to describe the morphological and functional characteristics on each patient using specific guidelines, and then to provide a prognosis of the therapy. Upper and lower arch compression in first premolars and molars area was visible before treatment. Methods: A special device (Czech technical university research prototype) was prepared for this purpose. The optical head contains a digital color camera. The front of the optical head consists of a removable prism which is put into the mouth. The findings can display live images from the camera, which can be archived on a PC. The device captured and geometrically calibrated images permitting comparison of several different dental casts. Results: In the first part of this study 792 sets of study plaster casts were screened. Measurements of dental arch width between reference points of canines, first premolars and first molars were made: upper jaw: men: 3-3 – 35.1 mm (SE 0.13); 4-4 – 37.5 mm (SE 0.13); 6-6 – 48.1 mm (SE 0.19); women: 3-3 – 33.4 mm (SE 0.13); 4-4 – 35.6 mm (SE 0.15); 6-6 – 46.7 mm (SE 0.19). The second part concerns the group of 36 patients which is different from the 792 controls. There were studied changes between initial, post-treatment and post-retention alignment of upper and lower dental arch. Conclusions: Geometrically calibrated images help compare several different steps of the treatment and show a significant difference between patients before and after treatment.


Materials ◽  
2019 ◽  
Vol 12 (24) ◽  
pp. 4196
Author(s):  
Martina Eichenberger ◽  
Anna Iliadi ◽  
Despina Koletsi ◽  
George Eliades ◽  
Carlalberta Verna ◽  
...  

The aim of the present study was to quantitatively assess changes in enamel roughness parameters before and after lingual bracket debonding. The lingual surface of 25 sound premolars extracted for orthodontic reasons was studied by 3D optical interferometric profilometry before and after debonding of lingual brackets following enamel finishing (with fine diamond) and polishing (with 12- and 20-fluted carbide burs). The roughness parameters tested were the amplitude parameters Sa and Sz, the hybrid parameter Sdr, and the functional parameters Sc and Sv. The parameter differences (after debonding-reference) were calculated, and statistical analysis was performed via a Wilcoxon signed-rank test. Statistically significantly higher values were observed in all the surface roughness parameters of enamel surfaces after finishing and polishing, with the mostly affected parameter being the Sdr. Under the conditions of the present study, the finishing and polishing instruments used after debonding of lingual noncustomized brackets created a surface texture rougher than the control in all the tested roughness parameters.


2020 ◽  
Vol 9 (4) ◽  
pp. 1164 ◽  
Author(s):  
Vicente Faus-Matoses ◽  
Cristina Pasarín-Linares ◽  
Ignacio Faus-Matoses ◽  
Federico Foschi ◽  
Salvatore Sauro ◽  
...  

Background: The objective was to evaluate the efficiency of ProTaper Gold (PTG) and Reciproc Blue (RB) NiTi files in obturation material removal from straight root canals assessed by micro-computed tomography. Methods: Fifty-two anterior human teeth were shaped with a PTG rotary system until F2 (25/.08). Specimens were obturated with a continuous wave of condensation technique. For retreatment, specimens were randomly distributed in two experimental groups: PTG group (F4 file) and RB (R40 file). Micro-CT scans were performed before and after retreatment procedures. The percentage of the remaining obturation material compared to the original volume was calculated, as well as the retreatment time. The presence of separated files was recorded. A descriptive analysis was carried out, and nonparametric tests were employed. Results: The mean percentages of remaining obturation material in the PTG group and the RB group were 4.14 ± 4.30% and 4.18 ± 4.29%, respectively. The mean retreatment times for the PTG and RB groups were 144 ± 51 and 163 ± 88 s, respectively. There were no statistically significant differences, neither in removal efficiency (p > 0.05) nor in retreatment time (p > 0.05), between the two groups. The coronal and middle thirds presented significantly more remaining obturation material than the apical third (p < 0.05). No file separation occurred. Conclusions: ProTaper Gold and Reciproc Blue present with comparable efficiency in removing the obturation material, with a similar mean retreatment time.


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