Three-dimensional evaluation of treatment results of the Alt-RAMEC and facemask protocol in growing patients

PURPOSE

The aim of this retrospective study was to evaluate the skeletal, dental, and soft tissue effects of the alternating rapid maxillary expansions and constrictions (Alt-RAMEC) protocol combined with a facemask in prepubertal patients.

METHODS

The study group (mean age 9.74 ± 1.46 years) consisted of 20 patients with class III malocclusion characterized by maxillary retrognathism. They were treated with a facemask for 7 months following a 9‑week Alt-RAMEC protocol. Cone-beam computed tomography (CBCT) records and three-dimensional (3D) photographs taken before (T0) and after the protraction and retention period (T1) were evaluated. The study group was compared with a well-matched control group of 16 untreated patients (mean age 9.44 ± 0.79 years) with the same malocclusion. The records for the control group included cephalometric radiographs and 3D photographs.

RESULTS

In the study group, significant forward movements of A point (3.49 mm), nasal (2.91 mm) and zygomatic bones were achieved. Intermolar, internasal, and interzygomatic widths increased. Soft tissue points followed the hard tissue movements, apart from b and pog. In the control group, A (0.97 mm), B (1.69 mm), Pog, and b points presented forward movement. Significant differences were found regarding the forward movement of the maxilla between the groups.

CONCLUSION

The Alt-RAMEC/facemask protocol was effective not only in the maxillary region but also in the midface.

Use of a new skin colour measurement method for the investigation of relationship between skin and tooth colour

Purpose

There is conflicting information about the relationship between tooth color and skin color in the literature. The aim of the present study was evaluation of the correlation between L, a, b values of skin and tooth shade using a new skin color measurement method.

Materials and methods

CIELab values of teeth were obtained through measurements from the middle third of the labial surfaces on central incisors of individuals using a clinical spectrophotometer. CIELab values of the skin were measured through facial images using a software which was manufactured for present study. A statistical analysis program (SAS 9.4) was used for the analysis of the data. Kolmogorov-Smirnow test, t-test, and multivariate regression analysis were used to evaluate the data (α=0.05).

Results

Correlations between variables revealed that while the lowest and statistically insignificant correlations were observed with a* values of the skin, significant correlations did not exceed moderate level (p < .05). When considering regression analysis results, b* values of the skin had a statistically significant effect in describing b* values of the tooth, while L* and a* values of the skin were observed to be insufficient in describing L* and a* values of the teeth.

Conclusion

Results of this study suggest that different significant correlations were observed between the skin and tooth color for different L*, a*, and b parameters (p <0.05 and p <0.01). The results indicated that skin color can be used for tooth color selection in case of loss of natural teeth or when discoloration is present on existing teeth.

Comparison of clinical and magnetic resonance imagining data of patients with temporomandibular disorders

Background

There are important criteria in the diagnosis of temporomandibular disorders (TMDs). These become significant if supported by magnetic resonance imaging (MRI). Otherwise, these findings alone may not be sufficient to diagnose TMD.

Aim

This study compared the relationship between clinical findings indicated by patient and physician and MRI results in the diagnosis of TMD.

Materials and Methods

Clinical examinations were performed in patients suspected of TMD for pain, difficulty in mouth opening, masticatory muscle tenderness, deviation (during mouth opening), normal mouth opening, and presence of bruxism. The MRI findings of the patients were compared with the clinical examinations.

Results

MRI and clinical examination data of 136 patients were examined. The results showed significant correlations between deviation, normal mouth opening, and MRI results of TMD (P < 0.05). No correlation was found between age groups and clinical findings of TMD. TMJ was determined in normal limits in 61% of MRI results.

Conclusions

Except for deviation and normal mouth opening, complaints and clinical findings determined by the clinicians do not support TMD. This may be due to the subjective nature of the clinical findings, and MRI results are needed for precise results.

Investigation of the Optimal Interval for Staged Total Knee Arthroplasty for the Treatment of Advanced Bilateral Gonarthrosis

PURPOSE OF THE STUDY This study investigated whether there was an optimal interval between two operations for total knee arthroplasties in patients with advanced bilateral gonarthrosis scheduled to undergo staged total knee arthroplasty (TKA). MATERIAL AND METHODS A prospective cohort of 219 patients (136 females, 83 males) undergoing staged total knee arthroplasty for the treatment of advanced bilateral gonarthrosis were followed for up to 12 months. The mean was 69.51±5.02 (56-80) years. Patients were categorized into five groups based on the time between the first and second operations; Group I (21-90 days), Group II (91-180 days), Group III (181-270 days), Group IV (271-360 days), and Group V (more than 360 days). Patients were evaluated based on time from surgery and were assigned to corresponding groups. The data recorded included age, body mass index (BMI), side of operated knee, complications, and radiological and clinical findings. Visual analog scale (VAS) for non-operated knees was applied. Activities of Daily Living Score (ADLS) was applied to the patients at last follow-up. RESULTS No statistically significant difference was noted in BMI values (p=0.634), range of joint motion (RJM) (p=0.940) and age (p=0.785) distribution between the five groups. In Group I, the mean VAS score increased by 7.83 to 7.98, 7.86 to 8.53 in Group II, by 7.85 to 8.54 in Group III, 7.85 to 8.59 in Group IV, and 7.88 to 8.64 in Group V. There was no statistically significant difference in preoperative ADLS between the groups (p=0.064), but there was a statistically significant difference in postoperative ADLS (p=0.001). Group I patients had significantly lower postoperative ADLS compared to the other groups (p=0.001). The mean increase in postoperative ADLS versus preoperative scores of all groups were statistically significant The most significant improvements occurred in Groups II and III. Similarly, preexisting pain in the non-operated knee started to increase in Group II and continued in all groups. DISCUSSION Given all these findings, we believe that it is reasonable to advise patients to receive their second TKA, 3-6 months after their initial TKA, as this interval will allow for the greatest improvements in functional and daily living activities, and pain in the non-operated knee simultaneously becomes more severe. This recommended interval would minimize both the functional problems with the operated extremity due to pain, and deformity and dysfunction in the non-operated knee and the subsequent overloading. CONCLUSIONS Even though a number of factors influence the optimal interval for staged TKAs in bilateral gonarthrosis, an interval of 91-270 days appears to be the optimal interval between surgeries in terms of minimizing pain and maximizing ADL s and knee scores. Key words: bilateral total knee arthroplasty, optimal interval, knee society scores, activities of daily living.

Use of an attachment system with angulated abutments and polyetheretherketone inserts to retain a maxillary overdenture: A clinical report

This clinical report describes the rehabilitation of a maxillary edentulous arch with a current overdenture attachment system with angulated prefabricated abutments and polyetheretherketone (PEEK) inserts. Prefabricated angulated abutments were used on previously and recently placed diverging implants, which enabled a common path of insertion for the overdenture to be established during fabrication.

Marginal fit of CAD-CAM monolithic zirconia crowns fabricated by using cone beam computed tomography scans

STATEMENT OF PROBLEM

Information regarding the precision of monolithic zirconia crowns fabricated by using a standard computer-aided design and computer-aided manufacturing (CAD-CAM) workflow is available. However, information on the effect of a modified workflow using 3D laboratory scanning and/or cone beam computed tomography (CBCT) for monolithic zirconia crown fabrication is lacking.

PURPOSE

The purpose of this in vitro study was to evaluate the effect of different scans on the marginal fit of CAD-CAM monolithic zirconia crowns fabricated by 3D laboratory scanning and CBCT.

MATERIAL AND METHODS

An extracted maxillary left first molar was prepared and digitized by using a 3D laboratory scanner (D900; 3Shape A/S) (control group). The tooth was also scanned by CBCT (i-CAT; Imaging Sciences) to generate a second virtual 3D model (CBCTscan group). A tooth cast out of polyurethane (PU) (Zenotec Model; Wieland) was reproduced from the CBCT data by using a CAD software program (Dental System 2.6; 3Shape A/S) and milling machine (CORiTEC 550i; imes-icore) and further scanned by using the 3D laboratory scanner to generate a third virtual 3D model to represent a clinical scenario where a patient's cast is needed (PU3DLab group). A monolithic zirconia crown design (cement space: margin 40 μm, 1 mm above 70 μm) was used on the virtual models, and crowns were fabricated out of presintered zirconia blocks (ZenostarT4; Wieland) by using a 5-axis milling machine (CORiTEC 550i; imes-icore). The crowns were sintered (Sinterofen HT-S Speed; Mihm-Vogt), and the vertical marginal discrepancy (VMD) was measured by ×100-magnification microscopy. Measurements were made at 384 points in 3 groups of 16 specimens. The measurements for each specimen were averaged, and VMD mean values were calculated. The Kruskal-Wallis test was used for the statistical analysis (α=.05). The Mann-Whitney U test and Bonferroni adjustment were further used to compare the pairs (α=.017).

RESULTS

The mean VMD value was 41 μm (median: 38 μm) for the control group, 44 μm (median: 42 μm) for the CBCTscan, and 60 μm (median: 58 μm) for the PU3DLab. No significant difference was found between control and CBCTscan groups (P=.274). However, there was a significant difference between control and PU3DLab and CBCTscan and PU3DLab groups (P<.001).

CONCLUSIONS

Marginal fit of the crowns fabricated by using the 3D laboratory scanner and through the direct use of CBCT was better than that of the crowns fabricated by using the workflow that combined the use of CBCT, PU cast, and 3D laboratory scanner. All tested protocols enabled the fabrication of monolithic zirconia crowns with a marginal discrepancy smaller than 120 μm.

Failure analysis of high performance polymers and new generation cubic zirconia used for implant-supported fixed, cantilevered prostheses

BACKGROUND

The load-to-failure performance of computer-assisted design and computer-assisted manufacturing (CAD-CAM) high performance polymers (HPP) and new generation cubic zirconia (Zir) material when used with titanium (Ti) bases for implant-supported fixed prostheses with cantilevers is unknown.

PURPOSE

To evaluate the load-to-failure performance of different CAD-CAM fabricated HPP and a new generation cubic Zir in a cantilevered situation when used with Ti bases.

MATERIALS AND METHODS

Five specimens with a Ti base and five specimens without Ti bases were fabricated from seven different CAD-CAM HPPs (100% PEEK [J and CP], 80% PEEK with 20% filler [BRE], 80% PEKK with 20% filler [PK], ceramic reinforced PEEK [ZZ], interlaced fiberglass and resin [TR], fiber-composite material [T]). Five specimens with Ti base and two specimens without Ti base were prepared from a new generation cubic Zir (DD) and a 3Y-TZP Zir (FZR) as the control group (N = 84). All specimens (8 × 7 × 30 mm) were stabilized using a clamp attached to the first 20 mm of each specimen for a 10 mm cantilever. Static loading was applied vertically on the cantilever and the maximum load-to-failure values (N) were analyzed using a two-way ANOVA and t-test (alpha = .05).

RESULTS

HPP and Zir specimens without Ti bases had significantly higher load-to-failure values than Ti based ones in all groups (P < .05). PK with Ti base had significantly lower load-to-failure values than other materials (P < .001). FZR showed significantly higher load-to-failure values than all HPPs and DD (P < .001).

CONCLUSIONS

Load-to-failure values of HPPs and Zir were lower when Ti bases were used. New generation cubic Zir and all HPPs had lower load-to-failure values than FZR. HPPs performance varied among tested materials. PEKK with Ti base had the lowest load-to-failure value.

Rescue of an implant-supported fixed complete prosthesis after the failure of an implant: A dental technique

This technique article describes the rescue of an existing implant-supported fixed complete prosthesis after the failure of a supporting implant. To achieve this, a system able to rescue the fixed prosthesis after placement of a new implant was used, and the protocol for performing this procedure is described.

Discoloration and translucency changes of CAD-CAM materials after exposure to beverages

STATEMENT OF PROBLEM

Color and translucency changes of recently introduced composite resin blocks after long-term exposure to various staining agents have not been fully investigated.

PURPOSE

The purpose of this in vitro study was to evaluate the color stainability and translucency changes of computer-aided design and computer-aided manufacturing (CAD-CAM) materials immersed in beverages with staining potential.

MATERIAL AND METHODS

Three types of CAD-CAM blocks were used: 3M Lava Ultimate (LU), GC Cerasmart (CS), and VITA Enamic (VE). Forty-five rectangular specimens (1.5-mm thickness) of each product were prepared. The specimens were divided into 3 subgroups (n=15 in each) according to the immersion beverage. The specimens were then immersed in distilled water, red wine, and coffee for 30 days. Color parameters (ΔE₀₀), the translucency parameter, and the contrast ratio were determined after 24 hours and 1 month. The Kruskal-Wallis and Mann-Whitney U tests and the Wilcoxon, Freidman, and repeated measurement ANOVA tests were used for statistical analysis (α=.05).

RESULTS

None of the materials showed clinically perceptible color changes except CS specimens immersed in coffee for 24 hours. The materials immersed in red wine and coffee for 1 month showed greater discoloration than those immersed in water (P<.05). The LU immersed in red wine showed the highest translucency changes, and VE was more resistant to translucency changes, as compared with the other materials tested. The contrast ratio values of the LU material were higher than those of the CS and VE materials in all the beverages.

CONCLUSIONS

The red wine and coffee caused significant changes in the color and translucency of these novel CAD-CAM materials after a long immersion period.

Are Stone Density and Location Useful Parameters That Can Determine the Endourological Surgical Technique for Kidney Stones That are Smaller than 2 cm? A Prospective Randomized Controlled Trial

Purpose: We aimed to evaluate whether these parameters could be guiding for us in selection between retrograde intrarenal surgery (RIRS) and mini-percutaneous nephrolithotomy (PNL) procedures in kidney stones that are smaller than 2 cm.

MATERIALS AND METHODS

The patients who had kidney stones smaller than two cm and were planned to undergo surgery were randomly distributed into 2 groups prospectively. RIRS was performed in the RIRS group using a 7.5-F fiberoptic flexible ureterorenoscope while mini-PNL group was dilated up to 16.5F and mini-PNL was per-formed with 12F nephroscopy. Preoperative characteristics, operative and postoperative results were compared in two groups. Thereafter, intra and intergroup comparisons were made to determine the effects of Hounsfield unit (HU) value indicating the stone density being higher or lower than 677 and stone location on stone-free rates.

RESULTS

The study involved 60 patients including 30 in each group. The groups' preoperative values were similar. The hospitalization time and the total duration of scopy were longer in mini-PNL when the postoperative values were compared (P < .0001). In terms of stone densities, HU values that were lower than 677 in the mini-PNL group affected the stone-free rate and reduced it from 100% (> 677HU) to 55.6% (< 677HU), whereas the change was significant (P = .005). Lower calyx stones affected the RIRS results negatively, whereas multiple calyceal stones affected the mini-PNL group negatively.

CONCLUSION

Both methods had a similar success rate, but lower pole stones, multiple calyceal stones and stone density parameters affected the stone-free rates significantly, and these may be effective in treatment selection.

The traditional practices used by couples with fertility problems, affecting factors, expected benefits, and learning paths: The Turkey Sample

Objective

Studies related to traditional practices and benefits have been usually performed among women. The literature regarding the traditional practices used by men in Turkey and around the world and their expected benefits is more limited. The aim of this study was to examine the traditional practices used by couples with fertility problems, affecting factors, expected benefits, and learning paths.

Materials and Methods

The descriptive study was performed between May and July 2017 in Izmir, Turkey. In total, 151 women with infertility were included. The data related to the use of this practice by men were obtained from women partners. "Personal information form" and "traditional practices evaluation form" were used to obtain the data.

Results

In total, 35.8% of the women and 25.8% of the men used traditional practices. The 24.4% of women and 52.1% of men used other practices such as figs, onion cures, and hacamat, whereas 18.2% of women and 14.9% of men used various herbs. The benefits they expected from traditional practices were facilitating conception, ensuring follicle development in women, increasing sperm count, and quality and facilitating conception in men. Overall, 37.0% of women learned of these practices from their friends, 30.7% of men learned from their partners, 20.4% of women and 20.6% of men learned from the internet.

Conclusion

The couples in this study widely used traditional practices to solve fertility problems and learned from their friends and partners.

Impact of number of registration points on the positional accuracy of a prosthetic treatment plan incorporated into a cone beam computed tomography scan by surface scan registration: An in vitro study

OBJECTIVES

To evaluate the accuracy of a prosthetic treatment plan incorporation into a cone beam computed tomography (CBCT) scan using point-based registration with three registration points selected and to evaluate the impact of number of registration points on prosthetic plan accuracy.

MATERIAL AND METHODS

A CBCT scan of a completely dentate master model with removable teeth was exposed after removing the mandibular left first premolar, second premolar, and first molar. A digital scan of the master model with all teeth present was made by scanning a stone replica using a laboratory scanner. The digital model was registered onto the three-dimensional (3D) volume rendering of the CBCT scan using implant planning software. The point-based registration was repeated using three, four, five, six, seven, eight, nine, and 10 reference points. Metrology software was used to measure the 3D deviation of the registered models for each reference point group on standard tessellation language (STL) files obtained from the CBCT scans. An STL file of the master model with all teeth present obtained from another CBCT scan was used as reference.

RESULTS

Using three registration points, the registered prosthetic plan had a mean absolute deviation of 17.63 µm from the reference. Increasing the number of registration points failed to demonstrate statistically significant effects on the deviation (p > 0.05).

CONCLUSIONS

For this clinical scenario, three registration points provided adequate accuracy for prosthetic plan incorporation into CBCT scans. Increasing the number of registration points had no significant impact on the prosthetic plan accuracy in this study.

Accuracy of different digital scanning techniques and scan bodies for complete-arch implant-supported prostheses

STATEMENT OF PROBLEM

The effect of various scan bodies and scanning techniques on the accuracy and scan time for completely edentulous patients is not well understood.

PURPOSE

The purpose of this in vitro study was to evaluate the effects of 4 scanning techniques and 5 intraoral scan bodies (ISBs) on the trueness, precision, and scan time in a completely edentulous arch with 4 implants.

MATERIAL AND METHODS

Five different ISB systems: AF, NT, DE, C3D, and ZI, and 4 different scanning techniques: unmodified master model (NO), glass fiduciary markers placed on the edentulous ridge (GB), pressure-indicating paste brushed over the ridge and palate (PP), and floss tied between the scan bodies (FL), were evaluated. Scan bodies were attached to an edentulous maxillary model with 4 dental implant analogs and scanned by using a structured blue light industrial scanner, and 5 consecutive digital scans of the model were made by using an intraoral scanner and 1 of the 4 techniques (n=5). The scans were superimposed on the master reference model, and the distance deviation and angular deviation of the scan bodies was calculated. The scan time was also recorded. A 2-factor ANOVA was used to examine the effect of scan body and technique on the trueness and scan time, with subsequent Tukey honestly significant difference or Bonferroni-corrected Student t tests. Precision was evaluated by tests for homogeneity of the variances between groups. Reliability for the entire study was evaluated using the intraclass correlation coefficient (α=.05 for all tests).

RESULTS

The overall reliability of the study according to intraclass correlations was 0.999. In terms of trueness, no statistically significant interaction was found between the effects of scan body and technique on the distance deviation (P=.246); however, the scan body (P=.031) and technique (P<.001) each had a significant effect independently. A statistically significant interaction was found between the effects of the scan body and technique on angular deviation (P<.001). Testing for the homogeneity of variances demonstrated significant differences in the precision among the groups in terms of distance deviation (P≤.013) and angular deviation (P≤.003). No statistically significant interaction was found between the effects of the scan body and technique (P=.076) on the scan time; however, the scan body alone was found to have a significant effect (P<.001).

CONCLUSIONS

The accuracy (trueness and precision) of complete-arch digital implant scans using ISBs was affected by both the scan body and scan technique when using an intraoral scanning system. The ZI scan body had significantly less distance deviation, whereas splinting scan bodies with floss led to significantly more distance deviation. The scan techniques with different surface modifications were not found to improve the scan accuracy. The use of different ISBs led to significant differences in the scan time.