A difference in application time between two direct orthodontic bonding methods: A prospective randomized clinical trial.

OBJECTIVE: This clinical study aimed to evaluate the difference in the time of application phase, employing the conventional and modified direct orthodontic bonding method. MATERIALS AND METHODS: Thirty patients who needed orthodontic therapy with fixed appliances were randomly divided into two equal groups (n = 15): the control and experimental group, according to the bonding method applied. A total of 600 metal brackets inch slot 0.022 (Mini Sprint®, Forestadent, Germany) were bonded to incisors, canines, and premolars using the light-cured adhesive Transbond XT (3M Unitek, Monrovia, CA, USA). The failure rates of the brackets were evaluated within 12 months. The independent samples t-test was applied. The Chi-square test and Fisher exact test were used for statistical analysis. RESULTS: The initial bonding time using the modified method was significantly shorter (3.27 min or 17.1% per patient) compared with the conventional bonding method (p < 0.001). Number of failed brackets between the two methods did not differ significantly (p = 0.226). CONCLUSION: The time of the application phase in initial bonding using the modified method (experimental group) was shorter than in control group. There was no statistically significant difference in the number of bond failures between the two methods. CLINICAL SIGNIFICANCE: The modified application phase of direct orthodontic bracket placement shortens the total bonding time and facilitates the manual work of orthodontists.

Immediately versus early placed bone-level-tapered implants supporting all-ceramic crowns on titanium base abutments: 1-year radiographic and pink esthetic outcomes of a multicenter pilot RCT.

OBJECTIVES: Aim of this study was to assess survival rates, radiographic, and pink esthetic outcomes of a bone-level-tapered (BLT) implant following immediate or early implant placement. MATERIALS AND METHODS: Patients in need of tooth extraction and one implant in the anterior or premolar area were recruited in five centers. Patients were randomly assigned to the immediate or early placement protocol. Implants were restored with all-ceramic crowns cemented to titanium-base-abutments. Radiographic bone levels, implant stability quotient (ISQ), and pink esthetic outcomes were assessed. Data were analyzed descriptively. Level of significance was set at 0.05. Differences between groups were tested using Wilcoxon-signed-rank and Mann-Whitney-U test as nonparametric tests. RESULTS: A total of 60 patients received 60 BLT implants (Institut Straumann). At 12-months, 59 implants (98.3%) were osseointegrated. The mean distance from implant shoulder to first bone-to-implant contact was 0.15 ± 0.59 mm without significant differences between the groups. Median ISQ values increased from 75.5 to 78.5. A mean buccal recession of 0.1 ± 0.70 mm occurred with no difference between groups. The mean papilla height gain in both groups was 0.5 ± 1.47 mm mesially and 0.4 ± 1.36 mm distally. CONCLUSIONS: After 1 year, immediately and early placed BLT implants exhibit similar bone level changes, ISQ values, and pink esthetic outcomes. CLINICAL SIGNIFICANCE: The present research contributes to the knowledge on clinical outcomes of immediately and early placed BLT implants restored with buccally microveneered ceramic single crowns out of two different ceramic materials. The research shows that similar esthetic and radiographic outcomes can be reached by means of immediate implant placement compared to the conventional early placement protocol. The improvement of esthetic soft-tissue parameters over time was shown for both implant placement protocols.

A multicenter randomized controlled clinical pilot study of buccally micro-veneered lithium-disilicate and zirconia crowns supported by titanium base abutments: 1-year outcomes.

OBJECTIVES: To investigate survival rates, technical and biologic outcomes of buccally micro-veneered all-ceramic single implant crowns. MATERIAL AND METHODS: Sixty subjects randomly received immediately or early placed implants. Crowns out of lithium-disilicate (n = 30) and zirconia-ceramic (n = 30) were bonded to titanium-base-abutments. Restorations were inspected at baseline (BL) and during follow-up visits (6, 12 months). Technical and biologic parameters were recorded. Data were analysed descriptively. Differences between groups were tested with Student's t-test. Paired T-test was used when comparing data from the same implant or tooth over time. Linear model repeated measures were used to test differences between materials over time. Differences in counts were evaluated using Pearson Chi-square test. The level of significance was at p < .05. RESULTS: After a mean observation time of 13.2 ± 2.4 months, 54 restorations were re-examined. The implant survival rate was 98.3%, and the restoration survival rate was 100%. One early implant failure occurred. Two minor chippings occurred in lithium-disilicate restorations. No chippings or fractures occurred in any zirconia restorations at 1 year (0%). The technical complication rate was 3.7%, with 7.7% complications among the lithium-disilicate restorations and no differences between the two materials (p = .558). At 1-year follow-up, mean Bleeding on Probing (BOP) was higher at implants (0.27 ± 0.3) than adjacent teeth (0.17 ± 0.18) (p = .046) with no differences between materials (p = .36). Differences in pocket probing depth (PPD) between implants and adjacent teeth were significant (p < .01). Jemt Index improved significantly from BL to 1-y-follow-up (p < .001). CONCLUSIONS: Preliminary results were good, suggesting that the ceramic type does not impact technical and biologic parameters.

Comparison of preemptive etoricoxib and dexamethasone in third molar surgery - a randomized controlled clinical trial of patient-reported and clinical outcomes.

OBJECTIVES: To compare preemptive single-dose etoricoxib and dexamethasone on postoperative patient satisfaction (pPS) and clinical parameters following the impacted mandibular third molar (IMTM) extraction. MATERIALS AND METHODS: A parallel-group, triple-blinded, controlled clinical study included a total of 90 patients (n = 30), randomized to receive: etoricoxib 90 mg, dexamethasone 4 mg, or no premedication (control group) 1 h before surgery. Paracetamol 500 mg was prescribed as rescue medication (RM). Check-ups were scheduled at 24 h, 48 h, and day 7 post-surgery. At each time point, pPS was assessed using the 5-point Likert scale. RM parameters, swelling, trismus, and the occurrence of adverse events were also recorded, and patients were instructed to rate the perceived pain on Visual Analogue Scale. RESULTS: In all the follow-up periods, data indicated significantly higher pPS scores in the preemptive medication groups when compared to the control group (p < 0.05). Both regimens delayed the first RM intake when compared to controls. In the etoricoxib group, a significantly lower total RM consumption was observed (p < 0.05). Dexamethasone significantly decreased swelling at each check-up and increased mouth opening at day 7 after the surgery (p < 0.05). CONCLUSIONS: Preemptive etoricoxib and dexamethasone elevate pPS after IMTM surgery. Etoricoxib improves RM parameters, while dexamethasone ameliorates the patient's postoperative functional ability. CLINICAL RELEVANCE: Preemptive etoricoxib and dexamethasone use may decrease patients' discomfort following the impacted mandibular third molar extraction. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT05791721. Date of Registration: 28/03/2023 (retrospectively registered).

Prosthetic failures in dental implant therapy.

Both fixed and removable implant-supported prostheses are well-established methods for replacing missing teeth in partially or fully edentulous patients. Numerous systematic reviews have been performed in recent years to evaluate the survival and complication rates of implant-retained fixed dental prostheses and implant-retained overdentures, displaying high 5-year survival rates ranging from 97.1% for fixed dental prostheses to 95%-100% for implant-retained overdentures. However, the survival rates only represent the prostheses remaining in use for a defined follow-up time, and do not account for the potential prosthetic complications that may have arisen and influence the general success of the implant treatment. The most common technical complications of fixed implant-retained single crowns are crown fracture, fractures of ceramic implant abutments, and esthetic problems. The predominant technical complication at multiple-unit, implant-retained fixed dental prostheses is fracture/chipping of the veneering ceramic. Reported technical complications for implant-retained overdentures are overdenture fracture or chipping of the veneer materials, whereas mechanical complications include implant fracture, attachment failure, and attachment housing or insert complications. To reduce the risk of such failures, a comprehensive pretreatment diagnostic work-up is essential, including defining the prosthetic goal with the aid of a wax-up or set-up and the associated ideal, prosthetically oriented three-dimensional implant position. Furthermore, selection of the ideal type of prosthesis, including the respective implant components and materials, is important for clinical long-term treatment success.

COVID-19: Another Cause of Dental Anxiety?

BACKGROUND Fear has always been closely linked to dentistry but it could be intensified by the objective risks imposed by the pandemic. The objective of this study was to determine the profile of the frightened dental patient during the COVID-19 pandemic and determine measures taken by dentists to reduce fear and increase security among their patients. MATERIAL AND METHODS An anonymous online survey was conducted between March 15 and April 15, 2021. The respondents were 2060 adult citizens of the Republic of Serbia. In addition to demographic data, data related to the COVID-19 pandemic, dental fear, and attitudes and fear of dental interventions during the ongoing pandemic were compiled. The data were analyzed using descriptive statistics: the chi-square test and Pearson's coefficient. RESULTS Seventy percent of the respondents felt some level of fear of the ongoing pandemic, 50% felt fear of going to a dentist during the pandemic, 20% considered a dental office a hotspot for the transmission of SARS-CoV-2, and 43% would visit their dentist only in the case of emergency. CONCLUSIONS The COVID-19 pandemic has affected the attitudes and behavior of people pertaining to visits to dental offices. Identifying frightened patients and their opinions and fears at this challenging time would make it easier for dentists to include protocols in their everyday practice to increase a sense of security among their patients, such as implementing preventive measures in front of the patients, ensuring an empty waiting room, and providing telephone consultations.

Immediate Vs Early Loading of Bone Level Tapered Dental Implants With Hydrophilic Surface in Rehabilitation of Fully Edentulous Maxilla: Clinical and Patient Centered Outcomes.

The aim was to: (1) compare changes among primary and secondary implant stability between immediate and early loaded implants in edentulous maxilla, (2) evaluate oral health-related quality of life (OHRQoL), and (3) determine patient satisfaction with 6 implant supported fixed full-arch dentures. A prospective, randomized controlled clinical trial was conducted on 24 edentulous maxilla patients. The BLT SLActive implants in 12 patients were immediately loaded with temporary restorations while 12 patients did not receive temporary restorations. Definitive (final) dentures were delivered to all patients after 6 weeks. Stability of the implants were assessed by insertion torque (IT) and resonance frequency analysis (RFA). Oral Health Impact Profile-19 (OHIP-19) questionnaire was used to evaluate OHRQoL and a visual analogue scale (VAS) was used for patient satisfaction. The IT value of implants assigned for immediate and early loading group was 27.17 ± 9.55 Ncm and 25.01 ± 11.06 Ncm, respectively. Changes in implant stability from baseline to week 6 were similar in both groups when measured by Penguin (P = .881) and Ostell (P = .828). Patients in the immediate loading group reported significantly lower OHIP physical pain scores (P = .016) and OHIP psychological disability score (P = .046), and the patients reported significantly higher VAS function score (P = .009) and VAS esthetics score (P = .009). Implant loading protocols do not have a significant effect on the change in implant stability 6 weeks after implantation; however, immediate loading significantly improves OHRQoL as well as satisfaction of patients with maxillary edentulism treated by fixed full-arch dentures. Future trials will determine the role of immediate loading protocol in clinical scenarios with various amounts of available jaw bone using different numbers of implants to retain a fixed prosthetic restoration in the edentulous maxilla.

Staining and aging-dependent changes in color of CAD-CAM materials.

STATEMENT OF PROBLEM: Consumption of some beverages and aging may affect the color of dental materials used in fixed prosthodontics, but their effect on recently introduced materials is not well known. PURPOSE: The purpose of this in vitro study was to evaluate staining, aging, and the exposure interval on color changes of computer-aided design and computer-aided manufacturing (CAD-CAM) resin nanoceramics (RNC), polymer-infiltrated ceramic-network (PICN) materials, and lithium silicate and lithium disilicate ceramics. MATERIAL AND METHODS: A total of 288 square-shaped, 1-mm-thick specimens prepared from Cerasmart, IPS e.max, Lava Ultimate, Shofu HC, Vita Enamic, and Vita Suprinity were polished by using laboratory and chairside methods in accordance with the manufacturers' instructions. Color data were recorded with a benchtop spectrophotometer, and CIEDE2000 color differences (ΔE00) were calculated. After the baseline measurements (T0), the specimens were divided into 3 groups (n=8) and exposed to staining in coffee and wine and to accelerated artificial aging. The specimens were stored in staining solutions at 37 °C for 60 (T1) and 120 hours (T2). Accelerated aging was performed by using a xenon lamp weathering test chamber for a total exposure of 150 (T1) and 300 kJ/m2 (T2). The results were analyzed by using the t test, ANOVA, and the Tukey honestly significant difference test (α=.05). Color differences of ΔE00 ≤0.8 and ≤1.8 corresponding to the 50:50% perceptibility threshold and 50:50% acceptability threshold were used to interpret the results. RESULTS: As color differences (ΔE00) between laboratory and chairside polishing were not statistically significant (T=-0.81, P=.418), only the results for chairside polished specimens were presented. Color differences for the T0-T1 comparisons ranged from 0.2 to 4.2, T0-T2 from 0.3 to 6.5, and T1-T2 from 0.1 to 2.3. ANOVA showed significance of factors and for interactions (P<.05). Lithium silicate-based and lithium disilicate-based ceramic materials were more color stable than RCN and PICN materials on exposure to coffee and red wine. Color changes greater than acceptability threshold after immersion in coffee were recorded for 3 (T0-T1), 4 (T0-T2), and 2 (T1-T2) materials. Corresponding findings after immersion in wine were 1, 3, and 0 and after artificial aging 0, 2, and 0. ΔE00 and ΔEab values were highly correlated (R2=0.97). CONCLUSIONS: No difference was found in color stability among laboratory and chairside polished specimens. Coffee caused the greatest color changes for T0-T2 interval. Staining-dependent color differences increased with increased exposure, except for IPS e.max and Vita Suprinity. For artificial aging, color change appeared to be material dependent.

Immediate versus early loading of immediately placed bone-level tapered dental implants with hydrophilic surface in full arch maxillary rehabilitation: A pilot randomized clinical trial with 2-year follow-up.

This study aimed to compare implant stabilities between the immediate and early loaded, immediately placed bone-level tapered dental implants in the maxilla and to evaluate marginal bone loss (MBL), oral health-related quality of life (OHRQoL), and patient satisfaction at a 2-year follow-up. A pilot, prospective, randomized, controlled clinical trial was conducted on 24 maxillary failing dentition patients. The bone-level tapered implants of 12 patients were immediately loaded with temporary restorations, while the other 12 patients did not receive any kind of temporization. Implant-supported screw-retained complete porcelain-fused-to-metal prostheses were delivered to all patients in the seventh postoperative week. The insertion torque values of implants assigned to the immediate and early loading groups were 33.0 ± 4.87 and 29.26 ± 8.31 Ncm, respectively. The dynamics of implant stability changes from implant placement up to a 2-year follow-up were similar for both groups (Penguin®, p = 0.268; Ostell®, p = 0.552), while the MBL was at submillimeter level. The cumulative implant survival rate was 91.80% for immediately loaded implants and 97.22% for early loaded implants, without significant difference (p = 0.162). The total score on the Oral Health Impact Profile questionnaire significantly decreased over time in both groups, indicating improvement in OHRQoL (p < 0.001), and the high level of patient satisfaction remained after 2 years of function regardless of a loading protocol. Both loading protocols, immediate and early, of six immediately placed bone-level tapered dental implants are an adequate treatment choice for fixed rehabilitation of the maxillary failing dentition.

Technical complication of a zirconia multiple-unit FDP supported by titanium base abutments - case report on a bonding failure and treatment alternative.

Monolithic zirconia implant-supported restorations connected to titanium bases or titanium inserts are increasing in popularity due to their application in a full digital workflow. These prefabricated abutments are connected to the all-ceramic superstructure by adhesive cementation. Although limited clinical data on the outcomes of this type of restoration are available, a few laboratory studies have shown possible debonding issues. This case report presents a bonding failure of a fixed dental prosthesis supported by titanium bases after short clinical use. A treatment alternative is also proposed using the available digital dental technology.

Comparison of the accuracy of optical impression systems in three different clinical situations.

PURPOSE: To investigate the differences in accuracy (trueness and precision) of five different optical impression systems. MATERIALS AND METHODS: The accuracy of the following optical impression systems was tested: (1) CEREC Bluecam (BL; Dentsply Sirona), (2) CEREC Omnicam (OM, Dentsply Sirona); (3) PlanScan (PL; Planmeca); (4) True Definition Scanner (TD; 3M ESPE); and (5) Trios 3 (TR; 3Shape). A standard plastic study model represented a patient with a fully dentate maxilla (ANA-4 V CER, frasaco). Three clinical situations were simulated: Patient 1 (P1): fully dentate; Patient 2 (P2): anterior partial edentulism (two missing incisors); and Patient 3 (P3): posterior partial edentulism (P3) (missing premolar and molar). The models were scanned with a reference scanner (IScan D104i, Imetric), and the digitalized models were used as reference for all comparisons. Then, optical impressions were made for the three clinical scenarios (n = 10 per group). RESULTS: In situation P1, the TD group provided the highest trueness (180.2 ± 46.3µm). In situation P2, the highest trueness was found in the TD (97.9 ± 27.6 µm) and TR (105 ± 9.5µm) groups, and in situation P3, TR had the highest trueness (P < .05) with a median RMS value of 76.2 ± 5.6 µm. In terms of precision, TR provided the highest precision (P < .05) in all three clinical situations, with RMS values 76.7 ± 26 µm for P1, 46.8 ± 14.1 µm for P2, and 39.7 ± 9.1 µm for P3. CONCLUSION: Two optical impression systems (TR and TD) were superior to the other tested systems in most of the measurements. However, none of the tested systems was clearly superior with respect to both trueness and precision.

Apolipoprotein ɛ4 Allele and Dental Occlusion Deficiency as Risk Factors for Alzheimer's Disease.

Compromised dentition has been suggested to pose a significant risk factor for dementia. It was mainly investigated through insufficient tooth number, disregarding contact between opposing teeth (dental occlusion). The ɛ4 allele of apolipoprotein (APOE4) is the primary genetic marker for the late onset of Alzheimer's disease (AD). However, APOE4 and dental occlusion have not yet been investigated as possible associated risk factors for AD. The study was aimed to examine the impact of dental status and different APOE gene variants on AD occurrence. Secondly, sociodemographic variables were investigated as factors potentially associated with AD. The case-control study included two groups: 116 patients with AD (according to the NINDS-ADRDA criteria) and 63 controls (Mini-Mental State Examination scores ≥24). The analysis of APOE gene polymorphism was conducted through PCR reaction. Dental examination included recording of number of teeth, presence of fixed or removable dentures, and number of functional tooth units (FTU). Regression analysis was used to investigate the joint effect of the clinical and genetic variables on AD. Results showed that patients with AD were more often carriers of ɛ3/ɛ4 genotype and ɛ4 allele, had lower number of teeth and FTU, and were less likely to be married, live in home, and had less chronic diseases, compared to the controls. Regression analysis showed that presence of APOE4 allele and the number of total FTU remained associated with AD, even when adjusted for age, sex, and level of education. In conclusion, deficient dental occlusion and presence of APOE4 may independently increase risk for AD.

Combined predictive effects of sentential and visual constraints in early audiovisual speech processing.

In language comprehension, a variety of contextual cues act in unison to render upcoming words more or less predictable. As a sentence unfolds, we use prior context (sentential constraints) to predict what the next words might be. Additionally, in a conversation, we can predict upcoming sounds through observing the mouth movements of a speaker (visual constraints). In electrophysiological studies, effects of visual constraints have typically been observed early in language processing, while effects of sentential constraints have typically been observed later. We hypothesized that the visual and the sentential constraints might feed into the same predictive process such that effects of sentential constraints might also be detectable early in language processing through modulations of the early effects of visual salience. We presented participants with audiovisual speech while recording their brain activity with magnetoencephalography. Participants saw videos of a person saying sentences where the last word was either sententially constrained or not, and began with a salient or non-salient mouth movement. We found that sentential constraints indeed exerted an early (N1) influence on language processing. Sentential modulations of the N1 visual predictability effect were visible in brain areas associated with semantic processing, and were differently expressed in the two hemispheres. In the left hemisphere, visual and sentential constraints jointly suppressed the auditory evoked field, while the right hemisphere was sensitive to visual constraints only in the absence of strong sentential constraints. These results suggest that sentential and visual constraints can jointly influence even very early stages of audiovisual speech comprehension.

Effects of coenzyme Q10 encapsulated in nanoliposomes on wound healing processes after tooth extraction.

BACKGROUND/PURPOSE: Tooth extraction is often followed by a number of different complications that demand additional treatment. In order to accelerate healing processes and decrease the complication occurrence various agents, growth factors, natural and synthetic antioxidants (e.g coenzyme Q10-CoQ10), are applied. Due to the partially known health-promoting effects of CoQ10 we decided to assess potential of it's encapsulated in nanoliposomes form on wound healing process following tooth extraction. MATERIALS AND METHODS: Effects of free and encapsulated form of CoQ10 on wound healing processes after tooth extraction in rats, 3 and 7 days following surgical procedure, was studied by means of tissue biochemical (myeloperoxidase activity and nitric oxide (NO) concentrations) and pathohistological analysis. RESULTS: The obtained results indicate that the encapsulated form of CoQ10 compared to control and CoQ10 treated animals statistically significantly decreases inflammatory process estimated through myeloperoxidase activity and NO concentrations, as well as based on histopathological analysis 3 and 7 days following surgery. CONCLUSION: The results of this study unequivocally prove that the encapsulation of CoQ10 in nanoliposomes enhances CoQ10 activity by accelerating wound healing process after tooth extraction.

Curcumin nanoliposomes mitigate wound tissue inflammatory response caused by tooth extraction

Abstract Curcumin is a plant-derived compound with polypharmacological properties that are hampered by its poor solubility, fast degradation, etc. Wound closure complications that follow tooth extraction are numerous, and relatively frequently additional treatment is needed to prevent unwanted process chronification. The present study aims to compare the effects of free and the nanoliposome-encapsulated curcumin on tooth extraction wound closure. The experiments were performed on Wistar rats where both forms of curcumin were applied topically on a tooth extraction wound for seven days. Changes in tissue oxidative stress (malondialdehyde and oxidized proteins concentrations, and catalase activity) and inflammation (nitric oxide levels and myeloperoxidase activity) related parameters were studied three and seven days following the tooth extraction. Also, the extent of pathohistological changes and osteopontin immunohistochemical expression were studied. The obtained results indicate that both forms of curcumin prevent an increase in oxidative stress and inflammation-related parameters in the studied samples at 3-and 7-day time points. Additionally, we found that curcumin diminished tissue inflammatory response and osteopontin expression, while at the same time it caused faster granulation tissue maturation. The encapsulation of curcumin in nanoliposomes proved to be better in improving the extraction wound healing process than the free curcumin, giving this formulation a potential in the pharmaceutical industry.

[Transcutaneous electrical nerve stimulation therapy in reduction of orofacial pain].

INTRODUCTION: Patients with craniomandibular disorders suffer from hypertonic, fatigued and painful masticatory muscles.This condition can lead to limitation of mandibular jaw movements. All of these symptoms and signs are included in myofascial pain dysfunction syndrome.Transcutaneous electrical nerve stimulation (TENS) has been used for treatment of these patients. OBJECTIVE: The aim of this study was to assess the effect ofTENS therapy on chronic pain reduction in patients with the muscular dysfunction symptom. METHODS: In order to evaluate the effect ofTENS therapy before and after the treatment, Craniomandibular Index (Helkimo) was used. Pain intensity was measured by VAS. Patients had TENS treatment over two-week period. BURST TENS modality was used. Current intensity was individually adjusted. RESULTS: Two patients did not respond to TENS therapy. Complete pain reduction was recorded in 8 patients, while pain reduction was not significantly different after TENS therapy in 10 patients. CONCLUSION: TENS therapy was confirmed as therapeutic procedure in orofacial muscle relaxation and pain reduction.

Reliability of conventional shade guides in teeth color determination.

BACKGROUND/AIM: Color matching in prosthodontic therapy is a very important task because it influences the esthetic value of dental restorations. Visual shade matching represents the most frequently applied method in clinical practice. Instrumental measurements provide objective and quantified data in color assessment of natural teeth and restorations. In instrumental shade analysis, the goal is to achieve the smallest deltaE value possible, indicating the most accurate shade match. The aim of this study was to evaluate the reliability of commercially available ceramic shade guides. METHODS: VITA Easyshade spectrophotometer (VITA, Germany) was used for instrumental color determination. Utilizing this device, color samples of ten VITA Classical and ten VITA 3D - Master shade guides were analyzed. Each color sample from all shade guides was measured three times and the basic parameters of color quality were examined: deltaL, deltaC, deltaH, deltaE, deltaElc. Based on these parameters spectrophotometer marks the shade matching as good, fair or adjust. RESULTS: After performing 1,248 measurements of ceramic color samples, frequency of evaluations adjust, fair and good were statistically significantly different between VITA Classical and VITA 3D Master shade guides (p = 0.002). There were 27.1% cases scored as adjust, 66.3% as fair and 6.7% as good. In VITA 3D - Master shade guides 30.9% cases were evaluated as adjust, 66.4% as fair and 2.7% cases as good. CONCLUSION: Color samples from different shade guides, produced by the same manufacturer, show variability in basic color parameters, which once again proves the lack of precision and nonuniformity of the conventional method.

[Immediate implant loading with fixed dental restorations--an animal model study].

BACKGROUND/AIM: Immediate loading is considered to be the most innovative technique in contemporary implant dentistry. Recent clinical and experimental findings have demonstrated that only implants with high primary stability can be subjected to immediate loading protocol with predictable results. It is generally accepted that the most important prerequsite for successful osseointegration is achievement and maintenance of implant stability. The aim of this in vivo study was to investigate the possibility for successful application of immediate loading protocol in implant systems with different surface properties. METHODS: In the experimental study 2 mongrel dogs were edentulated bilaterally in the mandibular and maxillary premolar areas. After 3 months implants were placed in a pattern 4 different commercially available implants per quadrant (n = 32): Mk III TiUnite (Nobel Biocare, Sweden), ITI TPS (Straumann, Switzerland), 31-Osseotite (Implant Innovation, USA) and XiVE Cell-Plus (Friadent, Germany). Implants were subjected to immediate loading with 4 unit gold cast bridges, 2 days post implantation. The assessment of implant stability and immediate loading possibilities were done by performing Resonance frequency analysis (RFA). RESULTS: After a 6-month loading period all bridges were in function and all implants occurred well osseointegrated. When summarizing the Implant Stability Quotient (ISQ) values, it was noted that resonance frequency was significantly higher for mandibular implants. The results of this experimental setting showed that all evaluated surfaces achieved good implant stability. Increase of ISQ values was found for all implants in the mandible and partially decrease of ISQ values for maxillary implants after 6 months of functional loading with 4 unit bridges. CONCLUSIONS: Investigated endooseal implants did not show different degree of osseointegration, because there was not statisticaly significant difference among observed parameters (ISQh i ISQp) between implant systems.