pH Value Of Saliva Research Articles

Effects of the fixed orthodontic therapy on biochemical and microbiological parameters of saliva

Introduction/Objective. Malocclusions are one of the most frequent disorders in dentistry, and pose a risk for the onset of caries and periodontal diseases. Fixed orthodontic treatment solves the problem of malocclusions; however, it requires simultaneous cooperation of the patients, parents, and dentists involved. The objective of this study is to examine the effects of fixed orthodontic therapy on the Streptococcus mutans and Lactobacillus spp. bacteria in saliva, the pH value, and buffering capacity of saliva. Methods. The research was carried out at the Faculty of Medicine in Foca, Department of Dentistry. The study included 100 respondents, aged 13 to 17 years. The respondents were divided into two groups: the study group (respondents wearing fixed braces) and the control group (respondents not subjected to fixed braces therapy). Saliva samples were taken from the respondents four, 12, and 18 weeks after the start of the orthodontic therapy. The study used the bacteria caries risk test (CRT) and CRT buffer (Ivoclar Vivadent). Results. The study showed an increased number of bacteria in saliva of the respondents during all three follow-up periods (?2 test, p = 0.001). The largest numbers of the Streptococcus mutans and Lactobacillus spp. bacteria were found in week 12 of the therapy. Saliva pH value and buffering capacity of saliva increased statistically significantly in week 12 of the therapy (?2 test, p = 0.001). Conclusion. Oral conditions in patients changed during the fixed orthodontic therapy: the number of bacteria increased, the pH value and buffering capacity of saliva changed. It was necessary to use preventive measures in order to avoid complications during the fixed orthodontic appliances therapy.

Chair-side saliva diagnostic tests: An evaluation tool for xerostomia and caries risk assessment in children with type 1 diabetes

ObjectivesThe aim of this cross-sectional study was to investigate how the level of metabolic control affects salivary function, xerostomia prevalence and incidence of caries, in children and adolescents with type 1 diabetes. MethodsFor the purpose of this study, a total of 150 children and adolescents (10–18 years old) were examined and allocated among 3 groups: 50 patients poorly-controlled (HbA1c≥7.5%), 50 well-controlled (HbA1c<7.5%) and 50 age- and sex-matched healthy controls. All subjects were examined for dental caries, oral hygiene and salivary factors. Assessments of salivary characteristics included self-reported xerostomia, quantification of resting and stimulated whole saliva flow rates, pH values, buffering capacity and saliva’s viscosity. A questionnaire and a chair-side saliva testing kit were used for the evaluation of salivary function. Caries incidence was recorded using DMFT index. Plaque index and gingival index were additionally evaluated. Data were analysed by Chi-square and Kruskal-Wallis tests. ResultsHigher caries levels, higher prevalence of xerostomia and a decreased unstimulated salivary flow rate were recorded in poorly-controlled diabetics. The average caries indexes were DMFT(poor c) 3.6, DMFT(well c)1.2, DMFT(healthy) 1.5, p < 0.05). Salivary status and caries index were not found to be significantly different between well-controlled patients and healthy controls. ConclusionsThe results of this study indicated that chair-side salivary tests provide the practitioners with an easy-to use and quick method for the evaluation of salivary function and caries risk assessment in young patients with diabetes. Clinical significanceThe use of chair-side salivary tests provide the practitioners with an easy-to use and quick method for caries risk assessment and confirmation of clinical symptoms and signs in young patients with diabetes. They could be easily incorporated into daily office routine and may provide a useful tool for screening at risk patients and a simple way to communicate with the patients the need for further interventions for prevention.

Oral mucosa and salivary findings in non-diabetic patients with chronic kidney disease

IntroductionChronic kidney disease (CKD) and dialysis treatment could affect oral mucosa and cause qualitative or quantitative changes of saliva. ObjectiveThe aim of the study was to investigate oral manifestations, unstimulated salivary flow rate (USFR), salivary pH value and biochemical composition of saliva in non-diabetic patients with CKD. DesignThe study group (PD) consisted of 50 pre-dialysis patients diagnosed with CKD, positive control group (HD) of 25 haemodialysis patients and negative control (H) of 25 age and gender-matched healthy persons. Creatinine clearance rate (CrCl) was calculated from the blood creatinine using the Cockcroft-Gault formula. After a detailed intraoral examination, whole unstimulated saliva samples were collected to determine salivary pH value, and biochemical composition using a spectrophotometric method. ResultsStatistical analysis revealed that PD subjects had more oral lesions (p < 0.05) and symptoms (p < 0.001) than controls. The mean CrCl was significantly lower (p < 0.05) in CKD subjects with pale mucosa, xerostomia, dysgeusia, and uremic odour, comparing to those without listed symptoms. PD subjects had significantly decreased USFR and increased pH, urea and creatinine than H controls (p < 0.05). A moderately strong positive correlation between serum and salivary creatinine in both PD (p < 0.05) and HD (p < 0.05) groups was found. ConclusionThis study confirmed that xerostomia and dysgeusia are major symptoms among pre-dialysis patients. Their presence along with uremic odour and pale mucosa is directly related to decreased kidney function. On the diagnostic point, decreased USFR, especially hyposalivation and increased salivary creatinine, should be considered a significant indicator of CKD in stages before dialysis therapy.

Study of electrochemical corrosion of biocompatible Co–Cr and Ni–Cr dental alloys in artificial saliva. Influence of pH of the solution

The pH of saliva is changeable and variable in the oral environment in function of the quality of foods and liquids ingested. Also, the biocompatibility of a material for dental applications is checked not only by clinical and epidemiological studies, but also by corrosion resistance studies. The aim of this study was to investigate the influence of the pH value of artificial saliva on the corrosion of the Co–Cr and Ni–Cr dental alloys, using different electrochemical techniques such as: cyclic voltammetry, open circuit potential (OCP) measurement, polarization curves and electrochemical impedance spectroscopy (EIS). The obtained results are complementary with scanning electron microscopy (SEM) coupled with energy-dispersive X-ray spectroscopy (EDXS) analysis, proving that Co–Cr alloy is more resistant in time, and recommending it for successful treatment of patients with dental prosthesis having metal frameworks.

The increased sensitivity of dentin: the mechanisms of remineralization using toothpaste with tin fluoride

The purpose of the study was clinical and laboratory analysis of the remineralizing properties and clinical efficacy of the course application of the Sensodyne Rapid Relief therapeutic and prophylactic toothpaste for sensitive teeth with tin fluoride. The study involved 50 overwise healthy patients aged from 18 to 25 years diagnosed with a localized form of hyperesthesia of hard dental tissues and no signs of acute inflammation of periodontal tissues. After 7 days of clinical observation and daily use of the toothpaste the hygienic condition of the oral cavity in all patients improved: oral hygiene index was 1.02±0.2 units; gum inflammation index (PMA) - 8.0±1.5%; the absence of hyperesthesia was diagnosed (1 point, p≤0.05). Examination of patients after 14 and 28 days confirmed the absence of pain in 100%, the organoleptic properties of the toothpaste under investigation were also highly appreciated by the participants. A laboratory study showed that patients have an increase in the pH value of mixed saliva and a decrease in its buffer capacity by 13.4±2.25%, which contributes to a more effective remineralizing effect of calcium ions by calcium-binding proteins of mixed saliva. The concentration of fluoride ions in the saliva of patients of both groups increased by average rate of 34±0.5% per week. The combination of tin and fluoride is more effective than fluoride alone. The presence of tin ions causes a higher ability of fluorides to bind with calcium ions on the surface of the dentin and dentinal tubules, inhibits the process of demineralization, enhances the additive interaction of the ions forming the acid-resistant layer on the surface of the dentin and dentinal tubules, leading to a decrease in hyperesthesia of the teeth.

Measurement of unstimulated salivary flow rate in healthy children aged 6 to 15 years

The aim of the present study was to measure unstimulated saliva flow rate (uSFR), pH value and buffer capacity in healthy children aged 6 to 15 years to serve as reference values for subsequent investigations, in particular to define threshold values for abnormality. Our basic data will power the limited amount of currently available data on salivary flow rate in healthy children. The uSFR was evaluated for correlations with pH value and buffer capacity. The unstimulated saliva of 274 children aged 6 to 15 years was collected (n: 154) by the spitting method within three minutes. The samples were examined immediately after saliva collection in terms of uSFR, pH value and buffer capacity. From the 274 participating children 18 were excluded due to the intake of medication. The medians (IQR) of uSFR of the tested children were 0.87 (0.54, 1.11) ml/min for boys, 0.65 (0.37, 0.98) ml/min for girls and 0.76 (0.49, 1.05) ml/min in total. The uSFR correlated with the pH value and the buffer capacity (p < 0.001). For different genders there was a statistically significant difference regarding uSFR (p = 0.008) and pH value (p = 0.016). Based on the available data, the pH value and the buffer capacity were closely related to the uSFR. Boys seemed to have a higher uSFR than girls.

Measurement of unstimulated salivary flow rate in healthy children aged 6 to 15 years

The aim of the present study was to measure unstimulated saliva flow rate (uSFR), pH value and buffer capacity in healthy children aged 6 to 15 years to serve as reference values for subsequent investigations, in particular to define threshold values for abnormality. Our basic data will power the limited amount of currently available data on salivary flow rate in healthy children. The uSFR was evaluated for correlations with pH value and buffer capacity. The unstimulated saliva of 274 children aged 6 to 15 years was collected (n: 154) by the spitting method within three minutes. The samples were examined immediately after saliva collection in terms of uSFR, pH value and buffer capacity. From the 274 participating children 18 were excluded due to the intake of medication. The medians (IQR) of uSFR of the tested children were 0.87 (0.54, 1.11) ml/min for boys, 0.65 (0.37, 0.98) ml/min for girls and 0.76 (0.49, 1.05) ml/min in total. The uSFR correlated with the pH value and the buffer capacity (p < 0.001). For different genders there was a statistically significant difference regarding uSFR (p = 0.008) and pH value (p = 0.016). Based on the available data, the pH value and the buffer capacity were closely related to the uSFR. Boys seemed to have a higher uSFR than girls.

Subjective, functional and microbiological parameters of the oral cavity in gastroesophageal reflux patients with acidic and subacidic refluctant

The aim of the study was to compare dental and periodontal status, oral hygiene, salivation rate, functional parameters of saliva and oral microbiota composition in patients with gastroesophageal reflux disease (GERD) with acidic and subacidic refluctant. The study comprised 69 participants divided in 3 groups: 22 healthy volunteers (controls) and 2 main groups: 25 GERD patients with acidic (group 2) and 22 patients with subacidic refluctant (group 3). Poor dental and periodontal condition was revealed in group 3 patients probably because of aggressive intestinal content reflux in the oral cavity resulting in higher PMA an saliva pH values, Escherichia coli species in oral microbiota and low buffer capacity of saliva. The results show that GERD may be suspected due to oral manifestations thus promoting it's prompt treatment.

Study of the influence of medicinal preparations on the indicators of mixed saliva in patients with essential hypertension

Aim. To identify the effect of drugs on the functional state of the salivary glands in patients with essential hypertension. Methods. A total of 38 hypertensive patients were examined. Depending on the prescribed drug therapy, all patients were divided into four groups: group 1 received an angiotensin-converting enzyme inhibitor; group 2 received a beta-blocker; group 3 received a slow calcium channel blocker, group 4 received a statin. For the analysis of salivary glands, the salivation rate was calculated, pH of the mixed saliva and activity of lactate dehydrogenase, alkaline phosphatase, aspartate aminotransferase, and alanine aminotransferase were measured. Results. In the mixed saliva of hypertensive patients, the salivation rate decreased in patients taking statins. The pH values of saliva in all groups were within neutral values, from 6.80 to 7.04. The amount of total protein was increased in patients taking angiotensin-converting enzyme inhibitors and statins, and was reduced in patients taking beta-adrenoblockers and slow calcium channel blockers. High activity of lactate dehydrogenase and aspartate aminotransferase was detected in patients taking statins, which indicates activation of anaerobic bacteria and inflammatory processes in the oral cavity. The increased activity of alkaline phosphatase, noted in patients taking beta-adrenoblockers, suggests possible violation of the processes of enamel mineralization. High activity of alkaline phosphatase and aspartate aminotransferase in the mixed saliva of observed patients coincides with the increase of papillary marginal alveolar index up to 27±4.6%, which indicates the development of pathology in the periodontal tissues. Conclusion. In patients receiving statins salivation function was suppressed; increased activity of lactate dehydrogenase and aspartate aminotransferase in the mixed saliva indicates activation of anaerobic microflora and tissue protein breakdown in the oral cavity.

Impact of inhalation therapy on the incidence of carious lesions in patients with asthma and COPD.

Objective:The aim of this study was to investigate the incidence of carious lesions, the amount of salivary flow rate and pH value in patients with asthma and chronic obstructive pulmonary diseases (COPD), using inhalation therapy. The obtained results were compared with the results of adult healthy subjects, forming a control group.Material and Methods:The study included 80 participants aging between 18 and 65 years. The experimental group (EG) was comprised of 40 participants, previously diagnosed with asthma or COPD undergoing inhalation therapy for more than five years. The control group (CG), comprised of 40 participants, mirrored the same age and gender status of the EG. Dental status was determined by decayed, missing, and filled teeth (DMFT index). Quantity and pH value of saliva were determined in the laboratory.Results:In the EG, the mean value of the salivary flow rate and pH value were statistically significantly lower than in the CG (p<0.001). Patients in the EG had a higher value of DMFT index when compared with the CG, although the difference was not statistically significant (p=0.199). Mean number of decayed teeth, as well as missing teeth, in the EG was statistically significantly higher than in the CG (p<0.001). Mean number of filled teeth in the EG was statistically significantly lower than in the CG (p<0.001).Conclusion:It was found that patients undergoing inhalation therapy face increasing risk of dental caries due to the lower salivary flow rate and pH value along with the inhalation therapy. They should receive intensive preventive care, including oral hygiene instruction and dietary advice.

The effect of prolonged immersion of giomer bulk-fill composite resin on the pH value of artificial saliva and resin surface roughness

This study aimed to determine the effect of immersion time on the surface roughness of Giomer Bulk-Fill composite resin and on the pH value of artificial saliva. Sixty-three specimens were divided into nine groups and immersed in artificial saliva with pH values of 7, 5.5, and 4.5 for 1 hour, 24 hours, and 72 hours at 37 °C. The changes in artificial saliva pH were measured using a pH meter and the surface roughness was measured using a surface roughness tester. Longer immersion time increases the pH of artificial saliva and the surface roughness of Giomer Bulk-Fill composite resin.

Erosive Drinks Impact on Fluoride Potential Change and Ph Value of Artificial Saliva In Vitro

Erosive Drinks Impact on Fluoride Potential Change and Ph Value of Artificial Saliva In Vitro

Prevalence and possible predictors of the occurence of denture stomatitis in patients older than 60 years

Background/Aim. Denture stomatitis (DS) is one of the most common oral health problems among elderly population with removable dentures. Despite the high prevalence, etiology of the disease is not completely understood. It appears to be multifactorial, with a predominance of local factors. The aim of the study was to determine the prevalence and risk factors that contribute to the development of DS in upper removable denture wearers. Methods. This clinical study comprised three groups of subjects with upper removable dentures: the DS group, and the positive and negative control groups. Swab samples were taken from the tongue and palatal mucosa for microbiological examination. Data of denture age, dentures night wearing, unstimulated salivary flow rate (USFR) and saliva pH values were evaluated for all the participants. Results. The prevalence of DS was found to be 26.5%. Significantly higher values of overnight wearing (p = 0.000) and the mean age of dentures (p = 0.022) were found in the DS group compared to the controls. In relation to the positive mycological finding, a borderline significance difference among the groups was confirmed (p = 0.053). No significant association was found between DS and gender, age, the type of dentures, USFR, pH of saliva and bacteria findings. The patients who wore dentures at night had 26 times more chances to get DS compared to the patients who did not wear them overnight. Conclusion. This study confirms similar characteristics of DS prevalence in elderly population of Vojvodina compared to European. Continuous (overnight) wearing of dentures is considered to be major direct risk factor for DS development, while secondary role is attributed to denture age and oral Candida infection.

The influence of sampling method on electrolyte concentrations, pH and buffer capacity of saliva in healthy individuals

Abstract Introduction Saliva is a complex secretion, which plays an important role in maintenance of oral health. Analysis of saliva is fast, simple and non-invasive, and it is increasingly used as a biological sample for determination of various biochemical markers. The aim was to determine the influence of unstimulated saliva collection methods for measuring electrolytes concentration (sodium, potassium, calcium), pH and buffer capacity of saliva in healthy subjects. Material and methods 30 healthy subjects, males and females, aged 18 to 20 years, without oral and systemic diseases were included in the study. Unstimulated saliva samples were taken using a special tube (Salivette) and via direct spitting into the test tube. The concentrations of sodium and potassium were determined by flame emission photometry while spectrophotometry was used for calcium concentration. For the analysis of pH value of saliva pH-meter was used, while saliva buffer capacity was determined by titration with HCl (0.005 mol/L). Results The level of sodium in unstimulated saliva collected in test tubes was 8.43 ± 3.92 mmol/L and in special tubes 7.90 ± 4.33 mmol/L. Potassium level in unstimulated saliva collected in test tubes was 13.62 ± 0.99 mmol/L while in special tubes it was 13.54 ± 0.94 mmol/L. Mean values of sodium and potassium in unstimulated saliva didn’t show statistically significant difference in their concentrations between the two methods of collecting saliva. In contrast to these electrolytes, calcium concentration was higher in the samples of saliva collected with special tubes (2.04 ± 1.05 mmol/L) compared to the samples taken by direct spitting into the test tube (1.38 ± 1.18 mmol/L) with statistically significant difference (p &lt; 0.05). By analyzing the pH of unstimulated saliva it was found that the average pH value of saliva collected with special tubes was 7.05 ± 0.32, and after direct spitting into test tubes it was 7.35 ± 0.41. Buffer capacity of saliva in healthy subjects was lower after taking with special tubes (5.18 ± 0.74) compared to test tubes (5.36 ± 0.85), but without statistical difference. Conclusion Unstimulated saliva collecting methods using cotton pads (salivette) and direct spitting in the test tube did not affect the value of pH, buffer capacity, the concentrations of sodium and potassium, but affected the concentration of calcium in saliva from healthy subjects.

In Vivo Release Kinetics and Antibacterial Activity of Novel Polyphenols-Enriched Chewing Gums.

Chewing gums may be particularly effective means for delivering and maintaining bioactive molecules, included in the gum formulation, able to have an anti-cariogenic effect. The purposes of this study were: to develop novel chewing gums containing quercetin (Qt); to evaluate their release using in vivo trial; finally, to test their in vivo antibacterial effect against oral Streptococcus mutans strains. A preliminary study was performed to produce new gums, enriched with the polyphenol quercetin. Then, a first in vivo experimental study was assessed to test the percentages of Qt released in the saliva of young volunteers. Moreover, a second clinical trial was performed to analyze the antibacterial capability of these enriched chewing gums against S. mutans strains after 14 days of daily consumption. The release analysis showed that a more effective release of Qt occurs in the first minutes of chewing, and it does not change saliva pH values. Moreover, Qt included in gums demonstrates an effective antibacterial activity, showing a reduction of the concentration of S. mutans strains in saliva samples, especially after 7 days. Qt included in experimental chewing gums could be efficiently released into the oral cavity and could promote an effective anti-caries concentration in volunteer’s saliva, without changing salivary pH values.

Synthesis and characterization of Ti–Co alloy foam for biomedical applications

Highly porous Ti–Co alloy specimens for biomedical applications were synthesized by powder metallurgy based space holder technique. Ti alloys have high melting temperature and affinity for oxygen, which makes Ti alloys difficult to be processed. The Co addition reduces the melting temperature and Ti–Co alloy was sintered at lower temperatures. The electrochemical corrosion behaviour of the specimens was examined in the artificial saliva solution. The effects of Co content of the alloy, the pH value and fluoride concentration of the artificial saliva solution on the electrochemical corrosion properties of the specimens were investigated. The microstructure and mechanical properties of the specimens were examined. The electrochemical impedance spectroscopy results indicate that the corrosion resistance of the specimens decreases at high fluoride concentrations and low pH value. The defect density increases with increasing the fluoride concentration and decreasing the pH value of artificial saliva according to Mott–Schottky analysis.

Microstructure and metallic ion release of pure titanium and Ti–13Nb–13Zr alloy processed by high pressure torsion

Significant enhancement of mechanical properties of metallic biomaterials can be achieved by grain refinement obtained by severe plastic deformation. The purpose of this study was to determine metallic ion release from commercially pure titanium (CPTi) and Ti–13Nb–13Zr alloy processed by high pressure torsion (HPT). The materials microstructures, in the initial state and after HPT deformation, were examined by scanning and transmission electron microscopy. The microhardness was determined along the radius of the disc-shaped samples of ultrafine-grained (UFG) CPTi and Ti–13Nb–13Zr alloy in order to evaluate homogeneity of HPT-processed materials. The quantities of released ions were determined using inductively coupled plasma-mass spectrophotometer for samples immersed in artificial saliva at 37°C for 7days. Also, the effect of artificial saliva pH value on metallic ion release was estimated. Obtained results revealed that the quantities of released ions from UFG CPTi and Ti–13Nb–13Zr alloy obtained by HPT process were higher than the quantities of released ions from CPTi and Ti–13Nb–13Zr alloy produced by traditional casting. This behavior can be explained by the fact that metallic ions are easily released from microstructure with smaller grains achieved by HPT process.

Impact Behavior of Three Notched All-Ceramic Restorations after Soaking in Artificial Saliva.

Biomechanics play a critical role in influencing the clinical applications of all-ceramic dental restorations. The restorative biomaterials have to demonstrate mechanical durability in the oral environment because they are always exposed to a variety of oral environments. This study was designed to evaluate the effect of soaking time, notch and saliva pH values on the impact energy of three commonly used all-ceramic materials for CAD/CAM. The leucite-reinforced glass ceramic (ProCAD), lithium disilicate glass ceramic (IPS e.max CAD) and zirconia-based ceramic materials (IPS e.max ZirCAD) were used. The experimental results indicated that the impact energy of ProCAD decreased with an increase in soaking time, but not for IPS e.max CAD and IPS e.max ZirCAD. The impact energy of the zirconia system was higher than leucite-reinforced and lithium disilicate-based ceramic systems. When subjected to preformed 0.5 mm U-shape notch on the bar specimen of 3 mm thick, the impact energy of the all-ceramic restorations revealed a markedly reduction of about 80%–90%, almost irrespective of dental compositions, which indicated the effect of flaw to a great degree. No statistically significant influence (p > 0.05) of pH values (4, 7 and 9) on impact energy was found for each group. It is concluded that the no matter which all-ceramic materials were used, it was appreciably sensitive to the presence of notches. The ceramic composition and microstructure have been shown to affect mechanical durability.

Investigation of salivary function and oral microbiota of radiation caries-free people with nasopharyngeal carcinoma.

Radiation caries have been reported to be correlated with radiotherapy-induced destruction of salivary function and changes in oral microbiota. There have been no published reports detailing patients who have remained radiation caries-free following radiotherapy for nasopharyngeal carcinoma. The aim of this study was to investigate the relationship between salivary function, oral microbiota and the absence of radiation caries. Twelve radiation caries-free patients and nine patients exhibiting radiation caries following irradiated nasopharyngeal carcinoma were selected. V40, the dose at which the volume of the contralateral parotid gland receives more than 40 Gy, was recorded. Stimulated saliva flow rate, pH values and buffering capacity were examined to assess salivary function. Stimulated saliva was used for molecular profiling by Denaturing Gradient Gel Electrophoresis. Mutans streptococci and Lactobacilli in saliva were also cultivated. There were no significant differences in V40 between radiation caries-free individuals and those with radiation caries. Compared with normal values, the radiation caries-free group had significantly decreased simulated saliva flow rate, while there were no significant differences in the saliva pH value and buffering capacity. Similar results were observed in the radiation caries group. There was no statistical difference in microbial diversity, composition and log CFU counts in cultivation from the radiation caries-free group and the radiation caries group. Eleven genera were detected in these two groups, among which Streptococcus spp. and Neisseria spp. had the highest distribution. Our results suggest that changes in salivary function and in salivary microbiota do not explain the absence of radiation caries in radiation caries-free individuals.

The influence of saliva pH value on the retention and durability of bar-clip attachments.

PURPOSEThe aim of this study was to compare the durability and retention of 4 types of attachments placed over computer aided design/computer aided manufacturing (CAD/CAM) titanium bars when subjected to different pH conditions.MATERIALS AND METHODSFour commercially available attachments were investigated: Hader Yellow, Hader Red, Ackerman Gold and Ackerman Stainless Steel. These attachments and Ackerman CAD/CAM titanium bars were placed in 2 vessels containing different artificial saliva solutions (pH 7/pH 4) at 37℃ for one month to simulate corrosion conditions, and they were then subjected to mechanical testing (5400 cycles of insertion and removal).RESULTSThe results revealed that there were significant differences in the average values of insertion/removal force due to the pH (F (1, 24)=9.207, P<.05) and the type of attachment (F (3, 24)=11.742, P<.05).CONCLUSIONMore acidic pH values were found to have a negative influence on the retention capacity of the attachments.