The effects of polymerization mode and layer thickness on monomer released from bulk fill composite resins.

BACKGROUND: Residual monomers released from composite resins have cytotoxic, mutagenic, and estrogenic effects. Mode of polymerization and application thickness are important for monomer release. AIMS: The aim of this study was to investigate the effects of different modes of a third-generation light-curing unit (LCU) and layer thickness on residual monomer released from two different bulk-fill composite resins. A total of 80 samples were prepared for each bulk-fill composite using a mold. Each bulk-fill composite was divided into four groups according to polymerization mode (standard and extra power) and layer thickness (2 and 4 mm). In addition, four groups were divided into four subgroups according to time periods (1 h, 24 h, 3 days, and 7 days). METHODS AND MATERIAL: The samples were polymerized with VALO LED device. The amount of residual monomer was measured with High-Performance Liquid Chromatography (HPLC). All statistical analyses were processed using SPSS Version 23.0. The normal distribution of data was confirmed using Kolmogorov-Smirnov Normal Distribution Test and Shapiro-Wilk Normal Distribution Test. When the distribution was normal, parametric tests, Student's t test and one-way ANOVA, were used. When the distribution was not normal, non-parametric tests, Mann-Whitney U test, and Kruskal-Wallis testwere used. RESULTS: It was found that the standard mode of LCU produced lower amounts of TEGDMA, Bis-GMA, and UDMA in both composite materials. In addition, when the layer thickness increased, TEGDMA, Bis-GMA, and UDMA releases increased, too. CONCLUSIONS: This study revealed that the amount of residual monomers released from bulk-fill composites was affected by layer thickness and polymerization time.

Effects of diode laser irradiation on dental pulps in rats.

OBJECTIVES: To evaluate the effects of different power densities of diode laser on dental pulps in rats. BACKGROUND: In this study, we used the maxillary central incisors (n=80) of the 40 adult male Wistar albino rats. METHODS: Rats were randomly divided into four groups according to power densities of diode laser (n=10). Histopathological changes in pulp and height of odontoblast layer were examined . All data were compared statistically using Mann‒Whitney U (Bonferroni) test, p<0.05. RESULTS: G2 displayed slight histolopathologic alterations such as odontoblast cell disorganization and irregularities in cell extensions. Alterations were more prominent in the G3 than G2. Although the lowest odontoblast layer was measured in the G4, the difference in height of odontoblast layer among the groups was not found to be statistically significant. CONCLUSION: It was concluded that the use of diode laser caused changes at the cellular level in histological examination and may induce the formation of tertiary dentin by influencing the secretory activity of odontoblasts. As long as used in accordance with the recommended procedure, the diode laser can be safely used in dental hard tissues (Tab. 1, Fig. 4, Ref. 15).

Survival of avulsed permanent incisors in children following delayed replantation.

BACKGROUND: Replantation of avulsed teeth is an invasive treatment approach where patient cooperation is required after the risks are explained to the patient or family. Although replantation of an avulsed permanent teeth is an accepted treatment approach, the long-term prognosis of the replanted teeth is still controversial. This report describes the survival of delayed replanted 15 incisors that was stored in unfavorable conditions after avulsion. MATERIALS AND METHODS: Nine patients, aged 8-12 years, were referred to the Inonu University, Pediatric Dentistry Department with traumatically avulsed incisors. The parents were informed about the possible complications of a delayed replantation. RESULTS: Forty percent of the teeth were splinted with flexible orthodontic wire and composite. The follow-up periods were varied from 24 to 48 months. The mean follow-up periods were 33.3 ± 8 months. 40% of the teeth were retained in the mouth for at least 3 years and contributed to alveolar bone development. In these cases, the most common complication (9 teeth, 60%) was replacement root resorption. Two of the 15 teeth which had wide open apices, continued to the root development. CONCLUSION: In this study, replanted teeth were retained in the mouth for at least 2 years and contributed to the patient's development. Therefore, this study has shown that delayed replantation of an avulsed tooth for a child is still worthwhile, even in cases of poor prognosis where the tooth had extended extra-alveolar dry storage. We believe that delayed replantation should be done because of its importance for the child's jaw and facial development.

Finite element analysis of thermal stress distribution in different restorative materials used in class V cavities.

PURPOSE: Cervical lesions are restored with class V preparation. The aim of this study was to use a three-dimensional finite element method to carry out a thermal analysis of the temperature and stress distributions of three different restorative materials used for class V cavities of maxillary molar teeth. MATERIALS AND METHODS: A maxillary left first molar tooth was modeled and a class V cavity was prepared on the cervical 1/3 of the buccal surface. This cavity was restored with three different materials (Group I: Resin composite, Group II: Glass ionomer cement, and Group III: Amalgam). Loads of 400 N were applied at an angle of 90° to the longitudinal axis of the tooth on the restorative material at 5 and 55°C temperatures. Von Mises and thermal stress distributions were evaluated. RESULTS: In all groups, the von Mises stress values increased with temperature. The highest von Mises stress distribution was observed at 55°C in Group II (144.53 MPa). The lowest von Mises stress distribution was observed at 5°C in Group III (70.81 MPa). CONCLUSION: Amalgam is the most suitable restorative material for class V restorations because of minimal stress distribution.

Dental findings in Hamamy syndrome.

This paper highlights features of dental rehabilitation of patients with Hamamy syndrome. A 10-year-old boy patient with Hamamy syndrome reported pain in the maxillary left central incisor, and all mandibular incisors. Intraoral clinical and radiographical examination showed enamel hypoplasia, severe dilacerated maxillary left central incisor and mandibular incisors, malocclusion, delayed eruption of teeth, taurodontism, and loss of lamina dura. Root canal treatment, strip crown and composite restorations were performed.

A two-year clinical evaluation of glass ionomer and ormocer based fissure sealants.

UNLABELLED: The objective of the present study provides further data comparing retention, marginal integrity and caries preventive effects of two fissure sealants (glass ionomer based; GC Fuji VII Capsule [Fuji VII] and ormocer based; Admira Seal [AS]) in children. This study was designed as a randomized single-blind clinical trial. The permanent first molars (PFMs) of 50 children, 7-13 years of age (mean age: 8.9 +/- 1.3 years), were sealed with a split-mouth design. Fissure sealants applied to the PFMs according to the manufacturer's recommendations by one pediatric dentist. Clinical evaluation of the sealants was carried out to record retention, marginal integrity and presence of caries at 6, 12, 18 and 24 months after placement by the other pediatric dentist. Kaplan-Meier survival analysis and Cox's regression models were used to estimate the probability of two sealants success. RESULTS: Alpha and Bravo retention rates at the end of follow-up were 13% and 80% for Fuji VII and 3% and 83% for AS, respectively. For retention and marginal integrity between fissure sealants was found similar survival rates (p > 0.05). After 24 months, presence of caries was 16% for Fuji VII and 32% for AS (p < 0.05). CONCLUSION: Fuji VII and AS exhibited similar retention and marginal integrity during 24 months. However Fuji VII was showed better results than AS for caries preventive effect. Consequently, Fuji VII sealants may be a better choice for preventing occlusal caries.

Evaluation of different sterilization and disinfection methods on commercially made preformed crowns.

The aim of this study was to evaluate the changes caused by different sterilization or disinfection methods on the vestibular surface of four commercially made preformed crowns using stereomicroscopy and scanning electron microscopy (SEM). Preformed crowns (NuSmile Primary Anterior Crown (NSC), Kinder Krowns (KK), Pedo Pearls (PP) and polycarbonate crowns (PC)) were sterilized and/or disinfected by one of the following techniques: no sterilization or disinfection (G1 control group); steam autoclaving at 134 degrees C (30 psi) for 4 min (G2); steam autoclaving at 134 degrees C (30 psi) for 12 min (G3); steam autoclaving at 121 degrees C (15 psi) for 30 min (G4); and ultrasonication in a bath containing 4% Lysetol AF for 5 min at room temperature (chemical disinfection) (G5). Scanning electron micrographs of the crowns were taken before and after their sterilization or disinfection. The changes on the vestibular surface were then scored for the presence or absence of crazing, contour alteration, fracturing, and vestibular surface changes. The data were analyzed statistically using the chi-square test. No changes were observed before and after sterilization or disinfection in the stereomicroscopic evaluation of the vestibular surface of the crowns. However, all methods in which steam autoclaving was used to sterilize the crowns caused significant (P < 0.05) crazing and contour alterations of the vestibular surface of the crowns when they were examined by SEM. Chemical disinfection using an aldehyde-free disinfectant is the preferred method of disinfection for crowns that have been used previously in other dental patients.

Volume-weighted mean nuclear volume in renal cell carcinoma.

OBJECTIVES: Tumor grade and stage are the most important prognostic parameters for renal cell carcinoma (RCC). The value of histologic nuclear grading, however, is impaired by the inconsistency of pathologists' observations. Estimate of volume-weighted mean nuclear volume (MNV), based on a stereologic method, is correlated with prognosis of bladder, prostate, and endometrial cancer. In this study, we investigated the prognostic value of stereologic estimation of nuclear volume in RCC. METHODS: This study included 62 patients with RCC who underwent radical nephrectomy between 1989 and 1996. Patients were evaluated in two groups: patients with locally advanced and/or metastatic disease were part of the poor prognosis group and patients with localized disease were part of the good prognosis group. Unbiased estimates of MNV were compared with histologic grade, tumor stage, and growth pattern according to Thoenes classification. Group means were compared using the nonparametric Kruskal-Wallis one-way analysis of variance. Univariate analysis of the data was performed for MNV and time to death, metastasis, local recurrence, and disease-free survival by paired sample t test. For categorical variables, Pearson's correlation test was used for statistical analysis. RESULTS: There was no correlation between MNV and patient sex, age, tumor stage, and growth pattern. MNV showed a trend to be higher in sarcomatoid and chromophilic cell types than in chromophobe and clear cell types (P < 0.05). MNV values were significantly higher with increasing grades but no MNV cutoff levels could be defined. The MNV values were not different between localized and locally advanced and/or metastatic disease. CONCLUSIONS: Our results indicate that estimates of MNV are not useful for predicting disease outcome. Further studies are needed to set up reproducible intervals of tumor dedifferentiation that could be carried out in routine practice for predicting progression.

Prevention of posterior capsule opacification by intraoperative single-dose pharmacologic agents.

PURPOSE: To determine whether an intraoperative single dose of dexamethasone, diclofenac, ethylenediaminetetraacetic acid (EDTA), a combination of EDTA and RGD peptide (arginine-glycin-aspartic acid sequence), or mitomycin-C (MMC) is a pharmacological means of preventing or reducing the development of posterior capsule opacification (PCO). SETTING: Department of Ophthalmology, Celal Bayar University, School of Medicine, Manisa, and Department of Pathology, Dokur Eylül University, School of Medicine, Izmir, Turkey. METHODS: Fifty-four rabbits were randomly divided into 6 groups. Dexamethasone (4 mg/cc), diclofenac (2.5 mg/cc), EDTA (8 mg/cc), a combination of EDTA and RGD peptide (2.5 mg/cc), or MMC (0.04 mg/cc) was given, 0.1 cc by hydrodissection and 0.9 cc into the capsular bag after phacoemulsification. The sixth group served as a control group. After 3 months, the PCO was graded clinically and the proliferation of lens epithelial cells (LECs) was evaluated histologically. RESULTS: The drugs were significantly effective in preventing PCO compared with the control (P <.005). Dexamethasone had a weaker effect than the other drugs. In histological analysis, although monolayer LECs in the dexamethasone and diclofenac groups were observed, there was no proliferative activity on the posterior capsules in the EDTA, EDTA+RGD, and MMC groups in contrast to the multilayer cells in the control. CONCLUSIONS: Intraoperative single-dose application of EDTA, EDTA+RGD peptide combination, and MMC significantly prevented the development of PCO in rabbit eyes. Diclofenac was less effective but also reduced PCO. Although dexamethasone did not prevent the proliferation of LECs, it decreased PCO clinically.

The effect of verapamil on the prevention of ischemia/reperfusion injury in the experimental retroperitoneoscopic donor nephrectomy model.

BACKGROUND: This study investigated the effect of intravenous administration of verapamil in prevention of the injury caused by free oxygen radicals generated in a rabbit retroperitoneoscopic donor nephrectomy model. METHODS: Twenty-four adult New Zealand rabbits were divided into four groups. In group I, balloon dissection of the left retroperitoneal space was performed. In group II, CO2 at 10 mmHg was applied for 3 hours after the balloon dissection. In group III, laparotomy was performed, the left renal pedicle was clamped for 3 min, and the clamp was removed 5 min before nephrectomy. In group IV, 2 min before the attempt 0.2 mg/kg verapamil was given intravenously, and the same procedure was employed as in group III. Nephrectomy was performed after each experiment. The concentrations of malonyl dialdehyde (MDA), reduced glutathione (GSH), and protein carbonyl content were measured in renal tissue samples as markers of oxidative stress. RESULTS: Pneumoretroperitoneum (Prp) promoted oxidative stress in renal tissues, with an increase of MDA and protein carbonyl content. The verapamil- pretreated group (group IV) showed statistical significantly lower values of MDA and protein carbonyl content when compared with group II and III (p < 0.05), whereas tissue GSH concentrations were unchanged in all groups. CONCLUSIONS: Our study showed that Prp causes increased oxidative stress in renal tissue. Warm ischemia lasting 3 min did not exert an additive effect on Prp-associated oxidative stress. Verapamil reduces the oxidative stress markers caused by Prp.

Religious fasting and intraocular pressure.

PURPOSE: To determine the effects of Islamic religious fasting on intraocular pressure. METHODS: The authors measured diurnal intraocular pressure values during religious fasting and 1 month later in 38 healthy male volunteers with a mean age of 22.4 +/- 2.7 years. Body weight and urine specific gravity were determined to assess the extent of dehydration caused by fasting. RESULTS: Although each patient had weight loss (0.1-1.4 kg) representing a slight dehydration caused by fasting, intraocular pressure values were not statistically different between fasting and nonfasting periods (P > 0.05). CONCLUSION: Fasting did not alter diurnal intraocular pressure values in healthy people.

Renal effects of carbon dioxide insufflation in rabbit pneumoretroperitoneum model.

To determine the effects of carbon dioxide insufflation on renal function in a pneumoretroperitoneum model, 24 adult New Zealand rabbits were divided into four groups, six rabbits in each. The first group underwent a 2-hour CO2 insufflation at a pressure of 10 mm Hg in the retroperitoneal space after balloon dissection. In another group, the same procedure was maintained for 4 hours. In the sham-treated groups, the procedure was similarly carried out but without CO2 insufflation. In all four groups, serum and urine creatinine concentrations and renal artery and renal vein blood flow rates were determined separately at the beginning and at the end of the procedure and at 24 hours. Urine output was also recorded at the end of the procedure and at 24 hours. The serum creatinine in the 2- and 4-hour study groups had increased significantly at the end of the procedure, accompanied by a significant decrease in the urine creatinine value. Renal artery and renal vein blood flow rates and urine output were reduced in both groups during the study. All changes in the serum and urine creatinine, renal artery and vein flow rates, and urine output was more pronounced in the 4-hour group. All measures returned to their prestudy values by 24 hours. Pneumoretroperitoneum causes reversible renal dysfunction, which becomes more pronounced with prolonged insufflation. Further research is needed to show the impact of our findings in high-risk patients undergoing retroperitoneoscopic surgery.

Are obstructing ureteral stones more difficult to treat with extracorporeal electromagnetic shock wave lithotripsy?

In situ extracorporeal shock wave lithotripsy (ESL) has increasingly become accepted for the treatment of ureteral stones. However, treatment success is negatively affected by stone impaction or associated urinary obstruction. In order to assess the impact of obstruction on the outcome of in situ ESL, we reviewed the results in 503 patients treated in this way. The presence and severity of urinary obstruction was defined prior to ESL, being classified as no or mild obstruction (Group I) and moderate or severe obstruction (Group II). The stone-free rate in the nonobstructed group was 90%, whereas it was 85% in the obstructed group (P > 0.005). While all of our patients were treated on an outpatient basis, two patients in Group I and four patients in Group II required hospitalization with the diagnosis of pyelonephritis. All six patients were treated successfully with appropriate measures. No other serious complication occurred that required hospitalization. We conclude that urinary obstruction does not affect stone disintegration or passage and suggest that in situ ESL should be the treatment of choice in ureteral stones.

Does respiratory gating improve extracorporeal shockwave lithotripsy results?

The reliability and efficacy of extracorporeal shockwave lithotripsy (SWL) has been established in urinary stone disease. Its combination with respiratory gating might be a useful method to increase the effectiveness of treatment and reduce the number of shocks required. For this purpose, the results of SWL combined with respiratory gating were compared with those of SWL without gating. There was no difference in the stone-free rates of the two groups or in the complication rate. It is concluded that this method neither decreases the number of shockwaves needed nor increases the effectiveness of SWL.

Ocular findings in a measles epidemic among young adults.

PURPOSE: To present ocular findings in a measles epidemic outbreak among young adults. METHODS: Ophthalmic lesions in an unselected group of 61 young military personnel with measles were followed. Eighteen of the patients had symmetric keratitis in both eyes. They were treated with diclofenac sodium eyedrops qid in the right eye, while the left eye was observed untreated. The disappearance of the corneal lesions in both eyes was compared. RESULTS: Forty patients (65.6%) had measles conjunctivitis with bulbar and tarsal conjunctival hyperemia. Five (8.2%) had increased mucous secretion. Thirty-five (57.4%) had superficial punctate corneal epithelial and subepithelial lesions which stained with fluorescein. Ten patients had corneal lesions without evident conjunctival pathology. Fourteen patients had subconjunctival hemorrhages, 12 of whom had bilateral lesions mostly in the superonasal quadrant. The time to disappearance of corneal lesions was 4.5+/-3.2 days in the diclophenac-treated right eyes, and 4.1+/-3.8 days in the left eyes. We did not observe a significant difference in the healing time between the two eyes (p = 0.75). CONCLUSION: Measles did not cause major ocular complications in healthy patients. Keratitis was unresponsive to diclophenac sodium eyedrops with respect to healing time and end result.

Effects of betaxolol and latanoprost on ocular blood flow and visual fields in patients with primary open-angle glaucoma.

PURPOSE: To evaluate the effects of betaxolol and latanoprost on ocular blood flow and visual fields in patients with primary open-angle glaucoma (POAG) by means of an observer-masked, prospective clinical study. METHODS: Thirty-two patients with newly diagnosed POAG were included in the study. The patients were randomized into two groups. The first group was treated with betaxolol 0.50% twice daily and the second group with latanoprost 0.005% once daily. Baseline and posttreatment examinations on the first and third months of treatment included intraocular pressure (IOP) measurement, automated visual field testing, and ocular blood flow assessment. For evaluation of visual fields, mean defect and pattern standard deviation indices were used. Ocular blood flow was assessed by means of color Doppler imaging of the central retinal artery (CRA) and the temporal short posterior ciliary artery (PCA). For each vessel, peak systolic (PSV) and end-diastolic (EDV) blood flow velocities were measured and resistivity index (RI) calculated. RESULTS: After exclusion of one noncompliant patient, the study was completed with 31 eyes of 31 patients. Both drugs significantly reduced IOP (p<0.05). The mean IOP lowering effect of latanoprost was significantly higher than that of betaxolol (p=0.03). Visual field indices exhibited no significant changes in either group (p>0.05). There were no significant changes in PSV or EDV measurements of CRA or PCA in either group (p>0.05). RI decreased in both CRA and PCA with both drugs. The mean changes between baseline and 3 month blood flow measurements were not significantly different between betaxolol and latanoprost (p>0.05). CONCLUSIONS: Over a treatment period of 3 months, both betaxolol and latanoprost tended to improve ocular blood flow without one of them being superior to the other. The results suggest that the direct (non IOP-dependent) influence on ocular circulation is better for betaxolol than for latanoprost. In addition, neither drug caused significant generalized improvements in visual fields during this period.

Fluorescein dye disappearance test in patients with different degrees of epiphora.

PURPOSE: To assess the diagnostic efficacy of a modification of the fluorescein dye disappearance test (DDT) in patients with different degrees of epiphora. METHODS: DDT was performed by instilling a drop of 2% fluorescein in the eye. Schirmer tear test strips were placed in the lower conjunctival fornix, after 3 and 10 minutes. The colour dilution on the strips was compared to a scale with known standards and the most closely comparable colour dilution was chosen and recorded as the visual scale test (VST) grade of the strip. The grey-scale value (GV) of each strip was calculated by computer image analysis. The control group comprised 44 patients, mean age 44.8 years (SD 7.5, range 30-60). There were 13 patients in group 1 with moderate epiphora; mean age was 44.2 years (SD 9.5, range 30-60). There were 17 patients in group 2 with severe epiphora; mean age was 48.3 years (SD 7.7, range 37- 60). RESULTS: VST and GV differed significantly between controls and group 1 patients at 3 minutes (p=0.002, p=0.001), and between controls and group 2 patients at 3 minutes (p<0.001, p<0.001). There was no difference between groups 1 and 2 patients in VST and GV at 3 minutes. The differences were highly significant between controls and group 1 at 10 minutes (p=0.001, p=0.007), and between controls and group 2 at 10 minutes (p<0.001, p<0.001). The differences in GV and VST between groups 1 and 2 were significant at 10 minutes (p=0.026, p=0.018). CONCLUSIONS: This modified DDT permits identification of different degrees of epiphora in a non-invasive manner, it can therefore be used to evaluate the outcome of different treatment strategies.

Regressed retinopathy of prematurity in children aged 5-8 years in Sivas, Turkey.

In this present study regressed retinopathy of prematurity has been investigated in children born prematurely (< 2300 g birth weight and < 34 weeks gestational age) in Sivas, Turkey during January 1989-January 1992. At the age of 5-8 years, 55 children born prematurely were examined; eye fundus information could be obtained by indirect ophthalmoscopy in all of them. The frequency of regressed retinopathy of prematurity was 35.45 percent for the whole group. Severe forms with optic atrophy, dragged optic disk, vitreoretinal scarring, retinal traction and temporal avascular retina were seen in 13.63 percent of cases. Moderate forms with pigmentary changes, vitreoretinal interphase changes and lattice degeneration were seen in 21.81 percent of cases. While the severe and moderate regressed premature retinopathy findings in premature children with gestational ages of 30-34 weeks were observed to be 12.0 and 14.0 percent, respectively, those in the 25-29 week-gestational-aged premature children were determined to be 5.0 and 28.33 percent, respectively. Although the incidence of both severe and moderate regressed premature retinopathy was higher in the 25-29 week gestational-aged group when compared to that of the 30-34-week-gestational-aged group, the difference was not found to be statistically significant (p > 0.05). In conclusion, premature retinopathy should not only be followed up in the early stage with active changes but also later in infancy and childhood because of regressed premature retinopathy findings that may require treatment.

Open stone surgery: is it still a preferable procedure in the management of staghorn calculi?

We reviewed 43 patients with staghorn calculi to determine the effectiveness of various treatment modalities such as extracorporeal shock wave lithotripsy (ESWL) monotherapy, ESWL and percutaneous nephrolithotomy (PCNL) combined therapy, and open stone surgery. While ESWL monotherapy and ESWL+PCNL were performed in 25 and 8 patients, respectively, 10 patients underwent open stone surgery. Of the 25 patients treated with ESWL, 8 were stone-free, whereas 4 out of 8 patients treated with ESWL+PCNL and 8 out of 10 patients treated with open surgery were stone-free. The complications of ESWL monotherapy consisted of pyelonephritis in one patient, and stone street formation in three. In the group of ESWL+PCNL, one patient developed pyonephrosis, and another perinephritic abscess. No serious complication was noted in patients who underwent open surgery, but an average of 525 ml of blood transfusion was required. We conclude that open stone surgery, although invasive, is still beneficial in the treatment of staghorn calculi.

Impacts of earthquake aftermath on indoor carbon monoxide levels in Turkish coffeehouses environment in duzce, Turkey.

BACKGROUND: In 1999, Duzce suffered two consecutive devastating earthquakes above magnitude 7 in August and November. In the present study, we aimed to evaluate the indoor air quality of coffeehouses by determining carbon monoxide (CO) levels and their contributing factors in coffeehouses built before and after the earthquake. METHODS: We conducted our study in 76 Turkish coffeehouses in Duzce in winter (November 2007-March 2008) during rush hours (18:00-23:00). The Turkish coffeehouses included in the study were evaluated under four categories based on smoking status and construction date. The characteristics of the coffeehouses, such as their CO levels and temperatures both indoors and outdoors, were all measured. These analyses were carried out with the SPSS 15.0 program. RESULTS: The CO levels in Turkish coffeehouses were above the values indicated as being safe by the WHO. While stoves and cooking equipment were determined to contribute to indoor CO levels, cigarettes were found to be the main source. Indoor CO levels at second hour were very strongly correlated (r: 0.84, P<0.001) (r: 0.91, P<0.001) with indoor CO levels at initial and first hour as well as with smoking status (r: 0.69, P<0.001); they were also moderately correlated with the room volume (r: 0.34, P<0.001) and construction materials (r: 0.31, P<0.001) of the coffeehouse. CONCLUSION: Elevated CO levels in Turkish coffeehouses indicate the possible presence of other pollutants, particularly when the main source is smoking. In such cases, both individuals and the whole of society are affected negatively in many ways. Therefore, smoking should be prohibited by law in Turkish coffeehouses and national awareness programs should be developed based on peoples' lifestyles. Moreover, the standards for construction and management of Turkish coffeehouses should be improved as well.