مجله دانشکده دندان پزشکی اصفهان
سال شانزدهم شماره 2 (پیاپی 71، تابستان 1399)

One of the most important issues after gingivectomy procedures is to shorten the wound healing period and decrease pain. One of the new techniques is the application of low-level laser, which has attracted attention because of the absence of side effects, appropriate equipment, and low treatment costs. This study aimed to evaluate the effect of low-level laser on accelerating the healing process after gingivectomy.

Twenty-two samples in 12 patients with gingival hyperplasia on their symmetrical teeth were included in this controlled clinical trial. After gingivectomy, 660-nm lowlevel laser was randomly applied to one side for 5 days. The contralateral side served as a control with no laser irradiation. The surgical areas were subjected to a plaquedisclosing solution (Mira-2-tone) to visualize the epithelium in the surgical area. Comparison of the surface areas between the LLLT-applied and control sites were made with Photoshop software after taking photographs. Data were analyzed with paired-sample t-test, independent-sample t-test, and ANOVA using SPSS 23. Statistical significance was defined at p value < 0.05.

There were no statistically differences between the stained surface areas of the LLLTapplied and control sites immediately after surgery and three days after surgery. However, the LLLT-applied sites exhibited significantly lower stained areas compared with the controls on the seventh and 15th postoperative days (p value < 0.001).

The results indicated that LLLT might enhance epithelialization and improve wound healing after gingivectomy.

In recent years, principles of ethics have been the focus of attention in public health research. One of the most important principles in this field is respect for the patients’ dignity. This study aimed to evaluate the respect for patients’ dignity by dental students and assistants.

In this descriptive-analytical study, 200 patients were randomly selected and divided into 4 groups in terms of their referral to the general and specialized dental clinics of Isfahan University of Medical Sciences, and Khorasgan Islamic Azad University. The questionnaire included demographic variables, educational level, and marital status of the patients, and questions on the observance of the patients’ dignity by the dentists. Data were analyzed with one-way ANOVA and t-test using SPSS 23 (α = 0.05).

The mean score of respect for the patients’ dignity by the dentists in the field of calling and addressing the patients showed significant differences between the four study groups (p value = 0.02). However, in general, there were no significant differences between the study groups in terms of the respect for the patients’ dignity by the undergraduate and postgraduate dental students (p value = 0.77).

Patients’ dignity has diverse components, with some factors improving them and with some others compromising them. Increasing the number of courses in medical ethics at dental schools can be effective in increasing respect for patients’ dignity.

Prior to crown lengthening surgery and/or restorative and prosthetic treatment, it is necessary to know the dimensions of the tooth biologic width. In different studies, the biologic width has been measured in different sites and teeth with a healthy periodontium. In this study, the biologic width was measured in different teeth of the mandibular and maxillary arches, and the effect of periodontal/gingival biotype on biologic width was evaluated.

This cross-sectional study was performed on 163 teeth in 12 subjects, including five males and seven females with an average age of 28 ± 4 years. After injecting the anesthetic agent, the dimensions of the biologic width were measured using a periodontal probe at six sites in all the existing teeth (except the third molars). Periodontal biotype was evaluated and categorized as thin or thick by observing transgingival shade of a probe. The data were analyzed with ANOVA and t-test using SPSS 19 (α = 0.05).

The average biologic widths in the molars, premolars, canines, and incisors were 1.90 ± 0.80, 1.72 ± 0.69, 155 ± 0.72, and 1.49±0.64, respectively. There was a significant relationship between the biologic width and the tooth type (p value = 0.000). However, there was no significant relationship between the biologic width and gingival biotype in six points and different sites of the mouth (p value > 0.08).

The biologic width dimension varies in different tooth types. The periodontal biotype has no effect on the biologic width dimension.

One of the most important goals of a morphological study is to determine the characteristics of non-metric dental traits, and different techniques are used to better achieve this goal. Since morphological diagnoses have been based on visual clinical findings to date, this study aimed to investigate the correlation of intraoral photography with clinical observations in the diagnosis of non-metric dental traits.

In this descriptive study, 80 students who were referred to the Morphology Department, Tehran Azad University Dental School, were evaluated. The students took part in the study voluntarily after the aims of the study were explained to them. Clinical examinations were carried out to evaluate Carabelli cusps, thick marginal ridges, and gingivopalatal fissures. A Canon EOS camera was used to take intraoral photos. The presence or absence of each trait in the two techniques was determined by Spearman’s correlation coefficient and their consistency (R2) was determined and evaluated statistically. The data were analyzed with SPSS 22 at a significance level of p value ≤ 0.05.

The correlation between the intraoral photography and clinical observations was calculated at 77% through Spearman’s correlation coefficient, which was acceptable; the consistency rate was calculated at 69%. The kappa coefficient between the two methods was estimated at 75.78%, which is considered excellent.

Since intraoral photography exhibited favorable correlation and consistency with clinical observations, it can provide valuable information on the diagnosis of nonmetric morphological traits.

Salivary gland reactive lesions are acquired, non-infectious, and non-neoplastic lesions. Often, direct trauma and salivary flow obstruction are reported to be the etiologic agents for these lesions. This study aimed to determine the frequency of salivary gland reactive lesions recorded in Isfahan Ayatollah Kashani and Al-Zahra Hospitals and Dental School during a 10-year period (2007-2016).

In this descriptive cross-sectional study, patients' records (n = 435) with a diagnosis of reactive lesions (mucocele, ranula, adenomatoid hyperplasia, necrotizing sialometaplasia, sclerosing polycystic adenosis, obstructive sialadenitis, mucus retention cyst, cheilitis glandularis) were investigated in Isfahan therapeutic centers from 2007 to 2016. Data analysis was performed with SPSS 22, using ANOVA and chi-squared test (α = 0.05).

A total of 435 samples of salivary gland reactive lesions were seen that accounted for 4.74% of oral biopsies, 28.5% of the whole oral reactive lesions, and 29.45% of salivary lesions. Mucocele (60.7%) had the highest frequency among salivary reactive lesions. Patients with mucocele and ranula were significantly younger than those with other salivary gland reactive lesions (p value < 0.001). The highest incidence of salivary glands reactive lesions was observed in the lower lip (56.6%).

Considering the prevalence of salivary gland reactive lesions among all the oral and salivary biopsies, recognizing the epidemiological characteristics of these lesions leads to better differential diagnosis of them from other oral and salivary lesions, such as salivary gland tumors, leading to their appropriate treatment.

The long-term success of indirect restorations depends on the clinical behavior of luting cements. In the oral environment, properties such as water sorption and solubility negatively affect the cements’ clinical performance over time, jeopardizing the restoration’s longevity. This study aimed to compare a self-adhesive resin luting cement with conventional resin-based and glass-ionomer luting materials in terms of water sorption (WS), solubility (WSB), hygroscopic expansion (HE), and hardness (H).

In this experimental study, 15 discs (6×2 mm) were prepared for each group from a self-adhesive luting cement (Bifix SE), a conventional dual-cured resin cement (Bifix Q), a glass-ionomer luting cement (Meron), and a resin-modified glass-ionomer (Meron Plus) using a silicone mold. The specimens were placed on an oversaturated sodium sulfate solution in a sealed chamber. Water sorption was evaluated after three weeks. Water solubility was calculated using the formula WSB = (M1-M3/V). Hygroscopic expansion was calculated using the formula He = v1-v2 in which the volume values were determined by pycnometry; Then, Vickers hardness test determined the hardness of the material before and after water sorption. The data were analyzed with ANOVA and Tukey HSD tests using SPSS 22 (α = 0.05).

Water sorption was significantly different between the four materials at different time intervals (p value < 0.001). Water solubility and hygroscopic expansion were significantly different between the four groups (p value < 0.001). Changes in hardness were not significantly different between the groups (p value = 0.099).

Both glass-ionomer cements were more prone to WS and WSB than resin cements. Bifix SE exhibited no water solubility; however, it was the most susceptible to hygroscopic expansion. Bifix QM exhibited the best behavior in terms of water sorption, solubility, and expansion due to water sorption. There was no statistically significant difference in hardness between all the materials before and after water sorption.

Since the matrix functional theory is critically important in explaining craniofacial growth and development, it is necessary to evaluate the relationship between the function of masticatory muscles, including the masseter muscle, and craniofacial growth and development, especially in the vertical dimension. This study aimed to evaluate the relationship between the masseter muscle size and the vertical dimensions of the face and mandible using computed tomography scanning.

In this analytical-descriptive study, three-dimensional CT scan facial images of 190 patients (men and women) were evaluated. Then measurements were made on two sides (left and right) with Workstation software. The width of masseter muscle was measured on the axial view, and its length and thickness were measured on the coronal view. The ramus height was measured on both sides, and the face vertical dimension was measured in the anterior and posterior areas. At the end of the measurements, no significant difference was observed between the two sides of the face. The data were analyzed with t-test and Pearson’s correlation coefficient using SPSS 22 (p value < 0.05).

The mandibular ramus length showed a significant difference between the two genders (p value < 0.0001), with males exhibiting a longer ramus compared to women. There was a direct and significant correlation between mandibular ramus length and the masseter muscle width, length, and thickness, in all the subjects (p value < 0.0001). Investigation of the correlation between the vertical dimension of the face and masseter muscle dimensions and the palatal and mandibular plane angles (p value = 0.676 (and the inclination of the mandibular plane in all the patients showed a direct but non-significant correlation (p value = 0.993).

Changes in the masseter muscle dimensions affects the skeletal size, craniofacial morphology, and skeletal angles.

Hyoid bone is a solitary bone, which is composed of a main body and two pairs of horns (greater, and lesser). This bone has an important function in respiration, swallowing, and speech. This study aimed to define the morphology and the frequency of fusion of hyoid bone and its relationship with age and sex on CBCT images.

In this cross-sectional descriptive analytical study, the CBCT images of 163 patients (92 females and 71 males) were analyzed using Type I OnDemand 3D software. In the axial cross-sections, the thickness and length of the hyoid body was measured; in coronal cross-sections, hyoid bone height was measured; and on the thick axial crosssections, the angle between the hyoid bone greater horn and the hyoid bone body midline was measured. The body and greater horn were classified into four categories in terms of fusion (non-fusion with a distance > 2.5 mm, non-fusion with a distance < 2.5 mm, partial fusion and complete fusion). The data were analyzed with Kolmogorov-Smirnov, chi-squared, and Fisher’s exact tests, paired t-test, and Kruskal-Wallis nonparametric test using SPSS 25 (α = 0.05).

In 79.7% of the patients the fusion was similar on both sides (p value = 0.806). There was no significant difference in hyoid bone fusion morphology between male and female groups and between the two sides (p value = 0.977). The most and least frequent types of hyoid bone fusion were type II (non-fusion with a distance < 2.5 mm) and type III (partial fusion), respectively. With the exception of the 10-19 year age group, type II category was the most common type, while type I was the most common in the 1–19-year age group. Hyoid bone fusion morphology varied significantly between the different age groups (p value < 0.05). Hyoid bone size (thickness, length, and height) was greater in men compared to women (p value < 0.05); however, the angle exhibited no significant difference between the male and female subjects (p value = 0.591). Of all the hyoid bone dimensions, only the length of its body was significantly different between the different age groups (p value < 0.05).

With advancing age, the distance between the body and the greater horn of the hyoid bone decreased, and its fusion frequency increased. Only the hyoid body length was different between the different age groups, and the other hyoid bone dimensions were the same. All the hyoid bone dimensions were greater in men compared to women, with the exception of the angle. It is possible to differentiate males from females based on the above-mentioned parameters. CBCT can help reconstruct the hyoid bone using its multiplanar reconstruction with lower radiation.

The tension-type headache (TTH) is the most common type of headache across the world with the greatest socioeconomic impact on patient’s life in comparison with other primary headaches. Salivary α-amylase could reflect changes associated with stress in the body. The present study investigated the relationship between stress and frequent episodic tension-type headache by measuring the salivary α-amylase levels.

In this case- control study, 90 females in two groups, a case group with 45 females with frequent episodic TTH and a control group with 45 healthy females were enrolled. The Hamilton stress questionnaire was completed in the two groups to examine the level of stress. Then, salivary α-amylase levels were measured. The data were analyzed with SPSS 18 using t-test and Mann-Whitney test (α = 0.05).

The mean salivary α-amylase activity levels and mean Hamilton questionnaire scores in the case group were significantly higher than those in the control group (p value = 0.001). In addition, there was a significant correlation between the salivary α-amylase activity and Hamilton questionnaire scores in the case (p value = 0.002) and control (p value= 0.001) groups.

According to the result of the present study, salivary α-amylase levels can be an appropriate marker for assessing anxiety in patients with frequent episodic tensiontype headache.

Abutment dimension is one of the most important factors affecting the retention of implant-supported restorations. Thick abutments have the advantages of providing a thicker outer body wall and more surface area for retention. This study aimed to determine the effect of abutment dimension on the retention of implant-supported restorations.

Forty implant analogs were mounted in auto-polymerizing acrylic resin blocks with the use of a surveyor in this in vitro study. Forty titanium abutments (7 and 5.5 mm in height, and 3.5 and 4.3 mm in width) were placed on each implant analog using 30N.cm torque. The crowns were cemented with temporary cement. All the specimens were stored under 100% relative humidity at 37ºC for 48 h prior to testing. Each crown underwent a tensile force with increasing force in a universal testing machine at a crosshead speed of 0.5 cm/minute, and the tensile strength was recorded (N). The data were analyzed with two-way ANOVA using SPSS 23.

An increase in abutment height significantly increased the tensile strength (p value = 0.03). An increase in the abutment width decreased the tensile strength, but it was not significant (p value = 0.41). There was a direct and significant correlation between the abutment height-to-width ratio and restoration retention (r = 0.343, p value = 0.01). There was a direct but poor correlation between the abutments total surface (abutment height*abutment diameter) and retention (r = 0.185, p value = 0.127).

Increased abutment height and height-to-width ratio had a more positive effect on retention than increased total surface area provided by increased width.

Dentists are effective in motivating and helping patients quit smoking. Considering the importance of this subject, this study aimed to assess the attitudes and performance of dentists in Isfahan in relation to tobacco-cessation interventions in 2018.

This study used a quantitative and survey approach. The statistical population of the study consisted of dentists in Isfahan (n = 100), who were selected using the cluster sampling method. The data collection tool was the standard Patel questionnaire. The validity and reliability of this questionnaire have been confirmed abroad. Confirmation of the translated version was made by the Faculty members, and its reliability was confirmed with Cronbach's alpha coefficient (0.87). Descriptive statistics (frequencies, percentages, and means) and deductive statistics (independent t-test, one-sample t-test and Spearman’s correlation coefficient) were used. The data were analyzed with SPSS 22 (α = 0.05).

Most dentists (i.e., 72%) were male and the rest were female. The majority of the subjects (i.e., 52%) were < 35 years of age. The lack of acceptance by the patients, lack of interest, and lack of information and sufficient training (with means values of 2.97, 2.86, and 2.72) were the most important preventing factors. The mean scores of attitude and practice of the dentists were moderate to poor. Gender and age affected attitudes and practice.

The dentists in the present study exhibited moderate to poor attitudes and performance. It appears it is necessary to offer training courses on counselling in relation to smoking cessation to improve the dentists attitudes and performance in this area.

Xerostomia is a condition in which saliva is not secreted in sufficient amounts. The prevalence of xerostomia is 25-40%. Osteoporosis is a common, yet insidious disease, the early diagnosis of which is of critical importance. This study aimed to investigate the relationship between osteoporosis and xerostomia and the number of remaining teeth in postmenopausal women in Isfahan.

This case-control study was performed on 129 postmenopausal women >50 years old, referring to an osteoporosis center in Isfahan in 2018. The subjects were divided into three groups based on bone density. The first group included 38 healthy subjects; the second group included 56 patients with osteopenia; and the third group consisted of 35 patients with osteoporosis. Xerostomia was determined by a standard questionnaire, and the number of teeth was obtained by clinical examination. The data were analyzed with SPSS 24, using independent-sample t-test, Mann-Whitney test, ANOVA, and Pearson’s correlation coefficient (α = 0.05).

According to the results, there was no significant relationship between osteoporosis and xerostomia (p value = 0.372). However, there were significant relationships between osteoporosis and the number of remaining teeth and xerostomia (p value < 0.01).

There was no significant relationship between osteoporosis and xerostomia in postmenopausal women > 50 years of age with osteoporosis; however, there was a significant relationship between osteoporosis and the number of missing teeth.

Internal root resorption is a pathologic process, which follows dental pulp inflammation. In this process, multinucleated clastic giant cells resorb the root dentin. Several etiologic factors, including orthodontic forces, trauma, the heat generated during cavity preparation, and caries, are held responsible for this process. In case of delayed diagnosis and intervention, this process might lead to root perforation and formation of a periapical lesion, which might complicate further treatment.

Non-surgical root canal treatment was performed on a 35-year-old female with tenderness to percussion after the diagnosis of internal root resorption with the CBCT technique. The resorption had caused root perforation. The patient was scheduled for a one-year follow-up.