Journal of Dental School, Shahid Beheshti University of Medical Sciences

Objectives: An efficient, safe, affordable and easily accessible measuring instrument for quantitative assessment of bone prior to dental implant placement enables more accurate treatment planning. Costly imaging modalities are neither widely available, nor affordable for some patients. This study sought to assess the efficacy of a newly designed digital bone gauge for measurement of bone width with 0.1 mm accuracy in comparison with a digital caliper.

Methods: Using CATIA software, three-dimensional (3D) model of the instrument was designed and its experimental version was fabricated in two models and tested on an edentulous alveolar ridge model. The efficacy of the instrument was assessed by comparing the values obtained by the designed bone gauge with direct measurements made by a digital caliper. The buccolingual width of the edentulous ridge was measured at the crestal level and at 1, 2, 3 and 4 mm apical to the bone crest by the designed bone gauge and digital caliper. The intraclass correlation coefficient (ICC) of the values was calculated.

Results: Virtual and experimental models of the instrument were designed and patented. The designed instrument was successfully capable of measuring bone width with 0.1 mm accuracy. The ICC values at 1, 2, 3 and 4 mm apical to the bone crest and at all levels were calculated to be 0.973, 0.994, 0.997, 0.998 and 0.998, respectively.

Conclusion: The designed digital bone gauge can efficiently measure bone width at different levels with high accuracy. It can provide valuable and reliable information about bone width at initial clinical examination.

Objectives: Dental impressions are among the potentially infectious items in dentistry. Dental impressions are invariably contaminated with saliva or blood. Such fluids may contain viral or bacterial pathogens including Bacteroides, Fusobacterium, Porphyromonas and Prevotella. The aim of this study was to assess the effects of three different types of disinfectants on alginate impression materials after one, three and five minutes.

Methods: In this in vitro experimental study, 126 circular samples of alginate impression materials were contaminated with Staphylococcus aureus (S. aureus) and Pseudomonas aeruginosa and were then disinfected with 0.525% sodium hypochlorite, Deconex (Solarsept) and SeptiTurbo spray. Afterwards, the samples were wrapped in moist paper towels and kept in plastic bags for one, three and five minutes. Number of bacterial colonies was counted 24 hours after incubation. Negative and positive controls were included.

Results: After five minutes, 0.525% sodium hypochlorite showed the highest disinfection activity against S. aurous as it eradicated over 99.98% of the bacteria. Although the disinfecting agents showed non-significant results in eradicating S. aureus, SeptiTurbo was more effective in elimination of S. aurous . The disinfection activity of different agents increased with time.

Objectives: The purpose of this study was to evaluate the effect of low dose doxycycline and atorvastatin on gingival inflammation and alveolar bone loss in an experimental model of periodontitis in rats.

Methods: Forty male Sprague Dawley rats were divided into four study groups as follows: (I) experimental periodontitis control, (II) rats with periodontitis treated with low dose atorvastatin (10 mg/kg), (III) rats with periodontitis treated with low dose doxycycline (6 mg/kg) and rats with periodontitis treated with both doxycycline and atorvastatin. Periodontitis was induced by ligature placement around the upper left second molar foe seven days. The periodontitis group received saline, periodontitis/doxycycline group received doxycycline by oral gavage, periodontitis/atorvastatin group received atorvastatin by oral gavage and doxycycline/atorvastatin group received both drugs simultaneously (6 and 10 mg/kg, respectively) for 21 days after ligature placement. Then, the rats were sacrificed and their maxillae were removed, defleshed, and prepared for histopathological examination. Data were analyzed statistically by the Kruskal-Wallis test and Mann-Whitney U test at 5% level of significance and presented as frequency

Results: Using a combination of doxycycline and atorvastatin caused a significant decrease in gingival inflammation and alveolar bone loss (16.5%) and collagen degradation (13%) when compared to the control group (36.10% and 36.95%, respectively; P<0.001).

Conclusion: Low dose atorvastatin and low dose doxycycline synergically prevented alveolar bone loss and collagen degradation in ligature-induced periodontitis in rats.

Objectives: Diabetes mellitus is one of the most common chronic diseases that may cause irreversible complications. This disease can affect the salivary glands and oral health. Among physical and chemical alterations, changes in the pH and viscosity of saliva are particularly important. The aim of this study was to compare the pH and viscosity of unstimulated saliva in diabetic patients and non-diabetic controls.

Methods: In the present case-control study, three groups consisted of 36 controlled type 2 diabetic patients, 36 uncontrolled type 2 diabetic patients and 36 healthy controls were recruited and matched by age and sex. Their unstimulated cumulative saliva was collected for five minutes by the spitting method and the pH of samples was measured by a digital pH meter. The viscosity of saliva samples was assessed by comparing the sample displacement rate with that of control fluids at mm/10 seconds. Data were analyzed by SPSS version 20 via ANOVA and Bonferroni multiple comparisons test. P value less than 0.05 was considered statistically significant.

Results: A significant inverse correlation was found between the saliva pH and hyperglycemia (P<0.0001). A significant relationship was noted between viscosity and severity of diabetes mellitus (P<0.0001). The pH of saliva in uncontrolled diabetic patients was significantly lower than that of controlled type 2 diabetic patients and non-diabetic control group (P<0.05). The viscosity of saliva in diabetic patients with well and poorly controlled hyperglycemia was more than that of the control group (P<0.009 and P<0.0001, respectively).

Conclusion: Diabetes mellitus causes a reduction in saliva pH and increases the viscosity of saliva, which can cause qualitative and quantitative changes in the saliva and oral health.

Objectives: Since forgetfulness is the major cause of missed appointments, reminder systems can be used prior to appointments. The present study aimed to evaluate the efficacy of different reminders [e-mails, social networks, telephone, and short message service (SMS)] in order to reduce missed appointments by orthodontic patients.

Methods: Of a total of 751 active orthodontic patients, 379 were assigned to the reminder group and 372 to the control group. The former group was randomly divided into four subgroups who received a reminder 2 days before their appointments either by telephone, e-mail, SMS, or a message on Facebook. Patients allocated to the control group received no reminder. The percentage of missed appointments and the demographic characteristics of patients in each group were analyzed with the chi-squared test.

Results: The percentage of missed appointments was significantly higher in the control group (41.39%) than the reminder group (11.08%) (P<0.001). There was no difference in the attendance rate of patients among telephone, SMS, and e-mail groups. Missed appointments were insignificantly higher in patients whose parents had the highest educational level (P=0.8). In patients with low family income, the percentage of missed appointments was the lowest, but this difference was not statistically significant (P=0.5).

Conclusion: The study results indicated that sending reminders is an effective strategy to reduce missed appointments. E-mails and social networks can be employed to send reminders easily and cost-effectively and prevent missed appointments.

Objectives: Success of regenerative dental procedures highly depends on their acceptance by the clinicians; yet, little is known about dental residents’ attitudes regarding this new technology. The purpose of this study was to assess the knowledge and attitude of post-graduate dental students towards stem cells and regenerative dentistry as part of future dental treatments.

Methods: This cross-sectional survey was conducted on 84 third-year residents of various dental specialties. The questionnaire included demographics and professional status of the respondents, questions regarding their ethical beliefs and their clinical practice.

Results: Eighty-four completed questioners were returned anonymously. The majorities of the participants were female, and had practiced for ≤ 5 years. The survey showed that 76.2% of the participants had not received any continuing education or training courses on stem cells or regenerative dentistry. The majority of the participants (82.1%) believed that regenerative treatments should be included in dental practice. Of all, 76.2% had no umbilical cord or stem cell banking for themselves or a relative and 63.1% thought that dental pulp stem cell banking would be useful to regenerate dental tissues. Most of the participants (65.5%) had never performed regenerative therapy of any kind in their clinical practice and 51.2% of the participants were not sure whether regenerative procedures would be successful.

Conclusion: Although more evidence on the efficacy and safety of regenerative dentistry is required, postgraduate training in this regard seems necessary.

Objectives: Several software programs have been designed for outcome prediction of orthodontic and surgical treatments. This study aimed to review the accuracy and characteristics of cephalometric software programs for outcome prediction of orthognathic surgeries.

Methods: This study reviewed studies that compared cephalometric software programs in terms of accuracy and characteristics for outcome prediction of orthognathic surgeries. The results of studies regarding some two-dimensional (2D) and three-dimensional (3D) software programs for this purpose were collected and reported.

Conclusion: Use of diagnostic software programs for prediction of treatment outcome is an inseparable part of orthognathic treatment. Some studies have reported acceptable diagnostic accuracy of these software programs and their optimal efficacy for guiding the patients towards accepting or rejecting a treatment. However, using the manual technique to demonstrate the outcome of orthognathic treatment is still efficacious. Several factors such as updating the primary versions, their compatibility with the new operating systems, education and customer service are important in continuation of use of these software programs.

Objectives: Ectodermal dysplasia (ED) is a relatively common sex-linked dermatitis characterized by congenital dysplasia of one or more ectodermal structures and their accessory appendages. Common manifestations include fragile skin and nails, defective teeth and salivary glands, frontal bossing with prominent supra orbital ridges, nasal bridge depression and protuberant lips. Teeth are often few in number (hypodontia or oligodontia) and have a conical form that results in generalized spacing. In extreme cases, both deciduous and the permanent dentition may fail to form (anodontia) and consequently, hypoplasia of the jaws may happen. This article reports a case of ED with its management protocol.

Case report: A 4 year-old boy with hypohydrotic ED was referred to Dental School of shahid Beheshti University of Medical Sciences. Clinical examination revealed classical features of ED, with only a few teeth. He had fine scanty hair, dry skin and depressed nasal bridge. Removable denture was made with particular limitations for his lower jaw to restore esthetics and masticatory function. The existing upper teeth were initially reshaped using composite resin restoration material.

Conclusion: Preventive treatments in ED patients are very important to save the existing teeth. In patients with oligodontia, removable dentures can be used as a cost-benefit and pleasant intermediate treatment to restore function and esthetics and improve patient’s psychological status.