Journal of Dentistry, Shiraz University of Medical Sciences
Volume:15 Issue: 3, Sep 2014

Keratoacanthoma (KA) is a comparatively common low-grade tumor that initiates in the pilo-sebaceous glands and pathologically mimics squamous cell carcinoma (SCC). Essentially, strong debates confirm classifying keratoacanthoma as a variant of invasive SCC. The clinical behavior of KA is hardly predictable and the differential diagnosis of keratoacanthoma and other conditions with keratoacanthoma-like pseudocarcinomatous epithelial hyperplasia is challenging, both clinically and histopathologically. This article aims to illustrate and explicate some of these complicated issues by presenting two cases of KA and a relevant review of literature. It also targets the clinical, histopathologic, and immuno-histochemical features of these two cases.Both presented lesions of this study had appeared on the vermilion border of the lower lip and no vascular or perineural invasion was observed. The results of the immuno-histochemical survey, particularly in staining with marker CD30, confirmed the differential diagnosis of keratoacanthoma from keratoacanthoma-like pseudocarcinomatous proliferations which was consequent to the CD30+ lymphoid infiltration.Histopathological and immunohistochemical investigation is necessary to disprove the invasive biologic behavior of keratoacanthoma and also to refute all conditions with keratoacanthoma-like pseudocarcinomatous epithelial hyperplasia.

Statement of the Problem: Impression materials are concerned as a significant source of cross-contamination because of exposure to blood and saliva. Considering the importance of infection control in the dental environments, this study is performed to investigate the dimensional changes of two condensation silicone impression materials, Speedex and Irasil, after immersion in 0.5% sodium hypochlorite. In this in-vitro study, two condensation silicone impression materials, Speedex and Irasil, were used on a prefabricated metal model having two dies, one with and the other without undercut. Each impression material was used to prepare 30 impressions; half of each group was immersed in 0.5% sodium hypochlorite for 20 min. The casts were prepared and a profile projector was used to measure the casts in terms of height and diameter of the die without undercut, distance between the two dies, die diameter below the undercut, and the height of the die above the undercut. The results were statistically analyzed using Student t-test. In Speedex group, an increase was detected in the height of die without undercut and the height of the die above the undercut, but other dimensions have decreased. No significant change was observed in dimensions of Speedex group except for the distance between the two dies and die height above the undercut. In Irasil group, the height of the die without undercut, the distance between the two dies and the height of the die above the undercut have increased; while decrease was observed in other dimensions. Compared with the original sample, no significant difference was observed in dimensions except for the height of the die above the undercut. These changes for Speedex group include changes in distance between the two dies and the height above the undercut which can impede proper placement of prosthesis, particularly fixed partial dentures in which the accuracy of the distance between the two dies are of utmost importance. In Irasil group, the height of above the undercut was altered and this negative effect is highlighted in registering the reduced single tooth with an undercut.

Statement of the Problem: Fixed retainers were developed to maintain incisor alignments after orthodontic treatments. Although the effects of fixed retainers on periodontal health are clinically studied, no studies have still evaluated the histological changes in the periodontium after the placement of thefixed retainers. The aim of this study was to evaluate the effects of customised retainers on periodontium histologically. Forty pairs of maxillary and mandibular central incisors of twenty rabbits were randomly divided into four equal groups: The first group was considered as the control and in the second group, Fiber Reinforced Composite (FRC), in the third group, 0.014 inch stainless steel (SS) wire and in the fourth group, 0.175 inch multistrand stainless steel (MSS) wire were bonded on the labial surfaces of the incisors. After sixty days; animals'' periodontium were evaluated histologically. The number of bone resorption lacuna in the control group was significantly less than FRC and 0.014 SS groups. The periodontal vessel count and their diameter in the control group was significantly lower than the other groups. The pulp vessel count and their diameter in controls were significantly more than the 0.014 SS and the 0.175 MSS groups. Findings of this study suggest that FRC fixed retainer might cause detrimental effects on the periodontal ligaments and supporting bone and the 0.014- inch and 0.175- inch fixed retainers can cause hyalinization and possibly the necrosis of the pulp.

Statement of the Problem: Alveolar bone necrosis induced by Herpes zoster infection is considered as a rare manifestation of osteomyelitis and few case reports are presented in the literature. The aim of this study was to evaluate mandibular osteomyelitis caused by herpes zoster in the immunocompromised patients with histopathologically documented osteomyelitis in the mandible and herpes zoster infection. 30 patients were recruited in this cross-sectional study. 19 patients were completely edentulous, 4 patients were partially edentulous and 7 with complete dentition. In all cases, specimens were analyzed using a conventional polymerase chain reaction (PCR) test for varicella zoster virus. 16 patients underwent dialysis, 9 patients received chemotherapy treatments and 5 patients had transplantation (four kidneys and one liver). Histopathological assessment demonstrated a nonspecific bone necrosis exhibiting an eosinophilic, homogeneous non-vital bone tissue with peripheral resorption surrounded by reactive connective tissue. PCR test was positive in 21 cases. This study demonstrated that the frequency of osteomyelitis induced by herpes zoster could be more than the records provided by previous studies. Histopathological findings might be nonspecific in such patients. PCR test was not positive for all HZ induced osteomyelitis patients.

Statement of the Problem: Optical properties of the composite resins, concerning their translucency and thickness, are affected by discolored tooth structure or inherent darkness of the oral cavity. This study aimed to compare the translucency parameter (TP) of five different composite resins in different thicknesses and to evaluate their masking ability in black backgrounds. Five brands of composite resins; Gradia (GC) and Crystalline (Confi-dental) in opaque A2 (OA2), Vit-l-escence (Ultradent) in opaque snow (OS), Herculite XRV (Kerr) and Opallis (FGM) in dentin A2 (DA2) shades were selected to enroll the study. Color coordinates of each composite were determined at 0.5, 1, and 1.5 mm thicknesses on a white backing. The backing of material itself and a black backing were calculated by using a spectrophotometer to evaluate the translucency parameter (TP) of the study materials. The masking ability was also calculated from the specimens on the material itself and on black backing. The values under 2 were estimated as imperceptible. One-way ANOVA, T-test and Tukey HSD were employed for statistical analysis. The masking ability values, recorded for the 1.5 mm-thick specimens, were in the range of imperceptible except for the Herculite. There was no difference in TP values of the materials at 1.5 mm thickness. Opaque snow shade of Vit-l-escence and opaque A2 shade of Gradia showed lower TP values in comparison with the other 1 and 0.5 mm-thick materials and this difference was statistically significant (p< 0.05). In relatively thin thicknesses (≤1mm), these opaque/dentin shade composite resins could not mask the black background color.

Statement of the Problem: Premedication is expedient in reducing the psychological trauma from recalling the unpleasant pre-anesthetic phases, hence, inducing a trouble-free anesthesia. This study aimed to determine the effectiveness of oral midazolam in co-operation of the subjects before general anesthesia and in recalling the pre-anesthetic phases, performed on children candidate for dental treatment under general anesthesia. In this prospective clinical trial study, 62 healthy non-cooperative children, candidate for dental treatment under general anesthesia, were randomly divided into study and control groups. The children received 20ml orange juice, 20 minutes before starting the anesthesia. The juice of the test group contained 0.5mg/kg of midazolam and that of the control group included no medication. The induction and the maintenance process of anesthesia were similar in both groups. The manner of subjects when separated from parents, their cooperation during intravenous catheterization, and recalling the pre-anesthetic events were recorded. Data were analyzed by adopting chi-square and Mann-Whitney tests. Most of the children in the test group had a comfortable separation from parents, restful IV catheterization and 90% of the subjects did not recall the pre-anesthetic events. Under the circumstances of this study, it could be concluded that 0.5mg/kg oral midazolam premedication is effective for comfortable separation of children from parents and restful IV catheterization and also forgetting the pre-anesthetic events.

Statement of the Problem: No published literature was found studying the people''s reasons on why to choose or not to choose a dental care setting in south Iran, while understanding their attitude towards choosing their dental care center is consequential for planning a successful oral health care service system. To determine the factors affecting how people of the city of Shiraz choose their dental health services. A cross-sectional analytic study was designed. A self-administered questionnaire was produced, tested and then distributed among 570 multistage randomly selected parents of schoolchildren of the city of Shiraz. Independent t-test, paired t-test and Spearman correlation were used to analyze the factors influencing participants in choosing clinics for their esthetic and non-esthetic dental treatments. 400 questionnaires were complete and analyzed. The recommendation from others was found to be the most encouraging factor to choose a dentist or a dental clinic. More importance was reported for various factors affecting participants'' choice of dental clinic when seeking non-esthetic treatments, while recommendation and reputation of dentist/dental clinic played a vital role in esthetic treatments. The cost was more important for respondents living in more deprived districts (p= 0.05), for unemployed group (p< 0.001) and for those with less education (p< 0.001). Factors affecting people''s choice for dental care proved to be highly complicated. Recommendation was found playing an important role. Dental patients consider various factors when looking for non-esthetic treatment but would go for the best possible when seeking esthetic treatments. Findings of this study indicate that patients’ choice and utilization of dental service can be improved if dental clinics provide high quality of dental care with reasonable fees.

Statement of the Problem: Reducing the patients'' stress can prevent, or at least, limit the increase in blood glucose level. The study compares the effect of propofol and midazolam on blood glucose level in the patients undergoing dental implant surgery. The effect of pre-operational stress on blood glucose level during the surgery is also evaluated. This prospective randomized clinical trial recruited 33 patients undergoing dental implant surgery and divided into two groups. Conscious sedation was performed by midazolam in one group and with propofol in another group. The pre-operational stress was scored and the blood glucose level was measured in 4 different stages; before the operation, two minutes after the local anesthetic injection; thirty minutes after the onset of operation and at the end of the operation. The results were analyzed by employing ANOVA and Pearson test. The p Value was adopted 0.05 and the confidence coefficient was assumed 95%. The average levels of the blood glucose in midazolam and propofol group were 93.82 mg/dl and 94 mg/dl before the operation which displayed a meaningful increase of blood glucose level in both groups as the operation went on. The values were 103.76 mg/dl for midazolam and 108.56 mg/dl for the propofol group (p< 0.05) at the end of the operation.No statistically significant difference was found in the average blood glucose level between two groups in the different stages of the operation (p= 0.466). The Pearson correlation coefficient test revealed a higher increase in the blood glucose level in the patients with a higher pre-operational stress score (r= 0.756, p< 0.001). Based on the results yielded by this study, patients who receive venous sedation, either by midazolam or propofol, experience increase in the blood glucose level while undergoing an operation. No statistically significant difference was detected between midazolam and propofol.

Statement of the Problem: Trigeminal neuralgia (TN) presents with a shooting pain in maxillofacial region which compels the involved patients to visit many medical and dental physicians to relieve the pain. Hence, assessing the outcomes of different treatment modalities may help the patients and their clinicians choose a suitable practical method of treatment. The study was aimed to evaluate the outcomes of different treatments of TN and to determine which surgical or non-surgical treatment is better for controlling the pain. This study included 42 patients with trigeminal neuralgia. A questionnaire was completed for each patient in order to evaluate the pain control status of patients’ treatment with non-surgical (pharmaceutical) and surgical modalities. The questionnaire consisted of questions on an datasheet, concerning the duration of involvement with the condition, type and dose of the medication(s) used, the surgical technique administrated, patient satisfaction with the treatment modality and the intensity and frequency of the pain if present. The purpose of the study and the necessary information regarding the questions of the data sheet was given in detail to the patients for a careful completion of the questionnaires. Data was analyzed by adopting t-test using SPSS software. The results showed that the patients treated with pharmaceutical modalities had relatively lower improvement rate than those treated with surgery combined with medication (p< 0.035). Carbamazepine was the most consumed medication for pain control and the microvascular decompression was the most performed surgical method in patients. Although medication therapy alone was less effective than surgery combined with medication, both treatment modalities were significantly effective in controlling the pain of patients.

Epidermolysis bullosa (EB) is a group of rare inherited skin and mucous membrane disorders in which blister formation may arise spontaneously or following a minor friction. Various patterns of inheritance are explicated for the disease. The disease has a profound effect on oral mucosa and may result in high prevalence of dental caries. General anesthesia is sometimes the only choice for dental treatments in patients with EB. The following case report describes the dental and anesthetic management of an 12.5 -year-old girl with dystrophic type of EB. The patient was followed up every 6 months. New carious lesions were detected one year after the treatment, on the last visit. Presenting a perfect dental care to children with this disorder can be challenging for the in charge specialist, both pediatric dentist and anesthesiologist.