Journal of Dental Medicine

In this study, 116 edentulous patients in the age group 37-90 yrs were selected. Out of the above,12 patients had visited the dept. Of prosthodontics for the first time for treatment. Other 34 of them were patients of the dental school and the rest were from Kahrizak and Nikan sanatoriums.Initially, the V.D. of rest was measured as usual for all the patients. After subjecting them to the excercises of completely opening and closing of the mouth for 15 no. of times, the rest position was measured again. Results show that the changes in V.D.R. after, excercises, relaxing the elevator and depressor muscles and the duration of usage of prosthesis, the following conclusions are obtained.
1. There is an increase in V.D.R. after tiring out the elevator and depressor muscles of the jaws.
2. There is a direct co - relation between the increased V.D.R. and duration of use of prosthesis after excercises.
3. Change in the V.D.R. after excercise is notably more in women.
4. No definite conclusion is obtained in the relationship between changes in V.D.R. after excercises and use of prosthesis during sleep.
5. As above no conclusions as yet can be deduced between changes in V.D.R. and different operators.

The purpose of this study was to determine the prevalence of dentofacial anomalies in 12 to 14 years old students in Tehran.The sample consisted of 500 students. 250 of them were females and 250 were males. The evaluation of saggital skeletal relationships revealed tha 16% of samples had normal occlusion, 48% of them had CI I malocclusion, 15,6% had CI II Div I malocclusion, 12% of them had CI HI malocclnsion, 5.2% of them had CI. II Div 2 malocclusion and 3.2% of them had pseudo CI III malocclusion. The prevalence of other dentofacial anomalies obtained in this study are, crowding 40.6%, deepbite 27.2%, spacing 20.6%, mandibular deviation 19.4%, unilateral posterior crossbite 9.2%, anterior openbite 6.6%, posterior openbite 5.6%, asymmetry 1.6% and bilateral posterior crossbite 1.6%. The prevalence of dental anomalies in the sample population was as follws: rotated teeth 13.4%, malposed teeth 12.2%, teeth with large size 3.2%, malshaped teeth 2.4% and teeth with smal size 2%. A part from determining the total values mentioned, the prevalence of saggital relationships oral dentofacial anomalies was assessed separately in each of the female and the male samples.

The purpose of this article is to study distribution of DMF(T) and its D,M and F protions exactllly. 1500 subjects were examined clinicaly. They were 5 to 70 years old, with average 24 years. Only cavitated and coronal dental caries included in this research.

 The results of this study are:
1. The caries lesions of upper and lower second permolars are equal.
2. Anterior to second premolars, the DMF(T) of upper jaw teeth is higher than lower jaw's one. Conversely posterior to second premolars, lower jaw teeth has higher DMF(T).
3. Deciduous teeth of females have lower DMF(T).
4. Permanent teeth of females have higher DMF(T).
5. The upper Canines of females are exceptions. Upper canines of females have lower DMF(T) than males' ones.
6. It seems that sex hormones influence DMF(T) through Saliva and eruption time of teeth.
7. Susceptibility to Caries relates to microbial plaque formation and salivary protection.
8. The females have more filled teeth than males.

The present clinical trial was designed to evaluate the regenerative potential of periodontal tissues in degree II furcation defects at mandibular molars of human using a slow-resorbing collagen membrane and a surgical treatment technique based on the principles of guided tissue regeneration.The patient sampleinclude 8 subjects who had periodontal lessions in right and left mandibular molars regions, including moderate to advance periodonal destruction within the radicular area. Following a baseline examination including recording the clinical measurements (PD, Al, HC, F.G.M) , the furcation- involved molars were randomly assigned in each patient to either a test or a control treatment procedure. Included the evevation of mucoperiosteal flaps, recording measurement from the cemento enamel junction (C.E.J) directly coronal to the furcation area to the alveolar crest and to the base of the defect-Horizontal furcation measurements were also made using a William's probe, finally a collagen membrrane placed on the involved area to cover the entrance of the furcation and adjucent root surfaces as well as a portion of the alveolar bone apical to the crest. The flaps were repositioned and secured with interdental sutures. A procedure identical to the one used at the test teeth was Performed at the control teeth region with the exception of the placement of the collagen membrance. Following surgery all patients were placed on a plaque control regimen. All Patients received normal postsurgical care and at 6 month post-surgery were scheduled for re-entry surgery. Before re-entry surgery all clinical parameters recorded again. The re-entry mucoperiosteal flaps were designed to expose the furcation area for measurements, as describedabove. There was clinical improvement in all measurements made in both the test and control patients (especially in test group) over the 6 month period. The horizontal and vertical furcation measurements did yield a statistically significant imporvement when companing the test patients to the control.

Since 1800, it is known that fungican invade human tissues and from 1900, there is a great deal of information about incidence and epidemiology and geographic distribution and fungal infections.Because of increased incidence of fungal infections on recent years and importance of these organisms in producing of systemic and muco- cutaneous diseases, many investigations are performed about these fungal.22patients was evaluated immunological)' and it was revealed that, 77% of patients had increased immunoglubin serum level that was denoted of a normal B. lymphocytes function. As a matter of fact, both immune system are involved in anti- candidia defence, humoral immunity inhibits the penetration of Candida into mucous membranes, skin and internal organs.

Eruption is a kind of development move of tooth from the place of its formation to its functional position in the mouth.Time and sequence of permanent's teeth eruption from the point of health diagnosis and orthodontic treatments is very important.Because of this, we decided to evaluate and determine the mean eruption time of canine and premolars from gum penetrations toward occlusion and also their sequence of eruption.The average time of eruptions in this study was higher than other similar studies.Our findings showed that the mean eruption time of canine and premolars in girls is earlier than boys lower canines erupt earlier than upper ones and maxillary premolars erupt before mandibular premolars in boys.

Growth factors are biological mediators that have a key roll in proliferation, chemotaxy and differentiation by acting on specific receptors on the surface of cells and regulating events in wound healing.They can be considered hormones that are not released in to the blood stream but have one a local action. Some of these factors can regulate premature change in GO to Gl phase in cell devesion cycle and even may stimulate synthesis of DNA in suitable cells, Growth substances, primarily secreted by fibroblasts, endothelia! cells, macrophages and platelet, include platelet derived growth factor (PDGF), insulin like growth factor (IGF) transforming growth factor (TGF)a and (3 and bone morphogenetic proteins BMPs that approximately are the most important of them. (BMP)s could be used to control events during periodontal, craniofacial and implant wound healing through favoring bone formation According toLynch, combination of PGDF and IGF1 would be effective in promoting growth of all the components of the periodontium.The aim of this study was to characterize growth factor and review the literature to determine the mechanism of their function, classification and application in implant and periodontal treatment.

:.In the result of first world investigations, it has recommended that most oral and dental disease (over 80%) can be prevented by oral hygiene Instruction and sanitary methods.In our investigation, we have wanted to estimate the rate of knowledge, attitude and practice of dentists in urmieh. Our results exhibited that the rate of dentist's knowledge about sanitary and preventive methods and their etiologic relations of oral disease is 95%.But in spite of this high rate of knowledge the dentists attitude rate is %55.48 and more strange is that the practice of these dentist in relation with sanitary and preventive methods for patients has evaluated about 66.17% that ,this rate is 13% more than their attitude rate. The cause of this strange result, may be is dentists un honestly answer or because of their high theoretical knowledge of our dentist. May be we thinking that this recent factor in spite of insufficient attitude has effected on their practice.

The purpose of this survey was the determine of effectiveness of preventive precisures. 320 twelve years school student have chosen randomly. After determination of DMFT All of them divided to 4 groups. First group as control and the other groups were as oral hygiene education 6-fluoride therapy and sealant therapy group in a period of two years.Results of this study showed that fluoride therapy was more effective than the other procisures than oral hygiene instructions.

After approximately 40 years of experience in the field of resin - bonded restorations (R.B.R),these restorations arc one of the most controversial. During these years, many suggestions have been made for better performance and increasing durability of these restorations. The aims of this paper are:1 - Reviewing the literature for the so many factors involving the success or failure of R.B.R.2 - Introducing a new and simplified method for increasing the durability and /or relention of R.B.R.

One of the major goals of periradicular surgery is to create a good apical sea! at the apex. This is done by sectioning of 2 to 3mm from the apex, preparation of a class I cavity and filling with a biocompatible material.The purpose of this in vitro study was to determine whether ultrasonic units used for root end preparations could change the surface & structure of resected root ends, as competed to common methods of retropreparation. Eighty-five extracted single rooted teeth were divided into five similar groups. Then instrumented and filled with lateral condensation method. Then three millimeter of apex was resected, retropreparaiions in two groups were done with low speed handpiece and round V) ^ur and cavities in two other groups prepared with the highest power of dentspiay ultrasonic unit with TFI-10 tip and in one other group prepared with the highest power of neo sonic ultrasonic unit with diamond coated CT-1 retro tip.Following root resection and retropreparation the surface of resected root ends were examined for the presence of any cracks or structural changes on the surface of resected root ends with stereo microscope 50x.The results of this study showed thai high power settings of ultrasonic units can increase the potential of crack formation on resected root surfaces. In conclusion it is better to use low power setting of ultrasonic for retropreparation.

Numerous techniques are used for treatment of tempromandibular disorder (TMD). Two aims should be considered when managing patients with TMD.a) pain reduction, feeling of improvement, prevention of untoward sequel of TMD.b) Complete cure and enabling the patients to continue a normal life as much as possible. For an exact and successful treatment the following certain rules should be followed:1} The physician's competence and knowledge in anatomy, physiology, psychology of the disorder.2) Pay attention to patient's statement and being sympathetic, developing rapport, performing a complete and careful clinical examination.3) Considering the patient's psychological or physiological deficits.4) Eliminating TMD Precipitating factor.In general, treatment of this disease like other disease of bones and muscles should not be addressed aggressively such as surgery or occlusion therapy. Simple and conservative methods should be applied for treating this disorder, as some cases are self-limiting and require no intervention.

Periodontitis affected root surfaces are hypermineralized and contaminated with cytotoxic and other biologically active substances.The instrumented surface will inervitably be coverd by a smear layer following root planing with or without flap.Smear layer is resistant to saline rinsing, but may be removed with agents such as acids (e.g.citric acid), tetracyclines, EDTA, and laser.Low pH aqueous solutions such as citric acid have been used in surgical periodontal therapy mainly for two reasons, It dissolves smear layer after a relatively short exposure time and it has been claimed to selectively remove root surface associated mineral exposing collagen to varying degrees. A root surface coated with collagen appears to be a preferred surface for fibroblast attachment, a cellular event fundamental to successful periodontal wound healing.Several studies indicate the potential of tetracycline (TTE-HCL) in periodontal regeneration. Its acidic pH suggest that it can be used as a demineralization agent and removing the smear layer and exposing collagen matrix of the dentin.Chalating agent (EDTA) working at neutral pH appears preferable with respect to preserving the integrity of exposed collagen fibers, early colonization, and wound healing. In addition, etching at neutral pH has been reported preserve adjacent tissue- vitality, while etching at low pH necrotizes the fiap and adjacent periodontium.Clinical and subclinical studies have demonstrated laser waves can remove calculus and bacterial plaque and pocket epithelium and strile the root surface and can expose the dentin collagen and dentinal tublules, and leads to pronounce reducing of probing depth around teeth diseased with periodontitis.

The aim of this retrospective statistical study was to determine the prevalcence and frequency of age and sex distributions of pemphigus disease. Pemphigus disease classified as autoimmune bullous dermatoses which is a chronic mucocutaneous disease.This study was performed in Razi Hospital and department of oral pathology of dental school, Tehran University of Medical Sciences. The most frequently effected area was buccal moucosa of oral cavity. The most rate of recurrence was found in oral cavity which being more common in middle age females (25-44 years).

: One of the main aspects of orthodontic treatments is hard and soft tissue changes and their effects on patients appearance.Fixed orthodontic treatment with extraction of upper first premolars to camulfalge of ci II malocclusion is very common,however there is not sufficient studies about lip and incisors changes after this procedure. For evaluating of vertical changes of upper, lip and incisors following retraction of upper incisors, fifteen adult Iranian patients aged 15 to 24 years who sought treatment for their CI II DI malocclusion were treated. Standard edgewise technique(0.018") following extraction of four first premolars were used.A cephaiometric study was undertaken to determine the vertical change in upper incisors and upper lip. For this evaluation, thirty linear and angular measurements were utilized.Results show that: 1- The upper incisors were intruded (X=0.83mm).2- The upper lip length was increased(X~1.2mm).3- The occlusal plane, rotated upward (Anteinclination).4- The palatal plane rotated downward and backward (Retroinclination).This study shows that the standard edgwise appliance has the capacity of reduction of incisor protrusion significantly without extruding them.

Peripheral giant cell granuloma (P.G.C.G) is an exophytic lesion with an approximate size of 0.5-1.5 mm. It usually occurs on gingival and alveolar ridge of mandible particularly in molar and premolar region. The relation of serum calcium (Ca), Phosphor (P), and alkaline phosphatase (Alk) levels to P.G.C.G is yet controversial. In this descriptive study, 33 patients with P.G.C.G were chosen and serum Ca, P, and Alk levels compared with the normal range. In all patients the level of Ca was in the normal range. Phosphor (P) was in the normal range in all patients over 17 years old and 80% under 17 years. The level of ALK in 75.8 percent of the patients over 17 years and 90% under 17 years was in the normal range. In conclusion, no relationship was found between serum changes and P.G.C.G. It means P.G.C.G can be compeletly independent lesions from serum changes.

A case involving the replantation of an avulsed incisor after long extra-oral period (8 days) is reported. After cleaning the root surface, the tooth was soaked in fluoride gel for 20 minutes and root canal therapy was performed extraorally. The tooth was stabilized by wire and composite for six weeks. The patient has been periodically recalled and the tooth monitored for 36 months after replantation. Only minor external surface resorption was observed in the periapical area on the rodiograph, which was taken immediately before removal of the splint and the rate of subsequent replacement resorption has been acceptable. It should be considered that and extended extraoral period is not an absolute contraindication to replantation. Teeth replanted after long extra- alveolar periods can function for a long period of time and thus postpone prosthetic treatment.

Dental enamel is the end product of amelogenesis, which can be considered to take place in three interrelated phases. When this complex sequence of cytological and physicochemica! events disrupted by genetic or environmental factors, the function of the ameloblasts may be disrupted permanently or temporarily. The result shows qualitative and quantitative defects that may range from a complete absence of enamel or a slight discoloration. The aim of this study was to determine the prevalence of enamel defects by DDE index in a randomly selection group of 1637 students age 7-12 years old in Isfahan (0.2-0.3 PPMF"). Enamel defects were present on one or more teeth in 27% of the cases. The most common affected tooth was the central maxillary and then first molar of maxilla. The most common affected surfaces were buccal. Hypoplastic defects were found in first molar however premolar and canine were affected by diffuse white lines opacity.

Postoperative pain following Root Canal Therapy (RCT) is the common problem for patients,dentist and dental staff. Regardless of cause it appears that postoperative pain and discomfort is related to periapical inflammation. The purpose of this study was to investigate histologically the effect of Ibuprofen on acute apical inflammation following RCT. on cat. Fifty-six cuspids teeth of 14 cats were divided into three groups, 6 cats for experimental group, 6 cats for positive control group and 2 cats for negative control group. In first group, to anesthesize the animals each cat received 10 mg/kg Ibuprofen 36 hours before RCT and repeated every 24 hours. In second group RCT was performed in 24 cat teeth without any prescription. In negative control groups 2 cats, no RCT were done.Following vital perfusion, in interval of 6, 12, 24 hours, samples were post fixed in 10% formalin and five micron sections were prepared, and stained with H&E and studied under the Mann Whitney parameter test. Infilteration of inflamatory cells in 6 hours interval in experimental group was significantly less than two control groups. In 12 hours samples, however, inflammation in experimental group reduced, but it was not significant. In 24 hours samples there was no significant difference between experimental groups and controls. The result of this in-vivo study shows prescription of Ibuprofen before root canal therapy can reduce inflammatory reaction.

Dentists and dental professional are constantly in contact with round, sharp, hot, and rotating instruments such as burs, scalpel blades, files, etc., in daily practice. Gate Glidden is one of the mentioned instruments used for removing gutta percha from root canal- treated teeth. In this article, a rare case of penetration of a fractured Gate Gildden bur into a dentist's elbow is reported and precaution instructions are discussed.