Journal of Dental Medicine

Levers in removable dental prostheses

Normal 0 false false false EN-US X-NONE AR-SA Teeth and periodontal ligaments can resist more efficiently opposing vertical forces parallel to their axial axis in comparison to horizontal forces. Thus, in designing dental prostheses and preserving interocclusal relationships we should notice to eliminate horizontal forces on teeth. A partial prosthesis can rotate in vertical, horizontal and Sagittal axis and by understanding levers and designing appropriate frameworks these rotations can be avoided.

Osteodistraction: Application in maxillofacial region

H. Mahmodhashemi

Normal 0 false false false EN-US X-NONE AR-SA Osteodistraction is a technique for increasing the length of bone in order to form new bone by using natural bone healing mechanism of the body. In general, Osteotomy surgery ( corticotomy) is done in the place which bone lengthening is needed. Then an external fixator is installed that is continuously lengthened and forms new bone at the same time. Distraction biology, Indications and contraindications in maxillofacial region and different methods of it is discussed in current article.

Evaluating the effect of a denture cleansing solution in chronic atrophic candidiasis patients using dental prosthesis

Normal 0 false false false EN-US X-NONE AR-SA Present study is conducted to evaluate antifungal activity of the denture cleansing solutions made in Iran. 40 patients who were diagnosed as chronic atrophic candidiasis after laboratory tests confirmation, were selected .Before and after using denture cleansing solution, their maxillary denture were sampled by a swab. The samples were cultivated and the resulting colonies were counted and the exact number of the colonies in 1cc of each suspension was determined. It was found that after using the solution, cultivation results were negative. Therefore, this solution has the potential to eradicate all the fungi causing chronic atrophic candidiasis.

A research on the relationship between anticipating the direction of mandible growth and symphysis morphology

Normal 0 false false false EN-US X-NONE AR-SA The study's purpose was to estimate the value of symphysis morphology as a standard for anticipating direction of mandibular growth. 160 patients were sampled (80 f/80 m) and formed 8 groups based on gender,age and growth spurt. Mandibular growth direction was evaluated via 6 cephalometric indices: Mandibular Arc angeles, Lower facial Height, Facial Axis , Facial Angle ,Facial Taper and Mandibular Plane. Height, depth and their ratio and angle of symphisis were measured. The highest relation found among 13-16 yrs females as well as +20yrs males. Symphysis angle showed the highest relation in male patients. In 9-12 yrs females and 10-14 male patients in which anticipating the growth is highly needed, the relationship between symphysis morphology and mandibular groth indices was not significant.

Assessment and research of the role of tongue in growth and related dentoskeletal disorders

A. Khavari

Normal 0 false false false EN-US X-NONE AR-SA In this clinical and paraclinical research carried out in 15 months, 83 individuals were selected among private office patients who were then decreased to 32 after consideration of some predesigned conditions of the study. 18 male patients of 6-11 yrs and 14 female patients of 5.5-9 yrs were participated in the study. Following scientific evaluations these results were obtained: abnormal size and function of the tongue can cause dentoskeleteal disorders and complications in other anatomical structures and physiological activities of the oral cavity even in absence of any other etiological factor. Neglecting this can lead to failure of orthodontic treatments and can be an important factor causing relapse. Besides, we cannot declare that the tongue volume is whether complementary to the forces or not. In conclusion, increased function because of increased tongue volume and growth can cause dental or dentoskeletal disorders.

Evaluating the effect of Die spacer on crown retention in fixed prosthesis

Normal 0 false false false EN-US X-NONE AR-SA Crown retention is related to its adaptation with tooth while there is always a gap between the crown and prepared tooth. Although this gap is filled with cements but the mechanical retention between axial walls and internal surfaces is decreased. Therefore, what is the relation between die spacer and crown retention? Does it affect retention? And if so, what is the best thickness of it? It has been a long time that various techniques are recommended and used to improve the adaptation of crowns. According to Fusayama and based on some other researches, it can be concluded that by using die spacer we can noticeably decrease the thickness of cement and improve the adaptation of cement. In addition, many studies on thickness and amount of die spacer concluded that by using die spacers, in %55 of cases crown retention was increased while in 30% decreased and 10-15% have not changed. Hence, it seems that using die spacer is generally beneficial and the best thickness of it according to our research is 2-4 layers that can improve retention by 41%.

A research on Canine movement by using sliding approach with or without hook

Normal 0 false false false EN-US X-NONE AR-SA Canine retraction was done for 19 patients. Movement , Tipping and rotation of canine and molar movements was done by two approaches of sliding hook and sliding mechanics using 16% wire and 18% twin edgewise brackets and were compared. 350 g force via elastic chin was applied and measurements were done both intra- and extraorally. There was not any significant statistical difference between canine and molar movements in both approaches. Canine Tipping and rotation in two approaches showed significant difference. In fact, both were lower in sliding hook approach than sliding mechanics. As lower tipping results were obtained in sliding hook approach, it is suggested to apply this method to bodily retract canine.

Evaluating the general process and researches on principal reasons of failure in adhesive restorations

A Azari

Normal 0 false false false EN-US X-NONE AR-SA Adhesive restorations have been introduced to dentistry for almost 3 decades and it could be stated that from that time there has been lots of ups and downs until emersion of current restorations. What was focused the most at the time of introducing these restorations was their long lasting estimated strength which has undergone many studies and now everyone is aware of their advantages and disadvantages. Although their real adhesion to teeth is still ambiguous and wide researches on biomechanics of oral cavity and the relation with adhesive restorations are in process. This article is aimed to present a novel method for preparation of metal surface. In first part, the process of research is explained and in two following parts the process of new method evolution and theoretic principles are mentioned. Finally, there is a 7 year report of clinical cases using new method.