Abstract: The purpose of this study is to as certain whether the upper and lower third molars can contribute to the occurrence or aggravation of crowding. The sample of this study consisted of 187 subjects (103 males and 84 females) aged 20–30 years, then the sample was divided into two main groups and three subgroups. The groups consisted of crowded and normal subjects. The subgroups consisted of persons who had maxillary or mandibular third molars that were either impacted, erupted into function or agenesis.The results showed that the crowded group revealed a higher percentage of im-pacted third molar and a smaller percen-tage of erupted third molar particularly in the mandible and a smaller percentage of third molar agenesis than the normal group.The females had more impacted third molar in the upper and lower jaws for both crowded and normal groups. The percen-tage of third molar agenesis in the males was higher in the upper jaw and smaller in the lower jaw than the females.In normal group, no significant differ-ence was found between upper and lower jaws except in females where the uni-lateral third molar agenesis was greater in the lower jaw. In crowded group, the low-er jaw revealed a higher percentage of impacted third molar for all subjects and a smaller percentage of erupted third molar for females and a smaller third molar age-nesis for the males as compared with upper jaw.

Abstract: In this study the effect of mixing as received and as cast metals by different ratios on the marginal fitness of metal cop-ings casted by two types of base–metal alloys (Wiron 99 and Heraenium–NA) whi-ch are used by dental technicians in Iraq was evaluated. The general procedure consisted of first, fabrication of wax pattern on a standardized prepared brass die that represented an upper central incisor with a heavy chamfer cervical margin. The wax patterns were standardized by the aid of a split mold constructed spec-ially for this purpose; the total number of wax patterns was 100. Each fifty copings were casted with one of these two alloy types, and each type was divided into five sub–groups according to the amount of as received (new) and as cast (recasted) metals mixed. Completed castings were finished and seated on the die. The marginal fitness of each copying was determined by measur-ing the vertical discrepancies between the gingival margin of the copying and the margin of the preparation at four reference points on the labial, mesial, palatal, and distal aspects of the die with the aid of light traveling microscope. The statistical analysis of the results re-lated to Wiron 99 alloy group showed that there were highly significant differences bet-ween its related five sub–groups indicating that the marginal fit changes increased with the increase of the recasted metal ratios ofNA alloy did not show significant differen-ces among its sub–groups indicating that re-casting it, in different ratios reaching up to 100% as cast alloy, did not cause adverse changes on marginal fitness.Based on this, conclusions drawn indi-cated that recasting of Heraenium–NA (Ni–Cr) can be utilized as a good substitute for the new alloy from an economical point of view. 

Abstract: The radiograghical interpretations can give an excellent indication about the biological response of hard tissue like bone to different foreign materials imp-lanted within it. This clinical study was carried out to evaluate radiographically the bone reac-tion of four different types of Iraqi manu-factured amalgam alloys (in addition to Degussa alloys as a positive control) implanted within holes prepared in the mandibular bone of the rabbit, and addi-tional negative control group in which the hole remained empty without any implan-ted materials was also included. The evaluation was done by careful verification of the presence or absence of the radiolucency at the periphery of the implanted amalgam at three different time intervals, the response varied from radio-lucency to radioopacity depending on the reaction of bone to different implanted amalgam alloys. Accordingly, the biocom-patibility of the amalgam alloy was deter-mined depending on the radiographic pic-ture of bone response at the margin of the implanted alloys. The results showed no significant difference in bone response among the different types of alloy used.

Abstract: This study was carried out to evaluate the colour property of two types of acrylic resin materials cured by microwave tech-nique in comparison with that cured by conventional water bath technique. Two types of heat cured acrylic resin materials were selected: Quayle–Dental and Major–base types. Seventy–two sam-ples (30×20×1.5 mm) were prepared and divided into four experimental groups: Quayle–Dental and Major–base groups were cured by microwave technique and the others Quayle–Dental and Major–base groups were cured by water–bath techni-que. The number of samples for each gr-oup was 18. The colour property for the samples was evaluated using computerized ultra-violet–visible spectrophotometer with acc-uracy up to 0.001 nm. The absorbed light was measured which is also termed the optical density. The results of this study showed that there were no significant differences in optical density for acrylic resin samples cured by microwave and water–bath tech-niques, and the acrylic resin with smaller particle size (Quayle–Dental) showed hi-gher optical density (colour property) than that of larger particle size (Major–base).

Abstract: In this study, alkalinizetion of com-mercial local anesthetic solution was attempted in order to determine its effect on onset and pain experienced during injection as well as its effect on depth of anesthesia achieved for maxillary tooth extraction. Total 200 patients participated and randomly distributed into two groups, 100 patients for each. The first group received maxillary infiltration anesthesia for extraction of maxillary tooth with commercial local anesthetic solution at pH 3.5, and the second group received the same injection with alkalinized solution to pH 7.2 using sodium bicarbonate 8.4%. The result of this study showed a significant rapid onset in pH adjusted group comparing to control group. Signifi-cant difference noticed between both gr-oups regarding pain noticed during injec-tion with less pain experienced in study group. No significant difference in the depth of anesthesia achieved. When data assessed for patients with periapical lesion only, a significant difference noticed bet-ween pH adjusted group comparing to control group and less pain recorded during extraction with enhanced depth of anesthesia achieved in study group. In conclusion, pH adjusted anesthesia, although not recommended routinely, co-uld be used to reduce injection pain when severe pain on injection expected. Also, it could be used for patient with periapical lesion to enhance depth of anesthesia.

Abstract: Many dental materials have been marketed locally in the last few years. The dentist should understand the selection pri-nciples that based on scientific tests to choose the product. Dental amalgam alloy is one of the dental materials that used in restorative dentistry for restoration decayed teeth. The primary objective of the study is to examine the lathe–cut Iraqi dental amalgam alloy (Al–Rafidain) microscopi-cally. The examination of alloy powder particles shape was made with transmitted light microscope using “Taha Indicator” instead of reflected light microscope or electron microscope. The results showed that the examina-tion with transmitted light microscope by using “Taha Indicator” give obvious and clear image of the alloy powder particles and also showed that Al–Rafidain amal-gam alloy powder has large and irregular shape particles that may give inferior physical properties to the product, so more evaluation and examination by other rela-ted tests may be needed.

Abstract: The present study was conducted to investigate the safety and efficacy of oral contraceptive drugs on oral health and to determine the prevalence of dental caries, plaque, calculus and gingival indices. The sample comprised of 90 females attended to Family Regulation Unit of Al–Hadbaa Health Center in Mosul during the period from 2003 to 2004. Sixty females using oral contraceptives (for at least three years), which are combinations of oestro-gen and progesterone. The other 30 heal-thy women were acted as control group with similar age groups and a mean age of 31 years. The oral contraceptive drugs modify oral health. In the present study, the prev-alence of dental caries, plaque, calculus and gingival indices increased in all wo-men using oral contraceptive drugs than the prevalence in the women of the control group. In view of the possible factors that cause increase of the indices, suggested a hormonal factor especially oestrogen and progesterone hormones, which have an effect on rate and pattern of hard and soft tissues resulting in reduced the ability to repair and maintain the oral health status.

Abstract: The aim of the study is to evaluate the oral hygiene and gingival health and to find if there is any variation between sex and age groups among adults aged 21–80 years in Thamar–Yemen. A sample of 224 individuals aged 21–80 years (177 males and 47 females) were examined using plaque index by Silness and Löe (1964) and gingival index by Löe and Silness (1963). The results showed that the mean plaque score for the total sample was 1.15; the plaque index was increasing with age significantly. Males reported higher means than females with statistical significant difference in the 3rd, and 5th age groups; while at the 4th age group the females rep-orted significantly higher plaque scores than males. The mean gingival score for the total sample was low (0.84) and it was increa-sing with age significantly. The mean gin-gival score was slightly better in males than females with statistical significant difference in all age groups except the 5th age group where the females showed bet-ter gingival health. Therefore, the objective of dental health education to those adults is to imp-rove the effectiveness of oral hygiene pra-ctice by tooth brushing and interdental aids.

Abstract: This study was undertaken to design the relationship between different ortho-dontic cases and amount of bone level loss. The study sample consisted of 72 male students (20–23 years old) classified into 3 groups: Control group with normal overjet and overbite, overjet group with at least 8 mm, and overbite group with at least 6 mm. The results showed a sign-ificant reduction of bone height in upper and lower incisors in malocclusion group at significant level 0.01 if it is compared with normal group bone level.

Abstract: This clinical investigation was under-taken to compare the antibacterial activity of two mouth rinses (chlorhexidine diglu-conate 0.2% and phenolic compounds) with salty water (0.9% NaCl) to assess their ability to control plaque and gingival inflammation in conjunction with a normal daily home care in patients with fixed orthodontic appliance. In this clinical trial, 45 patients were randomly divided into three groups; each containing 15 per-sons matched in age and gender, they were instructed to use rinses twice daily for 30 seconds after breakfast and before the bed-time. The gingival and plaque indices were measured according to Silness and Löe for the six teeth at the baseline and two mon-ths after rinses. The results of the study revealed that there is a significant reduction at p < 0.05 after rinsing with phenol and chlorhexi-dine digluconate for gingival index, while non significant change for salty mouth-wash, and only significant reduction in plaque index for chlorhexidine digluconate mouth rinse and non significant one for phenol and salty mouthwashes. These re-sults support previous published results on the superiority of 0.2% chlorhexidine di-gluconate when used in conjunction with professional care as an adjunct to routine oral hygiene practice in orthodontic pati-ents.

Abstract: The adherence of Candida albicans on acrylic resin denture base surface is co-nsidered as the first step in the pathogeni-city of candida–associated denture stoma-titis which is the most prevalent form of oral candidiasis in denture wearers. This study was an in vitro study aimed to eval-uate the anifungal effect of fluconazole, nystatin and chlorhexidine and their anti-adherent effect on Candida albicans cells that attached on the fitting surface of den-ture base. It was determined, using broth microdilution method at two concentra-tions for each drug, and the results were determined using spectrophotometer. All drugs had a highly significant antifungal effect on Candida albicans isolate at their two concentrations. The effect of saliva on the adherence of Candida albicans on the fitting surface of denture base was also considered. This study concluded the importance of saliva in increasing the microbial adherence; i.e., the mean number of adherent cells on ac-rylic resin samples in the absence of saliva was 7.4 + 1.9 cell/mm2 and with the pre-sence of saliva the number was 29.1 + 2.7 cells/mm2. The number of remaining adh-erent cells was counted using fluortescent microscope. The mean number of remain-ing cells which adhered on acrylic resin samples after the immersion in first con-centration fluconazole, nystatin and chlorhexidine for one hour respectively were 4, 5 and 2.6 cells/mm2 and for the second concentration/1 hour the numbers were 3.2, 4.1 and 1.7 cells/mm2 compared to the normal number of adherent cell 29.1 + 2.7 at p<0.01.

Abstract: The purpose of this study was to det-ermine the more accurate method for pre-dicting the width of unerupted mandibular premolar of mixed dentition patients, whe-ther by the multiple regression analysis method or by radiographic measurements of deciduous molars width method. Multiple regression analysis method was performed on data derived from 108 children (62 females and 46 males) aged 9–12 years old. These children were selec-ted from primary schools located in differ-ent areas of Mosul City. All subjects had normal Class I molar relationship with mixed dentition (the right and left perman-ent centrals, laterals and first molars, and right and left primary canines and first and second molars). The data were statistically analysed using Statistical Package for Soc-ial Statistics. The results revealed that there were no significant differences in mesio–distal crown diameter between right and left sides of both unerupted premolars and deciduous molars. All the teeth in males were larger in mesio–distal crown dia-meter than females. Also, the results of the present study indicated that there was a positive correlation between most of the teeth, individual teeth and groups of teeth. There was a difference in the means bet-ween the mesio–distal crown diameter of deciduous molars and unerupted premo-lars. The present results used to generate a formula “linear regression equation” that can be used clinically to affect prediction depending on the mesio–distal width of individual deciduous molars.