Abstract: Aims: To investigate the contribution of both tooth size and dental arch dimensions to dental crowding and spacing. Materials and Methods: ninty one pairs of dental casts of subjects aged 15–25 years with Cl I molar occlusion were selected for this study. The sample was divided into 3 groups: the spaced (29 pairs), the normal (32 pairs), and the crowded (30 pairs) groups. For each pair of dental casts the follow-ing parameters were measured: individual and combined mesiodistal tooth dimensions, intercanine and intermolar widths, arch perimeter, and arch length. One way analysis of variance and Pearson correlation coefficient were used for the statistical analysis. Results: significant difference was noticed among the three groups for tooth dimension both individually and combined. The spaced group showed the smallest tooth size, while the crowded group was found to have the largest tooth size among the three groups. The crowded group showed a significantly smaller upper and lower arch widths and arch perimeter when compared with the spaced and normal groups. The spaced group showed larger upper and lower intercanine widths and upper arch perimeter when compared with the normal group, but this difference was significant only for upper intercanine width. Correlation analysis revealed that spaced group has significant correlation between the space discrepancy and the sums of 6 anterior and 12 teeth in the low-er arch. While, space discrepancy in the crowded group showed significant correlation with the sum of 12 upper teeth and upper intercanine width and with lower intercanine width and arch perimeter. Con-clusions: variations in mesiodistal tooth size and dental arch dimensions do exist among crowded, spaced, and normal dental arches. These variations should be taken into consideration when choosing orthodontic treatment techniques used for resolving problems related to space discrepancy.

Abstract: Aims: The aim of this study is to detect the interrelation between the cranial base and the facial heights involving age and sex differences. Materials and Methods: The study was carried out on cephalo-metric of 63 subjects divided into two age groups: The first group including 36 subjects of 10–15 years and the second group including 27 subjects of 16–25 years, both groups of normal Cl.I molar occlusion with full set of permanent teeth. Lateral cephalometric radiograph were selected from computer of digi-tal radiography system (Planmeca dimaxis version 3). Nine linear measurements three for cranial base and six for facial heights with one ratio posterior to anterior facial height were evaluated. Results: There were a significant increase in means of group 2 for each cranial base and facial heights meas-urements, also within each age group means for male samples showed a significant increase in compar-ison with those of females. Posterior to anterior facial heights ratios were involved in normal range for both age groups. In addition a significant positive correlation were found between most of cranial base measurements with those of facial heights. Conclusions: Positive interrelation may be existed between growth of cranial base and growth of facial heights structures.

Abstract: Aims: This study designed to determine the force degradation of elastomeric chains (Dentaurum) at different time intervals in different media (air, distill water, Biofresh mouth wash and artificial saliva) and to compare the effect of wet and dry conditions on the force relaxation. Materials and methods: forty new modules of elastomeric chain of sex loops length divided into 4 main groups according to the environment (air, distill water, Biofresh mouth wash "F" and artificial saliva pH 6.75)and stored in an incubator at 37°C, Mean load were recorded for the samples at each time interval zero,1, 24 hour and 1 and 3 weeks respectively, the load measurement were done by tensile testing machine with use of spe-cial fixture to hold the samples and stretched over special framework. Results: The results showed that the mean percent force remaining of elastics is affected by stretching, water absorption, chemicals and times and the amount of loss in dry is less than in wet environments and especially in biofresh mouth wash more than the neutral saliva. Conclusions: the elastomeric chains are greatly affected by stretch-ing, moisture and time.

Abstract: Aim: The aim of this study was to evaluate the clinical performance of tooth, or teeth supported over-dentures with Rhein'83 attachment vis a vis conventional dentures. Materials and Methods: four pa-tients aged (45 to 65) years, comprising of 2 males and 2 females, selected from the Prosthetic Depart-ment, College of Dentistry, University of Mosul. The prosthesis provided included 3 complete upper overdenture, two complete lower overdenture, three of them with Rhein'83 attachment and two with out attachment. Results: Patients response were uniformly pleased with the service that they had re-ceived. They felt that they could chew well and preferred having over dentures with attachment. Con-clusions: Overdentures with Rhein'83 attachment are more stable and functionally more retentive in comparison to conventional denture therapy. But this mode of treatment takes longer time to fabricate. Patient satisfaction and acceptance of the overdenture treatment modality is superior when compare to conventional dentures.

Abstract: Aim: The purpose of this study was to determine the mucosal thickness changes in two types of remov-able partial denture base materials (Cobalt Chrome and Flexible) wearers over a two months period. Materials and Methods: Six patients (three men and three women) were included in this study, old ages group was over 50 years. The partially edentulous patients were randomly chosen from the De-partment of Prosthodontics, College of dentistry, University of Mosul. The effect of wearing flexible and conventional cobalt chrome (Co-Cr) RPDs on the underlying mucosa were studied, special record base of visible light cured made for each patients with three holes were used to record clinical meas-urements using digital caliber and followed up for two months after insertion of denture. Results: The result of this study indicated that there are significant mucosal thickness changes in the central and lin-gual (palatal) positions of the Co-Cr RPDs groups; with no significant mucosal thickness changes in three holes of the Flexible RPDs groups. Conclusion: This study concluded that the flexible denture is a good optional treatment in removable prosthodontics management. Patient satisfactions with flexible removable partial denture during function were concluded according to patients remarks in relation to cobalt chrome (Co-Cr) removable prosthodontics type.

Abstract: Aims: To determine and compare the palatal dimensions of Iraqi adolescents with different Angle clas-sifications in Mosul City, and to determine the correlation among the palatal dimensions. Materials and Methods: the sample consist of 142 orthodontic models of school students aged 13 – 17 years with different occlusal relationships (class I normal occlusion, class II (division 1 and 2) and class III malocclusions). Eleven palatal parameters were measured by using dental vernier and included; den-tal arch width at the canine, 1st premolar, 2nd premolar, 1st molar , arch depth at canine and 1st molar, palatal height at canine,1st premolar, 2nd premolar, 1st molar and arch perimeter. The mean and stand-ard deviation were calculated , analysis of variance(ANOVA), Duncan's multiple analysis range test and Pearson's correlation coefficient were used for the statistical analysis. Results: Class I normal oc-clusion had wider inter 1st premolar width and shallower palate at the canine ,premolars and molar region as compared with malocclusion groups in both genders, while Class II division 1had narrower and higher palate than other occlusal groups. Class II division 2 had shorter canine and molar depth than other occlusal groups in both genders in addition Class II division 2 had smaller arch perimeter as compared to other occlusal groups in females. The correlation among palatal dimensions revealed that palatal widths, arch perimeter and molar depth were highly and positively correlated with each other, while palatal height measurements were only positively correlated to each other and negatively poorly correlated to other measurements in all occlusal groups except in Cl II division 1 in males .This shows a highly significant correlation of palatal height at 2nd premolar and 1st molar with inter premolars and 1st molar width. Conclusions: Differences exist in most of palatal dimensions among different types of malocclusion and Class I normal occlusion these differences may help to define the dental character-istics of these problems and simplify their therapeutic managements and palatal expansion may be con-sidered before or during treatment class II division 1.

Abstract: Aims: To evaluate the effect of In-Office enamel vital bleaching with (35% H2O2) and the effect of immersion in artificial saliva following bleaching on the shear bond strength of titanium orthodontic brackets bonded with an orthodontic composite adhesive. Materials and Methods: The samples of the study were categorized into three main groups; bleaching, immersion and control group. Each group was consisted of 10 teeth (Human upper right first premolars). Specimens in bleaching group were bonded immediately after bleaching; immersion group specimens were bleached, then immersed in artificial saliva and held for 1 month before bonding. All specimens were bonded with titanium ortho-dontic brackets (ROTH, slot size 0.018 inch). The shear bond strength was measured by using the un-confined shear testing machine. Results: Bleaching group had the lowest shear bond strength whereas the control group had the highest one. No significant differences were noted between the immersion and control group (at p ≤ 0.05). Conclusions: In-Office enamel bleaching was significantly reduced the shear bond strength of orthodontic brackets. Immersion in artificial saliva (following bleaching) was able to improve the reduced shear bond strength.

Abstract: Aim : The paper aims to evaluate the effect of teeth wear severity associated with bruxism on the con-dylar height asymmetry index among different gender using panoramic radiograph viewing technique. Materials and methods: One hundred fifty subjects were participate in this study. Seventy five were bruxers and seventy five were non-bruxers. Degree of tooth wear severity was graded using Smith and Knight method. The panoramic radiographs were taken for each patient using a panoramic apparatus to determine vertical mandibular height asymmetry indices by a method developed by Habets et al. Mann-Whitney U test, Kruskal-Wallis test and Pearson Chi-Square test were used to determine the possible statistically significant differences between groups set at (P ≤ 0.05).Results: The results showed there are significant differences between the vertical mandibular height asymmetry indices of the bruxers and non-bruxers subjects. The female bruxer subjects had the higher condylar index value than that of the male but statistically , there is no significant difference, while the severity of tooth wear had a signifi-cant different affect on the condylar indices. Conclusions: The results showed that the vertical man-dibular asymmetry indices were affected by the tooth wear associated with bruxer subjects. The bruxer subjects had the higher value than the non-buxer subjects and there is no significant difference of the condylar index of bruxer subjects among different genders. While , condylar index value increased significantly as the tooth wear severity grade increased.

Abstract: Aims of the study: To assess the effect of age, sex, Angle classification, extraction of the teeth and severity of malocclusion on orthodontic treatment duration using Peer Assessment Rating (PAR) index. Materials and Methods: Upper and lower study models of 100 patients (50 males and 50 females) before and after orthodontic treatment with age ranged between 15-25 years old of different types of malocclusion were selected from four private orthodontic clinics in Mosul City according a certain criteria. The data were collected for each patient from their case sheet includes age, gender, PAR index before and after treatment, treatment time in months, extraction cases and the Angle classification of malocclusion. The PAR index was measured according to criteria of Richmond et al, and then Pearson Correlation Coefficient was used among these variables. Results: The percentage of reduction in PAR index was highest in Class I malocclusion (97.2%) followed by Class II (92.2%) and Class III (90%). No significant correlation was observed between the percentage of reduction of PAR index and time of treatment, also no significant correlation was found between patient age and treatment time at this age group (15-25 years), but there was a significant correlation between PAR index before treatment and the treatment time in Class I non extraction, Class II and Class III malocclusion extraction cases. The mean treatment time was 14.44 months for Class I, 16.92 months for Class II, 21.25 months for Class III malocclusion. Conclusions: both treatment duration and cost effectiveness could be clear for patient before starting the treatment when using the PAR index to evaluate the malocclusion severity

Abstract: Aims: To evaluate the effect of microwave disinfection on transverse strength and hardness of acrylic resin denture base materials. Materials and methods: The samples were 112 samples (56 heat cured acrylic resin and 56 microwave cured acrylic resin) they were prepared in dimensions of 65± 0.3x10±0.03x2.5 ±0.03 mm (length, width and thickness respectively) for transverse strength test and 30x15x3±0.03 mm (length, width and thickness respectively) for indentation hardness test. The samples were divided into seven disinfection groups; each one contain five samples which were (control, 900 W or 540W for 3min either inside glass flask containing 150 ml of distilled water)or along with glass flask containing 150 ml of distilled water or alone. The collected data were analyzed using analy-sis of variance (one way ANOVA) at P ≤ 0.05 and Duncan's multiple range test. Results: the transverse strength of microwave acrylic resin samples were significantly decreased except samples that disinfect-ed by 540 watt microwave energy for 3 minute with water inside microwave oven. The hardness number for heat cured acrylic denture base showed no significant differences compared to control group while hardness number of microwave acrylic resin were significantly decreased in relation to control group. Conclusions: Transverse strength of microwave acrylic resin that disinfected with microwave was decreased except at 540 watt for 3 minutes with water a side in microwave oven. While heat cured acrylic resin after microwave disinfection was significantly increased compared with the control sample. Rockwell hardness number for microwave acrylic resin significantly decrease in relation to control group; while for heat cured acrylic denture base showed no significancy comparing with the control group.

Abstract: Aims: To evaluate the effect of different curing methods on tensile bond strength between soft acrylic liner and heat cured acrylic resin denture base. Materials and methods: Twenty four specimens were prepared form Vertex heat cured acrylic resin and divided into four groups: cured by water bath ,treated by monomer and cured by water bath ,cured by domestic microwave oven and treated by monomer and the last group cured by domestic microwave oven at same setting. Instron tensile testing machine was used for tensile bond strength test . Results: There is a significant differences between tensile bond strength of tested groups (p=0.001) for the different curing methods. Conclusions: The curing of soft acrylic liner by water bath had better tensile bond strength compared to microwave curing.

Abstract: Aims: To study the effects of both diabetes mellitus and oral hypoglycemic drugs (metfomin) on sali-vary flow rate and total protein levels of saliva and to compare them with control healthy subjects and to determine their effects on oral health of these patients. Materials and Methods: This study was carried out on 45 individuals (27 males and 18 females); 15 individuals of them were healthy subjects and considered as control group. The second group which comprised 15 patients with diabetes mellitus and received no any treatment (uncontrolled).The third group, diabetic patients were treated with met-formin only. Subjects were selected from the out patients attending Oral Surgery Department, College of Dentistry-University of Mosul. The samples of saliva were collected and salivary flow rates and total protein was determined for each individual, then its relation to oral health was measured accord-ing to Simplified Oral Hygiene Index by Greene and Vermillion. Results: One way analysis of variance was performed and showed that their were significant differences among all study groups for both sali-vary flow rate and total salivary protein concentration .The results of Duncan's Multiple analysis range test showed that there were no significant differences in salivary flow rates and total salivary protein concentrations between first and third groups while significant differences were seen between first and second and between second and third groups .For oral health scores , there was no significant differ-ences between first and third groups while significant differences were observed between first and se-cond and between second and third groups. Conclusions: Changes in salivary flow rates and salivary protein concentrations can result from diabetes mellitus which can affect oral health of these patients, while oral hypoglycemic drugs had no such effects

Abstract: Aims: To evaluate pH, viscosity and retentive ability of modified adhesive materials and compared it with commercially available adhesive materials. Materials and Methods: The pH–value of 0.25% denture adhesive materials were determined using pH meter. The viscosity was determined by Ostwald viscometer (Aldrich Company). The retentive ability was measured by specially manufactured reten-tion testing machine using an acrylic resin disc samples which have 6cm diameter and 3mm thickness prepared from a special mold. Results: The findings of the present study showed that the "Bonyplus" gave the highest pH values of all materials tested. Also, showed that the "CMC” gave the highest vis-cosity values, while "Bonyplus" gave the lowest one. The "CMC" gave the highest retention while the "Distilled water" gave the lowest one. Conclusions: All denture adhesive materials tested have a pH equal to that of neutral. The viscosity test showed that the newly prepared materials have a higher vis-cosity than commercial denture adhesive materials. The retention test showed that the newly prepared materials have a higher efficiency than commercial denture adhesive materials.

Abstract: Aims: To evaluate the antimicrobial effect of the ethanolic extracts of Ruta graveolens (Rue) and Sal-via officinalis (Sage) in a concentration of 0.2% and compare the results with the same concentration of chlorhexidine 0.2% (CHX) and normal saline on root canal bacteria using the above plant extracts as an irrigating solutions clinically. Materials and Methods: Thirty five uniradicular teeth with necrotic pulps were chosen. The patients were divided randomly into four groups, 10 patients for groups I, II and III and 5 patients for group IV. Using 0.2% ethanolic extract of Sage, 0.2% ethanolic extract of Rue, 0.2% chlorhexidine gluconate (CHX) and normal saline, respectively. Samples were obtained from the canal at the beginning of the first and second appointments, at the end of the second appoint-ment and at the beginning of the third appointment using wet sterile paper points. Results: The results revealed that 0.2% of the ethanolic extract of both Sage and Rue have a significant antimicrobial effect when used clinically as an endodontic irrigant, and was significantly not different from 0.2% chlorhex-idine gluconate (CHX) and significantly different from normal saline. Conclusions: Rue and Sage demonstrated antimicrobial effects on the root canal bacteria (both aerobic and anaerobic) used as en-dodontic irrigants compared with CHX.

Abstract: Aims: To measure the amount of permanent deformation of different types of orthodontic arch wires and to study the effect of both time interval and simulated oral environment on amount of permanent deformation of different types of nickel titanium and stainless steel orthodontic arch wires. Materials and Methods: The sample consisted of five types of orthodontic arch wires (extra spring hard stainless steel , spring hard stainless steel, multi strand stainless steel ,nitinol nickel titanium and super elastic nickel titanium), 0.016 inch of round section were deflected into orthodontic brackets fitted in acrylic models put in a closely packed glass container and 200 ml artificial saliva added to them and the sam-ples stored in incubator at 37 °C . At the end of incubation period, the acrylic block take and the wire deactivated and the amount of permanent deformation measured by using Stereo microscope. The results were subjected to the descriptive statistics and to the ANOVA and Duncan’s Multiple Range Analysis Tests to detect the changes among these groups. Results The findings of the present study showed that spring hard stainless steel wires at 28 days gave rise to the highest mean values of perma-nent deformation, while the super elastic wires at 1hr gave rise to the lowest one. The remaining groups distributed on statistical levels of significant difference (P ≤ 0.05) between the upper and lower levels. Conclusions: The super elastic nickel titanium wires exhibited better spring back characteristics and less permanent deformation than the stainless steel. Several wires increased deformation as deflection time increased in simulated oral environment.

Abstract: Aims: The aim of this study was to evaluate the clinical effects of systemic azithromycin as an adjunct to scaling and root planning (SRP) and compared it with metronidazole in the treatment of chronic per-iodontitis. Materials and Methods: Forty four patients with clinical diagnosis of chronic periodontitis underwent scaling and root planing were divided into three groups. The first group (n = 20) patients received azithromycin 500 mg once daily for 3 days plus SRP. The second group (n= 11) received met-ronidazole 500 mg 3 times daily for 7 days plus SRP. The third control group (n= 13) patient received SRP plus placebo treatment once daily for 3 days. Clinical measurement including gingival index, bleeding on probing and probing pocket depth were performed at the base line visit and 40 days after taking the treatment. Results: The results obtained at 40 days from the base line showed better signifi-cant improvement in all clinical parameters (p≤ 0.05) in the treated groups, except for bleeding on probing in control group were no significant improvement was reported. Azithromycin plus SRP give the greatest improvement in mean gingival index and bleeding on probing (p< 0.05) when compared with the control group but no significant differences were observed between metronidazole treated group and the control group. Conclusions: The adjunctive use of azithromycin with SRP has potential to improve periodontal health over SRP only and could be an interesting alternative to metronidazole from patients with chronic periodontitis

Abstract: Aims: To investigate the effect of atenolol drug on the formation and development of rat dentition of rat (histologically and histochemically). Materials and Methods: Albino Wister rats were divided into two main groups,. The control group and experimental group, each consisted of (9) pregnant rats, giv-en 1 ml distilled water and 10 mg atenolol (powder) suspended in 1ml distilled water , orally , as a single dose, respectively from 12 – 18 day of gestation, after delivery of pregnanent rats, 36 newborn were selected to be scarified at ages 1, 5. and 10 post nataly from each group. The specimens were pre-pared for processing and stained with H&E and alcian blue stains. Results: The treated groups showed obvious histological changes: delay in tooth germ formation, increase blood vascularity, disorganiza-tion of ameloblast and odontoblast cells, and delay in glycosaminoglycan synthesis. Conclusions: Atenolol drug delay the rat tooth development causing abnormal odontogenic changes and inhibits gly-cosaminoglycan synthesis.

Abstract: Aims: The purpose of this study is to determine the antimicrobial activity of aqueous and alcoholic extract of grapefruit (Citrus Paradisi Rutaceae) seeds. Materials and Methods: Aqueous and alcoholic (ethanol) extracts of grapefruit seeds "GSE" in 20% (w/v) concentration were investigated for activity against Staphylococcus aureus, Proteus vulgaris, Klebsiella pneumonia, Candida albicans and a mixed oral flora. The level of antimicrobial effects was established using in vitro disc diffusion method. Their antibacterial and antifungal activity was compared to the activity of Chlorhexidine (CHX) solution in two concentrations (0.12 and 0.2%) as a control. Results: The aqueous GSE (20%) solution used in this study gave positive results with lethal effect on the tested organisms with zones of inhibition ranging from 10mm-18mm in diameter, which is comparable to that of chlorhexidine (7mm - 22mm) and (13mm - 20mm) for 0.12% and 0.2% solutions respectively. Ethanolic GSE did not show any antimi-crobial activity. Conclusions: Aqueous GSE has a good antimicrobial effect, which makes it a good natural preparation for use as antiseptic or disinfectant.

Abstract: Aims: To evaluate the effect of two types of disinfectant solutions(2% alkaline glutaraldehyde, 1% sodium hypochlorite) in wettability of three types of elastomeric impression materials (light body) which are used in crown and bridge restorations at different times of immersion. Materials and meth-ods: Three types of elastomeric impression materials (light body) were formed on a flat acrylic resin block and allowed to set(five specimens of each impression material was done for each immersion time(15,30 and 60 minutes)of each disinfectant solution in addition to control groups). The wettability is indicated by measuring the contact angle of aqueous solution of CaSO4 on surface of cured impres-sion materials. Results: indicated no significant effect of immersion times on wettability of three types of impression materials. The hydrophilic type produce high wettability. Conclusions: The disinfectant solutions have different effects on each impression material. Sodium hypochlorite has the greatest ben-eficial effect on wettability.

Abstract: Aims: To evaluate and compare the effect of micro etcher model II on geometrical integrity of base of variable types of orthodontic brackets after etching and compared with new bracket. Materials and Methods: Twenty seven brackets were divided into three groups of nine. Group one was titanium brackets, group two was stainless steel brackets and group three was ceramic brackets. Brackets had been previously bonded to glass slide with same adhesives. All groups were carefully removed with debonding plier and again all groups cleaned from the adhesive material by microetcher and the bases of all brackets examined with stereomicroscope and compared with control group. Results: There are significant differences between the control group and reconditioning groups "stainless steel, pure tita-nium and ceramic brackets". While, the stainless steel and ceramic groups have the lower percentage of deformity in geometrical integrity. Also, the reconditioned groups showed no significant difference among them.Conclusions: This study showed that the microetcher can be used for reconditioning for all types of orthodontic bracket bases; however, minimal damaging may be occurring in orthodontic bracket. Microetcher plays a role in roughness of base of orthodontic bracket.

Abstract: Aims: The aims of the study are to find the incidences, types, sides and sites of mandibular fracture accompanied with head injuries in Ninavah Governorate. Materials and Methods: Data of trauma cases were collected from general, local, private hospitals and health sectors in Ninavah Governorate with a head injury and mandibular fracture for one year duration from June 2006 to May 2007. Age, etiology, types, hospitals, sides and sites, distribution were arranged in tables, chi square and P value used for statistic analysis. Results: The total number of head injury cases was (5828). The total num-ber of fractures mandible with and without head injury was (282) cases means (4.84%) of total number of head injury cases, while mandibular fracture with head injury cases incidence was (76) cases (1.3%) of total number of head injury cases . Conclusions: Children were the most common age group affect-ed by head injury, while geriatric age group was the least. Male showed high percentage than female in a ratio about 2:1. Low incidence of association between head injury and fracture mandible which means that there is no need for delaying maxillofacial treatment. Falls from height and bullet injuries were the common cause of head injury and fracture mandible (dentoalveolar fractures showed high incidence followed by body fractures).

Abstract: Aims of the study: The study aims to evaluate the effect of naproxen and ibuprofen on post maxillo-mandibular fixation (MMF) limited mouth opening. Materials and Methods: The study was per-formed at AL-Jumhoori Teaching Hospital in Mosul City on 30 patients with mandibular fracture and or maxilla who were treated with MMF. The medicaments were allocated to 30 patients using a double blind randomization study who were divided into three groups .Group 1(10 patients) received Ibu-profen. Group 2(10 patients) received Naproxen and Group 3 (10 patients) received placebo . Immedi-ately after MMF release, the maximum mouth opening was measured as the inter-incisal distance be-tween the right upper central incisor and the right lower central incisor. After one hour ,the inter incisal distance was measured again and recorded .The data were analyzed using paired T-test and Duncan multiple analysis. Results: Both Naproxen and Ibuprofen have a statistically significant effect on the improvement of post-MMF limited mouth opening compared to placebo . At the same time there was no significant difference between the effect of Naproxen and that of Ibuprofen on the improvement of post MMF-limited mouth opening .The study also showed that there is inverse correlation between the MMF period and the maximum mouth opening immediately after MMF release. Conclusions: There is no significant difference between the effect of naproxen and that of ibuprofen on the improvement of limited mouth opening after MMF release. The available and cheaper drugs can be prescribed.

Abstract: Aims: The aim of this retrospective clinical trial was to evaluate and compare the upper and lower first molar apicectomy procedures in terms based on certain clinical criteria selected. Materials and Meth-ods: This clinical trial was conducted at the Department of Oral and Maxillofacial Surgery / College of Dentistry / University of Mosul. The sample recruited was composed of forty healthy subjects who required apicectomy procedures on either an upper or lower fist molar. The sample was subdivided into two groups of twenty subjects each. The first group comprised those patients where root end resection ( apicectomy ) on an upper first molar tooth was required. The second group included those patients who required an apicectomy procedure on one of their lower first molar tooth . Criteria that were eval-uated and compared included pain, swelling and trismus which were evaluated on the first operative day, second, third and seventh postoperative day. Results: A significant difference was observed be-tween recall visits in regard to the pain level of mandibular procedures and was also observed in maxil-lary procedures. In regard to pain level assessment between mandibular and maxillary procedures, a significant difference was observed with pain levels higher in mandibular procedures for the second and third day when compared to maxillary procedures. A significant difference was observed between recall visits in regard to swelling of soft tissue of mandibular and maxillary procedures. Concerning grade of swelling assessment between mandibular and maxillary procedures, a significant difference was observed with swelling of soft tissue higher in mandibular procedures on the second and third day when compared to maxillary procedures. A significant difference was observed for limitation of mouth opening in mandibular procedures between recall visits specifically on the first and second day but was not observed in maxillary procedures. When comparing between upper and lower surgical procedures, a significant difference was observed in trismus specially on the second and third post-operative day and which was more pronounced in mandibular procedures. Conclusions: It seems that complications following root end resection on lower first molar teeth are more evident when compared to the upper first molar region, but only in the first few days following surgery. However, such complications were tolerable to the patient and can be overcome by medications and exercise. Such complications should not hinder the oral surgeon from performing endodontic surgery on posterior teeth when indicated

Abstract: Aims: The aim of this in vitro study was to evaluate the apical sealing ability of matched-taper Single-cone, Thermafil, and Cold lateral condensation obturations. Materials and Methods: Thirty-six ex-tracted human lower canine teeth were instrumented to size (F3) with ProTaper rotary instruments after cutting of their crowns to the cement-enamel junction CEJ. The working length was determined for each tooth. The teeth were divided into (3) groups (10) of each and (6) teeth were used as a positive and negative control groups. The teeth were obturated with matched-taper Single-cone, Thermafil, and lateral condensation techniques. Tgadseal was used as a root sealer in this study. A die penetration method was used to evaluate the apical seal using a stereomicroscope at 40X magnification. One-way analysis of variance and Duncan's tests were used for statistical analysis. Results: The statistical anal-ysis of the results demonstrated that there was no statistically significant difference in microleakage between the lateral condensation and Thermafil groups. The matched taper single cone showed the least microleakage with a significant difference than the other two groups. Conclusions: The apical sealing ability of Matched-taper Single-cone obturation was better than the lateral condensation and Thermafil techniques when the root canal was prepared using a ProTaper rotary instrumentation.

Abstract: AIMS: to evaluate the effect of microwave post-treatment in the reduction of residual monomer of different types of acrylic resin and evaluate the effect of microwave treatment time. MAERIALS AND MEHODS: three different types of acrylic resin materials are used; heat cured, light cured, and or-thocryl. Specimens are subjected to additional curing with microwave and compared their residual monomer with the control group. ANOVA followed by Duncan multiple range test were used to de-termine the significant difference at P