Journal of Dental Medicine

Background and Aims: The structural distinction of primary teeth compared to the permanent teeth leads to a faster penetration of the caries into the pulp, which makes effective treatment necessary. The aim of this study was to determine the success rate of pulpotomy in primary molar teeth and its effective factors using formocresol by students and residents at the department of pediatric dentistry of Hamedan dental school.
Materials and Methods: In this cross-sectional study, 113 children who previously had pulpotomy by formecresol in their primary molars (30 children by residents and 83 children by the students) were randomly evaluated based on referral time (at least 12 months after treatment) in terms of clinical and radiographic success rates. Data were analyzed by SPSS20 software using Chi-square and descriptive statistics.
Results: The success of the pulpotomy of primary molar teeth was 81.7%. The success rates of the general students and residents were 79.3% and 87.3%, respectively. The percentage of successful pulpotomy was significantly higher in general students at Stainless Steel Crown (S.S.C), second molar in maxilla (P<0.05), but did not have a significant relationship with age and sex (P>0.05). The percentage of pulpotomy success performed by residents did not have a significant correlation with gender, age, type of repair, type of teeth and jaws (P>0.05). In general, the percentage of success in S.S.C, the second molar and maxillary jaw was higher. Also, the success rate of pulpotomy by residents was significantly higher than that of general- students (P<0.05). The highest rates of pulpotomy failure were related to internal analysis.
Conclusion: Formocresol pulpotomy using S.S.C in the maxillary second molar teeth had higher success rate.

Background and Aims: Immediate implant placement following tooth extraction is a treatment with many advantages. Alveolar bone preservation after immediate implant, need minimum of 2 mm thickness in buccal bone plate. The aim of this study was to evaluate the thickness of buccal cortical bone of maxillary premolars by Cone Beam Computational Tomography (CBCT) technique.
Materials and Methods: In this descriptive epidemiological study, Cone Beam Computed Tomography image was obtained from 29 patients (male and female) referred to the radiology department of Jundi Shapoor dental school of Ahvaz from 1393 (Mehr) to 1394 (Shahrivar) for implant insertion insertion. The thickness of buccal cortical bone was measured in 3 and 5 mm apical to the CEJ and root apex, perpendicular to the longitudinal axis. All the measurements were done by two oral and maxillofacial radiologists, separately. Data were analyzed by SPSS22 software, using descriptive statistics, and T-test.
Results: The thickness of buccal cortical bone in second premolar was significantly more than 1 mm (P=0.001), but in first premolar, the thickness was close to 1 mm with a non-significant difference (P=0.29).
Conclusion: The results of this study showed that immediate implant insertion could be done in the maxillary second premolar area with more predictability compared to the first premolar area.

Background and Aims: Knowing the depth and type of the teeth impaction with radiographic approaches can guide the clinicians into selecting the most appropriate treatment and prevent surgical complications. Therefore, the purpose of this article was to evaluate the prevalence of canine and premolar impaction in the digital panoramic view of patients referred to Rasht dental school in 2019.
Materials and Methods: This annalistic-descriptive cross-sectional study comprised patients who attended the Faculty of Dentistry, Rasht, Iran in 2019. Dental records and panoramic radiographs of 500 patients were reviewed retrospectively. Demographic information as well as the type and depth of impaction, involved jaw, and also, the associated pathological lesions were recorded. Data were analyzed with SPSS24 version with significant level of P<0.05.
Results: The findings revealed that among 500 individuals (300 (60%) were females and 200 (40%) were males), 35 individuals (7%) had at least one impacted tooth, 80% of impacted teeth were canines and the others were premolars. The most common impaction type, impaction level, and pathological lesion were mesioangular, B, and carries of the adjacent tooth, respectively. A significant relation was not observed between the type and level of impaction with the involved jaw (P=0.15, P=0.99) and also, the relation between the type of pathological lesion and gender was insignificant (P=0.85).
Conclusion: Functional and esthetic complications of impacted tooth can be prevented or declined by on-time radiographic screening.

Background and Aims: The surgical removal of mandibular third molar is frequently accompanied by significant postsurgical complications, and different protocols have been described to decrease such complications. The aim of this study was to compare the postoperative complications of mandibular impacted third molar removal with two conventional rotary and piezoelectric methods.
Materials and Methods: In this study 27 patients with bilateral mandibular impacted third molars were selected. The patients’ teeth were extracted by the piezoelectric method on a random side and the opposite tooth was extracted by conventional rotary technique. On operation and post operation days, edema, pain, and mouth opening were assessed. The duration of each operation was also measured. Data were analyzed by Mann-Whitney test and independent t-test.
Results: The mean duration of operation in the rotary group was less than that of the piezoelectric group, which was statistically significant (P=0.001). Pain was significantly higher in the rotary group on days 0 to 5 (P<0.05). Whereas, difference in pain on day 6 was not statistically significant (P=0.067). There was no significant difference between the two groups in each day after surgery regarding mouth opening (P>0.05). Edema was significantly higher in the rotary group on the first, third, and fifth days after surgery (P<0.05). Also, edema was higher in the rotary group on the seventh day after surgery, but not statistically significant (P=0.076).
Conclusion: According to the results of the present study, it can be concluded that pain and swelling in patients after impacted tooth surgery using time consuming piezoelectric technique can be reduced.

Background and Aims: Mandibular third molar is the most common impacted tooth and craniofacial morphology and facial parameters can be appropriate predictors of impaction of this tooth. The aim of this study was to evaluate the relationship between Gonial angle, mandibular plane inclination, and ramus height with the impaction of mandibular third molar.
Materials and Methods: This retrospective descriptive-analytical study was performed by analysis of lateral cephalometric radiographic images of 172 patients in city of Zahedan in 2020. The status of eruption of mandibular third molars was determined by clinical examination and assistance of panoramic radiographic images and samples were categorized into four groups: fully erupted (1), partially impacted (2), impacted (3), partially developed (4). Then, the Gonial angle, mandibular plane, and ramus height were measured on lateral cephalometric images of each group and collected data were analyzed by Chi-square test and analysis of variance (ANOVA).
Results: Among the patients, 68.02% were female and 31.97% were male. The difference between the mean values of Gonial angle of four groups was not statistically significant (P>0.05). In the fourth group, the mean value of mandibular plane inclination was significantly higher (29.74) and the mean value of the ramus height was significantly less (49.21 mm) than other groups.
Conclusion: According to the preformed analysis and obtained results, Gonial angle, mandibular plane, and ramus height were not accurate predictors for the impaction of mandibular third molar and further studies should be undertaken in this filed.

Background and Aims: To be successful in root canal therapy, the dentists must be aware of the possible variation in the root canal and should know not only the natural anatomy of the pulp, but also a variety of possible morphologies. Frst of all, the dentists should be familiar with the possible anatomy of the root canal and then with the extraction of organic tissue from pulp chamber and root canal, increasing the chances of treatment success. Therefore, in this study, we decided to investigate the internal anatomy of root canals in the maxillary permanent molar teeth in Khoy city. Materials and Methods: In this in vitro study, 100 extracted human molars in Khoy city in West Azerbaijan province were collected. In all teeth, the access cavities were prepared, then they were decalcified and colored with India ink and evaluated by clearing technique. Data were collected based on Vertucci's classification which entered into SPSS23 software. The descriptive statistics in the form of numbers and percentages in tables and graphs were used to analyze the data. Results: The most common type observed in the mesiobuccal root of the first molars was type IV by 44%, in distobuccal root was type I by 92%, and in palatal root was type I by 94%. Also, in the mesiobuccal root of the second molars, the most common type was type I by 70%, in distobuccal root was type I by 94%, and in palatal root was type I by 96%. Conclusion: The mesiobuccal root of the first molar had the most variation in the internal anatomy. Also, the most common type of Vertucci in the mesiobuccal root of first molar was type IV and in the other roots of the first and second molar teeth was type I.

Background and Aims: Third molar teeth extraction is one of the common treatments procedure in dentistry. The proximity of mandibular third molar teeth to the inferior alveolar nerve canal may make the surgery challenging and cause adverse complications. The purpose of this study was to determine the accuracy of diagnostic and evaluation of panoramic radiography findings in two classification methods (Rood-Shehab and Tanaka) according to CBCT in mandibular third molar extraction surgery.
Materials and Methods: This cross-sectional analytical study was conducted on 65 patients of a private radiology clinic in Qom who had simultaneous panoramic and CBCT radiography. Panoramic and CBCT radiographs were imported into Scanora and Ondemand softwares, respectively. The relation of the mandibular third molar with the inferior alveolar nerve was evaluated according to Tanaka's classification and Rood-Shehab radiographic signs and compared with CBCT radiographs. Finally, the obtained data were analyzed by chi-square test, ROC curve and SPSS software version 24. The significant level was considered at P<0.05.
Results: Out of 65 samples, 23.1% were men and 76.9% were women. The mean age of participants was 26.9±8.77. There was a significant relation between the Tanaka's classification of panoramic radiographs and proximity to the nerve in CBCT radiographs (P=0.011). This relationship was significant when the number of radiographic signs of the Rood-Shehab classification increased (P=0.044). Root darkening and diversion of mandibular nerve canal signs of Rood-Shehab classification showed more diagnostic accuracy in the nerve canal contact determination than that of other signs.
Conclusion: The probability of contact of third molar root with the inferior alveolar nerve canal increases with increasing in the number of Rood-Shehab radiographic signs. The root darkening sign was more accurate and followed by mandibular canal diversion sign. Tanaka’s classification can be used in differentiating cases without contact to the nerve canal.

Background and Aims: Bimaxillary dentoalveolar protrusion (BDP) is a common orthodontic anomaly characterized by protrusive dental arches and lip prominence. Extraction of the first premolars is a frequently employed treatment approach in these patients. However, the effect of this intervention on Bolton ratios-particularly the overall and anterior ratios-remains unclear. This study aimed to evaluate the impact of first premolar extractions on Bolton ratios in patients with BDP.
Materials and Methods: This experimental study was conducted on archived physical models of 34 Class I patients with BDP and functional lip incompetency (>4 mm) accompanied by lip protrusion, available at the Orthodontics Department of School of Dentistry, Babol, in 2024. All patients had a full complement of teeth from the first incisor to the first molar in each quadrant. After digitizing the models, mesiodistal tooth widths and the overall and anterior Bolton ratios were calculated. Digital simulation of first premolar extraction was performed, followed by reassessment of Bolton ratios. Pre- and post-treatment values were statistically compared using paired t-tests in SPSS (significance level set at 0.05).
Results: Among 34 studied casts, 67.6 % belonged to females. The mean overall Bolton ratio decreased significantly from 90.33 ± 2.23% to 87.72 ± 2.39%, and the anterior ratio declined from 78.19 ± 2.96% to 77.85 ± 3.03% (P<0.001). Additionally, 15 patients exhibited residual space post-treatment, primarily in the mandibular arch.
Conclusion: Based on the results of the present study, first premolar extraction significantly reduced both the overall and anterior Bolton ratios in patients with bimaxillary dentoalveolar protrusion. However, the likelihood of residual space—particularly in the lower arch-should be carefully considered during orthodontic treatment planning to ensure long-term stability and success.