Distal Aspect Of Second Molar Research Articles

Evaluation of Prevalence and Quality of Root Resorption of Second Molar Adjacent the Impacted Third Molar in Cone-Beam Computed Tomography

Introduction: Impacted third molar reduces the bone level in the distal aspect of second molar, and sometimes it can lead to external root resorption of the adjacent second molar. The aim of this study was to evaluate the prevalence and quality of this resorption using cone-beam computed tomography scanning.
 Materials & Methods: In this descriptive study, CBCT images selected from 60 patients (including 107 maxillary & mandibular impacted third molars) were obtained from patients referring to maxillofacial radiology department of dental faculty of Islamic Azad University of Isfahan (Khorasgan) in 2016. Under observation of oral radiologist, the images were examined (two times with one-week interval) in axial, coronal, and sagittal sections and recorded to diagnose external root resorption in CBCT. The data were analyzed via descriptive statistics including contingency tables and relative abundance.
 Results: The prevalence of external root resorption of second molar, adjacent to the third molar were 43.25%. The most common type of third molar impaction were mesioangular third molars (41.1%) and in the next level were the vertical (28.1%), and distoangular (18.7) and then horizontal (12.1). The most common location of resorption in mandibular second molar teeth was in 1/3 of cervical (62.5%), and then 1/3 of apical (20.8%) and 1/3 of the middle (12.5%). Also one of teeth resorptions (4.2%) was between the 1/3 of apical and 1/3 of the middle. The most common site of resorption in maxillary second molar teeth was at 1/3 of the apical (68.45%), and then at the 1/3 of the middle (17.35%) and 1/3 of cervical (8.7%). With regards to the severity of resorption; 78.96% of resorptions were mild, 12.03% severe, and 9.03 were moderate.
 Conclusion: The prevalence of this type of resorption is almost high and the most common position of impacted third molars that resulted in this type of resorption are mesioangular and horizontal. Most common site of resorption in the maxilla was 1.3 of the apical and in the mandible was 1.3 of the cervical, which were often mild in resorption.

Treatment of periodontal pockets at the distal aspect of mandibular second molar after surgical removal of impacted third molar and application of L-PRF: a split-mouth randomized clinical trial.

Presence of clinical attachment loss on the distal aspect to the second molar may be associated with malposition of the third molar. The aim of this study was to evaluate the reduction of clinical attachment loss at the distal aspect of the second molar after third molar extraction and application of leukocyte- and platelet-rich fibrin (L-PRF). Eighteen subjects with a clinical attachment loss on the distal site to the second molar associated with impacted third molar in both sides of the jaw were recruited for the study. For each subject the teeth were randomly allocated in test and control groups. After surgical removal of the impacted third molar, the L-PRF was inserted in the fresh alveolar socket of test sites; in the control sites no graft was inserted after extraction. Full-mouth plaque score, full-mouth bleeding score, clinical attachment level (CAL), probing depth, and gingival recession were assessed at baseline and 6 months later. After 6 months, mean CAL change was 1.99 ± 1.18 mm in the test group and 1.15 ± 1.01 mm in the control group; probing depth change was 1.33 ± 0.87 mm in the test group and 0.50 ± 0.63 mm in the control group. Statistically significant differences (P < .05) were observed between groups in terms of CAL and probing depth changes. No differences were found in gingival recession changes. Within the limits of the present study, the sites treated by means of application of L-PRF after impacted third molar extraction showed better results in terms of CAL gain and probing depth reduction when compared with control sites.

Mandibular Second Molar Periodontal Parameters after Surgical Extraction of Adjacent Impacted Third Molar

Introdouction: Impacted mandibular third molar surgery may affect periodontal status of the adjacent second molar. The purpose of this study was to evaluate the changes in periodontal health parameters distal to the adjacent second molar following surgical extraction of an impacted mandibular third molar.Materials And Methods We selected 50 subjects with a mean age of 22.8 (ranging from 18 to 25) years, of which 42 completed the study. Patients had no systemic problems and had a mesioangular impacted mandibular third molar categorized at C1 class based on Pell and Greogory classification. PD (Probing Depth) and AL (Attachment Level) were measured before surgery and four months after surgery on the distal aspect of adjacent second molar. Data analyses were conducted by using SPSS Software (Version22) and a probability level of 0.05 was used throughout.The results were analyzed statistically using paired-sample t-test and ANOVA (repeated measures).Results Surgical extraction of fully impacted mesioangular third molar resulted in statistically significant decrease in PD on the distal aspect of mandibular second molar (pConclusion Surgical extraction of mesioangular deeply impacted mandibular third molars causes decreased PD at the distal aspect of the second molar and improves AL. Therefore, periodontal improvement was shown in our study. But further research that reduces the limitations of this study and the use radiographic follow-up can provide better results.

Periodontal healing after ‘orthodontic extraction’ of mandibular third molars: A retrospective cohort study

In this study we investigated periodontal healing of mandibular second molars following ‘orthodontic extraction’ of adjacent impacted third molars, under the null hypothesis that there would be no difference in probing pocket depths (PPD) and clinical attachment levels (CAL) at the distal aspect of second molars before and after treatment. A retrospective survey was conducted of 64 patients who consecutively underwent ‘orthodontic extraction’ of mandibular third molars in close anatomical relationship with the mandibular canal from January 1997 to January 2011. Age, smoking habit, and PPD and CAL at the distal aspect of second molars before and after treatment were recorded. A statistically significant difference was found in PPD and CAL before and after treatment for the overall sample and for the sample classified by age (>25 or ≤25 years), smoking habit (smoker or non-smoker), and type of third molar impaction (horizontal, mesioangular, or vertical). Median PPD and CAL reductions amounted to 6mm and 5mm, respectively. The null hypothesis was rejected and orthodontic extraction proved to be indicated for those impacted mandibular third molars at high risk of a postoperative periodontal defect at the distal aspect of the adjacent second molar.

Use of Lincomycin-Impregnated Demineralized Freeze-Dried Bone Allograft in the Periodontal Defect After Third Molar Surgery

The aim of the present study was to evaluate the periodontal regenerative capacity of demineralized freeze-dried bone allograft (DFDBA) alone or used with local lincomycin. In the present single-blind, randomized, controlled clinical trial, 20 subjects 26 years old or older, requiring extraction of bilateral third molars (M3s), were included. Each subject was randomly assigned to receive either DFDBA or DFDBA plus lincomycin therapy. Within the subjects, 1 M3 site was randomly selected to be the experimental site and the contralateral served as the control and was permitted to heal without intervention. The primary variables were changes in the probing depth (PD), clinical alveolar bone levels (ABLs), and radiographic alveolar bone density (ABD) on the distal aspect of second molar between baseline (immediately postoperatively) and 26 weeks postoperatively (T26). Appropriate sample sizes and descriptive, bivariate, and multivariate statistics were computed. For both treatment and control sites, between T0 and T26, statistically significant improvements were seen in the ABLs and ABD (P < .05). Within-subject comparisons showed no significant differences in PD, ABL, or ABD between the treatment and control M3 sites at T0 or T26 (P > .05). Also, no significant differences were found in the PD, ABL, or ABD between the 2 treatment M3 sites at T26 (P > .05). The results of the present study have revealed that the PD, ABL, and ABD improved after M3 removal in subjects 26 years old or older, irrespective of the treatment or control group. Reconstructive procedures (e.g., DFDBA with or without lincomycin therapy) did not offer predictable benefits compared with a no-treatment protocol in patients younger than 30 years old.

Effects of lower third molar extraction on attachment level and alveolar bone height of the adjacent second molar

Several conflicting findings have been published in previous literature regarding the effects of impacted third molar extraction on the periodontal health of the adjacent second molar; some authors have shown improvement of periodontal health distal to the adjacent second molar, whilst others have demonstrated loss of attachment and reduction of alveolar bone height. The purpose of this controlled clinical and radiographic study is to evaluate the long-term changes in periodontal health and alveolar bone height distal to the adjacent second molar following extraction of an impacted third molar. This split-mouth design study included 25 patients who underwent extraction of one mandibular impacted third molar (test), whereas the opposite tooth remained intact (control). Pre-operative and current-state panoramic radiographs were than scanned, and alveolar bone height was digitally measured on the distal aspect of the second molar on the test and control sides. Current-state clinical measurements were performed on both sides, and consisted of plaque index, gingival index, periodontal pocket depth, gingival margin position and clinical attachment level. Student's t-test for paired observations was used in order to examine the statistical significance of the differences in clinical parameters between the test and control sides and the differences in alveolar bone height pre- and post-operatively on both sides. Extraction of an impacted third molar resulted in a significant gain of alveolar bone height on the distal aspect of the adjacent second molar on the test side, whereas slight bone loss was noted on the control side. Even though the difference in plaque index between the test and control sides approached statistical significance following extraction, all clinical parameters seem to be unchanged. Further follow-up on clinical and radiological parameters is required for a more profound understanding of the long-term effects of third molar extraction on the periodontal health of the adjacent second molar.

Reconstruction of alveolar bone defects after extraction of mandibular third molars: A pilot study

Introduction A documented complication of mandibular third molar extraction is the development of bony defects on the distal aspect of the adjacent second molar. The primary study purpose was to determine the efficacy of grafting third molar extraction sites with demineralized bone powder to prevent the formation of periodontal defects. Material/Methods With a randomized clinical trial study design and a third molar extraction surgical model, we enrolled a study sample composed of patients who required extraction of bilateral third molars. Demineralized bone powder was placed in one randomly selected extraction site per patient. The remaining extraction site served as a control. Patients served as their own controls. To assess periodontal healing, we measured plaque and gingival indexes and periodontal attachment loss on the distobuccal aspect of the adjacent second molar preoperatively and 6 months postoperatively. Results Of 14 patients enrolled, 7 patients with a mean age of 21.7±3.7 years completed the study protocol. No statistically significant differences were noted between patients who did and did not complete the study protocol (all p values ≥0.42). There were no statistically significant differences for the various anatomic, operative, or periodontal measures between the control and treatment teeth preoperatively (all p values ≥0.46). Six months postoperatively, there were no statistically significant changes in the plaque or gingival indexes for the control or experimental sites. At the control sites, there was a nonstatistically significant decrease in mean attachment loss from 3.1±1.3 mm preoperatively to 1.4±1.6 mm 6 months postoperatively ( p=0.06). At experimental sites, there was a statistically significant decrease in mean attachment loss from 3.3±1.4 mm preoperatively to 0.6±0.8 mm 6 months postoperatively ( p=0.02). Conclusions The study results suggest that demineralized bone powder may decrease attachment loss on the distal aspect of the second molar after extraction of the adjacent third molar. Additional studies are indicated to confirm the results of this pilot study. We recommend that future studies limit their study samples to patients at high risk for developing periodontal defects after third molar extraction.