Patient, radiological, and operative factors associated with surgical difficulty in the extraction of third molars: a systematic review

Prediction of extraction difficulty for impacted maxillary third molars with deep learning approach

OBJECTIVE

The aim of this study is to determine if a deep learning (DL) model can predict the surgical difficulty for impacted maxillary third molar tooth using panoramic images before surgery.

MATERIALS AND METHODS

The dataset consists of 708 panoramic radiographs of the patients who applied to the Oral and Maxillofacial Surgery Clinic for various reasons. Each maxillary third molar difficulty was scored based on dept (V), angulation (H), relation with maxillary sinus (S), and relation with ramus (R) on panoramic images. The YoloV5x architecture was used to perform automatic segmentation and classification. To prevent re-testing of images, participate in the training, the data set was subdivided as: 80 % training, 10 % validation, and 10 % test group.

RESULTS

Impacted Upper Third Molar Segmentation model showed best success on sensitivity, precision and F1 score with 0,9705, 0,9428 and 0,9565, respectively. S-model had a lesser sensitivity, precision and F1 score than the other models with 0,8974, 0,6194, 0,7329, respectively.

CONCLUSION

The results showed that the proposed DL model could be effective for predicting the surgical difficulty of an impacted maxillary third molar tooth using panoramic radiographs and this approach might help as a decision support mechanism for the clinicians in peri‑surgical period.

Is the third molar the most frequently extracted tooth? A population-based study utilizing dental panoramic radiographs in adults

OBJECTIVES

The study aimed to examine the authenticity of the often-mentioned statement that the third molar is the most frequently extracted tooth. This finding has not been shown previously in a large population-based sample.

MATERIALS AND METHODS

Data comprised a nationally representative sample of 6082 panoramic radiographs taken from adults in the cross-sectional Health 2000 Survey. From the radiographs, all missing teeth were recorded. Information on congenital agenesis of individual teeth was retrieved from two published meta-analyses. Primary outcome was the frequency of missing teeth by tooth type. Explanatory variables were age, sex, and the jaw (maxilla/mandible). Statistical analyses included χ2 test and binomial logistic regression.

RESULTS

Mean age of participants (46% men, 54% women) was 53 years (SD 14.6; range 30‒97 years). Missing teeth occurred more often in women than in men (P < 0.001). The third molar was most frequently missing and the canine least frequently. In the maxilla and mandible, the third molar was missing more often than each of the other tooth types up to the age of 80 years (P < 0.01).

CONCLUSIONS

When considering the rates of congenital agenesis of individual teeth, it is concluded that the third molar remained the most common tooth extracted up till the age of 80 years.

CLINICAL RELEVANCE

The third molar is the most common target for extraction, but also the most common tooth associated with malpractice claims, and therefore, calls for skills, adequate equipment, and other resources for a successful extraction.

Surgical difficulty and postoperative course of the third molar extraction under general anesthesia: An intervention trial

BACKGROUND

Third molar extractions are one of the most common surgical procedures in the area of ​​stomatology. However, we know that even if they are minor surgeries, they can cause a postoperative period with local and systemic repercussions. Thus, the aim of this intervention trial is to determine the relationship between clinical parameters (pain, inflammation and trismus) and serum parameters (C-reactive protein (CRP), IL-6 and fibrinogen) that are modified in the first postoperative week, and the appearance of complications after extraction with general anesthesia, using the Pederson scale.

METHODS

The research question was: Can postoperative discomfort after third molar extraction under general anesthesia be predicted using Pederson scale? An interventional trial was carried out of third molar extractions under general anesthesia in Dr. Peset University Hospital. Patient selection was performed randomized using MS Excel. Then were divided into two groups (n = 126): group A (2 complex extractions) and group B (4 extractions: 2 simple and 2 complex). All parameters were collected at the surgery and 7 days after surgery.

RESULTS

The clinical postoperative parameters showed significant differences in relation to surgical difficulty. In summary, the degree of surgical difficulty can be predicted with the Pederson scale before extracting mandibular third molars. CRP and fibrinogen levels increase significantly with the degree of surgical difficulty.

CONCLUSION

Significant differences (p < 0.001) were observed in all the intraoperative parameters according to surgical difficulty as assessed by the Pederson scale. Therefore, this scale was a good indicator to estimate the patient's postoperative period.

[Low power laser as an adjuvant to paresthesia. report of two cases]

Tooth extraction or extraction is a common procedure in dental practice, although it is a common practice, it is not exempt from complications. Paraesthesia is defined as a neuropathy with altered sensations and permanent anesthesia. The case of two patients who attended the Department of Pathology at the Faculty of Dentistry with paresthesia is reported. Both were treated with low-power laser therapy, showing a significant improvement in their clinical condition. The application of low-power laser presents ideal benefits in various areas of the stomatological field. As it is a non-invasive, painless treatment and short sessions, the patient is encouraged to continue with the treatment until they are almost completely rehabilitated.

Level of difficulty of tooth extractions among roughly 100,000 procedures in primary care

OBJECTIVES

The study examined treatment codes of extracted teeth and aimed to assess degree of difficulty concerning all tooth extractions.

MATERIALS AND METHODS

Retrospective data on treatment codes of all tooth extractions during a two-year period were obtained from the patient register in primary oral healthcare of the City of Helsinki, Finland. Prevalence, indication, and method of extraction appeared in the treatment codes (EBA-codes). Degree of difficulty was determined from the method and classified as non-operative or operative and as routine or demanding. Statistics included frequencies, percentages, and χ2 test.

RESULTS

Total number of extraction procedures was 97,276, including 121,342 extracted teeth. The most frequent procedure was a routine extraction of a tooth with forceps (55%, n = 53,642). The main reason for extraction was caries (27%, n = 20,889). Of the extractions, 79% (n = 76,435) were non-operative, 13% (n = 12,819) operative, and 8% (n = 8,022) multiple extractions in one visit. Level of difficulty was distributed as routine non-operative (63%), demanding non-operative (15%), routine operative (12%), demanding operative (2%), and multiple extractions (8%).

CONCLUSIONS

Two-thirds of all tooth extractions in primary care were relatively simple. However, 29% of procedures were classified as demanding.

CLINICAL RELEVANCE

As earlier methods for assessing level of difficulty were aimed at third molars alone, an analysis was presented for all tooth extractions. This approach may be useful for research purposes, and the profile of tooth extractions and their difficulty level may be practical also for decision-makers in primary care.

Mandibular third molar extraction: perceived surgical difficulty in relation to professional training

BACKGROUND

Establishing the level of surgical difficulty pre-operatively is an essential step in ensuring correct treatment planning. This study set out to determine whether the knowledge and experience acquired by dentists who had received different levels of training influenced, firstly, the perceived levels of difficulty of a variety of cases of mandibular third molar (MTM) extraction and, secondly, the perceived difficulty deriving from a series of factors (patient-related factors, anatomical and radiographic factors, operative factors).

METHODS

This cross-sectional, descriptive, observational study took the form of a survey. Using a visual analog scale (VAS), participants evaluated both the perceived difficulty of 30 cases of MTM extraction described by means of digital panoramic radiographs and the perceived difficulty deriving from a series of factors conditioning MTM extraction. The results underwent statistical analysis with SPSS Statistics 28.0 software. Non-parametric tests (Mann Whitney test for independent samples and the Kruskal-Wallis test) were applied.

RESULTS

A total of 389 surveys were available for analysis. Dental practioners with no surgical training saw the intervention as presenting greater difficulty. Professionals with postgraduate training in oral surgery considered patient-related factors more important than operative factors, in contrast to dentists who had not received oral surgery training.

CONCLUSIONS

Dental training has a signficant influence on the perceived difficulty of MTM extraction and also affects opinions about which factors have greater or lesser influence on surgical difficulty.

Does the Tooth Sectioning Method Impact Surgical Removal of the Distoangular Impacted Mandibular Third Molar?

PURPOSE

Distoangular impacted teeth are considered challenging to remove due to their anatomic position. Proper tooth sectioning ensures the removal with minimal bone removal. This study aimed to compare the outcomes of 2 different tooth sectioning methods.

MATERIALS AND METHODS

Patients with distoangular-impacted mandibular third molar were included in this single-blinded randomized controlled trial. Patients with Class III-impacted, grossly decayed teeth and who were ASA III and above were excluded. The subjects were randomly allocated into Group-A conventional method, where tooth sectioning at the cementoenamel junction, and Group B, the modified method, where tooth sectioning removes only the distal portion of the crown. The primary predictor variable was the tooth sectioning method. The primary outcome variable was the operative time and the secondary outcomes included postoperative pain, trismus, and edema assessed on postoperative days 3 and 7. The effect of treatment on operative time was assessed using a t-test and Chi-squared test was used to compare the categorical data.

RESULTS

Thirty eight patients were included in this study. With a 1:1 allocation ratio, 18 (50%) patients were included in each group. No statistically significant differences were observed in the 2 groups for gender allocation (P = .32), age (P = .34), tooth classification (P = .97), and side of extraction (P = .32). The mean operative time was 31.61 ± 14.13 minutes for group A and 22.72 ± 10.79 minutes for group B, at the 95% confidence interval had a P value of .04 (P < .05), favoring group B. Secondary outcomes of pain measured by visual analogue scale 3.83 ± 3.06 for group A and 3.88 ± 3.06 for group B (P = .95), facial edema 22.79 ± 2.08 and 22.88 ± 1.32, respectively (P = .88), and the maximal interincisal opening of 33 ± 8.59 and 31.33 ± 7.42 on day 3 (P = .54) and 36.16 ± 11.62 and 39.05 ± 6.08 on day 7 (P = .36). However, the difference in need for rescue analgesia 2.05 ± 2.15 and 0.44 ± 0.85 (P < .01) was statistically significant, suggesting the superiority of the conventional sectioning method.

CONCLUSIONS

The results show that both methods of tooth sectioning yield comparably acceptable results. However, the tooth removal was faster by the modified sectioning and the need for rescue analgesia was minimal in this group, suggesting it to be a preferred technique over the conventional method.

Advantages of Sedation With Remimazolam Compared to Midazolam for the Removal of Impacted Tooth in Patients With Dental Anxiety

PURPOSE

Although midazolam is commonly used to sedate patients with dental anxiety, it has shortcomings that reduce the satisfaction of patients and doctors. The aim of this study was therefore to explore the advantages of remimazolam as a sedative.

METHODS

The study design was a prospective randomized controlled trial. Patients with dental anxiety and who were to undergo impacted tooth removal were randomized into remimazolam and midazolam groups. They were sedated with remimazolam or midazolam prior to receiving nerve blocker. The predictor variable was the type of sedative, while the primary outcome variables were the onset time, awakening time, recovery time, and postoperative side effects. Secondary outcome variables were the Modified Dental Anxiety Scale score before and after surgery, patient satisfaction and comfort levels scores, and doctor satisfaction level scores. Other variables included the patient demographics and the operation time. Data were analyzed using the Student's t-test, Mann-Whitney test, χ² test, and two-way repeated measurement ANOVA test (SPSS Version 25.0).

RESULTS

A total of 83 patients were included in this study, with 42 randomized to the remimazolam group and 41 to the midazolam group. There were no significant differences between the two groups in terms of demographic features and operation time. Patients in the remimazolam group had significantly shorter onset time, awakening time, and recovery time compared to those in the midazolam group (each P < .001). Postoperative side effects were more frequent in the midazolam group (P < .001). Following surgery, the Modified Dental Anxiety Scale scores in both groups were significantly lower than prior to surgery (P < .001). Satisfaction levels scores for the patients and doctor were higher in the remimazolam group than in the midazolam group (P < .001).

CONCLUSIONS

The use of remimazolam results in faster onset, more rapid recovery, and lower incidence of postoperative side effects compared to midazolam, leading to improved satisfaction for patients and doctors. Remimazolam therefore appears to have several advantages over midazolam for the sedation of patients with dental anxiety associated with the removal of impacted teeth.

Reliability of two difficulty indexes in predicting the surgical extraction difficulty of impacted mandibular third molars

Introduction: The aim of this study was to compare the reliability and the agreement of the Pederson and Pernambuco difficulty indexes in predicting the surgical extraction difficulty of the impacted mandibular third molars. Materials and methods: A prospective observational cohort study was conducted on 83 patients who had undergone surgical removal of impacted mandibular third molar. The difficulty of extraction was determined preoperatively according to the total scores obtained from the Pederson and Pernambuco difficulty indexes, the operative difficulty was determined by the surgical technique and the duration of extraction. The accuracy of prediction of the surgical difficulty and the degree of agreement of the two indexes were calculated. Results: The accuracy of Pederson and Pernambuco indexes in predicting the operative difficulty measured by duration of surgery was 36.1% and 55.4% respectively, and with operative difficulty measured by the technique was 21.7% and 37.3% respectively with statistically significant differences. The agreement between the 2 indexes was poor. Conclusion: Both indexes were limited in predicting the surgical difficulty of impacted mandibular third molars although the Pernambuco index was better than the Pederson index and the agreement between the two indexes was poor.

A deep learning model based on concatenation approach to predict the time to extract a mandibular third molar tooth

BACKGROUND

Assessing the time required for tooth extraction is the most important factor to consider before surgeries. The purpose of this study was to create a practical predictive model for assessing the time to extract the mandibular third molar tooth using deep learning. The accuracy of the model was evaluated by comparing the extraction time predicted by deep learning with the actual time required for extraction.

METHODS

A total of 724 panoramic X-ray images and clinical data were used for artificial intelligence (AI) prediction of extraction time. Clinical data such as age, sex, maximum mouth opening, body weight, height, the time from the start of incision to the start of suture, and surgeon's experience were recorded. Data augmentation and weight balancing were used to improve learning abilities of AI models. Extraction time predicted by the concatenated AI model was compared with the actual extraction time.

RESULTS

The final combined model (CNN + MLP) model achieved an R value of 0.8315, an R-squared value of 0.6839, a p-value of less than 0.0001, and a mean absolute error (MAE) of 2.95 min with the test dataset.

CONCLUSIONS

Our proposed model for predicting time to extract the mandibular third molar tooth performs well with a high accuracy in clinical practice.

Breakage and displacement of the high-speed hand-piece bur during impacted mandibular third molar extraction: three cases

Background

The high-speed hand-piece bur is one of the methods to perform tooth sectioning during the minimally traumatic extraction of impacted mandibular third molars. During tooth sectioning, the breakage of the bur might take place when it is improperly used. Three cases of the breakage and displacement of a high-speed hand-piece bur during extraction are reported, aiming to remind dental surgeons of this complication.

Case presentation

The bur fragment in case 1 was embedded in the mandibular bone under the previously removed crown of tooth 48 and distal to tooth 47. The bur fragment in case 2 was embedded in the lingual edge of the socket and partly beneath the mucosa on the lingual side. The position of the bur fragment in case 3 was similar to that of case 1 but was completely embedded in the spongious bone. The three cases were performed by first-year residents, and all of the bur fragments were successfully removed by attending doctors after accurately locating them by radiological examination.

Conclusions

In order to avoid breakage of the high-speed hand-piece bur, the number of uses of the bur should be monitored and the integrity and state of the bur should be carefully checked. Moreover, light pressure with little lateral force should be used during tooth sectioning. If bur breakage and displacement occur, the retrieval protocol should be determined based on the imaging findings and conducted as soon as possible to avoid serious consequences.

[Constructions of the scale of difficulty in the extraction of impacted mandibular third molars by using Delphi method]

OBJECTIVE

To evaluate the relevant indicators affecting difficulty in the extraction of impacted mandibular third molars and score difficulty of different operation and risk indicators, so as to build an intuitive and accurate scale to help operators make more accurate analysis and prediction of difficulty before the operation.

METHODS

Based on literature and the clinical review, the difficulty indicators of tooth extraction were summarized. Firstly, 10 doctors from Peking University School and Hospital of Stomatology who had been engaged in alveolar surgery for a long time established an expert nominal group, and then rated whether the summarized indicators needed to be retained in the form of face-to-face questionnaires. A level 1 and 2 item frame for evaluating difficulty in the tooth extraction was formed after discussion; Then Delphi method was used to send a questionnaire to 30 experts by e-mail. After two rounds of scoring and modification, the scale of difficulty in the extraction of impacted mandibular third molars was formed.

RESULTS

The recycling rate of two rounds of questionnaires was 100.0%, which showed that the experts were very enthusiastic about the study; The authority coefficients (Cr) of the two rounds of Delphi expert consultation were both 0.92, which showed that the results were representative and authoritative. After two rounds of grading and revision, the variable coefficient (CV) decreased and the Kendall's concordance coefficient (W) increased, which were statistically significant: In the first round, the CV was 0.24 and W was 0.56 (P < 0.001), and in the second, the CV was 0.19 and W was 0.72 (P < 0.001), which indicated that there was a good convergence among the expert opinions. Finally, a scale of difficulty in the tooth extraction containing 12 items at level A and 37 items at level B was formed, including operation difficulty indicators, risk difficulty indicators and common difficulty indicators.

CONCLUSION

Based on comprehensive literature retrieval, the study has put forward the concept that difficulty in the extraction of impacted mandibular third molars is composed of operation difficulty and risk difficulty. Using Delphi method, the long-term clinical experience and professional knowledge of experts are transformed into quantitative indicators as a scoring scale. The scale has certain representativeness and authority.

The Growth Factors in Advanced Platelet-Rich Fibrin (A-PRF) Reduce Postoperative Complications after Mandibular Third Molar Odontectomy

Surgical removal of impacted mandibular third molars constitutes one of the most frequently performed procedures within oral surgery. This surgery procedure is associated with many post-operative complications. Advanced platelet-rich fibrin (A-PRF) belongs to the second generation of platelet concentrates and is rich in numerous growth factors. The aim of this study was to assess the influence of A-PRF on selected clinical features following the surgical removal of impacted mandibular third molars. The research was conducted on 100 generally healthy patients, who underwent a lower third molar odontectomy in Department of Oral Surgery, Medical University of Gdańsk, Poland, between 2018 and 2019. The research group consisted of 50 patients (immediate A-PRF socket filling) and control group (50 patients without A-PRF socket filling). During the study, the following clinical features were assessed: pain (visual analog scale), analgesics intake, the presence of trismus, edema, hematomas within the surrounding tissues (e.g., cheek), prevalence of pyrexia, dry socket, secondary bleeding, presence of hematomas, skin warmth in the post-operative area, and bleeding time observed by the patient were analyzed on the 3rd, 7th, and 14th day after the procedure. There was a significant association between A-PRF socket filling and pain intensity, the analgesics intake, trismus, and edema on the 3rd and the 7th day (p < 0.05). The presence of hematomas and skin warmth on the 3rd day after the surgery (p < 0.05) were also statistically associated with A-PRF use. The study showed that in reducing the incidence of postoperative complications, A-PRF was more important than the position of the tooth or the duration of the procedure. The growth factors in A-PRF reduce postoperative complications, such as pain, trismus, edema, analgesics intake, presence of hematomas, and skin warmth, after mandibular wisdom teeth odontectomy.

Artificial Intelligence Model to Detect Real Contact Relationship between Mandibular Third Molars and Inferior Alveolar Nerve Based on Panoramic Radiographs

This study aimed to develop a novel detection model for automatically assessing the real contact relationship between mandibular third molars (MM3s) and the inferior alveolar nerve (IAN) based on panoramic radiographs processed with deep learning networks, minimizing pseudo-contact interference and reducing the frequency of cone beam computed tomography (CBCT) use. A deep-learning network approach based on YOLOv4, named as MM3-IANnet, was applied to oral panoramic radiographs for the first time. The relationship between MM3s and the IAN in CBCT was considered the real contact relationship. Accuracy metrics were calculated to evaluate and compare the performance of the MM3-IANnet, dentists and a cooperative approach with dentists and the MM3-IANnet. Our results showed that in comparison with detection by dentists (AP = 76.45%) or the MM3-IANnet (AP = 83.02%), the cooperative dentist-MM3-IANnet approach yielded the highest average precision (AP = 88.06%). In conclusion, the MM3-IANnet detection model is an encouraging artificial intelligence approach that might assist dentists in detecting the real contact relationship between MM3s and IANs based on panoramic radiographs.

Influence of orthodontic treatment with premolar extraction on the spatial position of maxillary third molars in adult patients: a retrospective cohort cone-bean computed tomography study

Background

Based on low-dose radiation Cone-bean computed tomography (CBCT) images, This study aims to establish a space coordinate system, which offers more precise and comparable evaluation on changes of maxillary third molars influenced by orthodontic treatment with premolar extraction in adults. The system suggests promising application prospect in future studies related to CBCT superimposition and evaluation for its feasibility and efficiency.

Methods

Forty-nine maxillary third molars from 27 patients (mean age, 20.78 years) were included. CBCT images were obtained before and after orthodontic treatment with premolars extracted (mean treatment duration, 31.47 months). The changes in the position, angulation, and rotation of the third molars were evaluated with a space coordinate system using four landmarks: anterior nasal spine (ANS), posterior nasal spine (PNS), left and right orbitales.

Results

After orthodontic treatment, the third molars moved forward (adjusted mean, 1.44 mm) (p < 0.001) and downward (adjusted mean, 2.87 mm) (p < 0.001) accompanied by outward rotation of the crowns (adjusted mean, 5.38°) (p = 0.001), while changes in angulation were insignificant.

Conclusions

This was the first study to systematically investigate the spatial position change of maxillary third molars in adult patients who received orthodontic treatment with premolar extraction. During the process, maxillary third molars moved downward and forward accompanied by outward rotation of the crowns. Orthodontists should take tooth movement potential into consideration when making extraction plans.

Establishment and validation of a predictive nomogram for extended operation time following mandibular third molar removal

OBJECTIVES

To develop and evaluate predictive nomogram for extended duration of surgery in patients following mandibular third molars (M3M) removal.

MATERIALS AND METHODS

A retrospectively observational study was performed and designed. A credible random split-sample method was used to divide data into training and validation dataset (split ratio = 0.7:0.3). Least absolute shrinkage and selection operator (Lasso) logistic regression was applied to select predictors and develop the nomogram. The discrimination of the nomogram was assessed using the receiver operating characteristic (ROC) curve, and the calibration curve was used for evaluating the accuracy of prediction. The clinical usefulness of nomogram was also evaluated with decision curve analysis.

RESULTS

Root of curve, Winter classification, Pell-Gregory ramus classification, flap design, procedure, and surgical experience were identified as predictors and assembled into the nomogram. The nomogram showed good discrimination with AUC in training dataset (0.79, 95% CI: 0.73-0.85) and validation dataset (0.75, 95% CI: 0.65-0.84) and was well calibrated in both datasets (all P > 0.05). Decision curve analysis demonstrated that the nomogram was clinically useful.

CONCLUSIONS

This study proposed an effective nomogram with potentially application in facilitating the individualized prediction for extended operation time.

CLINICAL RELEVANCE

Individualized prediction of prolonged operation time can be conveniently facilitating an adequate treatment plan management and postoperative prevention.

Effect of an Informative Video on Anxiety and Hemodynamic Parameters in Patients Requiring Mandibular Third Molar Extraction: A Randomized Clinical Trial

PURPOSE

The purpose was to determine the effect of watching an informative video about mandibular third molar (M3M) removal on patient anxiety and hemodynamic parameters.

PATIENTS AND METHODS

A randomized controlled clinical trial was carried out in healthy patients (aged between 18 and 40 years) requiring M3M extraction under local anesthesia. Patients with previous tooth extractions, psychiatric disorders, or cardiac problems or patients undergoing anxiolytic or antidepressant drug treatment were excluded. Participants were randomized into 2 groups according to whether they watched an informative video about the surgical procedure (video group) or not (control group). The primary outcome variable was the difference between groups regarding patient anxiety assessed with the State-Trait Anxiety Inventory (STAI) and the Modified Dental Anxiety Scale (MDAS). The secondary outcome variables were hemodynamic parameters recorded during different moments of the surgical procedure. Descriptive, bivariate, and multivariate analyses were performed, and a repeated-measures mixed model was generated. Statistical significance was considered for P < .05.

RESULTS

Fifty patients referred for M3M extraction met the inclusion criteria. The final data analysis was based on 47 patients: 25 from the video group and 22 controls. The bivariate analysis showed the video group to have a significant decrease in anxiety as measured by the MDAS (P = .006; 95% confidence interval [CI], -4.1 to -0.7) and STAI-State (P = .003; 95% CI, -13.7 to -0.7). A significantly lower heart rate was likewise found in the video group (χ² = 4.30, df = 1, P = .038). The linear regression analysis adjusting for the STAI-Trait also showed lower dental anxiety measured by the MDAS in the video group (P = .023; 95% CI, 0.32 to 4.14).

CONCLUSIONS

Providing preoperative information through an informative video about M3M removal significantly reduces patient anxiety and heart rate during the surgical procedure.