Full life cycle changes of low impacted mandibular third molar associated cystic lesions and adjacent tooth root resorption: a retrospective study.

OBJECTIVE: Low impacted third molars are usually asymptomatic and are often found by X-ray examination. The removal of asymptomatic low impacted third molars is one of the most controversial clinical issues in oral and maxillofacial surgery. METHODS: In this study, 806 patients with low impacted mandibular third molars (LIMTMs) (full bony impaction) were analyzed to determine the prevalence and risk factors for cystic lesions and adjacent tooth root resorption throughout the patients' entire life cycle. RESULTS: The results showed that the prevalence of adjacent tooth root resorption and cystic lesions was age-related, exhibiting a trend of first increasing and then decreasing; prevalence peaked at the age of 41 to 45 years old, the prevalence rates were 12.50% and 11.11% respectively. And the lowest prevalence rate was 2.86% and 2.44% in ≥ 61 group and 56- to 60-year age group respectively. Age was an independent risk factor for adjacent tooth root resorption of LIMTMs, whereas age and impaction type (especially inverted impaction) were independent risk factors for cystic lesions. CONCLUSIONS: The full life cycle management strategy for LIMTMs may need to be individualized. Surgical removal is recommended for LIMTMs in patients younger than 41 to 45 years, especially for inverted, mesioangular, and horizontally impacted LIMTMs. LIMTMs in patients older than 41 to 45 years may be treated conservatively with regular follow-up, but surgical removal of inverted impacted LIMTMs is still recommended to avoid cyst formation.

Long-term follow-up after the treatment of impacted canines in the maxilla causing severe root resorption of the lateral incisors: two case reports.

BACKGROUND: Root resorption of adjacent teeth due to impacted canines is common, and orthodontic treatment often leads to secondary resorption or even loss of adjacent roots. Clinical reports of long-term stability after treatment are rare. CASE PRESENTATION: This study reports two cases of maxillary impacted canines resulting in severe root resorption of the adjacent lateral incisors. Surgical exposure, orthodontic retraction, and alignment of the impacted canines were successful in both cases, and the resorbed lateral incisors were stable with no significant loosening and normal pulp vitality after treatment and at the 5- and 10-year follow-up appointments. CONCLUSIONS: Light orthodontic force may be used to move adjacent teeth with root resorption due to tooth obstruction. The path and direction in which the teeth are moved must be specifically designed so that the adjacent roots are not resorbed and so long-term stability can be achieved.

Influence of alveolar bone thickness and bucco-palatal inclination on root resorption of lateral incisors in unilateral maxillary impacted canines: a retrospective observational study.

BACKGROUND: This study aimed to investigate the potential associations between alveolar bone thickness, bucco-palatal inclination of maxillary lateral incisors, and lateral incisor root resorption in patients with unilateral maxillary impacted canines (UMICs). METHODS: A total of three hundred and five subjects (120 males, 185 females; mean age, 16.39 years; standard deviation, 4.04) with UMICs were included. Canine position and root resorption were assessed using CBCT. UMICs were divided into palatal, buccal and mid-alveolus groups (PICs, BICs and MAICs), with 117, 137 and 51 subjects, respectively. Alveolar bone thickness and bucco-palatal inclination of lateral incisors were measured using the Dolphin software. RESULTS: The prevalence of lateral incisor root resorption was significantly lower in the BICs (13.9%) than MAICs (29.4%) and PICs (29.1%). Alveolar bone thickness of the apical area was smaller in UMICs with lateral incisor root resorption than no resorption in both PICs (8.33 ± 1.64 vs 10.53 ± 2.55 mm) and BICs (8.94 ± 1.85 vs 10.76 ± 2.28 mm). Furthermore, lateral incisors on the impacted side were more buccally inclined in PICs with lateral incisor root resorption than no resorption, while in both BICs and MAICs, there was no statistical difference between lateral incisor root resorption than no resorption. Moreover, alveolar bone thickness of the apical area, rather than bucco-palatal inclination of lateral incisors, was significantly correlated with lateral incisor root resorption both in PICs and BICs. CONCLUSIONS: Lateral incisor root resorption is less common in BICs. Thinner alveolar bone thickness at the apical area of lateral incisors can be considered as a potential risk factor for lateral incisor root resorption in UMICs.

Prevalence of impacted third molars: a radiographic study among a North African population.

INTRODUCTION: Third molars are the most commonly concerned teeth with the impaction. Impacted third molar (ITM) can be associated to various clinical pathologies Aim: To determine the prevalence of ITM, its pattern and associated affections in Tunisian patients. METHODS: The study reviewed panoramic radiographs of patients consulting the Fattouma Bourguiba University Hospital, Monastir (Tunisia). Orthopantomograms were analyzed to define the prevalence of ITM; its angulation, depth and relation with the anterior border of mandibular ramus. Associated pathologies were also assessed. RESULTS: Seven hundred and thirty patients were included (286 men and 444 women). The age ranged from 19 to 89 years. Half of the patients (50.3%) showed at least one ITM. The total number of ITM was 881 with a statistical difference between arches (respectively 34.3% and 65.7% in the maxilla and in the mandible). The most common number of ITM was two (35.4%). Level C of impaction was observed more frequently in the maxilla and level A in the mandible. The most common angulation was the vertical one for both arches. Seventy six percent of ITM were presented with class II in relation with the anterior border of mandibular ramus. There was no significant difference in the frequency of impaction between gender and sides. The number of ITM associated with pathological conditions was 199 (22.6%). The most frequently observed pathology was the distal caries on the second molars (11.7%) followed by the caries of the third molars (5.2%). CONCLUSION: The prevalence of ITM among Tunisian patients was high.

Outcomes of Coronectomy and Total Odontectomy of Impacted Mandibular Third Molars.

OBJECTIVE: The aim of this research was to evaluate the surgical complications and neurosensory deficits after coronectomy and the complete removal of mandibular third molars. METHODS: The study sample included patients requiring surgical removal of mandibular third molars. A coronectomy was conducted on 220 teeth showing signs of close proximity to the inferior alveolar canal. A complete extraction was performed on 218 teeth with no risk signs. The patients were evaluated at 1 week and 1, 3, 6, 12, and 24 months after surgery for pain, swelling, neurologic deficit, dry socket, postoperative bleeding, infection, root migration, and eruption. RESULTS: No significant difference was noted in pain and swelling; however, bleeding and dry socket were significantly higher in the odontectomy group (P = .017). The inferior alveolar nerve deficit was higher in the odontectomy group (3.7%) than the coronectomy group (0.5%) (P = .017). The percentage and distance of root migration of coronectomised teeth at 3, 6, and 12 months were 60% (2.37 ± 0.96 mm), 66% (3.35 ± 0.86 mm), and 74% (3.85 ± 0.93 mm), respectively. CONCLUSIONS: Coronectomy is a safe procedure and should be performed when the roots are closely associated with the mandibular canal. Although root migration is common, the likelihood of root exposure is low and roots rarely need removal.

Factors Associated With Successful Surgical Exposure of Impacted Maxillary Canines.

PURPOSE: Impacted maxillary canines occur in up to 3% of the population and their eruption is of great importance in establishing, maintaining the shape, aesthetics, and function of the dental arch. Hence, surgical exposure of canines for the purpose of aligning them is a common surgical procedure. This study identifies the frequency and the statistically significant factors associated with successful surgical exposure of impacted maxillary canines and the relative risk factors for repeat surgery. METHODS: This is a retrospective cohort study of 182 patients who underwent surgical exposure of impacted maxillary canines and orthodontic alignment, over a 5-year period between 2014 and 2018. The variables recorded and analyzed included demographics (age and gender), type of surgery (closed or open exposure), grade of surgeon, and radiographic features on orthopantomogram (canine overlap of adjacent tooth root, vertical canine crown height, canine angulation to midline, position of canine root apex). Outcome data recorded were successful surgical exposure and orthodontic alignment and the need for repeat operation or surgical removal due to ankylosis. The data were analyzed to identify the statistically significant correlates of successful surgical exposure and the relative risk factors associated with repeat surgery. RESULTS: A total of 182 patients and 232 bone-impacted maxillary surgical canine exposures were analyzed, as 50 patients had bilateral impaction. Mean age was 15 years (range = 10-38 years), with 122 (67%) female to 60 (33%) male ratio. Total of 222/232 (96%) impacted maxillary canine teeth were successfully surgically exposed and 10/232 (4%) required re-exposure surgery. Correlates of successful surgical exposures were open exposure technique (P < .002) and reduced distance of vertical canine crown height from alveolar bone margin (P < .033). Relative risk factors for repeat surgery were increased age, male, closed surgical exposure, grade of surgeon, central impaction, increased overlap of adjacent root, increased vertical height, increased angulation to midline, canine apex position above second premolar and procedure done under local anesthetics. CONCLUSIONS: This is the largest impacted maxillary canine study to date which has identified the factors that result in successful surgical exposure, hence allow selection of the patients most suitable for this treatment. Secondly, patients with relative risk factors for repeat surgical intervention may be consented appropriately, triaged for a closer orthodontic follow-up and prioritized for surgery to reduce overall treatment time.

The relationship of the position of mandibular third molar impaction with the development of dental and periodontal lesions in adjacent second molars.

OBJECTIVE: The aim of this study was to evaluate the effect of different positions of Mandibular third molar impaction teeth on dental and periodontal lesions of mandibular second molars and correlate the lesion severity with patient age. MATERIALS AND METHODS: This retrospective study assessed 212 CBCT images of patients who visited the department of Oral and Maxillofacial radiology of XX university between 2017 and 2021. Periodontal and dental lesion effects of impacted third molars on mandibular second molars were evaluated. While dental lesions were classified as mild, moderate, and severe, periodontal lesions were classified as mild in cases not exceeding 2/3 of the root, and severe in cases exceeding 2/3 of the root. Pearson's chi-square tests, Mann-Whitney U or Kruskal-Wallis test were used for data analsis. A multivariate logistic regression model was constructed for further analysis. RESULTS: Periodontal lesions were frequently observed in the second molar adjacent to the third molar (157 teeth, 74.1%), dental lesions were observed in 10%. Among the third molar positions, the mesioangular position was associated with a high (88%) prevalence of periodontal lesions (p<0.001), followed by the horizontal position (71%). The periodontal lesion was more severe in cases 30-39 years old and over 40 years old than in cases under 20 years old and 21-24 years old. Distoangular, horizontal and vertical/inverse positions are less likely to increase the severity of the periodontal lesion than the mesioangular position. (OR = 0.02; p <0.001, OR = 0.28; p =0.008, OR = 0.14; p <0.001,respectively). CONCLUSIONS: The third molars are often impacted in the mesioangular position, and this position most increases the risk of periodontal infection in the second molars. Accurate diagnosis and evaluation can minimize complications, and CBCT is a reliable imaging technique in which the position of the third molars and their relationship with the 2nd molars can be evaluated.

Is it possible to predict neurosensory alterations in impacted lower third molar removal based on preoperative imaging procedures? A prospective cohort study.

BACKGROUND: Surgical extraction of the lower third molar (LTM) may trigger neurosensory injury of the inferior alveolar nerve, making extraction a real challenge. This study set out to assess whether is it possible to predict neurosensory alterations from preoperative imaging. MATERIAL AND METHODS: A total of 99 patients underwent 124 impacted lower third molar (ILTM) surgeries. Prior to surgery, panoramic and CBCT images were evaluated in an attempt to predict a neurosensory disturbance. Preoperative data (ILTM position, panoramic radiograph signs, inferior alveolar nerve (IAN) location and its contact with the ILTM roots) and intra/postoperative findings (extraction difficulty and sensitivity alterations) were recorded. Descriptive and bivariate data analysis was performed. Statistical comparison applied the chi-square test, Fisher test, and one-way ANOVA test. Statistical significance was established with a confidence interval (CI) of 95%. RESULTS: In 4.03% of cases, patients experienced neurosensory alterations. Of 124 ILTM positions in panoramic radiographs, 76 cases were considered to exhibit a potential neurosensory risk as they presented two or more types of superimposed relationships between ILTM and mandibular canal. Of these, alterations were reported in only three cases (3.95%). Of the 48 remaining ILTM images presenting only one sign, neurosensory alterations were observed in two cases (4.17%). No permanent alterations were recorded in any of the five cases observed. CONCLUSIONS: Within the limitations of the present study, prediction of neurosensory alterations prior to ILTM extraction by means of preoperative imaging did not show a significant statistical correlation with post-surgical incidence. Nevertheless, interruption of the canal´s white line (ICWL) or a diversion of the canal (DC) may predict an increased risk of IAN injury.