ong-Term Outcome of Horizontal Root Fractures in Permanent Teeth

Long-Term Outcome of Horizontal Root Fractures in Permanent Teeth: A Retrospective Cohort Study

1. Long-Term Outcome of Horizontal Root Fractures in Permanent Teeth: A Retrospective Cohort Study Guided by: Presented by: Dr. Bobbin Gill Dr. Ritu Khichar

2. Introduction: Horizontal root fracture (HRF) is a complex traumatic dental injury that affects the pulp, dentin, cementum , and periodontal ligament. This fracture usually follows an oblique orientation along the root surface and presents with mobility, dislocation, and tenderness. Emergency treatment involves repositioning the displaced coronal fragment, splinting, and regular follow ups. s

3. . Pulp necrosis is infrequent in the apical fragment but more prevalent in the coronal fragment, occurring in approximately 25% of cases requiring endodontic intervention. Endodontic treatment of the coronal fragment is recommended when the fracture line fails to heal. However, in cases where both coronal and apical pulp tissues are necrotic, treatment becomes challenging.

4. Endodontic treatment through the fracture may adversely affect the periodontal tissues. Surgical removal of the apical fragment is an alternative option if the coronal root fragment provides sufficient support and attachment.

5. Despite existing dental traumatology guidelines, there is a lack of comprehensive literature on managing complicated HRF cases that require endodontic treatment. Hence, the objective of this retrospective study was to assess the long term outcome of teeth with HRF and investigate the prognostic impact of demographic, trauma-related, and treatment related variables on healing at the fracture line.

6. MATERIALS AND METHODS I nclusion criteria for patients were as follows. 1. History of trauma to permanent tooth/teeth leading to sub- crestal HRF, confirmed through clinical and radiographic evaluation. 2. Availability of standard periapical radiographs and clinical information (notes and photographs) for HRF cases from the initial visit to the latest follow-up recall. 3. Minimum follow-up period of 12 weeks.

7. Teeth with incomplete clinical or radiographic records, generalized periodontal problems, supra- crestal HRF, or those concomitant with crown or crown-root fractures were excluded.

8. Data Collection A standardized data collection form was completed in Microsoft Excel 2016 for each patient and included the following information. The demographic information comprised of age, sex, tooth type, and stage of root development. The latter was classified using Cvek’s criteria as follows: 1 (,<1/2 root length), 2 (1/2 root length), 3 (2/3 root length), 4 (wide open apical foramen and nearly complete root length), and 5 (closed apical foramen and complete root development). Stages1-4 were considered incomplete root development.

9. 2. Trauma-related information included the etiology of the injury (traffic accidents, sports activities, falls, fights, or hard object impacts), the location of the fracture line ( apical,middle , or cervical third), concomitant injuries, and the severity of coronal fragment dislocation. Concomitant injuries were classified as mild (concussion or subluxation) or severe (lateral luxation, extrusion, or alveolar fracture).

10. Coronal fragment dislocation was recorded as none( 0.1 mm), slight (0.2-2.0 mm), or marked (>2mm)

11. 3. Treatment-related information included treatment delay, emergency interventions, splinting with or without repositioning of the dislocated coronal fragment (hereafter referred to as splinting/repositioning), the duration of splinting, as well as endodontic treatment (at baseline or follow-up).

12. Outcome Measures and Criteria Radiographic healing of the fracture line was categorized into 4 types (I-IV) based on the classification by Andreasen and Hjorting Hansen. The outcome measure was defined as follows . Favorable outcome: radiographic evidence of healing( typesI -III) at the fracture line,along with the absence of clinical signs or symptoms Unfavorable outcome : radiographic evidence of nonhealing (type IV) at the fracture line and/or the presence of any clinical signs or symptoms that necessitate endodontic intervention or tooth extraction at any point during the patients’ follow-up visits

13. – Radiographic progression of healing in horizontal root fracture cases with different types of healing. This figure showcases preoperative (A ), postoperative (B ), and follow-up radiographs (C ) of 4 teeth with HRF. The type of healing is classified according to Andreasen and Hjorting-Hansen’s19 classification, 1) Case 1 (tooth 1.1): Healing with calcified tissue, fragments in close contact, and minimal or no visible fracture line (type I). 2) Case 2 (tooth 1.1): Healing with interproximal connective tissue, fragments appear separated by a narrow radiolucent line, and fractured edges appear rounded (type II). 3) Case 3 (tooth 2.1): Healing with interproximal bone and connective tissue, fragments separated by a distinct bony bridge (type III). 4) Case 4 (teeth 1.1 and 2.1): Nonhealing with interposition of granulation tissue, evidenced by widened space between fragments or radiolucency adjacent to the fracture line (type IV).

14. RESULTS The study included 103 patients (64.1% male) with a total of 125 teeth . At the time of presentation, the median age of patients was 18.0 . Eighty five patients (82.5%) had one tooth with HRF, 14 patients (13.6%) had two teeth with HRF, and 4 patients (3.9%) had 3 teeth with HRF. The main causes of HRF were sports activities in 27 patients (26.2%), traffic accidents in 24 patients (23.3%), falls in 23 patients (22.3%), fights in 19 patients (18.5%), and hard object impacts in 10 patients (9.7%).

15. Maxillary central incisors were most affected ( n 5 103 teeth, 82.4 %). Fracture lines were primarily located in the middle third (64.8%), followed by the apical third (23.2%) and cervical third (12%). Concomitant injuries were observed, including concussion in 2 teeth (1.6%), subluxation in 37 teeth (29.6%), extrusion in 43 teeth (34.4%), and lateral luxation in 43 teeth (34.4%). Among teeth with lateral luxation, 30.2% ( n 5 13) also exhibited an alveolar fracture.

16. Analysis of Treatment Strategies and Resulting Outcomes The median treatment delay was 3 days (IQR: 1-11 days ). Specifically, 30 teeth in 28 patients (24% of study teeth) received dental treatment within 24 hours, while 54 teeth in 42 patients (43.2% of study teeth) received dental treatment within 2-7 days. The remaining cases (41 teeth in 33 patients, 32.8% of the study teeth) received dental treatment after 1 week.

17. All study teeth necessitated emergency splinting with a semi-rigid splint. Notably, 60.8% were splinted for >12 weeks, often due to patient noncompliance or excessive tooth mobility after initial splint removal . Eighty-six out of 125 teeth (69%) also underwent digital repositioning of dislocated coronal fragments.

18. The following treatment approaches were guided by initial assessments of coronal fragment dislocation and pulpal status . 1. At baseline, 98 teeth received emergency interventions of splinting/repositioning but did not require endodontic treatment. Of these, 61 teeth (62.2%) had favorable outcomes with clinical normalcy and evidence of radiographic healing (20.4% type I, 28.6% type II, and 13.2% type III).

19. In total, 64 teeth necessitated endodontic treatment. These teeth underwent pulpectomy in the coronal fragment,followed by 2–24 weeks of calcium hydroxide medication. The coronal fragments of 57 teeth were obturated with mineral trioxide aggregate (MTA), while gutta-percha and resin-based sealer were used in 7 teeth with fracture lines at the apical third of the root. Composite resin was employed for the final restoration.

20. Among these 64 teeth, 27 teeth received endodontic treatment at baseline, in conjunction with splinting/repositioning. The reasons included complete pulp tissue loss in both the apical and coronal fragments (due to a significantly dislocated coronal fragment in 4 teeth, and misdiagnosis in 6 teeth, leading to a full pulpectomy performed by the referring dentist) or evidence of coronal pulpal necrosis associated with a significant delay in seeking treatment.

21. For the remaining 37 teeth, nonhealing at the fracture line was observed after baseline splinting/repositioning, necessitating endodontic treatment during follow-up appointments. The median time to endodontic treatment for these teeth was 10.5 weeks . Of the 64 teeth, 61 met the minimum 12-week follow-up criteria. Among them, 88.5% (54 teeth) showed favorable outcomes, categorized as 13.1% type I, 23% type II, and 52.4% type III.

22. After a median follow-up of 79.0 weeks , 92% of the overall sample (125 study teeth) had favorable outcomes. The rate of favorable outcomes was 86.7% at 4 weeks (52 of 60 available teeth), 75.0% at 5- 8 weeks (42 of 56 available teeth), 84.9% at 9- 12 weeks (45 of 53 available teeth), 88.8% at 13-24 weeks (71 of 80 available teeth), 83.9% at 25-52 weeks (52 of 62 available teeth), and 94.4% at .52 weeks (67 of 71 available teeth). Except for 5 teeth that were extracted after a median follow-up of 32.0 weeks , a high survival rate of 96% was observed.

23. Analysis of Prognostic Factors In initial univariate analyses, age, sex, and root development stage showed significant associations with baseline splinting/ repositioning and the need for endodontic treatment (either at baseline or follow-up appointments ). Treatment delays influenced the need for endodontic treatment.concomitant luxation injuries, severity of coronal fragment displacement, and location of the fracture line did not significantly affect the outcome of emergency treatment or the need for endodontic treatment.

24. The final analyses revealed the following prognostic variables . Being male, compared to female, was significantly associated with a better outcome of emergency intervention and a lower likelihood of requiring endodontic treatment . Incomplete root development, in comparison to complete root development, significantly reduced the likelihood of needing endodontic treatment and resulted in a more favorable outcome in baseline intervention .

25. Treatment delays surpassing one week, compared to timely presentations within 24 hours, were significantly associated with an increased likelihood of requiring endodontic treatment .

26. After a median follow up of 79.0 weeks, we observed a remarkable 96% retention rate for study teeth with HRF. This surpasses previously reported rates ranging from 80%24 to 91%26. Furthermore, 92% of the study teeth exhibited a favorable outcome, as evidenced by radiographic healing at the fracture line and the absence of clinical signs or symptoms.

27. Prior studies primarily focused on assessing the healing rate at the fracture line following splinting/repositioning, without considering endodontic intervention. Reported healing rates vary from 45% to 78% in these studies. Our healing rate of 62% in teeth that solely received emergency interventions of splinting/repositioning at baseline falls within this range. Specifically, our results align with rates reported by Majorana et al. and Caliskan et al. (60% to 62.5%), but exceed the 45% presented by Welbury et al. ’s due to their inclusion of borderline cases with both HRF and crown fractures.

28. Contrastingly,our rate is lower than the 77–78% reported by Andreasen et al. and Cvek et al. possibly due to their inclusion of younger participants with treatment delays of ≤5 days.

29. We observed a more favorable outcome with emergency interventions among males, resulting in a reduced need for endodontic treatment. In our study, distinct clusters of males with potentially better risk indicators were identified. males in our study comprised a higher proportion of patients below 18 years of age, experienced shorter treatment delays, and had HRF cases with no or slight coronal fragment displacement or incomplete root development These findings suggest that the males in our study exhibited characteristics associated with a potentially better outcome.

30. Research suggests that teeth with incomplete root development have a lower likelihood of HRF compared to those with complete development. This is likely due to the heightened elasticity of the tooth’s socket in immature teeth, potentially reducing HRF. Our results also align with prior studies, indicating more favorable outcomes in immature teeth with HRF. This is likely due to factors such as a larger volume of pulp tissue, greater availability of inflamatory mediators , proximity to the main vascular supply , and a higher density of the vasculature system.

31. Our study revealed a significant association between treatment delays exceeding one week and the subsequent need for endodontic intervention . Patient delays in seeking dental treatment may stem from a lack of awareness of dental trauma management. Additionally, the severity of coronal fragment dislocation influences the speed at which patients seek dental care. a promising 73% of cases with late referrals still had a reasonable chance of achieving a favorable outcome at the fracture line.

32. Our study suggests the potential for healing even in complicated cases. Therefore, a preservation approach should be prioritized, especially for individuals in the critical period of alveolar growth . To emphasize this point, we examined 2 subgroups of complicated HRF cases from our database .

33. 1.The complete loss of pulp tissue in both coronal and apical fragments may arise from the complete extrusion of apical pulp tissue often attached to severely dislocated coronal fragments or inadvertent pulpectomy in symptomatic teeth where HRF was undetected . In such cases, attempting to obturate both coronal and apical fragments poses the risk of material extrusion and potential failure

34. Conversely , surgical removal of the apical fragment compromises tooth support. Our study employed a conservative approach for 10 such teeth, involving intra-canal medication with calcium hydroxide followed by MTA obturation of the coronal fragment and permanent restoration. After a median follow-up of 248.5 weeks , these cases showed successful healing . This suggests that a pulpless apical fragment, when properly sealed against bacterial invasion at the fracture line, does not hinder the healing process.

35. 2. Excessive tooth mobility upon removing baseline splinting increases the risk of tooth loss, particularly when HRF is located in the cervical third of the root. Notably, 70% of such cases may necessitate extraction. This risk is linked to the healing type, with connective tissue healing (types II or III) diminishing the coronal fragment’s ability to withstand forces Conversely, when teeth with HRF undergo healing with calcified tissue (type I), tooth loss is not dependent on the fracture’s location. This group shows normal mobility after splint removal. In 30 teeth with HRF in the middle or cervical third, we observed excessive mobility after removing baseline splinting. To improve survival, permanent splinting with orthodontic retainers was applied.

36. After a median follow-up of 139.5 weeks (IQR: 39.0-277.5; range: 32 to 629), 27 teeth showed type II healing at the fracture line. However, the remaining three, initially displaying type II healing, eventually exhibited a nonhealing type IV pattern and developed deep periodontal pockets. Emphasizing excellent oral hygiene in these cases is crucial for preserving periodontal health and increasing the chance of tooth survival.

37. limitations 1. The retrospective nature of the chart review design introduces potential issues such as irregular follow-ups, missing data, selection bias, and confounding due to nonrandomization . 2. In this study, the majority of patients did not undergo cone beam computed tomography (CBCT) at baseline. 3. The median follow-up duration in this research was 79 weeks. Nevertheless, longer follow-ups can offer a more comprehensive understanding of healing processes in teeth with HRF .

38. CONCLUSION Our investigation indicates generally favorable outcomes for permanent teeth with HRF. Male sex and incomplete root development were associated with improved baseline outcomes and a reduced likelihood of needing endodontic treatment. Conversely, delayed presentation increased the need for endodontic intervention. These results underscore the importance of timely diagnosis, personalized interventions, and close monitoring for optimizing outcomes of teeth with HRF.

39. METHODS A retrospective clinical study was performed between 2009 and 2016 in the Department of Dentistry at the University of Messina. The analysis included 42 patients (27 males, 15 females), with a mean age of 28.24 years, presenting a middle third horizontal root fracture in permanent dentition due to traffic accident, classified by WHO as A (Injuries to the hard dental tissues and the pulp) #.7 (Root Fracture - N 502.53 - fracture involving dentin, cementum , and the pulp.) [29]. For each patient a medical history was collected and a clinical examination through inspection.

40. palpation and percussion, vitality tests and a radiological evaluation ( periapical x-ray), was performed (t). The parameters recorded were: diastasis, mobility, sensibility, periodontal inflammation, pulpal pathology and the presence of associated fracture and dislocation of the coronal fragment. (Fig. 1) The treatment plan was decided depending on the single clinical situation, performing the repositioning of the coronal fragment, with a semi-rigid splint of composite resin to the adjacent teeth and the root canal treatment in case of pulpal involvement. (Fig. 2) The follow-up was performed at 6 (t1 ), 12 (t2 ) and 36 (t3 ) months after the trauma, both clinically and radiologically . (V. Figs. 3, 4) Statistical analysis was performed as follows.

41. The age was the only numerical variable and it was expressed as mean, standard deviation, median, minimum and maximum; the categorical variables were expressed as numbers and percentages. The non-parametric approach was used because of the low sample size. The Cochran test was applied in order to evaluate the existence of significant differences for the presence of diastasis, inflammation, mobility, sensitivity and pulpal lesions in four different times (basal, 6, 12 and 36 months). The Mc Nemar test was estimated to perform statistical comparison between two consecutive times for each parameter. In order to evaluate the association between sex, fracture, dislocation, repositioning and splint with presence/absence of diastasis, inflammation, mobility, sensitivity and pulpal lesions (for each time), the Pearson’s P square was applied; alternatively, the exact Fisher test was estimated, when a frequency in the contingency table was less than 5. P

42. CONLCUSION The analysis of the clinical results exhibits the high success rate of a conservative approach in the treatment of teeth fractured in the middle third of the root. Just in one case extraction of the involved teeth was necessary after 36 months. In 50% of cases endodontic treatment was immediately performed due to a pulp exposure caused by the fracture itself. In a low percentage of cases a late root canal treatment was performed because of pulpal and periapical complications. A careful monitoring of all the clinical parameters involved especially mobility, diastasis and pulp status is confirmed to be crucial for a correct and conservative approach. The immediate treatment of the intra alveolar root fracture with the severely displaced coronal fragment was important for the good prognosis, aesthetical results, and long term success