Risk factors associated with the occurrence of avulsion in the primary incisors: A case-control study.

BACKGROUND: Identifying factors associated with the occurrence of primary tooth avulsion is essential to promote prevention strategies. AIM: To investigate the risk factors associated with primary incisor avulsion and variables associated with post-avulsion sequelae in the permanent successor. DESIGN: This case-control study comprised 407 children (cases) with primary incisor avulsion and 407 children (controls) with other traumatic dental injuries (TDI). The association between explanatory variables and avulsion was evaluated through logistic regression. Odds ratios (OR) and 95% confidence intervals (95% CI) were calculated. Poisson regression analyses between potential explanatory variables and sequelae were run, from which relative risks (RR) and corresponding 95% CI were estimated. RESULTS: TDI caused by moderate falls (OR = 2.20; 95% CI = 1.47 to 3.27), affecting lateral incisors (OR = 10.10; 95% CI = 3.89 to 26.54) and the lower arch (OR = 9.54; 95% CI = 3.15 to 28.85), were associated with primary incisor avulsion. Moreover, children with previous severe TDI, anterior open bite, and anterior crossbite had higher odds of primary incisor avulsion. Children who suffered from any primary tooth avulsion (RR = 2.68; 95% CI = 1.82 to 3.95) had a higher risk of sequelae in the permanent successors. The risk for sequelae in the permanent teeth was significantly greater for younger children under age 2 years than for children ages 3 to 5 years. CONCLUSION: Risk factors for primary incisor avulsion are related to the severity of the fall, tooth position, history of previous TDI, and malocclusion. Furthermore, avulsion increases the risk of sequelae in the permanent successors.

A pilot study comparing optical coherence tomography, radiography, clinical photography, and polarisation microscopy for studies of hypomineralisation disturbances in enamel.

Aim: To investigate the use of optical coherence tomography (OCT) as a tool to assess general and localised hypomineralisation defects in the enamel. Design and Materials: Ten extracted permanent teeth (four teeth with localised hypomineralisation, four teeth with general hypomineralisation, and two healthy controls) were used in this study. In addition, four participants who underwent OCT served as living controls for the extracted teeth. Methods: The OCT results were compared with clinical photographs, digital radiographs, and polarising microscopy images of tooth sections (considered the gold standard) to determine the method with the most accurate information regarding the extent of enamel disturbances: 1) visibility of enamel disturbance (visible yes/no); if yes, 2) extent of the disturbance in the enamel; and 3) determination of the plausible involvement of the underlying dentin. Results: OCT was more accurate than digital radiography and visual assessment. OCT could provide information about the extent of localised hypomineralised disturbances in the enamel that was comparable to that with polarisation microscopy of the tooth sections. Conclusion: Within the limitations of this pilot study, it can be concluded that OCT is suitable for investigating and evaluating localised hypomineralisation disturbances; however, it is less useful in cases with generalised hypomineralisation of the enamel. In addition, OCT complements radiographic examination of enamel; however, more studies are necessary to elucidate the full extent of the use of OCT in case of hypomineralisation.

Impact of avulsion of the primary incisors on the occurrence of sequelae in the permanent teeth: A retrospective cohort study.

OBJECTIVES: The purpose of this retrospective cohort study was to investigate the occurrence of sequelae in the permanent teeth after avulsion of their primary antecessors and to evaluate the factors associated with this occurrence. METHODS: We screened 2922 records of patients with photographic and radiographic images who attended a reference centre for dental trauma in the primary teeth from 1998 to 2019. Among them, 240 were eligible records of children who had suffered avulsion of the primary incisors and were followed up until complete eruption of the permanent successors. Multilevel Poisson regression analyses were conducted between the explanatory variables related to children and avulsed teeth; outcome variables were occurrences of any type of sequelae in the permanent teeth, opacities, hypoplasia and malformation. Relative risks (RRs) and respective 95% confidence intervals (95% CIs) were calculated. RESULTS: Among the 240 children's records, 194 fulfilled the inclusion criteria. Finally, we found 266 primary avulsed teeth and 115 (43.2%) permanent teeth presenting with sequelae. Avulsion occurring when children were older than 4 years (RR = 0.48; 95% CI = 0.24-0.95) had lower risks for developing sequelae than children aged 0-2 years of age. Additionally, when avulsion occurred in the lower dental arch (RR = 1.45; 95% CI = 1.06-1.99) and when three or more teeth were affected (RR = 1.57; 95% CI = 1.02-2.41), the occurrence of sequelae in the permanent teeth was more probable than if avulsion occurred in the upper arch and affected only a single tooth. Age older than 3 years was a protective factor for the occurrence of hypoplasia and age older than 4 years protective for the occurrence of opacities. CONCLUSIONS: The risk of sequelae in the permanent teeth after avulsion of their antecessor is higher when the trauma occurs in young children (<2 years) and in patients with avulsions of greater magnitude, such as when it affects the lower jaw, and more teeth are involved.

Treatment Strategies for Patients with Regional Odontodysplasia: A Presentation of Seven New Cases and a Review of the Literature.

PURPOSE: Regional odontodysplasia (RO) is a rare dental anomaly affecting primary and/or permanent dentition, and leads to comprehensive treatment need. The purpose of this study was to present a larger consecutive sample with RO, discuss treatment strategies for patients with RO, and review the literature. MATERIALS AND METHODS: A consecutive, retrospective sample of seven children with RO (6 males, 1 female) including all patients diagnosed with RO in the eastern part of Denmark was conducted over a period of 15 years. The evaluation included gender, localisation and treatment outcome. A review of the literature and cases published within the last 15 years was conducted. RESULT: Referral age was 2-12 years (mean: 7.3 years). The gender ratio was 1:6 (female:male), and the right:left ratio was 3:4. 71% of the patients had RO in the mandible and 29% in the maxilla. 43% had RO in the permanent dentition, while both primary and permanent dentition were affected in 57%. Typically, RO affected incisors and canines. In some patients, RO also affected more distal tooth types. Treatment included early multiple extractions and subsequent combined orthodontics, surgery and prosthetics. A search on RO cases published within the last 15 years was conducted and included 44 cases. The review showed a male and maxillary preponderance. The most common treatment of RO is extraction. CONCLUSION: Treatment of RO should take place in interdisciplinary, specialised teams, and individual treatment plans should be designed. Fewer but more extensive treatment sessions under general anesthaesia may minimise the burden of care for the patients.

Periodontal healing complications following extrusive and lateral luxation in the permanent dentition: a longitudinal cohort study.

PURPOSE: To analyze the risk of tooth loss and complications in periodontal ligament (PDL) healing following extrusive and lateral luxation in the permanent dentition. MATERIALS AND METHODS: Eighty-two permanent teeth (78 patients) with extrusive luxation and 179 teeth (149 patients) with lateral luxation were included in the study. All teeth were examined according to a standardized protocol including clinical, photographic, and radiographic registration. Follow-up controls were performed at regular intervals (3, 6 weeks, 6 months, 1, 5, and 10 years). STATISTICS: The risk of repair-related resorption (surface resorption), infection-related resorption (inflammatory resorption), ankylosis-related resorption (replacement resorption), marginal bone loss, and tooth loss was analyzed with the Kaplan-Meier method. Differences among subgroups were analyzed with log-rank test and Cox regression. RESULTS: The risk of periodontal healing complications was estimated after 3 years. Extrusive luxation: For immature root development, infection-related resorption was 2.4% (95% confidence interval (CI): 0-6.9%). For mature root development, repair-related resorption was 15.6% (95% CI: 4.4-26.7%), infection-related resorption was 5.1% (95% CI: 0-11.7%), and marginal bone loss was 17.5% (95% CI: 6.2-28.8%). No teeth showed ankylosis-related resorption, and no teeth were lost in the observation period. Lateral luxation: For immature root development, repair-related resorption was 2.1% (95% CI: 0-6.1%), infection-related resorption was 2.1% (95% CI: 0-6.1%). For mature root development, repair-related resorption was 29.5% (95% CI: 20.5-38.5%), infection-related resorption was 2.6% (95% CI: 0-6.4%), ankylosis-related resorption was 0.8% (95% CI: 0-2.3%), marginal bone loss was 6.9% (95% CI: 2.2-11.6%). CONCLUSION: The risk of severe periodontal healing complications in teeth with extrusive and lateral luxation injuries is generally low. Marginal bone loss and repair-related resorption occurred significantly more often in teeth with mature rather than immature root development. Marginal bone loss was associated with injuries involving multiple teeth.

Pattern of traumatic dental injuries in the permanent dentition among children, adolescents, and adults.

BACKGROUND: Traumatic dental injuries (TDI) comprise six types of luxation and seven types of tooth fractures. The risk of pulp necrosis is increased in teeth with combination injuries where fractures and luxations occur concomitantly. AIM: To report and compare the distributions of luxations and fracture types among children, adolescents, and adults, and to analyze the distribution and prevalence of combination injuries. MATERIAL AND METHOD: The study group included 4754 patients (3186 men and 1568 women) with 10 166 traumatized permanent incisors treated at Copenhagen University Hospital, Rigshospitalet. Differences in the distributions of trauma types among age groups (children <12 years, adolescents 12-20 years, and adults >20 years) and distributions of concomitant crown fractures for each luxation type were analyzed with the Chi-square test. RESULTS: A total of 7464 teeth (73.4%) had suffered a luxation injury and 5914 teeth (58.2%) a fracture. The overall most frequent injuries were crown fractures without pulp exposure (34.9%), concussions (24.2%), and subluxations (22.2%). The relative frequency of crown fractures without pulp exposure decreased across age groups (children 45.2%, adolescents 36.5%, adults 26.3%, P < 0.001), whereas the relative frequencies of other injury types increased across age groups : crown-root fractures (children 1.8%, adolescents 6.3%, adults 9.2%, P < 0.001), root fractures (children 2.5%, adolescents 4.6%, adults 8.7%, P < 0.001), and lateral luxations (children 5.7%, adolescents 10.9%, adults 13.0%, P < 0.001). One-third of the traumatized teeth (n = 3212) had sustained a combination of a fracture and a luxation injury. The luxation types most frequently presenting with a concomitant crown fracture were concussion (57.9%), intrusion (47.2%), and subluxation (33.4%) (P < 0.001). CONCLUSION: The majority of TDI were minor injuries. The relative frequencies of injury types varied among age groups. Combination injuries were observed in one-third of the traumatized teeth and occurred most frequently in teeth with concussion, intrusion, and subluxation.

Periodontal healing complications following concussion and subluxation injuries in the permanent dentition: a longitudinal cohort study.

PURPOSE: The purpose of the study was to analyze the risk of periodontal ligament (PDL) healing complications following concussion and subluxation injuries in the permanent dentition. MATERIAL AND METHOD: A total 469 permanent teeth (358 patients) with concussion and 404 permanent teeth with subluxation were included in the study. All teeth were examined according to a standardized protocol including clinical, photographic, and radiographic registration. STATISTICS: The risk of repair-related resorption (surface resorption), infection-related resorption (inflammatory resorption), replacement-related resorption (ankylosis), marginal bone loss, and tooth loss were analyzed with the Kaplan-Meier method. RESULTS: Concussion: In teeth with immature root development, no healing complications were observed. For teeth with mature root development, the risk of repair related resorption after 3 years was 3.2% (95% CI: 0.3-6.0%) and occurred only in cases where several teeth were injured simultaneously (multiple-trauma cases). The risk of marginal bone loss in teeth with mature root development was 0.7% (95% CI: 0-1.6%). Infection-related resorption, replacement resorption, and tooth loss were not observed among teeth with concussion. Subluxation: In teeth with immature root development, the risk of infection-related resorption after 3 years was 1.7% [95% confidence interval (CI): 0-3.8%]. Infection-related resorption occurred significantly more often in teeth with concomitant crown fracture (P = 0.004). For teeth with mature root development, the risk of periodontal healing complications after 3 years was: repair-related resorption, 3.6% (95% CI: 0-7.6%); infection-related resorption, 0.6% (95% CI: 0-1.7%); replacement-related resorption, 0.6% (95% CI: 0-1.7%); and marginal bone loss, 0.6% (95% CI: 0-1.7%). No teeth were lost in the observation period. CONCLUSION: The risk of periodontal healing complications after concussion as well as subluxation injuries in permanent teeth is very low.

Combination injuries 2. The risk of pulp necrosis in permanent teeth with subluxation injuries and concomitant crown fractures.

BACKGROUND: The reported risk of pulp necrosis (PN) is generally low in teeth with subluxation injuries. A concomitant crown fracture may increase the risk of PN in such teeth. AIM: To analyse the influence of a concomitant trauma-related infraction, enamel-, enamel-dentin- or enamel-dentin-pulp fracture on the risk of PN in permanent teeth with subluxation injury. MATERIAL AND METHODS: The study included 404 permanent incisors with subluxation injury from 289 patients (188 male, 101 female). Of these teeth, 137 had also suffered a concomitant crown fracture. All the teeth were examined and treated according to a standardized protocol. STATISTICAL ANALYSIS: The risk of PN was analysed separately for teeth with immature and mature root development by the Kaplan-Meier method, the log-rank test and Cox regression analysis. The level of significance was set at 5%. Risk factors included in the analysis were gender, patient age, crown fracture type, mobility and response to an electric pulp test (EPT) at the initial examination. RESULTS: Teeth with immature root development: The risk of PN was increased in teeth with a concomitant enamel fracture (log-rank test: P = 0.002), enamel-dentin fracture (log-rank test: P < 0.0001), enamel-dentin-pulp fracture (log-rank test: P < 0.0001) and in teeth with no response to EPT at the initial examination [hazard ratio: 21 (95% confidence interval, CI: 2.5-172.5), P = 0.005]. Teeth with mature root development: the risk of PN was increased in teeth with an enamel-dentin fracture [hazard ratio: 12.2 (95% CI: 5.0-29.8), P < 0.0001], infraction [hazard ratio: 5.1 (95% CI: 1.2-21.4) P = 0.04] and in teeth with no response to EPT at the initial examination [hazard ratio: 8 (95% CI: 3.3-19.5), P < 0.0001]. CONCLUSION: A concomitant crown fracture and no response to EPT at the initial examination may be used to identify teeth at increased risk of PN following subluxation injury.

Combination injuries 1. The risk of pulp necrosis in permanent teeth with concussion injuries and concomitant crown fractures.

BACKGROUND: The reported risk of pulp necrosis (PN) is low in teeth with concussion injuries. A concomitant crown fracture may affect the risk of PN. AIM: To analyze the influence of a crown fracture (with and without pulp exposure) on the risk of PN in teeth with concussion injury. MATERIAL: The study included 469 permanent incisors with concussion from 358 patients (226 male, 132 female). Among these, 292 had a concomitant crown fracture (70 with and 222 without pulp exposure). All teeth were examined and treated according to standardized protocol. STATISTICAL ANALYSIS: The risk of PN was analyzed by the Kaplan-Meier method and Cox regression. Risk factors included in the analysis: gender, age, stage of root development, type of crown fracture, and response to electric pulp test (EPT) at the initial examination. The level of significance was set at 5%. RESULTS: The risk of PN was low in teeth with immature root development [1.1%, 95% confidence intervals (CI): 0-3.4]. The following factors significantly increased the risk of PN in teeth with mature root development: crown fracture without pulp exposure [hazard ratio 4.1 (95% CI: 1.4-11.9), P = 0.01] and no response to EPT at the initial examination [hazard ratio 30.7 (95% CI: 7.7-121), P < 0.0001]. The overall risk of PN increased from 3.5% (95% CI: 0.2-6.8) to 11.0% (95% CI: 5.2-16.7) when a concomitant crown fracture without pulp exposure was present. If the tooth had both a crown fracture and gave no response to EPT, the risk further increased to 55.0% (95% CI: 34.3-75.8). CONCLUSION: No response to EPT at the initial examination or a concomitant crown fracture significantly increased the risk of PN in teeth with concussion injury and mature root development. If both risk factors were present there was a synergetic effect.

Combination injuries 3. The risk of pulp necrosis in permanent teeth with extrusion or lateral luxation and concomitant crown fractures without pulp exposure.

AIM: To analyze the influence of a crown fracture without pulp exposure on the risk of pulp necrosis (PN) in teeth with extrusion or lateral luxation. MATERIAL AND METHODS: The study included 82 permanent incisors with extrusion from 78 patients (57 male, 21 female) and 179 permanent incisors with lateral luxation from 149 patients (87 male, 62 female). A total of 25 teeth with extrusion and 33 teeth with lateral luxation had suffered a concomitant crown fracture (infraction, enamel fracture or enamel-dentin-fracture). All the teeth were examined and treated according to a standardized protocol. STATISTICS: The risk of PN was analyzed separately for teeth with immature and mature root development by the Kaplan-Meier method, the log-rank test and Cox regression (lateral luxation only). The level of significance was set at 5%. Risk factors included in the analysis were gender, age, crown fracture, and response to electric pulp test at the initial examination. RESULTS: A concomitant crown fracture significantly increased the risk of PN in teeth with lateral luxation. For teeth with immature root development (hazard ratio: 10 [95% confidence interval (CI): 1.1-100] P = 0.04), the overall risk increased from 4.7% (95% CI: 0-10.8) to 40% (95% CI: 2.8-77.2). For teeth with mature root development [hazard ratio: 2.4 (95% CI: 1.4-4.2) P < 0.001], the overall risk increased from 65.1% (95% CI: 55.2-75.1) to 93% (95% CI: 85.5-100). In teeth with extrusion and mature root development, the overall risk of PN increased from 56.5% (95% CI: 37.7-75.4) to 76.5% (95% CI: 58.9-94) in case of a concomitant crown fracture, but the difference was not statistically significant (P > 0.05). CONCLUSION: A concomitant crown fracture without pulp exposure significantly increased the risk of PN in teeth with lateral luxation. This risk factor may be used to identify teeth at increased risk of PN following lateral luxation injury.