Pulp vitality in teeth suffering trauma during orthodontic therapy.

OBJECTIVE: To examine pulpal vitality in teeth suffering dental trauma during orthodontic therapy with fixed appliances. MATERIALS AND METHODS: Pulpal condition was evaluated in 59 teeth that had suffered dental trauma during orthodontic treatment (TO-group), in 800 orthodontically treated teeth without previous dental trauma (O-group), and in 193 orthodontically untreated teeth with previous dental trauma (T-group). Pulpal vitality was examined clinically and with radiographs. Degree of pulp obliteration was rated as absent, partial, or total. All teeth in the TO-group showed a positive sensibility test prior to resumption of orthodontic therapy. RESULTS: Teeth in the TO-group revealed a significantly higher frequency of pulp necrosis than teeth in the O-group or teeth in the T-group (P < .001, respectively). In the TO-group, teeth with extrusive or lateral luxation (P = .031) and teeth with intrusive luxation (P = .015) injuries showed a significantly higher rate of pulp necrosis than teeth with fracture of enamel. In addition, teeth with total pulp obliteration showed a significantly higher frequency of pulp necrosis than teeth without pulp obliteration (P = .013). CONCLUSION: Teeth with severe periodontal injury during orthodontic therapy and subsequent total pulp obliteration have an increased risk of pulp necrosis during additional orthodontic treatment stages.

Influence of orthodontic intrusion on pulpal vitality of previously traumatized maxillary permanent incisors.

INTRODUCTION: Dental trauma seems to increase a patient's susceptibility to complications during orthodontic treatment. However, no previous investigation has examined the influence of orthodontic intrusion on pulpal vitality of traumatized maxillary permanent incisors. METHODS: Pulpal condition was examined clinically and radiologically after orthodontic intrusion of previously traumatized (OT group) and nontraumatized teeth (O group), and after previous dental trauma without orthodontic treatment (T group). Inclusion criteria for the OT and O groups were Class II Division 1 malocclusion with deep bite and orthodontic intrusion of the maxillary incisors, no extractions of maxillary teeth, and no additional lateral tooth movement of the maxillary incisors. All teeth in the OT group had a positive sensitivity test before orthodontic therapy. RESULTS: Teeth in the OT group, and especially those with severe periodontal injuries, showed a significantly higher frequency of pulp necrosis than teeth in the O and T groups. The occurrence of pulp necrosis was significantly higher in lateral than in central incisors. CONCLUSIONS: Traumatized maxillary incisors, and especially lateral incisors, with severe periodontal injuries have a higher susceptibility to pulp necrosis during orthodontic intrusion than nontraumatized teeth.

The effect of pulp obliteration on pulpal vitality of orthodontically intruded traumatized teeth.

Limited information exists on the impact of pulp obliteration on pulpal vitality of orthodontically treated traumatized teeth. Pulpal condition was examined in 269 traumatized maxillary incisors after orthodontic intrusion (OT group) and in 193 traumatized maxillary incisors without subsequent orthodontic treatment (C group). According to the degree of initial pulp obliteration, the teeth were divided into three categories: teeth without, teeth with partial, and teeth with total pulp obliteration. Teeth in the OT group revealed a significantly higher rate of pulp necrosis than teeth in the C group (p < 0.001). In addition, teeth in the OT group with total pulp obliteration showed a significantly higher rate of pulp necrosis than teeth without (p < 0.001) or only partial pulp obliteration (p = 0.025). The results indicate that traumatized teeth with total pulp obliteration have a higher susceptibility to pulpal complications during orthodontic intrusion than traumatized teeth without or only partial pulp obliteration.

Influence of overjet and lip coverage on the prevalence and severity of incisor trauma.

OBJECTIVE: The aim of this study was to assess the influence of overjet size and lip coverage on the prevalence and severity of incisor trauma. PATIENTS AND METHODS: Dental records made on presentation of 1,367 patients were examined for data concerning the prevalence, type and severity of incisor trauma. Original overjet was measured on the pre-treatment study models and divided into two categories: normal overjet (0-3.0 mm) and increased overjet (> 3.0 mm). Lip coverage of the upper incisors was estimated with reference to photographs showing the patient's face and was then rated as adequate or inadequate. The patients were then divided into three groups: normal original overjet and adequate lip coverage (Group 1), increased original overjet and adequate lip coverage (Group 2), and increased original overjet and inadequate lip coverage (Group 3). RESULTS: Group 1 patients revealed a significantly lower prevalence of traumatic injuries than those in Group 2 (p = 0.028) or Group 3 (p = 0.003), and the odds ratios compared to Group 1 were 1.6634 for Group 2 and 2.0336 for Group 3. Regarding the type of trauma, Group 3 patients showed a significantly higher frequency of periodontal injuries than those in Group 1 (p = 0.018) or Group 2 (p = 0.015). Furthermore, Group 3 patients had significantly more in juries to two or more teeth per person than patients in Group 1 (p < 0.001) or Group 2 (p < 0.001). CONCLUSIONS: Increased overjet and inadequate lip coverage increase the risk and severity of incisor trauma. Early orthodontic treatment might prevent dental trauma in these patients.

Prevalence of traumatic injuries to the permanent incisors in candidates for orthodontic treatment.

The dental records made on presentation of 1367 consecutive patients (731 females and 636 males) for orthodontic treatment at a private orthodontic practice between 1998 and 2002 were examined for data relating to trauma to the permanent incisors. The results showed that 10.3% of these patients had suffered from dental trauma before the onset of orthodontic treatment. The highest prevalence of dental trauma was determined in the 11-15 years age group, corresponding to the dental developmental stage of the late mixed dentition. The most frequently affected teeth were the maxillary central incisors (79.6%), and the most common types of trauma were fracture of enamel-dentin without pulpal involvement (42.7%) and fracture of enamel (33.8%). Compared to patients with normal overjet and adequate lip coverage, the frequency of dental trauma was significantly higher in patients with increased overjet and adequate lip coverage (P = 0.028) or with increased overjet and inadequate lip coverage (P = 0.003). The results of the present study indicate that a significant percentage of candidates for orthodontic treatment, and especially those with increased overjet and inadequate lip coverage, suffer trauma to their permanent incisors before the onset of orthodontic treatment. It might also be concluded that preventive orthodontic treatment of such patients should be initiated and completed before the age of 11, i.e. in the early to middle mixed dentition.