The Saudi Dental Journal (2013) 25, 159–165
King Saud University
The Saudi Dental Journal www.ksu.edu.sa www.sciencedirect.com
CASE REPORT
Clinical manifestations and dental management of dentinogenesis imperfecta associated with osteogenesis imperfecta: Case report Halima Abukabbos
a,*
, Faisal Al-Sineedi
b
a Saudi Board Certificate in Pediatric Dentistry 2010, Qatif Central Hospital, MOH, Sanabes 5403, Tarout 32621-6435, Saudi Arabia b Department of Dentistry, King Fahd Military Medical Complex, P.O. Box 946, Dhahran 31932, Saudi Arabia
Received 15 October 2012; revised 22 June 2013; accepted 17 October 2013 Available online 7 November 2013
KEYWORDS Dentinogenesis imperfecta (DI); Osteogenesis imperfecta (OI); Clinical manifestations; Medical and dental considerations
Abstract Dentinogenesis imperfecta (DI) associated with osteogenesis imperfecta (OI) is a genetic disorder that affects the connective tissues and results in dentine dysplasia. This case report discusses the systemic and dental manifestations of OI and DI in a 4-year-old child, with moderate presentation of both disorders, who was treated at King Fahd Military Medical Complex in Dhahran. Dental treatment included the use of strip and stainless-steel crowns under local anesthesia, as well as behavior modification techniques. Rigorous home care instructions, including reinforcement of the oral hygiene practice and avoidance of any episode that may lead to bone fracture, were discussed with the parents. The case was reevaluated at 3-month follow-up visits, wherein the medical and dental histories were updated, the child’s growth was monitored, periodic clinical and radiographic examinations were performed, and the oral hygiene was evaluated via the debris index score and caries risk assessment. Further treatment of the permanent dentition may be needed in the future. ª 2013 King Saud University. Production and hosting by Elsevier B.V. All rights reserved.
Introduction
* Corresponding author. Tel.: +966 3 8361000, mobile: +966 0567476045. E-mail addresses: [email protected] (H. Abukabbos), [email protected] (F. Al-Sineedi). Peer review under responsibility of King Saud University.
Production and hosting by Elsevier
Dentinogenesis imperfecta (DI) is an inheritable disorder of tooth development that occurs during the histodifferentiation stage. DI results in structural defects in dentin formation in the deciduous or both the deciduous and permanent teeth. The incidence of DI is 1 in 8000. It can be subdivided into three basic forms: Shields types I, II, and III. Shields type I occurs with osteogenesis imperfecta (OI) due to a defect in type I collagen. Shields type II (also known as hereditary opalescent dentin) is the most common type of DI, and it is not associated with OI. Shields type III is very rare and was first diagnosed in
1013-9052 ª 2013 King Saud University. Production and hosting by Elsevier B.V. All rights reserved. http://dx.doi.org/10.1016/j.sdentj.2013.10.004
160 a population in Brandywine, Maryland, USA (Shields et al., 1973). Shields types II and III of DI are caused by a defect in dentin sialophosphoprotein gene (DSPP) (Malmgren and Lindskog, 2003; Kim and Simmer, 2007). OI, also known as ‘‘brittle bone disease,’’ is a genetic disorder that affects the connective tissues. A person with OI experiences recurrent, multiple bone fractures. Different types of OI have been recognized, but most are due to mutations in the COL1A1 and COL1A2 genes, which encode the pro-alpha 1 and 2 polypeptide chains of type I collagen. Ligaments, sclera, bone, and dentin are mainly affected (Niyibizi et al., 2000). Abnormalities frequently seen in patients with OI include hearing loss, blue sclera, weak joints, easily bruising, deficient growth, short stature, DI, asthma, and spinal curvature (Marini, 1988). The incidence of OI is 1 per 20,000– 30,000 live births (Sillence, 1981). In 1979, Sillence et al. classified OI into basic types I–IV. Type I is an autosomal dominant mild form of OI. Patients present at preschool age with blue sclera and hearing deficits in 50% of cases. Type II is an autosomal recessive form, in which patients present with blue sclera and perinatal death. Type III, considered to be the most severe form of the disease, is an autosomal recessive form characterized by a progressive short stature and blue sclera that normalize with age. Type IV is an autosomal dominant form with moderate severity. Patients present with normal sclera and hearing; bowing bones and vertebral fractures are also common findings. Most cases (90%) are classified as type I or IV, with or without involvement of the teeth. Types V–VII have since been added to the original classification system. These types do not have type I collagen mutations, but the patients show microscopically abnormal bone and a similar phenotype (Sillence et al., 1979; Elnagdy et al., 2012). About 50% of children and adults with OI have dental involvement of varying degree and severity (Santili et al., 2005). Although both dentitions may be affected, the deformity is generally more severe in the primary teeth (Waltimo et al., 1996; O’Connell and Marini, 1999). Teeth with DI have certain features, including amber bulbous crowns or graybrown discoloration, constricted cementoenamel junctions, narrow roots, partial or total obliteration of the pulp chambers, and root canals with evidence of periapical radiolucencies. The enamel is normal, but may shear rapidly due to deficient dentinoenamel junction, resulting in dentine attrition and loss of the vertical dimension (Waltimo et al., 1996). In cases with a history of multiple bone fractures, OI should be differentiated from suspected child abuse. To this end, it is vital that the clinician obtains good medical and family histories. Although the incidence of OI is rare, the presence of blue sclera, abnormal teeth, hearing problems, osteoporosis, wormian bones, joint laxity, and short stature can be considered as positive findings of OI, as their presence in child abuse is rare or uncommon. If the child has DI, the clinician should rule out the diagnosis of OI (Gahagan and Rimsza, 1991; Kruse et al., 1997; Lund et al., 2000). This case report describes the clinical manifestations of a 4year-old boy with DI and OI, as well as the child’s medical and dental treatments with 18 months of follow-up after comprehensive dental management at King Fahd Military Medical Complex in Dhahran, KSA. The study was approved by the appropriate ethics committee related to King Fahd Military Medical Complex. Subjects gave their informed consent to participate in the study.
H. Abukabbos, F. Al-Sineedi Case report A 4-year-old boy was referred by a general dentist for comprehensive dental treatment. The child was diagnosed with OI at 19 months of age at King Fahd Military Medical Complex in Dhahran, KSA. Since 3 months of age, he experienced repeated and multiple fractures, especially recurrent fractures of the left femur, with frequent cast applications (Fig. 1a and b). Wormian skull bones (i.e., small puzzle-like pieces of intrasutural skull bones) were seen in his lateral skull radiograph at 19 months of age (Fig. 2). He had a mild bowing abnormality, with curved thin bones in both legs (Fig. 3). However, no bowing of the legs was detected at 4 years of age (Fig. 4). The patient was born after a full-term pregnancy, and his immunizations were up to date. He was crawling at 8 months, walking at 15 months, and weaned at 2 years. No delay in speaking was noted. He was his mother’s fourth live birth, and no member of his family has the same disability. Systemic findings were unremarkable (Table 1). The child was on cyclic therapy with pamidronate (10 mg by intravenous infusion over 6 h OD), oral vitamin D3 (400 IU, OD), and oral calcium (200 IU) every 3 months. Past dental history included extraction of tooth #74 under local anesthesia due to a dentoalveolar abscess and after the use of augmentin (156 mg/5 cc TID for 7 days), and pulpotomy of tooth #84 with negative behavior. Orofacial clinical examination revealed mild bitemporal bossing with a convex facial profile, competent lips, and eyes with normal sclera (Fig. 5a and b). There was no evidence of rib fracture or upper rib abnormality. Lymph nodes were palpable on both sides. The tongue, lingual frenum, soft and hard palates, and tonsils were all normal. Intra-oral examination showed a dentoalveolar abscess related to tooth #64 in U-shaped upper and lower arches, with generalized marginal gingivitis. The debris index score was 32 (Fig. 6a and b). The patient had a mesial step terminal plane with a class I canine relationship on both sides. The midline was coincident, with a 50% overbite and 2 mm overjet (Fig. 7a–c). The teeth were brown-gray in color, with constricted bulbous crowns and attrition. Radiographic examination included full-mouth radiographs, two posterior bitwings, four periapical radiographs for the posterior teeth, and two periapical radiographs for the anterior teeth. OPG could not be performed because the child was too small to fit in the OPG machine. Radiographically, the primary teeth appeared to have short constricted roots, dentine hyperatrophy, and partially obliterated pulp. The presence of the developed permanent teeth buds was also evident. The child’s dental age by radiography was similar to his chronological age. Evaluation of the periapical X-rays revealed normally developing occlusion, no supernumerary teeth, and the presence of unerupted upper and lower first permanent molars and permanent canines (Fig. 8). The patient was treated in the dental clinic under local anesthesia (xylocaine 2% with epinephrine 1:100,000). Behavior modification techniques included the tell-show-do technique, positive reinforcement, distraction, and (sometimes) voice control. Treatment was divided into 10 visits. Teeth #55, 54, 65, 75, 84, and 85 were protected with stainless-steel crowns. Tooth #64 was extracted due to the presence of a dentoalveolar abscess. Teeth #51, 52, 61, 62, 71, 72, 81, and 82 were covered with celluloid strip crowns. Teeth #53, 63, 73, and 83 had
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Figure 1 (a and b) The child was diagnosed with osteogenesis imperfecta at his 19th month with presentation of repeated and multiple fractures (recurrent left femur fracture since he was 3 months old with frequent cast application).
Figure 4 Figure 2 Lateral skull radiograph shows wormian skull bones (puzzle piece intrasutural skull bones) at age 19 months.
Figure 3
Mild bowing legs at 19 months of age.
composite build-up. Band-and-loop space maintainers were cemented between teeth #63 and 65 and between #73 and 75 (Fig. 9a–c). Preventive measures included oral hygiene practice (i.e., brushing and flossing twice daily) and diet modification
Table 1
No bowing of the legs was detected at age 4 years.
Laboratory examination (chemistry).
Test
Result
Normal range
Reflo Sodium Potassium Chloride Creatinine Osmolality Calcium Magnesium Phosphate
4.8 mmol/l 146 mmol/l 4.2 mmol/l 108 mmol/l 23 umol/l 289 mosm/kg 1.9 mmol/l (fl) 0.89 mmol/l 1.86 mmol/l (›)
3.6–6.1 mmol/l 138–145 mmol/l 3.5–7.8 mmol/l 98–107 mmol/l 71–115 umol/l 275–295 mosm/kg 2.25–2.64 mmol/l 0.7–1 mmol/l 0.8–1.6 mmol/l
(i.e., decreased refined carbohydrate intake and increased healthy food consumption). Professional topical fluoride was applied semiannually. Anticipatory guidance and recall visits were done every 3 months in the maintenance phase because the child was classified as being at high risk of caries (Figs. 10 and 11). During the recall visits, the child’s growth was observed with a growth chart. At his initial visit, the child was 102 cm tall and 16 kg in weight. At the last follow-up visit (after 18 months), the child’s height and weight increased to 113 cm and 18.5 kg, respectively (50% growth chart percentile). The patient reported taking the same medications. His parents are careful to prevent
162
H. Abukabbos, F. Al-Sineedi
Figure 5
(a and b) Mild bitemporal bossing with convex facial profile, competent lips and eyes with normal sclera.
Figure 6
(a and b) Upper and lower arches with brown/gray mottled primary teeth.
Figure 7 (a–c) Mesial step terminal plane and class I canine relationship in both sides with yellow brown opalescent discoloration and rapid wear.
any accident that may lead to bone fracture. Intra-oral examination revealed good oral hygiene practice. The debris index score decreased from 32 (initial visit) to 18 (final visit). A preventive program was planned to prevent or reduce the number of new carious lesions and to improve gingival health. To reduce the microbial flora, plaque was disclosed at the initial dental visit and demonstrated to the parents and child. Oral hygiene instructions for brushing and flossing were provided to both the parents and child. Instructions included the use of the scrub technique with a youth multi-tufted soft nylon toothbrush and ADA-approved fluoridated tooth paste at least twice a day, with at least one brushing performed by a parent, and flossing under the parent’s supervision. In-office prophylaxis and topical fluoride treatment were recommended at 6-month intervals until the caries rate declined substantially. It was recommended that snack frequency and fermentable carbohydrate ingestion can be reduced.
Discussion OI should be diagnosed as early as possible because the genetic mutations can be manifested clinically with varying degrees of severity. However, a diagnosis of OI can be difficult, especially if the family history is negative. Thorough clinical examination and genetic counseling can aid in the diagnosis. Many studies have found no difference in OI incidence between genders or ethnic groups. Multiple bone fractures may be seen more frequently in patients with OI; therefore, OI should be differentiated from osteoporosis (Rauch and Glorieux, 2004). Severe types of OI are usually associated with malocclusion due to abnormal craniofacial characteristics (Michael, 1998). In one report, class III malocclusions occurred in 70–80% of types III and IV OI cases, with a high incidence of anterior and posterior crossbites and open bites. A delay in dental development was observed in 21% of patients with type III
Clinical manifestations and dental management
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Figure 8 Full mouth radiographs showed the primary teeth appeared with short constricted roots, dentine hyperatrophy, partially obliterated pulp and the presence of the developed permanent teeth buds was also evident.
Figure 9
(a–c) Restoration of the primary teeth with anterior strip crowns and posterior stainless steel crowns.
Figure 10
Maintenance phase: recall visit after 3 months.
OI, whereas accelerated development was noted in 23% of patients with type IV OI (O’Connell and Marini, 1999). Sex hormones play a major role in decreasing the rate of bone fracture in the adolescence period; however, due to the diminishing role of these hormones during menopause, OI symptoms usually increase during this time period (Bischoff et al., 1999; Iwamoto et al., 2004). Children with OI are seen by multiple specialists, including, but not limited to, pediatricians, orthopedic surgeons, physical therapists, and psychologists. Treatment
approaches involve physiotherapy, splinting of broken bones, and medications (e.g., bisphosphonate, growth hormones, and vitamin D). There is no cure for OI (Rauch et al., 2003; Iwamoto et al., 2004; Huber, 2007). According to the classification scheme developed by Sillence et al. (1979), our patient can be classified as having type IV OI. He had moderate deformity with normal sclera and hearing, bowing bones, a history of recurrent femur fractures, and dental involvement. Medically, the child was managed
164
H. Abukabbos, F. Al-Sineedi
Figure 11
Recall visit after 18 months. Notice the eruption of the lower permanent incisors with the same problem.
with pamidronate (a bisphosphonate) and vitamin D. Casts were placed to splint and support the broken femur. Thereafter, he was seen by a rehabilitation specialist. DI involves various microscopic changes in the dentinal morphology (Waltimo et al., 1996; Sapir and Shapira, 2007). Compared to the permanent dentition, the primary dentition is more frequently damaged and subjected to rapid wear, particularly when the expression is part of OI (shields type I). Dental defects are the most noticeable clinical signs of OI (O’Connell and Marini, 1999). In one-third of the cases, there is also a defect in the calcification of the enamel (e.g., hypomineralization or hypoplasia) (Schwartz and Tsipouras, 1984). The progression of carious lesions in the affected teeth is slow, mainly due to the rapid attrition of the defected dentine (Hodge et al., 1940). Careful radiographic examination is essential, as pulp calcifications may reveal a possible diagnosis of OI (Lindau et al., 1999). Teeth with obliterated pulp and root canals should undergo endodontic treatment (when indicated) as soon as possible after the defects are discovered because a delay in intervention may lead to a poor prognosis (Pettiette et al., 1988). DI can have variable presentations, with different levels of attrition and discoloration (Sapir and Shapira, 2001). The early treatment of teeth with DI should aim to ensure good occlusion and esthetics, favorable growth of the facial bones and tempromandibular joints, and a favorable condition for the eruption of the permanent successors. Treatment includes caries prevention, attrition observation, monitoring the development of the craniofacial skeleton, and placement of artificial crowns to prevent excessive loss of the tooth structure when the deciduous teeth begin to wear (Levin, 1981; Ranta et al., 1993; Sapir and Shapira, 2001). In the present case study, the deciduous teeth manifested multiple carious lesions, attrition, and rapid wear. Two primary first molars were extracted due to the presence of dentoalveolar abscesses. Thus, we chose to protect the primary molars with stainless-steel crowns and the anterior teeth with celluloid strip crowns. In children and adolescents, comprehensive management should include active follow-up and observation, involving oral hygiene instructions and dietary consultation. Pediatric dentistry, orthodontics, perioprosthetics, and psychology departments may all play roles in the treatment. The
management should be matched to the severity of the clinical expression of the disease. Most cases are severe and demand early restoration of the posterior teeth with stainless-steel crowns. In the anterior dentition, a celluloid strip may suffer from retention problems. Laboratory acrylic crowns placed via the indirect technique may provide more retention, with better long-term esthetic results. Stainless-steel anterior crowns with composite facings may also be considered (Sapir and Shapira, 2007; Tim Wright, 1992). During the mixed-dentition stage, the permanent molars should be restored with stainless-steel crowns, whereas the permanent anterior teeth should be covered with composite as soon as they start to erupt. Restoration of the permanent anterior teeth with celluloid strip or polycarbonate crowns is preferred. At a later stage when the growth is complete, prosthetic restoration of the permanent teeth with porcelainfused metal crowns can be considered (Mars and Smith, 1982). In this case, the primary posterior teeth were restored with stainless-steel crowns, and the anterior teeth were covered with celluloid strip crowns as a simple and time-saving procedure that provided good esthetics and retention at the 18month follow-up visit. External bleaching with carbamide peroxide has been reported, with excellent results (Sapir and Shapira, 2007). Cases with severe loss of the vertical dimension can be treated with comprehensive restorative procedures to restore a more normal occlusion and craniofacial skeleton. Overdenture construction should be considered for cases with excessive loss of the tooth structure. Some teeth with DI may develop periapical abscesses; in these cases, regular radiographic examinations are indicated, as these teeth may need endodontic intervention and apical surgery (Rivers and Staffanou, 1985). In the present case, the upper and lower first primary molars on the left side developed periapical abscesses and were extracted. Bouvier et al. (2008) published a case report of long-term rehabilitation in a child with DI. At age 6 years, the patient’s primary second and permanent first molars were protected with stainless-steel crowns to increase the vertical dimension and to protect them from further attrition. All remaining permanent anterior teeth and premolars were crowned immediately after eruption with polycarbonate resin crowns, while the second molars were protected with stainless-steel crowns.
Clinical manifestations and dental management At age 14.5 years, the child began long-term prosthetic rehabilitation once the maxillary growth was determined to be stable. All provisional crowns were removed, and dental preparations were completed for individual low-fusion ceramic–metal crowns. Maxillary molars were fitted with ceramic crowns with metal occlusal surfaces. In conclusion, shields type I DI associated with OI is a hereditary disorder characterized by fragile bones and dentin dysplasia. Patients with this condition should be diagnosed and managed as soon as possible when the primary teeth start to erupt. Comprehensive medical and dental care should be provided, with full coordination among the pediatricians, dentists, and multiple specialties, to prevent dental diseases, maintain esthetics, occlusion, and function, and reduce tooth wear and hypersensitivity from childhood through adulthood. Conflict of interest We wish to confirm that there are no known conflicts of interest associated with this publication and there has been no significant financial support for this work that could have influenced its outcome. References Bischoff, H., Freitag, P., Jundt, G., Steinmann, B., Tyndall, A., Theiler, R., 1999. Type I osteogenesis imperfecta: diagnostic difficulties. Clin. Rheumatol. 18 (1), 48–51. Bouvier, D., Leheis, B., Duprez, J.P., Bittar, E., Coudert, J.L., 2008. Dentinogenesis imperfecta: long-term rehabilitation in a child. J. Dent. Child (Chic). 75 (2), 192–196. Elnagdy, G., ELRefaiey, M., Aglan, M., Ibrahim, R., ELBadry, T., 2012. Oro-dental manifestations in different types of osteogenesis imperfect. Austr. J. Basic Appl. Sci. 6 (12), 464–473. Gahagan, S., Rimsza, M.E., 1991. Child abuse or osteogenesis imperfect: how can we tell? Pediatrics 88 (5), 987–992. Hodge, H., Finn, S., Robinson, B.G., 1940. Hereditary opalescent dentin, III: histological, chemical and physical studies. J. Dent. Res. 19 (6), 521–536. Huber, M.A., 2007. Osteogenesis imperfecta. Oral Surg. Oral Med. Oral Pathol. Oral Radiol. Endod. 103 (3), 314–320. Iwamoto, J., Takeda, T., Sato, Y., 2004. Effect of treatment with alendronate in osteogenesis imperfecta type 1: a case report. Keio J. Med. 53 (4), 251–255. Tim Wright, J., 1992. The diagnosis and treatment of dentinogenesis imperfect and amelogenesis imperfect. Hellenic Dent. J. 2, 17–24. Kim, J.W., Simmer, J.P., 2007. Hereditary dentin defects. J. Dent. Res. 86 (5), 392–399. Kruse, R.W., Harcke, H.T., Minch, C.M., 1997. Osteogenesis imperfecta (OI), may be mistaken for child abuse. Pediatr. Emerg. Care 13 (3), 244–245. Levin, L.S., 1981. The dentition in the osteogenesis imperfecta syndromes. Clin. Orthop. Relat. Res. 159, 64–74. Lindau, B., Dietz, W., Lundgren, T., Storhaug, K., Noren, J.G., 1999. Discrimination of morphological findings in dentine from osteogenesis imperfecta patients using combinations of polarized light
165 microscopy, microradiography and scanning electron microscopy. Int. J. Paediatr. Dent. 9 (4), 253–261. Lund, A.M., Skovby, F., Knudsen, F.U., 2000. Child abuse and osteogenesis imperfect. How do we distinguish? Ugeskr Laeger 162 (11), 1528–1533. Malmgren, B., Lindskog, S., 2003. Assessment of dysplastic dentin in osteogenesis imperfecta and dentinogenesis imperfecta. Acta Odontol. Scand. 61 (2), 72–80. Marini, J.C., 1988. Osteogenesis imperfecta: comprehensive management. Adv. Pediatr. 35, 391–426. Mars, M., Smith, B.G.N., 1982. Dentinogenesis imperfecta: an integrated conservative approach to treatment. Br. Dent. 152, 15– 18. Michael, D.C., 1998. Dentinogenesis imperfecta: a case report. Am. J. Orthod. Dentofacial Orthop. 113, 367–371. Niyibizi, C., Smith, P., Mi, Z., Robbins, P., Evans, C., 2000. Potential of gene therapy for treating osteogenesis imperfecta. Clin. Orthop. Relat. Res. (379 Suppl.), S126–S133. O’Connell, A.C., Marini, J.C., 1999. Evaluation of oral problems in an osteogenesis imperfecta population. Oral Surg. Oral Med. Oral Pathol. Oral Radiol. Endod. 87 (2), 189–196. Pettiette, M.T., Wright, J.T., Trope, M., 1988. Dentinogenesis imperfecta: endodontic implications – case report. Oral Surg. Oral Med. Oral Pathol. Oral Radiol. Endod. 86 (6), 733–737. Ranta, H., Lukinmaa, P.L., Waltimo, J., 1993. Heritable dentin defects: nosology, pathology, and treatment. Am. J. Med. Genet. 45 (2), 193–200. Rauch, F., Plotkin, H., Travers, R., Zeitlin, L., Glorieux, F.H., 2003. Osteogenosis imperfecta types I, III and IV: effect of pamidronate therapy on bone and mineral metabolism. J. Clin. Endocrinal Metab. 88 (3), 986–992. Rauch, F., Glorieux, F.H., 2004. Osteogenesis imperfecta. Lancet 363 (9418), 1377–1385. Rivers, J.A., Staffanou, R.S., 1985. Restorative treatment of dentinogenesis imperfecta in a young adult. Comp. Cont. Ed. 6, 548–558. Santili, C., Akkari, M., Waisberg, G., Bastos Junior, J.O., Ferreira, W.M., 2005. Clinical, radiographic and laboratory evaluation of patients with osteogenesis imperfecta. Rev. Assoc. Med. Bras. 51 (4), 214–220. Sapir, S., Shapira, J., 2001. Dentinogenesis imperfecta: an early treatment strategy. Pediatr. Dent. 23 (3), 232–237. Sapir, S., Shapira, J., 2007. Clinical solutions for developmental defects of enamel and dentine in children. Pediatr. Dent. 29 (4), 330–336. Schwartz, S., Tsipouras, P., 1984. Oral findings in osteogenesis imperfecta. Oral Surg. Oral Med. Oral Pathol. 57, 161–167. Shields, E.D., Bixler, D., El-Kafrawy, A.M., 1973. A proposed classification for heritable human dentine defects with a description of a new entity. Arch. Oral. Biol. 18 (4), 543–553. Sillence, D.O., Senn, A., Danks, D.M., 1979. Genetic heterogeneity in osteogenesis imperfecta. J. Med. Genet. 16 (2), 101–116. Sillence, D.O., 1981. Osteogenesis imperfecta: an expanding panorama of variants. Clin. Orthop. Relat. Res. 159, 11–25. Waltimo, J., Ojanotko-Harri, A., Lukinmaa, P.L., 1996. Mild forms of dentinogenesis imperfecta in association with osteogenesis imperfecta as characterized by light and transmission electron microscopy. J. Oral Pathol. Med. 25 (5), 256–264.
King Saud University
The Saudi Dental Journal www.ksu.edu.sa www.sciencedirect.com
CASE REPORT
Clinical manifestations and dental management of dentinogenesis imperfecta associated with osteogenesis imperfecta: Case report Halima Abukabbos
a,*
, Faisal Al-Sineedi
b
a Saudi Board Certificate in Pediatric Dentistry 2010, Qatif Central Hospital, MOH, Sanabes 5403, Tarout 32621-6435, Saudi Arabia b Department of Dentistry, King Fahd Military Medical Complex, P.O. Box 946, Dhahran 31932, Saudi Arabia
Received 15 October 2012; revised 22 June 2013; accepted 17 October 2013 Available online 7 November 2013
KEYWORDS Dentinogenesis imperfecta (DI); Osteogenesis imperfecta (OI); Clinical manifestations; Medical and dental considerations
Abstract Dentinogenesis imperfecta (DI) associated with osteogenesis imperfecta (OI) is a genetic disorder that affects the connective tissues and results in dentine dysplasia. This case report discusses the systemic and dental manifestations of OI and DI in a 4-year-old child, with moderate presentation of both disorders, who was treated at King Fahd Military Medical Complex in Dhahran. Dental treatment included the use of strip and stainless-steel crowns under local anesthesia, as well as behavior modification techniques. Rigorous home care instructions, including reinforcement of the oral hygiene practice and avoidance of any episode that may lead to bone fracture, were discussed with the parents. The case was reevaluated at 3-month follow-up visits, wherein the medical and dental histories were updated, the child’s growth was monitored, periodic clinical and radiographic examinations were performed, and the oral hygiene was evaluated via the debris index score and caries risk assessment. Further treatment of the permanent dentition may be needed in the future. ª 2013 King Saud University. Production and hosting by Elsevier B.V. All rights reserved.
Introduction
* Corresponding author. Tel.: +966 3 8361000, mobile: +966 0567476045. E-mail addresses: [email protected] (H. Abukabbos), [email protected] (F. Al-Sineedi). Peer review under responsibility of King Saud University.
Production and hosting by Elsevier
Dentinogenesis imperfecta (DI) is an inheritable disorder of tooth development that occurs during the histodifferentiation stage. DI results in structural defects in dentin formation in the deciduous or both the deciduous and permanent teeth. The incidence of DI is 1 in 8000. It can be subdivided into three basic forms: Shields types I, II, and III. Shields type I occurs with osteogenesis imperfecta (OI) due to a defect in type I collagen. Shields type II (also known as hereditary opalescent dentin) is the most common type of DI, and it is not associated with OI. Shields type III is very rare and was first diagnosed in
1013-9052 ª 2013 King Saud University. Production and hosting by Elsevier B.V. All rights reserved. http://dx.doi.org/10.1016/j.sdentj.2013.10.004
160 a population in Brandywine, Maryland, USA (Shields et al., 1973). Shields types II and III of DI are caused by a defect in dentin sialophosphoprotein gene (DSPP) (Malmgren and Lindskog, 2003; Kim and Simmer, 2007). OI, also known as ‘‘brittle bone disease,’’ is a genetic disorder that affects the connective tissues. A person with OI experiences recurrent, multiple bone fractures. Different types of OI have been recognized, but most are due to mutations in the COL1A1 and COL1A2 genes, which encode the pro-alpha 1 and 2 polypeptide chains of type I collagen. Ligaments, sclera, bone, and dentin are mainly affected (Niyibizi et al., 2000). Abnormalities frequently seen in patients with OI include hearing loss, blue sclera, weak joints, easily bruising, deficient growth, short stature, DI, asthma, and spinal curvature (Marini, 1988). The incidence of OI is 1 per 20,000– 30,000 live births (Sillence, 1981). In 1979, Sillence et al. classified OI into basic types I–IV. Type I is an autosomal dominant mild form of OI. Patients present at preschool age with blue sclera and hearing deficits in 50% of cases. Type II is an autosomal recessive form, in which patients present with blue sclera and perinatal death. Type III, considered to be the most severe form of the disease, is an autosomal recessive form characterized by a progressive short stature and blue sclera that normalize with age. Type IV is an autosomal dominant form with moderate severity. Patients present with normal sclera and hearing; bowing bones and vertebral fractures are also common findings. Most cases (90%) are classified as type I or IV, with or without involvement of the teeth. Types V–VII have since been added to the original classification system. These types do not have type I collagen mutations, but the patients show microscopically abnormal bone and a similar phenotype (Sillence et al., 1979; Elnagdy et al., 2012). About 50% of children and adults with OI have dental involvement of varying degree and severity (Santili et al., 2005). Although both dentitions may be affected, the deformity is generally more severe in the primary teeth (Waltimo et al., 1996; O’Connell and Marini, 1999). Teeth with DI have certain features, including amber bulbous crowns or graybrown discoloration, constricted cementoenamel junctions, narrow roots, partial or total obliteration of the pulp chambers, and root canals with evidence of periapical radiolucencies. The enamel is normal, but may shear rapidly due to deficient dentinoenamel junction, resulting in dentine attrition and loss of the vertical dimension (Waltimo et al., 1996). In cases with a history of multiple bone fractures, OI should be differentiated from suspected child abuse. To this end, it is vital that the clinician obtains good medical and family histories. Although the incidence of OI is rare, the presence of blue sclera, abnormal teeth, hearing problems, osteoporosis, wormian bones, joint laxity, and short stature can be considered as positive findings of OI, as their presence in child abuse is rare or uncommon. If the child has DI, the clinician should rule out the diagnosis of OI (Gahagan and Rimsza, 1991; Kruse et al., 1997; Lund et al., 2000). This case report describes the clinical manifestations of a 4year-old boy with DI and OI, as well as the child’s medical and dental treatments with 18 months of follow-up after comprehensive dental management at King Fahd Military Medical Complex in Dhahran, KSA. The study was approved by the appropriate ethics committee related to King Fahd Military Medical Complex. Subjects gave their informed consent to participate in the study.
H. Abukabbos, F. Al-Sineedi Case report A 4-year-old boy was referred by a general dentist for comprehensive dental treatment. The child was diagnosed with OI at 19 months of age at King Fahd Military Medical Complex in Dhahran, KSA. Since 3 months of age, he experienced repeated and multiple fractures, especially recurrent fractures of the left femur, with frequent cast applications (Fig. 1a and b). Wormian skull bones (i.e., small puzzle-like pieces of intrasutural skull bones) were seen in his lateral skull radiograph at 19 months of age (Fig. 2). He had a mild bowing abnormality, with curved thin bones in both legs (Fig. 3). However, no bowing of the legs was detected at 4 years of age (Fig. 4). The patient was born after a full-term pregnancy, and his immunizations were up to date. He was crawling at 8 months, walking at 15 months, and weaned at 2 years. No delay in speaking was noted. He was his mother’s fourth live birth, and no member of his family has the same disability. Systemic findings were unremarkable (Table 1). The child was on cyclic therapy with pamidronate (10 mg by intravenous infusion over 6 h OD), oral vitamin D3 (400 IU, OD), and oral calcium (200 IU) every 3 months. Past dental history included extraction of tooth #74 under local anesthesia due to a dentoalveolar abscess and after the use of augmentin (156 mg/5 cc TID for 7 days), and pulpotomy of tooth #84 with negative behavior. Orofacial clinical examination revealed mild bitemporal bossing with a convex facial profile, competent lips, and eyes with normal sclera (Fig. 5a and b). There was no evidence of rib fracture or upper rib abnormality. Lymph nodes were palpable on both sides. The tongue, lingual frenum, soft and hard palates, and tonsils were all normal. Intra-oral examination showed a dentoalveolar abscess related to tooth #64 in U-shaped upper and lower arches, with generalized marginal gingivitis. The debris index score was 32 (Fig. 6a and b). The patient had a mesial step terminal plane with a class I canine relationship on both sides. The midline was coincident, with a 50% overbite and 2 mm overjet (Fig. 7a–c). The teeth were brown-gray in color, with constricted bulbous crowns and attrition. Radiographic examination included full-mouth radiographs, two posterior bitwings, four periapical radiographs for the posterior teeth, and two periapical radiographs for the anterior teeth. OPG could not be performed because the child was too small to fit in the OPG machine. Radiographically, the primary teeth appeared to have short constricted roots, dentine hyperatrophy, and partially obliterated pulp. The presence of the developed permanent teeth buds was also evident. The child’s dental age by radiography was similar to his chronological age. Evaluation of the periapical X-rays revealed normally developing occlusion, no supernumerary teeth, and the presence of unerupted upper and lower first permanent molars and permanent canines (Fig. 8). The patient was treated in the dental clinic under local anesthesia (xylocaine 2% with epinephrine 1:100,000). Behavior modification techniques included the tell-show-do technique, positive reinforcement, distraction, and (sometimes) voice control. Treatment was divided into 10 visits. Teeth #55, 54, 65, 75, 84, and 85 were protected with stainless-steel crowns. Tooth #64 was extracted due to the presence of a dentoalveolar abscess. Teeth #51, 52, 61, 62, 71, 72, 81, and 82 were covered with celluloid strip crowns. Teeth #53, 63, 73, and 83 had
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Figure 1 (a and b) The child was diagnosed with osteogenesis imperfecta at his 19th month with presentation of repeated and multiple fractures (recurrent left femur fracture since he was 3 months old with frequent cast application).
Figure 4 Figure 2 Lateral skull radiograph shows wormian skull bones (puzzle piece intrasutural skull bones) at age 19 months.
Figure 3
Mild bowing legs at 19 months of age.
composite build-up. Band-and-loop space maintainers were cemented between teeth #63 and 65 and between #73 and 75 (Fig. 9a–c). Preventive measures included oral hygiene practice (i.e., brushing and flossing twice daily) and diet modification
Table 1
No bowing of the legs was detected at age 4 years.
Laboratory examination (chemistry).
Test
Result
Normal range
Reflo Sodium Potassium Chloride Creatinine Osmolality Calcium Magnesium Phosphate
4.8 mmol/l 146 mmol/l 4.2 mmol/l 108 mmol/l 23 umol/l 289 mosm/kg 1.9 mmol/l (fl) 0.89 mmol/l 1.86 mmol/l (›)
3.6–6.1 mmol/l 138–145 mmol/l 3.5–7.8 mmol/l 98–107 mmol/l 71–115 umol/l 275–295 mosm/kg 2.25–2.64 mmol/l 0.7–1 mmol/l 0.8–1.6 mmol/l
(i.e., decreased refined carbohydrate intake and increased healthy food consumption). Professional topical fluoride was applied semiannually. Anticipatory guidance and recall visits were done every 3 months in the maintenance phase because the child was classified as being at high risk of caries (Figs. 10 and 11). During the recall visits, the child’s growth was observed with a growth chart. At his initial visit, the child was 102 cm tall and 16 kg in weight. At the last follow-up visit (after 18 months), the child’s height and weight increased to 113 cm and 18.5 kg, respectively (50% growth chart percentile). The patient reported taking the same medications. His parents are careful to prevent
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Figure 5
(a and b) Mild bitemporal bossing with convex facial profile, competent lips and eyes with normal sclera.
Figure 6
(a and b) Upper and lower arches with brown/gray mottled primary teeth.
Figure 7 (a–c) Mesial step terminal plane and class I canine relationship in both sides with yellow brown opalescent discoloration and rapid wear.
any accident that may lead to bone fracture. Intra-oral examination revealed good oral hygiene practice. The debris index score decreased from 32 (initial visit) to 18 (final visit). A preventive program was planned to prevent or reduce the number of new carious lesions and to improve gingival health. To reduce the microbial flora, plaque was disclosed at the initial dental visit and demonstrated to the parents and child. Oral hygiene instructions for brushing and flossing were provided to both the parents and child. Instructions included the use of the scrub technique with a youth multi-tufted soft nylon toothbrush and ADA-approved fluoridated tooth paste at least twice a day, with at least one brushing performed by a parent, and flossing under the parent’s supervision. In-office prophylaxis and topical fluoride treatment were recommended at 6-month intervals until the caries rate declined substantially. It was recommended that snack frequency and fermentable carbohydrate ingestion can be reduced.
Discussion OI should be diagnosed as early as possible because the genetic mutations can be manifested clinically with varying degrees of severity. However, a diagnosis of OI can be difficult, especially if the family history is negative. Thorough clinical examination and genetic counseling can aid in the diagnosis. Many studies have found no difference in OI incidence between genders or ethnic groups. Multiple bone fractures may be seen more frequently in patients with OI; therefore, OI should be differentiated from osteoporosis (Rauch and Glorieux, 2004). Severe types of OI are usually associated with malocclusion due to abnormal craniofacial characteristics (Michael, 1998). In one report, class III malocclusions occurred in 70–80% of types III and IV OI cases, with a high incidence of anterior and posterior crossbites and open bites. A delay in dental development was observed in 21% of patients with type III
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Figure 8 Full mouth radiographs showed the primary teeth appeared with short constricted roots, dentine hyperatrophy, partially obliterated pulp and the presence of the developed permanent teeth buds was also evident.
Figure 9
(a–c) Restoration of the primary teeth with anterior strip crowns and posterior stainless steel crowns.
Figure 10
Maintenance phase: recall visit after 3 months.
OI, whereas accelerated development was noted in 23% of patients with type IV OI (O’Connell and Marini, 1999). Sex hormones play a major role in decreasing the rate of bone fracture in the adolescence period; however, due to the diminishing role of these hormones during menopause, OI symptoms usually increase during this time period (Bischoff et al., 1999; Iwamoto et al., 2004). Children with OI are seen by multiple specialists, including, but not limited to, pediatricians, orthopedic surgeons, physical therapists, and psychologists. Treatment
approaches involve physiotherapy, splinting of broken bones, and medications (e.g., bisphosphonate, growth hormones, and vitamin D). There is no cure for OI (Rauch et al., 2003; Iwamoto et al., 2004; Huber, 2007). According to the classification scheme developed by Sillence et al. (1979), our patient can be classified as having type IV OI. He had moderate deformity with normal sclera and hearing, bowing bones, a history of recurrent femur fractures, and dental involvement. Medically, the child was managed
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Figure 11
Recall visit after 18 months. Notice the eruption of the lower permanent incisors with the same problem.
with pamidronate (a bisphosphonate) and vitamin D. Casts were placed to splint and support the broken femur. Thereafter, he was seen by a rehabilitation specialist. DI involves various microscopic changes in the dentinal morphology (Waltimo et al., 1996; Sapir and Shapira, 2007). Compared to the permanent dentition, the primary dentition is more frequently damaged and subjected to rapid wear, particularly when the expression is part of OI (shields type I). Dental defects are the most noticeable clinical signs of OI (O’Connell and Marini, 1999). In one-third of the cases, there is also a defect in the calcification of the enamel (e.g., hypomineralization or hypoplasia) (Schwartz and Tsipouras, 1984). The progression of carious lesions in the affected teeth is slow, mainly due to the rapid attrition of the defected dentine (Hodge et al., 1940). Careful radiographic examination is essential, as pulp calcifications may reveal a possible diagnosis of OI (Lindau et al., 1999). Teeth with obliterated pulp and root canals should undergo endodontic treatment (when indicated) as soon as possible after the defects are discovered because a delay in intervention may lead to a poor prognosis (Pettiette et al., 1988). DI can have variable presentations, with different levels of attrition and discoloration (Sapir and Shapira, 2001). The early treatment of teeth with DI should aim to ensure good occlusion and esthetics, favorable growth of the facial bones and tempromandibular joints, and a favorable condition for the eruption of the permanent successors. Treatment includes caries prevention, attrition observation, monitoring the development of the craniofacial skeleton, and placement of artificial crowns to prevent excessive loss of the tooth structure when the deciduous teeth begin to wear (Levin, 1981; Ranta et al., 1993; Sapir and Shapira, 2001). In the present case study, the deciduous teeth manifested multiple carious lesions, attrition, and rapid wear. Two primary first molars were extracted due to the presence of dentoalveolar abscesses. Thus, we chose to protect the primary molars with stainless-steel crowns and the anterior teeth with celluloid strip crowns. In children and adolescents, comprehensive management should include active follow-up and observation, involving oral hygiene instructions and dietary consultation. Pediatric dentistry, orthodontics, perioprosthetics, and psychology departments may all play roles in the treatment. The
management should be matched to the severity of the clinical expression of the disease. Most cases are severe and demand early restoration of the posterior teeth with stainless-steel crowns. In the anterior dentition, a celluloid strip may suffer from retention problems. Laboratory acrylic crowns placed via the indirect technique may provide more retention, with better long-term esthetic results. Stainless-steel anterior crowns with composite facings may also be considered (Sapir and Shapira, 2007; Tim Wright, 1992). During the mixed-dentition stage, the permanent molars should be restored with stainless-steel crowns, whereas the permanent anterior teeth should be covered with composite as soon as they start to erupt. Restoration of the permanent anterior teeth with celluloid strip or polycarbonate crowns is preferred. At a later stage when the growth is complete, prosthetic restoration of the permanent teeth with porcelainfused metal crowns can be considered (Mars and Smith, 1982). In this case, the primary posterior teeth were restored with stainless-steel crowns, and the anterior teeth were covered with celluloid strip crowns as a simple and time-saving procedure that provided good esthetics and retention at the 18month follow-up visit. External bleaching with carbamide peroxide has been reported, with excellent results (Sapir and Shapira, 2007). Cases with severe loss of the vertical dimension can be treated with comprehensive restorative procedures to restore a more normal occlusion and craniofacial skeleton. Overdenture construction should be considered for cases with excessive loss of the tooth structure. Some teeth with DI may develop periapical abscesses; in these cases, regular radiographic examinations are indicated, as these teeth may need endodontic intervention and apical surgery (Rivers and Staffanou, 1985). In the present case, the upper and lower first primary molars on the left side developed periapical abscesses and were extracted. Bouvier et al. (2008) published a case report of long-term rehabilitation in a child with DI. At age 6 years, the patient’s primary second and permanent first molars were protected with stainless-steel crowns to increase the vertical dimension and to protect them from further attrition. All remaining permanent anterior teeth and premolars were crowned immediately after eruption with polycarbonate resin crowns, while the second molars were protected with stainless-steel crowns.
Clinical manifestations and dental management At age 14.5 years, the child began long-term prosthetic rehabilitation once the maxillary growth was determined to be stable. All provisional crowns were removed, and dental preparations were completed for individual low-fusion ceramic–metal crowns. Maxillary molars were fitted with ceramic crowns with metal occlusal surfaces. In conclusion, shields type I DI associated with OI is a hereditary disorder characterized by fragile bones and dentin dysplasia. Patients with this condition should be diagnosed and managed as soon as possible when the primary teeth start to erupt. Comprehensive medical and dental care should be provided, with full coordination among the pediatricians, dentists, and multiple specialties, to prevent dental diseases, maintain esthetics, occlusion, and function, and reduce tooth wear and hypersensitivity from childhood through adulthood. Conflict of interest We wish to confirm that there are no known conflicts of interest associated with this publication and there has been no significant financial support for this work that could have influenced its outcome. References Bischoff, H., Freitag, P., Jundt, G., Steinmann, B., Tyndall, A., Theiler, R., 1999. Type I osteogenesis imperfecta: diagnostic difficulties. Clin. Rheumatol. 18 (1), 48–51. Bouvier, D., Leheis, B., Duprez, J.P., Bittar, E., Coudert, J.L., 2008. Dentinogenesis imperfecta: long-term rehabilitation in a child. J. Dent. Child (Chic). 75 (2), 192–196. Elnagdy, G., ELRefaiey, M., Aglan, M., Ibrahim, R., ELBadry, T., 2012. Oro-dental manifestations in different types of osteogenesis imperfect. Austr. J. Basic Appl. Sci. 6 (12), 464–473. Gahagan, S., Rimsza, M.E., 1991. Child abuse or osteogenesis imperfect: how can we tell? Pediatrics 88 (5), 987–992. Hodge, H., Finn, S., Robinson, B.G., 1940. Hereditary opalescent dentin, III: histological, chemical and physical studies. J. Dent. Res. 19 (6), 521–536. Huber, M.A., 2007. Osteogenesis imperfecta. Oral Surg. Oral Med. Oral Pathol. Oral Radiol. Endod. 103 (3), 314–320. Iwamoto, J., Takeda, T., Sato, Y., 2004. Effect of treatment with alendronate in osteogenesis imperfecta type 1: a case report. Keio J. Med. 53 (4), 251–255. Tim Wright, J., 1992. The diagnosis and treatment of dentinogenesis imperfect and amelogenesis imperfect. Hellenic Dent. J. 2, 17–24. Kim, J.W., Simmer, J.P., 2007. Hereditary dentin defects. J. Dent. Res. 86 (5), 392–399. Kruse, R.W., Harcke, H.T., Minch, C.M., 1997. Osteogenesis imperfecta (OI), may be mistaken for child abuse. Pediatr. Emerg. Care 13 (3), 244–245. Levin, L.S., 1981. The dentition in the osteogenesis imperfecta syndromes. Clin. Orthop. Relat. Res. 159, 64–74. Lindau, B., Dietz, W., Lundgren, T., Storhaug, K., Noren, J.G., 1999. Discrimination of morphological findings in dentine from osteogenesis imperfecta patients using combinations of polarized light
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