References

Devaraju D, Devi B, Vasudevan V, Manjunath V. Dentinogenesis imperfecta type I: a case report with literature review on nomenclature system. J Oral Maxillofac Pathol. 2014; 18:S131-S134
Mars M, Farrant S, Roberts G. Dentinogenesis imperfecta. Report of a 5-generation family. Br Dent J. 1976; 140:206-209
Hodge H, Finn S, Lose G, Gachet F, Bassett S. Hereditary opalescent Dentin II: general and oral clinical studies. J Am Dent Assoc. 1939; 26:1663-1674
Roberts E, Schour I. Hereditary opalescent dentine (dentinogenesis imperfecta). Am J Orthod Oral Surg. 1939; 25:267-276
Shields E, Bixler D, el-Kafrawy A. A proposed classification for heritable human dentine defects with a description of a new entity. Arch Oral Biol. 1973; 18:543-553
de La Dure-Molla M, Philippe Fournier B, Berdal A. Isolated dentinogenesis imperfecta and dentin dysplasia: revision of the classification. Eur J Hum Genet. 2015; 23:445-451
Rajpar M. Mutation of the signal peptide region of the bicistronic gene DSPP affects translocation to the endoplasmic reticulum and results in defective dentine biomineralization. Hum Mol Gen. 2002; 11:2559-2565
Martin E, Shapiro J. Osteogenesis imperfecta: epidemiology and pathophysiology. Curr Osteoporos Rep. 2007; 5:91-97
Barabas GM. The Ehlers–Danlos syndrome. Abnormalities of the enamel, dentine, cementum and the dental pulp: an histological examination of 13 teeth from 6 patients. Br Dent J. 1969; 126:509-515
Bonaventure J, Stanescu R, Stanescu V Type II collagen defect in two sibs with the Goldblatt syndrome, a chondrodysplasia with dentinogenesis imperfecta, and joint laxity. Am J Med Gen. 1992; 44:738-753
Witkop C. Hereditary defects in enamel and dentin. Hum Hered. 1957; 7:236-239
Malmgren B, Lindskog S, Elgadi A, Norgren S. Clinical, histopathologic, and genetic investigation in two large families with dentinogenesis imperfecta type II. Hum Genet. 2004; 114:491-498
Sapir S, Shapira J. Dentinogenesis imperfecta: an early treatment strategy. Paediatr Dent. 2001; 23:232-237
Abukabbos H, Al-Sineedi F. Clinical manifestations and dental management of dentinogenesis imperfecta associated with osteogenesis imperfecta: case report. Saudi Dent J. 2013; 2:159-165
Op Heij DG, Opdebeeck H, van Steenberghe D, Quirynen M. Age as compromising factor for implant insertion. Periodontology 2000. 2003; 33:172-184
Schwarz WD. Prosthetic treatment of patients after bone grafting procedures. Br J Oral Surg. 1982; 20:45-52
Chetty M, Roberts T, Stephen LX, Beighton P. Dental implications of bisphosphonate therapy in osteogenesis imperfecta. S Afr Dent J. 2017; 72:424-428
Knezovic-Zlataric D, Celebic A, Lazic B. Resorptive changes of maxillary and mandibular bone structures in removable denture wearers. Acta Stomat Croat. 2002; 36:261-265
Thomason JM, Kelly SA, Bendkowski A, Ellis JS. Two implant retained overdentures – a review of the literature supporting the McGill and York consensus statements. J Dent. 2012; 40:22-34
Farges JC, Alliot-Licht B, Renard E Dental pulp defence and repair mechanisms in dental caries. Mediators Inflamm. 2015; 2015 https://doi.org/10.1155/2015/230251
Guidelines on dental management of heritable dental developmental anomalies. Pediatr Dent. 2013; 35:E179-184
Ball SP, Cook PJ, Mars M, Buckton KE. Linkage between dentinogenesis imperfecta and Gc. Ann Human Genet. 1982; 46:35-40
Mantzourani M, Sharma D. Dentine sensitivity: past, present and future. J Dent. 2013; 41:S3-17
Swift EJ Literature review bonding systems for restorative materials – a comprehensive review. Pediatr Dent. 1998; 20:80-84

Dentinogenesis imperfecta: Development of treatment strategies over 40 years

From Volume 47, Issue 11, December 2020 | Pages 928-933

Authors

Claire Forbes-Haley

BDS, MJDF RCS, FGDP UK, FDS Res Dent RCS

Consultant in Restorative Dentistry, School of Oral and Dental Sciences, Bristol Dental Hospital, Lower Maudlin Street, Bristol BS1 2LY, UK

Articles by Claire Forbes-Haley

S Nandra

Dental Core Trainee, Restorative and Paediatric Dentistry

Articles by S Nandra

Surina Bhola

BDS(Hons), MFDS RCPSG, PgCert(DentEd)

Dental Core Trainee in Restorative Dentistry, Bristol Dental Hospital, Lower Maudlin Street, Bristol BS1 2LY, UK

Articles by Surina Bhola

A Najran

Dental Core Trainee, Restorative and Paediatric Dentistry, Bristol Dental Hospital, Lower Maudlin Street, BS1 2LY, UK

Articles by A Najran

Abstract

Dentinogenesis Imperfecta (DI) is an inherited autosomal dominant disorder of dentine formation, which affects both primary and permanent dentitions. This paper discusses four cases of DI within one family over three generations and illustrates how increased knowledge of this condition and different severities of the condition are managed differently. This case series represents a family of three generations, the grandmother, her children (son and daughter) and her granddaughter (son's daughter), who all have been affected by DI. This paper summarizes the restorative rehabilitation of each family member, spanning over the last 40 years.

CPD/Clinical Relevance: These generational cases show how dental care has progressed over time, highlighting the need for early identification of DI. Sharing information and strategies on the management of rare dental conditions will improve patient care and outcomes.

Article

Dentinogenesis imperfecta (DI) is an inherited disorder of dentine formation. Together with dentine dysplasia (DD), they encompass a group of autosomal dominant traits, affecting both primary and permanent dentitions. Teeth affected by these conditions have been described as opalescent, exhibiting a distinctive opalescent-grey-brown discoloration. The enamel of affected teeth may be hypoplastic and can crack away from the dentine.1 The exposure of the underlying defective dentine results in excessive tooth surface loss. Studies show that, by the age of 3 years, primary teeth can be worn to gingival level, with first permanent molars worn to this extent by the age of 6.5 years.2 The principal aim of treatment is to prevent caries and loss of tooth structure, and to maintain space, where required, to allow for further management.

Classification

Hereditary opalescent dentine was first used in 1936 to describe defects of dentine that were not associated with systemic disorders.3 The term ‘dentinogenesis imperfecta’ was then coined to describe the dental phenotypes associated with ‘osteogenesis imperfecta’ (OI) in 1939.4 Following these, in 1973, Shields proposed a classification system including three categories of dentinogenesis imperfecta (DI I, II and III) and two of dentine dysplasia (DD I and II); this was the classification used for many years.5 However, many cases reported patients who had clinical signs that spanned multiple types of DD and DI. Therefore, it was decided that clinical signs alone were insufficient to classify DI, and that molecular/genetic analysis was also necessary.

In 2015, de La Dure-Molla et al6 proposed a revised classification that separated syndromic and isolated forms of DI, taking into the account the severity of genetic expression of a gene mutation in the DSPP gene (dentine sialophosphoprotein), located in human chromosome 4q22.1.7 This gene encodes major protein constituents of dentine. The revised classification simplifies DI to mild, moderate and severe. Table 1 outlines the clinical and radiographic signs that may be exhibited in these forms of DI, as proposed by de La Dure-Molla.


Mild (previously Shields II DD) Moderate (previously Shields II DI) Severe (previously Shields III DI)
Crown discoloration Normal/light grey Blue/grey/amber opalescent Brown opalescent
Crown morphology Bulbous (increased constriction at CEJ) and short crown
Attrition Increased severity from enamel chipping to whole crown disappearance
Pulp obliteration Partial obliteration with ‘thistle-shaped’ appearance Narrowed pulp/complete obliteration Enlarged pulp with ‘shell-teeth’ appearance
Thin and short root Increased severity
Periapical pathology Increased severity with number

Aetiology

Some types of DI are linked to systemic conditions such as OI. This disorder is caused by a mis-sense mutation of the two genes that encode for type I collagen (COL1A1 and COL1A2).8 Tissues in which type 1 collagen is the main matrix protein are affected and include bone, sclera and dentine. Clinically, OI is characterized by brittle bones prone to fracture, a short stature and blue sclerae. Other systemic conditions associated with the DI-type phenotype are Ehlers–Danlos9 and Goldblatt syndromes.10

Prevalence

Wiktop reported that DI affects approximately 1 in 6000 to 8000 people.11

Diagnosis

This is based on patient history, clinical examination and radiographic findings. The diagnosis of hereditary DD is based on a family history with a pedigree construction and a comprehensive clinical examination. Molecular diagnosis may be useful because several disease-causing mutations have been identified.

Medical history will reveal whether this has a systemic component. For example, a history of OI would reveal details such as bone fractures with minimal trauma. OI is usually identified in childhood. This part of the medical history and, therefore, is usually identified easily. A family history will identify a pattern of inheritance of OI, DI or DD. A dental history may reveal problems in the primary dentition associated with the condition, such as toothwear, dental abscesses (due to pulpal involvement secondary to extensive attrition) and loss of occlusal face height.

Clinical examination would identify extra-oral features of OI, such as blue/grey sclera, triangular face, spinal curvature, and patients usually have a history of multiple bony fractures. Intra-oral examination will reveal amber-brown to grey-blue opalescent discoloration of the dentition.12 As the enamel in primary teeth is thinner in some types of DI, the discoloured dentine will show through. Tooth enamel may be hypomineralized,13 appear normal, or have sheared off, leaving exposed dentine that is prone to rapid attrition. For this reason, tooth surface loss may be evident.

Radiographic examination reveals teeth with bulbous crowns, marked cervical constriction and short, thin roots. Pulp chambers may appear normal or be completely obliterated (Figure 1). Multiple periapical radiolucencies with no evidence of caries may be present.

Figure 1. Radiographic examination revealing obliterated pulp chambers.

The multidisciplinary team approach

Initial diagnosis of DI is most likely to occur through the general dental practitioner (GDP), after which, multiple teams may be involved in the patient's care. The teams and their role in care are discussed below.

Paediatrics

Once identified, referral to a local paediatric dental unit is advisable. It is important that, as a child, patients with this condition have a positive relationship with dental healthcare professionals. It is ideal to minimize the interventions required through education of the parents on diet, hygiene, fluoride and preventive strategies.14

Care is often shared between GDPs and hospital dentistry for the majority of a patient's lifetime. A transition clinic at the age of 15 years allows planning with the paediatric and restorative dental teams for future care. It helps to prepare children and parents for what further treatment may be required, and ensures there is no disruption to the care pathway when changing departments.

Orthodontics

Consideration of orthodontic input comes at roughly 10–12 years of age, depending on the rate of tooth development. Orthodontic intervention to align teeth can help ease of brushing, placement of restorations, replacement of teeth when required and interocclusal schemes.13

Restorative

Restorative care usually starts between the ages of 16 and 18 years with the aim of maintaining the natural dentition for as long as possible. Long-term planning and possible alternative interventions should be considered to improve the prognosis for the teeth. This is best done with shared care and planning via tertiary care, where dental professionals have experience of DI. If tooth replacement is required, this can be planned before 21 years of age and take place after growth has stopped.15

Maxillofacial/oral surgery

Oral surgery may be required to assist with extractions because the teeth in DI are brittle and can be difficult to remove.13 The teeth are prone to multiple fractures at the root during extraction. It is important to minimize damage to the bone to maintain good bone height and width in case of tooth replacement. If teeth have been absent for many years, and dentures have been worn, the bone volume can be limited.15 Co-ordination with maxillofacial colleagues over bone grafting and sinus lifting may be required to allow tooth replacement with dental implants.13

Medical teams

Although DI is a condition in its own right, 50% of those with OI have DI with varying degrees and severity.16 OI, also known as brittle bone disease, is a connective tissue disorder that primarily affects the growth of the skeleton and results in bones that fracture easily. To reduce the risk of fractures, bisphosphonate drugs can be prescribed.17 These can have a great impact on the dental management of patients owing to the risk for developing medication-related osteonecrosis of the jaw following surgical procedures. Therefore, dental extractions must only be carried out if absolutely necessary, and prevention of dental disease is important. Close links with the patient's medical teams, general medical practice, rheumatology and orthopaedics is required to manage and support a patient's care appropriately.

Case series

This article reports four cases of DI seen within one family over three generations. Broader details of the family's genetics were published in 1976.2,22

Case 1: Grandmother, 72 years old

This patient was diagnosed with DI in the late 1940s. She had lost the majority of her teeth at an early age and had had complete upper and lower dentures since the age of 28. This style of radical treatment by extractions and dentures was more common in the 1960s20 because there were limited treatment options, patients presented late with worn, decoronated teeth, and the costs of ongoing treatment were high.

On presentation to our department at age 68, after 40 years with full dentures, she had issues with retention of the prosthesis because of reduced bone volume.18 Two dental implants with locators were placed in the mandible (Figure 2) to improve retention,19 which allowed better control of the full dentures.19

Figure 2. (a–c) Grandmother: clinical photographs and radiographs showing full dentures (implant-retained lower denture).

Case 2: Daughter, 50 years old

This patient's primary dentition was affected. DI can affect primary dentition to varying degrees, with the teeth exhibiting similar features to the adult dentition.21 This helps with early diagnosis and appropriate paediatric management, such as patient education and preparation for the management of their permanent dentition.

Both the daughter and son received initial treatment at the Royal Dental Hospital in London, and were seen subsequently at Great Ormond Street Hospital for their dental care. After the family moved, their primary treatment was carried out in a dental practice in Bath, before they were referred to Bristol Dental Hospital.

The daughter's intervention required coverage of the teeth to help to reduce the rate of wear on her dentition and to improve the appearance. This started with indirect full coverage restorations. Owing to the bulbous crown shape and large pulp chambers, many of these teeth required root canal treatment (RCT).5 After RCT, little cervical dental tissue remained and multiple teeth fractured at the gum level, which required extraction.

At the time of presentation to the dental hospital, the patient had an upper partial denture, the surrounding teeth were heavily restored and they had a limited long-term prognosis. The lower dentition was heavily restored with indirect restorations. The upper jaw was converted into implant-retained bridgework, split at the midline (Figure 3). After placement of the upper implant bridge, more teeth in the lower jaw failed, possibly due to the relative force on the lower teeth from the now stable and strong upper implants.19 Further implants were placed where spaces were present and where teeth failed in the mandible. This gave improved support to the remaining natural dentition in the lower jaw.

Figure 3. (a–e) Daughter: clinical photographs showing implant-retained fixed prosthesis. OPTs show progression from full mouth crowns to implant-supported bridges.

Case 3: Son, 48 years old

This patient's primary and permanent teeth were affected by DI. This is in part due to the genetic relationship and inheritance of the condition. As a result of learning from the care given to his sister, he has required fewer full coverage restorations. There has also been use of gold onlay work and composite restorations, which has reduced the tooth preparation required (Figure 4). He still has the majority of his own permanent dentition.

Figure 4. (a–i) Son: clinical photographs showing full coverage anterior crowns and posterior bitewings.

Case 4: Granddaughter (son's daughter), 21 years old

The severity of this patient's DI is similar to her father's, appearing less severe than her grandmother's and aunt's conditions. (Her first cousins, children of her aunt described above, show no signs of DI).

Initially, she was managaed conservatively by her GDP who then referred her for paediatric advice, where direct composite resin restorations on the upper anterior teeth, and metal non-preparation onlays onto the first molars were placed. This started her care on the multidisciplinary team pathway. She required no orthodontics and at age 16 years, she was transferred to the restorative department.

Prevention played a large part in allowing her to maintain her dentition into adult life with little intervention, and involved early diet and brushing advice with regular GDP support. Once in restorative care, the direct composite restorations were removed and at-home whitening treatment was performed over a long period to avoid sensitivity. The whitening treatment improved the tooth colour, but further camouflage, using minimal labial composite veneers improved the appearance further, to the patient's satisfaction (Figure 5). The use of direct composite resin restorations avoided destructive tooth preparations and has allowed refreshment and maintenance of the current restorations.

Figure 5. Granddaughter: clinical photographs of (a) before and (b) after (home bleaching and direct composite resin veneers). (c) OPT taken age 10 years showing bulbous crown form and obliterated canals.

Discussion

Restorative challenges

As each patient's DI exhibits a different severity,11 a standard prescription for treatment is unlikely to be appropriate.

Common issues for patients with DI/DD

Generalized sensitivity

This is due to thin or lost enamel leaving the more temperature-sensitive dentine exposed.23 This can cause problems with eating, but more commonly, brushing. Brushing with direct pressure onto the dentine can be very uncomfortable. Standard methods of sensitivity control can be tried, such as topical applications, toothpastes and overnight treatments in guards. For many, minimally invasive treatments may not be enough, and direct restorations in glass ionomer cement may be needed to allow more comfortable brushing.

High caries rate

With the lack of surface enamel, consequent dentine sensitivity and difficulties with brushing, there is a high risk of dental caries. Caries destroys dentine at a faster rate than enamel,20 and without the hard protective enamel shell, large amounts of dentine can be damaged quickly. Patients with DI/DD are at high caries risk and the use of high fluoride toothpaste is recommended.21 These patients also require regular review every 6 months at least, to check hygiene and for possible carious lesions.

Difficult root canal treatments

Due to the potential for rapid caries progression, apical pathology can develop quickly, and on multiple teeth.21 The pulp chamber can be difficult to find, and can be obliterated and/or have calcifications.21 The canals themselves can be narrow and difficult to locate. Root canal treatment is more challenging, often with a poor prognosis; these patients appear to lose teeth more quickly as a result of RCT.

Challenging restorative care

The lack of enamel and large pulp chambers make simple restorations risky – the chance of pulp damage is high. Once a tooth with bulbous crowns has had RCT, very little tooth tissue remains at the cementoenamel junction5 leaving it prone to facture at the gingival level. Using additive restorations, such as composite resin, onlay/overlay restorations and avoiding unnecessary interventions can help to maintain the teeth for longer.21 Using the surrounding teeth for bridgework is usually not possible because of the likely heavy restoration and the possibility of crown fracture.

Poor appearance

The general colour of the teeth can be grey to red/brown. This can look like staining or caries, and can be misinterpreted as dental neglect. Patients with DI/DD often wish to mask this discoloration. To maintain as much natural tooth as possible, conservative means are necessary. Planning and treatment should be considered under the guidance of a dentist with experience in such cases, to ensure the best long-term outcomes. Placement of crowns and veneers can be more damaging than on the average dentition, owing to the thin enamel and large pulp chambers. These interventions increase the chance of devitalization of the pulp. Additive restorations, onlays, composite resin, bonded restorations and ‘no preparation’ veneers require less enamel removal or damage.

Changing times

Late identification of the condition in the grandmother, the first generation affected by DI, resulted in multiple decoronations and high caries. In her youth, the lack of fluoride availability exacerbated the condition. The first fluoride toothpaste in the UK was marketed in 1958 and regular application of fluoride varnishes was implemented in the 1980s. Early replacement of teeth by dentures was seen as acceptable care. Expectations are now different and, as a result, earlier and better intervention is essential.

Rapid changes in care were seen for the second generation affected by DI. Earlier identification for both the daughter and the son ensured retention of more of their natural dentition into adulthood. Progression of care into indirect restorations was done in the tertiary care setting, and problems that arose during the daughter's care were repeated in the son's care plan. Success of this is clearly evident in the retention of the son's permanent teeth.

DI in the third generation, the granddaughter, was identified early and treated using a mutidisciplinary team approach. This allowed ultra-conservative management of her adult dentition, and, as a child, high levels of prevention and appropriately used fluoride protected the developing dentition.21 The development of composite resin and bonding24 meant that these materials and techniques were used to their full potential.

Conclusion

These generational cases show how care has changed over time and highlight the need for early identification of DI. They also show the importance of reflective practice in how rare dental conditions are managed. It is essential to share information and strategies on management of rare dental conditions to improve patient care and outcomes.