Dental rehabilitation after surgically acquired bone deficiency related to tumour treatment remains a challenge. The insertion of patient-specific implants geared to the contour of the remaining bone is a feasible method of supporting fixed or removable dentures. As oral health-related quality of life (OHRQoL) is of great interest in these cases, 12 individuals treated with patient-specific implants for severe bone deficiency were surveyed and their Oral Health Impact Profile (OHIP) scores after dental rehabilitation were evaluated. The OHIP-G53 questionnaire was used to measure overall treatment outcomes. The distribution of OHIP sum-scores for participants treated with patient-specific implants was almost homogeneous when compared to those cited in the literature for patients treated with conventional dental implants. OHIP items related to functional impairment and physical pain showed the highest scores (occurring occasionally), and financial loss related to treatment was frequently stated. Moreover, higher scores were detected in almost all OHIP dimensions for participants with patient-specific implant-supported removable dentures. Conversely, those treated with patient-specific dental implants and fixed dentures showed lower psychosocial impact scores and equal or superior OHRQoL. Hence, patient-specific dental implants, especially combined with fixed dentures, can lead to a positive OHRQoL in patients with severe bone deficiencies related to tumour therapy.
Dental rehabilitation after surgical tumour treatment is a key factor related to oral health-related quality of life (OHRQoL) . Acquired bone deficiencies can lead to anatomical situations preventing dental implant insertion and even prosthetic use, especially in cases where bone augmentation is not possible or desired, or where bone deficiency occurs secondarily due to failed bone augmentation procedures . Advances in digital planning procedures, computer-aided design, and selective laser-melting (SLM) techniques have led to the fabrication of patient-specific implants, allowing for individual patient solutions (IPS) in the field of head and neck surgery . New concepts of implant-borne dental rehabilitation have been promoted in cases of severe bone deficiency to overcome the shortcomings of conventional dental implants, and innovative line extensions in implant dentistry have recently been described . However, although the successful clinical use of these new possibilities has been reported, data on the post-treatment OHRQoL of these patients are lacking.
Several studies have focused on the factors influencing patient OHRQoL, especially those related to conventional fixed or removable dentures . However, no one single factor has been found to be crucial for an acceptable post-treatment quality of life; rather, several physical, psychological, and social parameters influence a patient’s subjective well-being after therapy . Different instruments have been used to measure OHRQoL, and standardized protocols have been established in clinical trials . In the present study, the Oral Health Impact Profile (OHIP) questionnaire developed by Slade and Spencer was used to evaluate individual impairments after denture treatment and gain evidence of patient OHRQoL . The OHIP has been found to be reliable and valid for detailed measurement of the levels of dysfunction, discomfort, and disability associated with oral disorders, as well the social impact associated with oral health.
In its original English version (OHIP-E49), the OHIP questionnaire consists of 49 items divided into seven dimensions concerning functional limitations, physical pain, psychological discomfort, physical disability, psychological disability, social disability, and personal handicaps. The OHIP is based on Locker’s conceptual model of oral health, which has been pivotal in the development of oral health-related research . Since the OHIP concept was implemented, the questionnaire has been translated into many languages and validated for different populations . Additionally, despite the potential loss of information, several valid short versions have been developed to simplify its application in daily practice . The OHIP aids clinical decision-making as well as research.
For the German population, the OHIP-G49 and OHIP-G53 (two long versions), as well as several short versions, have been validated with regard to applicability, consistency, and reliability for the assessment of OHRQoL . German demographic factors and the questionnaire’s dimensional structure have also been explored, and German population-based reference values, as well as a specific German classification related to dimension subgroups (psychosocial impact, orofacial pain, oral functions, and appearance), have been generated and validated for scientific analyses .
Although previous oral health investigations have used these instruments, the assessment of OHRQoL has been limited mostly to dentate patients, patients with conventional fixed or removable dentures, and edentulous patients with complete dentures; studies on the OHRQoL of patients treated with dental implants and implant-supported dentures are rare . Data concerning patient-specific dental implants applied in cases of severe bone deficiency and their impact on OHRQoL are lacking. Therefore, the aim of the present study was to investigate the OHIP and OHRQoL of individuals treated with patient-specific implants for dental rehabilitation due to acquired bone deficiency after tumour treatment.
Materials and methods
Twelve patients with an acquired severe bone deficiency of either the upper or lower jaw due to surgical tumour treatment were included in this observational study. All participants received a patient-specific implant (IPS Implants Preprosthetic; KLS Martin Group, Tuttlingen, Germany) for dental rehabilitation ( Fig. 1 ).
Patients who had suffered from a benign or malignant tumour lesion, independent of the tumour entity, and in whom primary or secondary bone augmentation of the defect site could not be performed for the insertion of conventional dental implants were included. After a tumour-free recall interval of at least 6 months, patient-specific dental implants and prosthetic implant-retained dentures were inserted for dental rehabilitation. The patients then had to pass clinical follow-up, this is referring to follow-up in which there were no changes to the pre-planned treatment. The oral health assessment was performed at a minimum of 2 months after insertion of the patient-specific implant/prosthetic denture. Six patients were supplied with patient-specific dental implant-supported fixed dentures and six were supplied with removable dentures.
Patients for whom dental treatment with a patient-specific dental implant and prosthetic implant-retained denture was not fulfilled as primarily pre-planned were excluded. These patients (two of the 14 patients initially identified) had to undergo revision due to the need for secondary surgical and prosthetic adjustment of certain implant parts during therapy (i.e., removal of an implant post or a part of the anchoring scaffold structure) as a consequence of postoperative infection or poor wound healing with the subsequent need for additional circumscribed soft tissue coverage in the course of treatment. Patients with severe bone deficiencies not related to tumour therapy were also excluded.
Relevant characteristics of all patients included are listed in Table 1 .
|Patient number||Sex||Age (years)||Diagnosis||Treated jaw||Implant-supported denture||Patient-specific sum-score|
Oral Health Impact Profile and the OHIP-G53 questionnaire
The German OHIP-G53 version questionnaire was administered to all patients during a personal interview. The questionnaire included 49 questions plus four additional questions specific to the German population concerning different levels of dysfunction, discomfort, and disability associated with the three main functional status dimensions of oral health: social, psychological, and physical. The questionnaire was grouped into the seven original main dimensions (using the English classification, including 49 items): functional limitation (9 items), physical pain (9 items), psychological discomfort (5 items), physical disability (9 items), psychological disability (6 items), social disability (5 items), and handicap (6 items). Furthermore, a German-specific classification of dimensions referring to a reduced number of items (21 of 53 items) grouped according to psychosocial impact (9 items), orofacial pain (6 items), oral functions (3 items), and appearance (3 items) was included in the OHIP assessment. Scores were recorded for each question using a five-point Likert-like scale ranging from 0 to 4 (0 = never or not applicable, 1 = hardly ever, 2 = occasionally, 3 = fairly often, 4 = very often) to calculate patient-specific, single-item, and dimension sum-scores. Questions were asked with reference to oral health in the month prior to the interview.
Analysis of the questionnaire results and OHRQoL assessment
Analysis of the OHIP-G53 questionnaire results was performed using basic descriptive statistics. The patient-specific, single-item, and dimension sum-scores of all participants with patient-specific dental implants and the kind of implant-supported dentures (fixed or removable) used were examined. For patient-specific sum-scores (range 0–212; scale 0–4 × 53 items), the single-item scores in each patient case were added together and the mean value and range were calculated. Single-item sum-scores (range 0–4; scale 0–4 × 1 item) were calculated by adding all scores related to the item; mean values were also generated. Additionally, ranges were assessed within the minimum and maximum score of each single-item sum-score. A mean single-item sum-score value ≥1.5 was defined as an adverse impairment (Likert-type scale 2–4; occasionally to very often) and a value of 0.0 indicated no impairment (0, never or not applicable). Item-related dimension sum-scores were calculated using mean values for the English and German dimension classifications (ranges 0–20, 0–24, and 0–36, and 0–12, 0–24, and 0–36, respectively; scale 0–4 × number of items related to relative dimension). Patient OHRQoL was subsequently assessed with respect to patient-specific, single-item, and dimension sum-scores; higher scores represented poorer OHRQoL. Results were compared descriptively to those reported previously in the literature from OHIP assessments of patients treated with conventional dental implants.
OHIP patient-specific sum-scores
The sum-scores ranged from 4 to 88 in patients treated with patient-specific dental implants; values ranged from 4 to 40 in patients supplied with implant-supported fixed dentures and from 19 to 88 in patients supplied with implant-supported removable dentures. Although the fixed denture group had the lowest score and the removable denture group had the highest score, no significant difference in distribution of scores was detected regarding the type of denture used ( Table 1 ). When the minimum and maximum values referring to the kind of implant-retained denture were excluded from the analysis, the range differed (15–40). The overall mean patient-specific sum-score value was 31.0. A lower mean value was found in those patients with implant-supported fixed dentures when compared to those with removable dentures ( Supplementary Material Table S1).
OHIP single-item sum-scores
The single-item sum-scores were evaluated for all 53 items of the OHIP questionnaire in all cases. None of the cases had missing data. Remarkable overall values for patient-specific dental implants and dentures were detected for questions on having trouble pronouncing words, problems with food catching during meals, impairments involving a sore jaw and sore spots, and non-specific financial loss (values 1.5 to 1.8). Concerning differences between implant-supported fixed and removable dentures, values ≥1.5 were found only in the group with fixed dentures for difficulty chewing, trouble pronouncing words, painful aching and painful gums, and unclear speech (values 1.5 to 1.8). For the group with removable dentures, food catching was the major adverse impairment; this was reported by all patients in this group (value 2.3, range 2–3). This was followed by feeling uncomfortable when eating (value 1.7). Except for impairments concerning food catching during meals in patients with implant-retained removable dentures (value 2.3) and feeling uncomfortable when eating in patients with implant-retained fixed dentures (value 0.5), all mean single-item sum-scores concerning the aforementioned denture-related impairments were between 1.0 and 2.0 (1 = hardly ever, 2 = occasionally).
Among all patients with patient-specific dental implants, no impairments (value 0.0) were reported for worsened digestion or toothache. Patients with implant-supported fixed dentures reported no impairments related to stale breath, feeling miserable, remarkably less flavour in food, eating avoidance, unsatisfactory diet, necessity to interrupt meals, difficulties relaxing, feeling depressed, or being embarrassed due to dentures. Additionally, no impairments were noted among patients with fixed dentures for any of the items regarding social disability, being able to enjoy people’s company, or functioning in daily life and work. With reference to the additional German items, patients with implant-retained fixed dentures further reported no avoidance of eating with others or noticeable temporomandibular joint noise. In contrast, patients with removable dentures reported considerably more impairments. In this group, only impairments due to noticing that a tooth did not look right, sensitive teeth, and reduced self-consciousness were lacking ( Supplementary Material Table S1).
OHIP dimension sum-scores and OHRQoL
Regarding the English classification of dimension sum-scores, physical pain was found to have the highest impact on OHRQoL, whereas the mean values of dimension sum-scores were almost equally distributed between patients with implant-supported fixed and removable dentures compared to the mean value of all patients. Besides physical pain, for which the overall scores for those with patient-specific dental implants were almost equal to those concerning fixed and removable dentures, the use of removable implant-retained dentures led to remarkably higher scores in all other dimensions compared to implant-retained fixed dentures. In particular, no impairments in social disability (value 0.0) were detected in patients with fixed dentures. Conversely, those with patient-specific implant-supported fixed dentures reported higher OHRQoL.
Regarding the German classification of dimension sum-scores, orofacial pain had the highest mean values. Patients with implant-supported fixed dentures had a slightly higher mean value than those with removable dentures, which is concordant with the English classification results. In contrast, the psychosocial impact was markedly higher in patients with implant-supported removable dentures than in patients with fixed dentures (value 4.7 vs. 0.2, respectively). For those with implant-supported fixed dentures, this discrepancy underlined a higher OHRQoL, especially in terms of social and psychological impairments. Regarding oral function and appearance, almost no differences in dimension sum-scores related to the type of denture were detected ( Table 2 ).